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Tire/ Wheel selection

Printed From: Official Baja SAE Forums
Category: General
Forum Name: Design Discussion
Forum Description: Discuss Design, Tech, Cost, and related issues
URL: http://forums.bajasae.net/forum/forum_posts.asp?TID=585
Printed Date: Apr/22/2019 at 4:46pm


Topic: Tire/ Wheel selection
Posted By: rafter40
Subject: Tire/ Wheel selection
Date Posted: Dec/07/2010 at 3:09pm
Hi currently i am looking for a good set of wheels for our car.  We are thinking of going with aluminum rims for weight reasons and using thin width tires in both the front and rear of the car.

I would like some suggestions of specific aluminum wheels to buy/

Also, any draw backs to using aluminum or thin width wheels in the back?

In addition we plan on welding additional protective plates to the rims to prevent the from damage.
We will be using a solid axel with a swing arm if this makes a difference.




Replies:
Posted By: collinskl1
Date Posted: Dec/07/2010 at 3:28pm
There is some discussion about wheels in another thread, you'll find it to be a good read.
 
By "thin" do you mean narrow?  If so, there is definitely a point where narrow is too narrow.  The team that runs dirtbike tires all around comes to mind...  Many teams run narrower front tires than rear, but there are almost as many that run the same thing on all 4 corners.  If you're planning on going to the water race, you might want wider tires in the back.  Once again, there are plenty teams that would say otherwise. 
 
Whatever you do, just pick a combination that will be robust enough to last AT LEAST one race... I'm sure it would suck to not be able to finish or to be severely held up because of a flat. 


-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: ErikHardy
Date Posted: Dec/07/2010 at 3:34pm
OMF has 10x5 aluminum wheels with the protective rings your talking about already welded in. There are heavy but plenty strong


Posted By: LukeS
Date Posted: Dec/07/2010 at 4:39pm
In the past our school has bent a lot of aluminum rims.  No ones still around from when they did this so we dont know how they did it.  Whether it was nose diving, rolling the car, etc is all a guess.

We plan on running aluminum rims off of a Polaris Outlaw.  Same width front and rear.  We'll be bringing extras just incase we blow out a tire or tweak a rim.  The nice thing about running identical wheels is we wont have to buy as many spares.


-------------
University of Regina
http://www.cougar-racing.com


Posted By: CLReedy21
Date Posted: Dec/07/2010 at 5:44pm
Originally posted by ErikHardy ErikHardy wrote:

OMF has 10x5 aluminum wheels with the protective rings your talking about already welded in. There are heavy but plenty strong


We use these ^.

As far as tires go we typically run a 21-22" tall GNCC type front tire for a sport ATV and a 22-24" tall mud tire from a utility quad in the rear.  There are myriad options available for tires, but keeping the weight to a minimum is a common theme among baja teams.  Most tire manufacturers will post weights on their websites, I'd start there.


-------------
-Chris Reedy
TTU Alumni
Fourwheeler Drawer



"Quick with the hammer, slow with the brain."


Posted By: Special Forces
Date Posted: Dec/08/2010 at 2:58am
Originally posted by LukeS LukeS wrote:

In the past our school has bent a lot of aluminum rims.  No ones still around from when they did this so we dont know how they did it.  Whether it was nose diving, rolling the car, etc is all a guess.

We plan on running aluminum rims off of a Polaris Outlaw.  Same width front and rear.  We'll be bringing extras just incase we blow out a tire or tweak a rim.  The nice thing about running identical wheels is we wont have to buy as many spares.


Very possible another team ran into your past team's rims and bent them. Ask me how I might know that. It's amazing what can happen during a race.


-------------
Joe
SUNYIT Baja SAE President
sunyitbaja.com


Posted By: Red_Beard
Date Posted: Dec/08/2010 at 10:09am
Originally posted by Special Forces Special Forces wrote:

Originally posted by LukeS LukeS wrote:

In the past our school has bent a lot of aluminum rims.  No ones still around from when they did this so we dont know how they did it.  Whether it was nose diving, rolling the car, etc is all a guess.

We plan on running aluminum rims off of a Polaris Outlaw.  Same width front and rear.  We'll be bringing extras just incase we blow out a tire or tweak a rim.  The nice thing about running identical wheels is we wont have to buy as many spares.


Very possible another team ran into your past team's rims and bent them. Ask me how I might know that. It's amazing what can happen during a race.


I'm pretty sure we blew two rear tires on teams car doing this last year.


-------------
SDSM&T 09-10 Team Lead
2nd & 9th Baja West

Project Engineer
Matrix Service - Bellingham, WA


Posted By: collinskl1
Date Posted: Dec/08/2010 at 12:08pm
As dumb as they look, I suggested this year's team to add bumpers to the car... We went from 2nd place in the water to about midpack after someone rammed our fender and rear floatation at RIT.

-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: rafter40
Date Posted: Dec/08/2010 at 6:40pm
Thanks for your help.
and collin by thin i do mean narrow.
 
im looking at AMS 10" x 5"  or 10" x 8" Cast aluminum wheels
im leaning toward the 10' x 5" for all four wheels
these are available with bolt patterns of 4/144 and 4/156 
 
im now in search of
1) hubs for the front wheels that would match either bolt pattern
2) tires around 22" to 24" tall
       Im aware of some negatives to even taller say 26" tires such as weight and overall change in gear ratios. but are there any other negatives? Or has any one had bad experience with them?
We are designing our car so we can  change gear ratios quite easily.
 
suggestions/ places to look/ experiences would be greatly appreciated
 


Posted By: ErikHardy
Date Posted: Dec/08/2010 at 7:17pm
Both patterns are fairly common. Off the top of my head the honda trx race quads use 4/144 and I've got raptor hubs laying around that are 4/156.

Tires - rocky mountain catalog is one of millions

26 in wheels are bigger than most. They come in handy in the rough terrain but other than that they are just anchors. I would say the tire choice is highly dependent on the track. The rougher, the bigger.


Posted By: jeiB
Date Posted: Dec/08/2010 at 7:59pm
polaris uses 4/156 as well, vert cheap as well. You will get much lighter rims if you get the rolled aluminium ones from douglas compared to the cast wheels. They arent very durable though, 2 races at most. Last year we used 25" tires. I did quite a bit of research and I think i found the lightest one possible. Just the tires were +2/3 lbs each but frankly it gave a great look and handled really well. One good thing about tall tires if you dont need as much travel. Btw polaris sponsorship does have the carlisle 489 in 25in. Probably the lightest 25in tires out there...

-------------
Jeremie B.
McGill Baja Racing
2009-2011 Captain
minibaja.mcgill.ca


Posted By: rafter40
Date Posted: Dec/08/2010 at 8:25pm

Great help. I have searched to find the polaris sponsorship link or a way to apply but i have found neither.  Could you guide me in the right direction or possibly post a link?  I had wanted to get brakes from polaris through the sponsorship before if my memory is correct. I couldnt figure it out then either

edit: is this correct http://www.polarissuppliers.com/sae_team/Polaris_SAE_Sponsorship.htm - http://www.polarissuppliers.com/sae_team/Polaris_SAE_Sponsorship.htm


Posted By: jeiB
Date Posted: Dec/08/2010 at 8:27pm
you  are right, it isnt easy to find, type polaris sponsorship and you will find it in the first hit but here you go

http://www.polarissuppliers.com/sae_team/Polaris_SAE_Sponsorship.htm


-------------
Jeremie B.
McGill Baja Racing
2009-2011 Captain
minibaja.mcgill.ca


Posted By: rafter40
Date Posted: Dec/08/2010 at 8:28pm

beat me to it thank you

Jeib when your team used 25" tires did you test against them using a smaller size tire?


Posted By: AndyRIT
Date Posted: Dec/08/2010 at 9:49pm
You really should get a wide range of tires and test them, You will have a better outcome then picking something that you think will work.  I spent many hours in the RIT cars when we were selecting tires, do your best to mimic the conditions you will run into.

-------------
RIT Baja SAE Alumni 04'-09'
RIT Baja Team Manager 06'-08'
2010 RIT Track builder
2011 CAT/IL Comp Team Leader
2012 Wis vol
2013 RIT Track Builder
Diesel Calibration Engineer-Kohler Engines


Posted By: collinskl1
Date Posted: Dec/09/2010 at 2:45pm
Originally posted by jeiB jeiB wrote:

One good thing about tall tires if you dont need as much travel.
 
I'm not sure I agree with this.  Tire height has nothing to do with suspension travel.


-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: jeiB
Date Posted: Dec/09/2010 at 3:09pm
well, i was referring to the ball joint angle. Taller tires allow for less misalignment of the ball joint for the same ground clearance of smaller tires.


-------------
Jeremie B.
McGill Baja Racing
2009-2011 Captain
minibaja.mcgill.ca


Posted By: ErikHardy
Date Posted: Dec/09/2010 at 3:25pm
Kyle,
With the same rim diameter, larger diameter tires have an increased sidewall distance, the sidewall of the tire acts as an undamped spring, affecting the overall wheelrate (shocks & springs). Apart from what jeib mentioned about ground clearance.


Posted By: collinskl1
Date Posted: Dec/09/2010 at 3:37pm
I understand what both of you are saying, but none of those things are a function of tire HEIGHT other than ground clearance, when everything else is the same. 
 
JeiB, you can design control arms that place the ball joints properly such that misalignment is less of an issue.  I'm just being overly picky and argumenative Geek
 
One thing I always liked about larger tires was that they roll over obstacles easier.  It's the same thing in practice as the 29" mountain bike trend that's caught on in the last few years.  As mentioned before, more rubber means more weight and rotating mass.  Lipscomb used to run 26x9R11 in the back and 24x8R11 up front... those cars were monster trucks that would practically roll over the logs course designers layed out.  In the quest for lightness we have moved those front tires to the back and now run a 21 skinny up front.


-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: Red_Beard
Date Posted: Dec/09/2010 at 7:38pm
Originally posted by jeiB jeiB wrote:

One good thing about tall tires if you dont need as much travel. Btw polaris sponsorship does have the carlisle 489 in 25in. Probably the lightest 25in tires out there...


Don't agree with either one of these.  I designed in and used as much travel as I could; if your tires aren't on the ground they aren't pushing you forward.  I can guarantee the 489 isn't the lightest tire in the 25" flavor, especially in actual weights.


-------------
SDSM&T 09-10 Team Lead
2nd & 9th Baja West

Project Engineer
Matrix Service - Bellingham, WA


Posted By: collinskl1
Date Posted: Dec/10/2010 at 10:04am
Originally posted by Red_Beard Red_Beard wrote:

Originally posted by jeiB jeiB wrote:

One good thing about tall tires if you dont need as much travel. Btw polaris sponsorship does have the carlisle 489 in 25in. Probably the lightest 25in tires out there...


Don't agree with either one of these.  I designed in and used as much travel as I could; if your tires aren't on the ground they aren't pushing you forward.  I can guarantee the 489 isn't the lightest tire in the 25" flavor, especially in actual weights.
 
I knew I wasn't going crazy!  It's very important to consider the fine line between light weight and robustness... as with everything else in baja.  Don't pick a feather light tire on a heavy car or you'll be sorry.


-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: Red_Beard
Date Posted: Dec/10/2010 at 10:07am
Originally posted by collinskl1 collinskl1 wrote:

Originally posted by Red_Beard Red_Beard wrote:

Originally posted by jeiB jeiB wrote:

One good thing about tall tires if you dont need as much travel. Btw polaris sponsorship does have the carlisle 489 in 25in. Probably the lightest 25in tires out there...


Don't agree with either one of these.  I designed in and used as much travel as I could; if your tires aren't on the ground they aren't pushing you forward.  I can guarantee the 489 isn't the lightest tire in the 25" flavor, especially in actual weights.
 
Don't pick a feather light tire on a heavy car or you'll be sorry.


I'll disagree with you here, I would pick the feather light.


-------------
SDSM&T 09-10 Team Lead
2nd & 9th Baja West

Project Engineer
Matrix Service - Bellingham, WA


Posted By: collinskl1
Date Posted: Dec/10/2010 at 10:16am
I simply mean that light 2 ply tires on the thinnest wall douglas rims supporting a 500 pound car might not be the best idea.  They would be punished over every rock, log, stump, THORN, etc. and you'd be begging for a puncture or bent wheel.  Once again, this is an area that many teams probably don't commit due dilligence.  That said, it would be fairly easy to scrape by with a non ideal combination, too.

-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: dillon_b12
Date Posted: Dec/10/2010 at 11:46am
Originally posted by jeiB jeiB wrote:

You will get much lighter rims if you get the rolled aluminium ones from douglas compared to the cast wheels. They arent very durable though, 2 races at most.


Way too many factors involved to say they'll be toast after two races.  

Here's my opinion on wheel and tire selection based on our cars.  For some background, our cars are typically light (<400lbs.), and do well in most events involve handling/speed.  They are lowish and wide.  If you plan on building a heavier crawler type car that will excel in rougher S&Ts and rock crawl, it's possible that very little of this will apply to you.

Wheels:  Rolled aluminum or HiPers are the way to go.  Steel and cast aluminum are too heavy. Douglas offers a variety of flavors that let you choose how much weight you can live with.  HiPers seem to be pretty tough, although they aren't as light as some of the aluminum options and are considerably more expensive.  Douglas Blue Labels (.125") are about as light as you can get, but they are barely strong enough to make it through more than a race or two.  Keep a dead-blow handy.  Douglas Black Labels(.160") are a good compromise between weight and strength and what I would recommend to most teams running cars similar in philosophy to ours.  Douglas Red Labels(.190") are plenty strong for just about anything they'll see on a Baja course.  10" wheels are nice since that's typically a sport size which means there are a ton of sport(read:light) tire options out there.

Tires: I like something in the 21"-23" range.  I like 23" since the extra size helps you roll over obstacles, and you get a little extra wheel protection.  For fronts, I like a tall center lug section(Maxxis Razr, Razr2, BallanceRazr, ITP Holeshot GNCC...) to dig deep when throwing it hard into corners.  For rears, I want a ton of forward bite and not too much side bite.  The idea being that the lack of much side bite will allow the car to slide more readily while still having a ton of grip for everything else.  ITP Mudlite ATs, Carlisle 489s, and Kenda Bearclaw EXs are good examples of what I mean. Despite the extra weight, I'll take a 4-ply or 6-ply tire over a 2-ply any day.  The 2-ply OEM tires and Carlisle 489s that we have played with are just too soft.  I'm not sure if I'd feel comfortable running Douglas Black Labels with them.


Posted By: dillon_b12
Date Posted: Dec/10/2010 at 11:58am
Originally posted by rafter40 rafter40 wrote:

these are available with bolt patterns of 4/144 and 4/156 
 
im now in search of
1) hubs for the front wheels that would match either bolt pattern

4/144 is Honda's common front sport pattern.  Same for 4/156 except it's Yamaha.

There are a ton of ATVs with those bolt patterns.

Here's a couple for starters:
Honda 450R
Yamaha Raptor

New hubs are spendy, eBay is your friend.


Posted By: tp
Date Posted: Dec/11/2010 at 3:46am
After a number of years of going through wheels and tires on our Baja cars, ATVs, bikes, ect. here are a couple of things that I have come up with.

Wheels: Expensive is not always best. Nor do you always need beadlocks. Hell I run 4 PSI in my sand tires and have yet to unset a bead. A lot of the time you can get past having a bead lock by having a good internal bead. When I look at wheels I look at weight and potential stress risers. Look at a Douglas .190 and an ITP T9. I have cracked the ITPs but I've taken the Douglas wheels to hell and back and they're still fine. All because of the thin sections on the ITPs. Make sure you know what alloy aluminum the wheels is too. Some of the manufactures like to cut costs by using some unknown grade Chinese poop aluminum. I like to see a decent lip on a wheel. Rock rings aren't necessary, but I've bent my fair share of lips. Finally, be sure you pick the right size. My personal preference is to get the wheel as small as possible just so I can have more tire side wall (more buffer). Also it's less area for mud to pack in. Most wheels out there are 8, 10 or 12".

Tires: Tires are even more of a crap shoot. There are so many choices for tread, ply, weight, size, ect.

Size: It's all about what you want to do. The first thing is to make sure your tire is tall enough that when your suspension bottoms your chassis won't hit the ground. Having to tall of a tire will obviously increase your CG but it'll also increase your clearance. So it's up to you. The biggest thing with tire size is gearing. Taller tire means taller top speed but the Briggs can't always pull that. Splitting tire sizes between the front and rear is perfectly fine and actually can let you optimize your tire size to what you have for suspension.

Tread: Again this is about what you want. An aggressive tread will give you more traction but will increase rolling resistance. If the course is muddy these tires can be good, but if its dry these are unnecessary. Obviously a less aggressive tread will do just the opposite. I like finding somewhere in between because too aggressive of tread will make it hard to slide the car. Since most ATV tires are rounded, many tires will have a mild center strip with some aggressive biters on the outer edge of the tire. I really like these for fronts. And no Baja car has enough power to turn sand paddles. I promise.

Ply: This pretty much determines how stiff a tire is going to be. On the front of our car we went from a 2-ply to a 6-ply and I have yet to dent a rim with the new tires. Usually though more ply means more weight. Not always though.... Wink

Weight: Kind of the same thing I was saying with wheels. Less weight out here means less unsprung weight which is always a good thing.


Looking at a manufactures website, ordering tires and just sticking with them will never work. Each year I am ordering new tires to try out to see if there is a combination that I will like more (for both our car and my toys at home). I can talk tires a while and there is a lot I am leaving out. Remember if you find something that you do like always order spares. 

P.S. I've got a nice stack of Carlisle 489s if anyone is interested


-------------
-Tom

Oregon State BajaSAE Team Captain


Posted By: RonGeorge
Date Posted: Dec/12/2010 at 1:33pm

Thanks guys.

@dillion and @tp,

C 489's are 2 ply 23-7-10, correct? I was certainly interested in getting a clarification on dillionb12's statement on 10-Dec-2010 at 10:46am that these tires have a softer "side bite" than forward bite. Do you think all that lateral stiffness with higher 4 and 6 ply tires is really necessary and does it warrant the weight increase you get in the tire? Also, will increasing the psi's in your tire reduce side bite in any way to get the same effect as reducing ply's (just asking)? And finally, how much of a weight difference is there between a 2 and a 4 or 6-ply tire? 



-------------
-Ron George
Systems Engineer (Cummins Turbo)


Posted By: jeiB
Date Posted: Dec/12/2010 at 2:04pm
carlisle 489 , 2ply 13.8lbs
mudlite at 23x8-10, 6 ply, 13.7lbs. We used those two years ago and they are really durable.



-------------
Jeremie B.
McGill Baja Racing
2009-2011 Captain
minibaja.mcgill.ca


Posted By: RonGeorge
Date Posted: Dec/12/2010 at 2:06pm
Weight difference is negligible then. So that's not a concern any more. Thanks.

-------------
-Ron George
Systems Engineer (Cummins Turbo)


Posted By: dillon_b12
Date Posted: Dec/12/2010 at 2:23pm
Originally posted by jeiB jeiB wrote:

carlisle 489 , 2ply 13.8lbs
mudlite at 23x8-10, 6 ply, 13.7lbs. We used those two years ago and they are really durable.


What size 489 is that weight for?


Posted By: jeiB
Date Posted: Dec/12/2010 at 2:26pm
23x7-10, what ron asked for.

http://www.carlisletire.com/products/atv/at489/index.html

EDIT: oups...its 12.4lbs, read the wrong line

-------------
Jeremie B.
McGill Baja Racing
2009-2011 Captain
minibaja.mcgill.ca


Posted By: dillon_b12
Date Posted: Dec/12/2010 at 2:28pm
Ron,

Like any other tire, Carlisle 489s are available in a variety of sizes.  23x7-10 is a 2 ply and weighs 12.4lbs according to data online.  

Maxxis Razr2s(one of my favorites) in a 23x7-10 6 ply come in at 13.7lbs.  Not a huge weight difference anyway and one that I think is offset, to some degree, by the option of running a lighter wheel than you could comfortably do with the 489s.

For me, yes I think the added weight is worth it.  I've seen entirely too many tires ripped off wheels, punctured, or cut.  Peace of mind is a big factor in why I like the higher ply count tires.  Speed is less important than staying on the track the entire race.  Our win at Midnight Mayhem is good example of this concept.  We weren't the fastest, but we never left the track except for re-fueling.


Posted By: collinskl1
Date Posted: Dec/13/2010 at 8:37am
Originally posted by dillon_b12 dillon_b12 wrote:


For me, yes I think the added weight is worth it.  I've seen entirely too many tires ripped off wheels, punctured, or cut.  Peace of mind is a big factor in why I like the higher ply count tires.  Speed is less important than staying on the track the entire race.  Our win at Midnight Mayhem is good example of this concept.  We weren't the fastest, but we never left the track except for re-fueling.
 
Dillon is absolutely correct here.  It's the same concept as when you're in the air you aren't going faster, if your tires are spinning you aren't getting full traction, you can't win the race on the first lap but you sure can lose it, etc.  I'll sacrifice a little weight for a lot of robustness any day of the week.  In my opinion wheels and tires are a great place to shave weight, but there is a fine line to be tread (no pun intended).
 


-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: tp
Date Posted: Dec/15/2010 at 2:47am
Originally posted by RonGeorge RonGeorge wrote:

Thanks guys.

@dillion and @tp,

C 489's are 2 ply 23-7-10, correct? I was certainly interested in getting a clarification on dillionb12's statement on 10-Dec-2010 at 10:46am that these tires have a softer "side bite" than forward bite. Do you think all that lateral stiffness with higher 4 and 6 ply tires is really necessary and does it warrant the weight increase you get in the tire? Also, will increasing the psi's in your tire reduce side bite in any way to get the same effect as reducing ply's (just asking)? And finally, how much of a weight difference is there between a 2 and a 4 or 6-ply tire? 


Now we're going from Tire 101 to Tire 202. The weight difference in ply is going to depend on the construction of the tire. A little brief on tire construction: a ply is the layer of fabric that is laid into the rubber while the tire is being molded. So in a lot of cases more plies are heavier. But as pointed out the Maxxis Razr2 is a 6 ply and doesnt weigh much more than a 2 ply Carlisle. Just depends on what is used to construct each ply. A lot of the new high performance tires are using kevlar.

I'm not sure about your question on increasing PSI. The number of plies really isn't going to determine the side bite of a tire. Bumping up the pressure will increase how stiff a tire is. This can help protect the wheel lip, but there are a whole other set of things that you have to worry about by doing that. It will change the size of your contact patch which will change how your car will handle. Also increasing the PSI will put more force on the bead meaning you're more likely to blow it off. 


-------------
-Tom

Oregon State BajaSAE Team Captain


Posted By: CLReedy21
Date Posted: Dec/15/2010 at 5:20pm
Anybody want to throw radial vs bias ply into the mix?

-------------
-Chris Reedy
TTU Alumni
Fourwheeler Drawer



"Quick with the hammer, slow with the brain."


Posted By: tp
Date Posted: Dec/15/2010 at 5:35pm
You're just trying to make me work.

-------------
-Tom

Oregon State BajaSAE Team Captain


Posted By: collinskl1
Date Posted: Dec/16/2010 at 8:28am

I don't know much about the ATV world, but are there really many bias ply tires that small?  I know in the truck/rock crawling world bias tires are sometimes more desireable because they are not as stiff and can conform to obstacles better.  I'm not certain if that would be a good thing at high(er) speeds and terrains baja cars encounter.



-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: dillon_b12
Date Posted: Dec/16/2010 at 1:44pm
Originally posted by collinskl1 collinskl1 wrote:

I don't know much about the ATV world, but are there really many bias ply tires that small?  I know in the truck/rock crawling world bias tires are sometimes more desireable because they are not as stiff and can conform to obstacles better.  I'm not certain if that would be a good thing at high(er) speeds and terrains baja cars encounter.


Actually, until recently, almost all ATV tires were bias-ply.


Posted By: collinskl1
Date Posted: Dec/16/2010 at 2:43pm
Well my ignorance can be explained by my lack of insight into ATV stuff until my baja involvement Wink
 
Without testing this is all speculation, but I'm not sure I would want to lose the internal stiffness of a higher ply tire.  As mentioned in the "bottomed out" thread by Chris, our tires flex A LOT on impacts.  I like my wheels to be as round as possible!  I also like having predictable handling afforded by lateral stiffness of the sidewall and only relying on the tread "un-side-bite-ness" to be able to slide around a corner rather than the sidewall rolling over so the contact patch is no longer located on the center of the tread but the edge lugs.
 
 


-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: tp
Date Posted: Dec/16/2010 at 2:47pm
Rather than write up something nice and long about bias-ply and radials, this guy here does a pretty good job of describing the differences:

http://www.mud-throwers.com/bias_vs_radial_tires

Tires like the BF Goodrich Baja TA are of radial construction whereas something like an Interco TSL is a bias-ply. Two different uses- two different tires.


-------------
-Tom

Oregon State BajaSAE Team Captain


Posted By: collinskl1
Date Posted: Dec/16/2010 at 2:55pm
They make radial swampers too...Geek

-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: tp
Date Posted: Dec/16/2010 at 2:58pm
Originally posted by collinskl1 collinskl1 wrote:

They make radial swampers too...Geek


Yeah yeah I know Smile. But people also use swampers for street rigs.


-------------
-Tom

Oregon State BajaSAE Team Captain


Posted By: p.lewis
Date Posted: Dec/16/2010 at 5:08pm
Originally posted by tp tp wrote:

Rather than write up something nice and long about bias-ply and radials, this guy here does a pretty good job of describing the differences:

http://www.mud-throwers.com/bias_vs_radial_tires

Tires like the BF Goodrich Baja TA are of radial construction whereas something like an Interco TSL is a bias-ply. Two different uses- two different tires.
 
Thanks for the link!


Posted By: Red_Beard
Date Posted: Dec/16/2010 at 7:16pm
Originally posted by collinskl1 collinskl1 wrote:

They make radial swampers too...Geek


They suck ass...  I would rather go through 10 sets of bias swampers before buying another set of those piles of crap.


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SDSM&T 09-10 Team Lead
2nd & 9th Baja West

Project Engineer
Matrix Service - Bellingham, WA


Posted By: collinskl1
Date Posted: Dec/16/2010 at 8:18pm
Which is why they really aren't a good idea.  They suck off road for anything but mud because of how stiff they are, and they're too aggressive for on road use... It would be better to have two sets of tires. 
 
Annnnyways, back on topic: Has anyone tuned tires?  Like taking a grooving iron to a set to change the tread pattern?


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Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: CLReedy21
Date Posted: Dec/16/2010 at 8:41pm
We used to groove the old 27lb terras, but we've moved past that a little.

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-Chris Reedy
TTU Alumni
Fourwheeler Drawer



"Quick with the hammer, slow with the brain."


Posted By: Red_Beard
Date Posted: Dec/17/2010 at 7:22am
Originally posted by collinskl1 collinskl1 wrote:

Which is why they really aren't a good idea.  They suck off road for anything but mud because of how stiff they are, and they're too aggressive for on road use... It would be better to have two sets of tires. 
 
Annnnyways, back on topic: Has anyone tuned tires?  Like taking a grooving iron to a set to change the tread pattern?


Yes I have and got some very good results from it.  I found that there are certain types of soils and soil conditions that lend themselves to extremely grooved tires, and others that lend themselves to standard tread patterns. 


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SDSM&T 09-10 Team Lead
2nd & 9th Baja West

Project Engineer
Matrix Service - Bellingham, WA


Posted By: collinskl1
Date Posted: Dec/17/2010 at 7:45am
I always struggled with the fact that we had to predict the conditions and track style (for the most part) months in advance.  I guess you could take multiple sets and make a final choice before tech inspection on site...  This is why I always defaulted to standard mudlites; because they're light, aggressive, great in soupy conditions, and as good as anything (barring maybe Terras or other farm implement tread) in water.

-------------
Kyle Collins
Lipscomb University Alumni
2x Project Manager

Nexteer Automotive
Product Engineer, Electronic Power Steering

... and the 8th simple machine: a bigger hammer.


Posted By: rohanlakhotia46
Date Posted: Mar/14/2011 at 12:33pm
our team has been facing a few problems regarding the wheel's nut. Apparently the nut used here is tapered and is the one generally used in normal passenger cars in India. 
The diameter of the hole on the Hub is slightly smaller than the corresponding hole of the rim.
Hence a Tapered Nut has been used for the same to provide a proper fastening system, as shown in the pictures.

However we don't have tapered lock nuts available in India. I wanted to know if we are allowed to loctite over there or is there any other solution? We are also thinking of using a cotter pin after drilling through holes in the bolt and nut.





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Rohan Lakhotia

`The 46 Doctor`

http://www.teamjaabaz.com" rel="nofollow - TEAM JAABAZ

Vellore Institute Of Technology

vellore,t.n., INDIA

Car #42 (kansas)


Posted By: tech.tmr11
Date Posted: Mar/14/2011 at 12:47pm
last time we used locknuts....no problem with that.... 

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TEAM MANIPAL RACING
INDIA


Posted By: tp
Date Posted: Mar/14/2011 at 1:16pm
Originally posted by tech.tmr11 tech.tmr11 wrote:

last time we used locknuts....no problem with that.... 


Using a normal nut when you need a tapered one would be inviting disaster. Your wheel would never be concentric.

One option if you need tapered lock nuts is to make tapered washers and the use a normal lock nut. Wouldn't be too hard to drill out a tapered nut and cut it down to turn it into a tapered washer.

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-Tom

Oregon State BajaSAE Team Captain


Posted By: Akron 1998 to 2004
Date Posted: Mar/14/2011 at 2:52pm
Wheels:  I'm guessing its because of price but I'm a bit surprised we were the only Baja team that seemed to us Keizer Wheels.  They are heavily used in SAE Formula.  If you can find a Douglas rim in the size you need, they're cheaper.  But for a little more $ Keizer will make a rim in any bolt pattern, diameter, width, back spacing you want.  You can get absolutely zero scrub radius with custom back spacing!  Don't know what the current pricing is like but a custom rim with dent rings and mud cover cost about $120 back in the day.
 
http://keizerwheels.com/ - http://keizerwheels.com/
 


Posted By: tp
Date Posted: Mar/14/2011 at 3:41pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Wheels:  I'm guessing its because of price but I'm a bit surprised we were the only Baja team that seemed to us Keizer Wheels.  They are heavily used in SAE Formula.  If you can find a Douglas rim in the size you need, they're cheaper.  But for a little more $ Keizer will make a rim in any bolt pattern, diameter, width, back spacing you want.  You can get absolutely zero scrub radius with custom back spacing!  Don't know what the current pricing is like but a custom rim with dent rings and mud cover cost about $120 back in the day.
 
http://keizerwheels.com/ - http://keizerwheels.com/
 

With the demands of todays racers, you can get a Douglas wheel in almost any backspacing that you can dream of. Not only that, but personally I don't know how much I'm going to trust a road wheels with what we do. I've seen our Formula team break wheels. Judging by how many wheels I've destroyed, Baja just demands something stronger.

If you have a properly designed suspension, you can get a zero scrub radius with whatever wheel you choose. Like maybe something off the shelf.

EDIT- didn't realize that Keizer makes quad wheels too. Thought it was just sprint car and road wheels.


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-Tom

Oregon State BajaSAE Team Captain


Posted By: ErikHardy
Date Posted: Mar/14/2011 at 5:04pm

Along the lines of what tp said, would there be enough material to put the lugnut in the lathe and put a small taper on the end of it.



Posted By: tp
Date Posted: Mar/14/2011 at 5:08pm
Most tapered lugs are 37 degrees (I believe). You would need a pretty massive lock nut to put that sort of taper on it.

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-Tom

Oregon State BajaSAE Team Captain


Posted By: Akron 1998 to 2004
Date Posted: Mar/14/2011 at 5:17pm
Originally posted by tp tp wrote:

With the demands of todays racers, you can get a Douglas wheel in almost any backspacing that you can dream of. Not only that, but personally I don't know how much I'm going to trust a road wheels with what we do. I've seen our Formula team break wheels. Judging by how many wheels I've destroyed, Baja just demands something stronger.

If you have a properly designed suspension, you can get a zero scrub radius with whatever wheel you choose. Like maybe something off the shelf.

EDIT- didn't realize that Keizer makes quad wheels too. Thought it was just sprint car and road wheels.
 

Douglas wheels are almost all spaced 3" in from the outside.  Keizer will make you one spaced 0".  That means your custom A-arms can be 3" longer, better angle on the ball joints, more travel, what ever you want to design, etc.  Keizer makes nice spun metal race quad wheels.  Never damaged one with a anti-dent ring.



Posted By: ErikHardy
Date Posted: Mar/14/2011 at 5:17pm
Originally posted by tp tp wrote:

Most tapered lugs are 37 degrees (I believe). You would need a pretty massive lock nut to put that sort of taper on it.
 
I misread what he was talking about, I thought he had a flat lugnut and just needed a tapered end, my mistake.


Posted By: tp
Date Posted: Mar/14/2011 at 5:57pm
You can backspace Douglas wheels 1, 2, 3, 4, 4.5 or 5 inches. The problems is if you got too much one way or the other you end up putting lots of stress on your wheel bearings.

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-Tom

Oregon State BajaSAE Team Captain


Posted By: dillon_b12
Date Posted: Mar/14/2011 at 6:19pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by tp tp wrote:

With the demands of todays racers, you can get a Douglas wheel in almost any backspacing that you can dream of. Not only that, but personally I don't know how much I'm going to trust a road wheels with what we do. I've seen our Formula team break wheels. Judging by how many wheels I've destroyed, Baja just demands something stronger.

If you have a properly designed suspension, you can get a zero scrub radius with whatever wheel you choose. Like maybe something off the shelf.

EDIT- didn't realize that Keizer makes quad wheels too. Thought it was just sprint car and road wheels.
 

Douglas wheels are almost all spaced 3" in from the outside.  Keizer will make you one spaced 0".  That means your custom A-arms can be 3" longer, better angle on the ball joints, more travel, what ever you want to design, etc.  Keizer makes nice spun metal race quad wheels.  Never damaged one with a anti-dent ring.


Douglas wheels can be had in 4+1 as well as the standard 3+2 offset.

I e-mailed Keizer near the end of '08 for some pricing so I'm not sure how current this is:

Originally posted by dillon_b12 dillon_b12 wrote:

Here is the e-mail I received from Keizer.  These prices are for 4x156 Yamaha(for fronts) and 4x110 Honda(for rears).  I believe this is also in an .125" thickness.  Too spendy for me.
 
"Your front proring wheels will be 2pc,   run aprox $155.
The rear would be a 3pc wheel.   Aprox $185
This would be a proring wheels.  Strengthening ring to the outside.  Sweet
wheel.   
For $20 more you can add a mudcover to the wheel. 

Our strength is superior as it is 6061 T6 parts with no shortcuts.
Attached is our front wheels with a front hubs mounted in it.
 
Wade"

Current pricing for Douglas wheels:

10x5 Wheel
3+2 Offset
4/156 Bolt Pattern  (This is a Yamaha Raptor wheel.)

Blue Label(.125): $58.00
Black Label(.160): $68.00
Red Label(.190): $77.00


Posted By: Greenreed1936
Date Posted: Mar/14/2011 at 10:22pm
We have run Keizer wheels for the last 5 or so years and just now had one destroy itself at Michigan Tech's Winter Comp.

They hold up to the abuse quite well.  A little spendy but perform very well.


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SDSMT BAJA SAE


Posted By: SDTech
Date Posted: Mar/14/2011 at 10:36pm
Originally posted by Greenreed1936 Greenreed1936 wrote:

We have run Keizer wheels for the last 5 or so years and just now had one destroy itself at Michigan Tech's Winter Comp.

They hold up to the abuse quite well.  A little spendy but perform very well.


To be fair, that wasn't really the fault of the wheel...


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SDSMT Baja SAE
Car #'s 4 & 6 - Oregon
Car # 14 - Wisconsin

#4 & #79 - Western Washington

2010-2011 SDSM&T Team Lead


Posted By: Greenreed1936
Date Posted: Mar/14/2011 at 11:01pm
Originally posted by SDTech SDTech wrote:

Originally posted by Greenreed1936 Greenreed1936 wrote:

We have run Keizer wheels for the last 5 or so years and just now had one destroy itself at Michigan Tech's Winter Comp.

They hold up to the abuse quite well.  A little spendy but perform very well.


To be fair, that wasn't really the fault of the wheel...


Well thats true.  You were driving  LOL


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SDSMT BAJA SAE


Posted By: Akron 1998 to 2004
Date Posted: Mar/15/2011 at 9:54am
Originally posted by tp tp wrote:

You can backspace Douglas wheels 1, 2, 3, 4, 4.5 or 5 inches. The problems is if you got too much one way or the other you end up putting lots of stress on your wheel bearings.
 
Where do you get your Douglas wheels from?  I'll need to buy some soon.  I need this:
 
4/4 10X6 1.0 + 5.0    0.190 (red label?)
 
Thanks


Posted By: CLReedy21
Date Posted: Mar/15/2011 at 6:53pm
You're probably gonna find that one under the "call" section.

-------------
-Chris Reedy
TTU Alumni
Fourwheeler Drawer



"Quick with the hammer, slow with the brain."


Posted By: Akron 1998 to 2004
Date Posted: Mar/18/2011 at 12:16pm
Just in case any one is interested.
 
They cost $140.
 
 


Posted By: ballast
Date Posted: Sep/30/2012 at 4:20am
anyone who has used carlisle at489 2*ply tires please share your experience . I personally think that 2ply is more prone to punctures or cuts. But my doubt is that will it get punctured even under normal conditions or only under harsh conditions. Any information will be appreciated. thankyou. 

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jacking with the screw


Posted By: Soccerdan7
Date Posted: Oct/01/2012 at 10:01am
We have used them for our rears for our last 3 competitions and the only flat we had was due to a massive impact that also dented our trailing link, bent the lower camber link pretty bad and sheared the driveshaft...

They are a great lightweight rear tire.


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Danny

Cornell

(fall'07 - spring'12)
Former Captain / MEng / that guy with all the carbon
10 races, 7 top ten's, 2 overall wins


Posted By: Bantu
Date Posted: Jul/17/2018 at 4:28pm
Does anyone knows what are the typical values of the rolling resistance,and static friction coefficient of the mini Baja tire running on the tared track/road?


Posted By: sujandinesh
Date Posted: Jul/18/2018 at 3:50am
I do not exactly know the typical values for rolling resistance of a Baja tyre but however, based on my experience, they must be in the range of 10N - 150N. Please keep in mind that rolling resistance is a function of the vertical force, inflation pressure and forward speed of the tyre and hence I have expressed it as a range. 

You can experimentally determine your tyre's static friction coefficient by using a simple spring balance. This value would be realistic and it would also have more validity during your design evaluation and car's dynamic analysis. 


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RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands


Posted By: Bantu
Date Posted: Sep/11/2018 at 5:23pm
Hi
I am working on the Mini Baja from South Africa. The total weight of the mini Baja including the weight of the baja is 310Kg. My aim is to archive the maximum velocity between the range of 50km/h-60km/h.But I only managed to archive 44km/h by calculations.
My question is, when I calculate the resistance forces, should I consider both Static friction and Rolling resistance friction? In my calculation I considered them both and I found that, the static friction has a very huge negative impact towards achieving my goal. Now I am not sure if I should take the static friction into account.


Posted By: RLM
Date Posted: Sep/12/2018 at 5:27am
The static friction of what? 

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McMaster Baja Racing (09-Dec 2015)
Team Captain 2012-2015
Suspension Lead 2015-2016
All spoonfeed PM requests will be billed at $10 USD per reply, payable via paypal.


Posted By: Bantu
Date Posted: Sep/12/2018 at 5:55am
Static friction between the Baja Tires and the surface or road. Remember the rolling friction occurs between the tires and the surface also.


Posted By: sujandinesh
Date Posted: Sep/12/2018 at 8:57am
Originally posted by Bantu Bantu wrote:

Hi
I am working on the Mini Baja from South Africa. The total weight of the mini Baja including the weight of the baja is 310Kg. My aim is to archive the maximum velocity between the range of 50km/h-60km/h.But I only managed to archive 44km/h by calculations.
My question is, when I calculate the resistance forces, should I consider both Static friction and Rolling resistance friction? In my calculation I considered them both and I found that, the static friction has a very huge negative impact towards achieving my goal. Now I am not sure if I should take the static friction into account.
There is no such thing as a rolling resistance friction. It is either expressed as a moment or a force (not preferred). The rolling resistance moment maybe one of the reasons for your decreased speed range but however I would only investigate this after going through other losses such as the transmission, air drag etc. 

I do not understand what you mean by the next highlighted statement. 


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RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands


Posted By: sujandinesh
Date Posted: Sep/12/2018 at 9:06am
Originally posted by Bantu Bantu wrote:

Static friction between the Baja Tires and the surface or road. Remember the rolling friction occurs between the tires and the surface also.
This is definitely not one of the reasons why you have a decreased speed range. I do not understand how you would use this and calculate the resistance forces. Friction is paramount for grip without which you would have 100% slip condition i.e. the tyre with a certain angular velocity but with no forward speed. 

My suggestion would be to reinvestigate the losses in your transmission. 


-------------
RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands


Posted By: Bantu
Date Posted: Sep/12/2018 at 9:59am
I hear u but my question is, which friction must I use in my calculations between static friction resistance and rolling friction resistance?


Posted By: sujandinesh
Date Posted: Sep/12/2018 at 10:15am
Are these calculations to determine the resistance to your car? Then neither. 

-------------
RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands


Posted By: Bantu
Date Posted: Sep/12/2018 at 10:54am
Yes. For example: F_static = u*N, where (u=0.4) static friction coefficient and (N=310kg*9.81) normal force. Therefore F_static = 0.4*310*9.81 = 3041.1N. And F_rolling = u*N, where (u=0.02) rolling resistance coefficient and (N=310kg*9.81) normal force. Therefore F_rolling = 0.02*310*9.81 = 60.822N.

Remember there is also an air drag resistance force that I have to add on these two forces.

My question again, do I add Air drag resistance force with rolling resistance force or Air drag resistance force with static friction resistance force or I have to add all three resistance forces in order to get the total resistance force for an accelerating Baja from rest on a flat level track??


Posted By: sujandinesh
Date Posted: Sep/12/2018 at 2:32pm
Now I get what you want to ask. 

To be honest, whether to consider the static or rolling friction coefficient is a pretty basic concept, I would suggest you rethink this and try to imagine the car as a brick or a brick with wheels. 

Coming to the second part, the air drag is an additional resistance the car faces, so it is a separate effect. 

The last part, regarding the rolling resistance, I think needs some clarification. The rolling resistance is purely a resistance offered by the viscoelastic nature of the tyre rubber to a freely rolling tyre. This is coming solely from your tyre and hence is also a separate effect. 


-------------
RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands


Posted By: Bantu
Date Posted: Sep/12/2018 at 2:47pm
Thank you for your explanations but you still have not answered my question.


Posted By: sujandinesh
Date Posted: Sep/12/2018 at 3:24pm
Originally posted by sujandinesh sujandinesh wrote:

Now I get what you want to ask. 

To be honest, whether to consider the static or rolling friction coefficient is a pretty basic concept, I would suggest you rethink this and try to imagine the car as a brick or a brick with wheels. 

Coming to the second part, the air drag is an additional resistance the car faces, so it is a separate effect. 

The last part, regarding the rolling resistance, I think needs some clarification. The rolling resistance is purely a resistance offered by the viscoelastic nature of the tyre rubber to a freely rolling tyre. This is coming solely from your tyre and hence is also a separate effect. 


-------------
RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands


Posted By: Bantu
Date Posted: Sep/12/2018 at 4:00pm
Thank you


Posted By: RLM
Date Posted: Sep/13/2018 at 7:06am
Originally posted by sujandinesh sujandinesh wrote:

Originally posted by sujandinesh sujandinesh wrote:


To be honest, whether to consider the static or rolling friction coefficient is a pretty basic concept, I would suggest you rethink this and try to imagine the car as a brick or a brick with wheels. 


This statement was where I was trying to steer the conversation, Just didn't think it would need to be this spelled out. 


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McMaster Baja Racing (09-Dec 2015)
Team Captain 2012-2015
Suspension Lead 2015-2016
All spoonfeed PM requests will be billed at $10 USD per reply, payable via paypal.



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