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Preferred CVT

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Post Options Post Options   Thanks (0) Thanks(0)   Quote vin2000 Quote  Post ReplyReply Direct Link To This Post Topic: Preferred CVT
    Posted: Jun/12/2018 at 12:14pm
Hmm after two years do we have any new CVT OEM in town? A lot of teams are pushing towards the custom ones but I have a feeling something will come up on the map just like AFCO shocks!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Andy.R Quote  Post ReplyReply Direct Link To This Post Posted: Jun/09/2018 at 8:06pm
I love the 2 years between replies
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RLM Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2018 at 7:52am
Free CVT? LOLOLOLOLOLOLOLOLOLOLOLOLOL This made my day LOL
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SAIKUMAR983 Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2018 at 12:00pm
still, they providing for free. If yes then tell me where I have to order
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sujandinesh Quote  Post ReplyReply Direct Link To This Post Posted: Mar/26/2016 at 10:08am
My man, no human being in the world can help you effectively tune a CVT by a mere conversation in a forum.

A lot of teams in India have used/still use Polaris. Why not contact them? 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote abishek Quote  Post ReplyReply Direct Link To This Post Posted: Mar/25/2016 at 11:36pm
how to do a cvt tuning in a polaris
can u help me with it
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Post Options Post Options   Thanks (0) Thanks(0)   Quote drvr5 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/17/2016 at 12:14am
Well, the secondary rpm increases as you accelerate. The rest is down to the magic of springs, cams, and physics
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Post Options Post Options   Thanks (0) Thanks(0)   Quote instinct Quote  Post ReplyReply Direct Link To This Post Posted: Mar/13/2016 at 5:51pm
How is it possible for CVT to remain on its engagement rpm all the time when its changing ratio from initial to final value. I think CVT changes its ratio only because of increase in its rpm....could u plz explain
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/13/2014 at 1:30pm
Originally posted by Richie_Dagger Richie_Dagger wrote:

We are putting together a P90 Primary/CVTech secondary hybrid. I believe OSU ran the same hybrid setup? I really like the P90 primary. Easy to dissemble, very tune-able, and lighter than our CVTech primary.

We ran a Polaris P90 / CVTech (heavily modified) secondary. It worked quite well for our 2010 and 2011 cars before we switched to the Gaged CVT. 

Be mindful of different belt widths, angles, etc... A hybrid can be tricky.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote paasch Quote  Post ReplyReply Direct Link To This Post Posted: Jul/11/2014 at 2:51pm
Originally posted by Richie_Dagger Richie_Dagger wrote:

We are putting together a P90 Primary/CVTech secondary hybrid. I believe OSU ran the same hybrid setup? I really like the P90 primary. Easy to dissemble, very tune-able, and lighter than our CVTech primary.

We've never run a CVTech at competition. We used Polaris 2001-2010, then switched to Gaged in 2011. We tested CVTech in 2008, but found it not as tune-able as the Polaris. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Richie_Dagger Quote  Post ReplyReply Direct Link To This Post Posted: Jul/10/2014 at 12:54pm
We are putting together a P90 Primary/CVTech secondary hybrid. I believe OSU ran the same hybrid setup? I really like the P90 primary. Easy to dissemble, very tune-able, and lighter than our CVTech primary.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/10/2014 at 10:45am

What's your goal?  Specific range of gears, tune ability, something else?  Is there a deficiency with the 780 you are trying to correct? 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote NanMohz Quote  Post ReplyReply Direct Link To This Post Posted: Jul/10/2014 at 4:14am
We are planning to use a hybrid CVT this year (Keeping our comet 780 secondary as such and buying a new primary). So have any of you guys out here have tried using hybrid's? Since many of the manufacturers provide CVT's specifically tuned for BAJA, will our option be a finer one to choose indeed?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pedro UFPBaja Quote  Post ReplyReply Direct Link To This Post Posted: Apr/02/2014 at 6:08pm
Many brazilian teams tried to tune a scooter cvts in late 90's, noone get even close to the performance of the good old comet 780 that time.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote njgedr Quote  Post ReplyReply Direct Link To This Post Posted: Apr/01/2014 at 4:12pm
I attribute the smoke to poor tuning on the clutching... probably a Dayco belt too haha. There are scooter clutches out there for around 15-17 hp. Even a scooter clutch designed to run at 5 hp can work if tuned correctly for double the hp and load. Unfortunately I can't share which clutch we are working on, but we are tuning it to handle 15 hp nearly triple what it was designed for. I would guess it is very similar to the clutch out of that smoking car. Even a centrifugal clutch will work on 10 hp, you would be hard pressed to find a cvt that can't be tuned to handle it. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Richie_Dagger Quote  Post ReplyReply Direct Link To This Post Posted: Apr/01/2014 at 11:23am
I actually thought the smoke was because a complete 2 stroke scooter engine + drivetrain was thrown into that thing! That's some pretty impressive belt smokin'.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pedro UFPBaja Quote  Post ReplyReply Direct Link To This Post Posted: Apr/01/2014 at 3:28am
Thas how a baja car runs with a scooter cvt:



The smoke is the belt frying. A baja is at least twice heavy and the engine was 3 or 4 times more torque but with 1/3 of the rpm. Absolutely incompatible.


Edited by Pedro UFPBaja - Apr/01/2014 at 3:31am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Richie_Dagger Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 2:06pm
Originally posted by njgedr njgedr wrote:

Eventually, I expect to see some scooter clutches in baja cars. They are sized perfectly for ~10 hp We are always working with them here at Gates, they are so much smaller, lighter, and simpler than the Polaris or Gaged. If anyone is interested in specifics I can try to get some scooter models they go in. The US is not a very big scooter country, I guess that is why many teams have not seen them before.

I found that CVT tuning in baja has much less effect than snowmobiles or something with a steeper torque curve. There is still value in tuning, but narrowing down on the exact weights and springs never had much effect for us. I would much rather have a smaller lower inertia CVT with less tunability. However, Laval had their CVTech figured out pretty good... unless it was just weight. I attribute the Cornell performance to launch control and weight.
If the 50cc VIP scooters they sell in town here had a big enough CVT that would be perfect. I can't go outside or on craigslist without being bombarded by dozens of those things...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Paboaglez Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 1:51pm
could you post some information of this scooter cvt?? webpage or specifications???
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Post Options Post Options   Thanks (0) Thanks(0)   Quote njgedr Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 12:47pm
Eventually, I expect to see some scooter clutches in baja cars. They are sized perfectly for ~10 hp We are always working with them here at Gates, they are so much smaller, lighter, and simpler than the Polaris or Gaged. If anyone is interested in specifics I can try to get some scooter models they go in. The US is not a very big scooter country, I guess that is why many teams have not seen them before.

I found that CVT tuning in baja has much less effect than snowmobiles or something with a steeper torque curve. There is still value in tuning, but narrowing down on the exact weights and springs never had much effect for us. I would much rather have a smaller lower inertia CVT with less tunability. However, Laval had their CVTech figured out pretty good... unless it was just weight. I attribute the Cornell performance to launch control and weight.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Paboaglez Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 12:11pm
Is easier to tune

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Paboaglez Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 12:08pm
So, in Rochester 2013, 6 of the top 10 endurace race used Gaged...

In theory is best to have a big overall ratio for our Briggs engine, like CVTech 3:1, 0.43:1 overall ideal and theorical = 6.98

But as I have read and asked; Gaged Ratios:
Gaged with 6" Drive and 8" Drive; 4:1 and 0.9:1 OR = 4.44
Gx9 3.5:1, .85:1 OR = 4.11
Gx7 3:1, .65:1 OR = 4.61

The overall ratio, (low speed ratio/ high speed ratio), in Gaged is way lower to the CVTech...

So my question is why Gaged CVT is better CVT for Bajas??

I would say:
Is lighter like 30%
High efficiency
the low speed ratio is bigger than CVTech
all above

I am not sure, so maybe you can help me, do someone has data about it (efficiency and real ratios)

Thank you in advance
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pedro UFPBaja Quote  Post ReplyReply Direct Link To This Post Posted: Jun/26/2013 at 11:39pm
...


Edited by Pedro UFPBaja - Apr/03/2015 at 1:29pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mohit Saini Quote  Post ReplyReply Direct Link To This Post Posted: Jun/26/2013 at 10:20pm
sir, thanx for responce. but not i am asking about cvt's not about time measuring accesories

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Post Options Post Options   Thanks (0) Thanks(0)   Quote JeremyB Quote  Post ReplyReply Direct Link To This Post Posted: Jun/24/2013 at 2:59pm
FWIW, I'll throw out an updated nugget. Top ten endurance cars @2013 RIT
 
1 - Custom
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: May/23/2013 at 3:22pm
Originally posted by DrewT DrewT wrote:

The downside to the Comet was always heat.  We burned up belts fast, and sometimes melted all the plastic friction pads out of the secondary ramps.  In Peoria in 08, we changed 2 or 3 belts during endurance and finished 2nd (before being disqualified in post race tech).  In Oregon in 09, we changed 4 belts during endurance, melted the plastic friction pads in the secondary, and even heated up the secondary snap ring so hot it popped out of the groove and let the secondary back sheave grind into our gearbox.
 
I've been running the same Comet 790 for 13 years, I only changed the belt because it looked dirty and I had a new one.  You probably needed to increase (not decrease) the spring tension on the secondary to prevent belt slip and possibly a different gear ratio. 
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ballast Quote  Post ReplyReply Direct Link To This Post Posted: May/23/2013 at 12:20pm
QDS still offers comet CVT at a discounted price for universities.  call Roy at QDS and ask him for a catalogue. mails usually attract a very long response time. I prefer phone calls.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote DrewT Quote  Post ReplyReply Direct Link To This Post Posted: May/23/2013 at 6:00am
We always ordered the Comet 790 series from QDS that was already tuned for a briggs and stratton.  I'm not sure if QDS even offers the comet anymore, I had heard comet went out of buisness, but at the time it was the hot ticket for teams that wanted an out of the box setup that worked well.  One year we put a lot of effort into tuning it and trying different combinations of weights, ramps, springs, belts, c-c distances, and pulley offsets.  We validated the tests with both timed acceleration runs and some pulls on the rolling road dyno (the dyno didn't give very realistic numbers for our low-power application, but it did give a very good indication of relative performance compared with the other setups we tried, and you could get right up to the cvt as it was working to see how it shifted).  What we found was that QDS had already done a very good job setting up the comet for Baja SAE.  We ended up going down one spring rate on the secondary and leaving the primary stock for the best results.
 
The downside to the Comet was always heat.  We burned up belts fast, and sometimes melted all the plastic friction pads out of the secondary ramps.  In Peoria in 08, we changed 2 or 3 belts during endurance and finished 2nd (before being disqualified in post race tech).  In Oregon in 09, we changed 4 belts during endurance, melted the plastic friction pads in the secondary, and even heated up the secondary snap ring so hot it popped out of the groove and let the secondary back sheave grind into our gearbox.  In Washington in 2010, we adjusted the c-c distance and pulley offsets and introduced better air circulation to the cvt cover to alleviate the heat problem somewhat, but gave up initial performance to do it; we ran the entire endurance on one belt and finished 8th, but we still melted the plastic pads on the secondary ramps by the end.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote MelkMan Quote  Post ReplyReply Direct Link To This Post Posted: May/22/2013 at 11:43am
Hi guys

I would just like to know if anyone has a reliability rating for the whole CVT system? Specifically the Polaris P-90 , but any other will do. So eg. 90% reliability etc

Thanks in advance

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Post Options Post Options   Thanks (0) Thanks(0)   Quote njgedr Quote  Post ReplyReply Direct Link To This Post Posted: May/20/2013 at 9:06am
The biggest issue with running the wrong CC Distance is not reaching the high and low capabilities of the CVT. If your CC distance is short. The Primary wont grab until it is shifted farther in, taking away from your low ratio. Also, when the primary is fully shifted in, you will not be shifted fully out on your secondary, taking away from your High Ratio. 

The same issues are true with a CC distance that is too long just opposite, 
Low: The Secondary will be partially shifted out at Idle.
High: The Primary cant shift Fully in because the secondary is all the way open

I recommend using an Aluminum plate mounted to the mounting bolts around the output of the briggs, and the input of your transmission, to maintain good CC tolerances, and alignment. 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rishabh Quote  Post ReplyReply Direct Link To This Post Posted: May/20/2013 at 8:03am
We did shift the FNR while CVT was idling, and we didn't have friction clutches. The engagement was not smooth but it worked for about two months, Right before the event the we had engagement problems of the reverse,we corrected it but during the maneuverability event we had to engage the reverse gear a lot of times during turns( steering design was not proper,high turning radius). Eventually we couldn't run the endurance, the shifting mechanism completely failed.The engagement of reverse without the clutch puts extra load on the shifting mechanism which leads to failure of the components.
One solution is to shift the below the engagement speed of the CVT that is when the belt is not transmitting torque. I haven't checked it's practical feasibility plus the members mention it's difficult to calculate the engagement speed considering all the parameters. CVTECH sponsored CVT which we use gives the engagement loads of drive pulleys.So that information might help us next time. Friction clutches have no reliability issues for sure and worked fine 2 years back in the event.
   


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: May/19/2013 at 3:28pm
Yes, it will effect the idle behavior, but we found it very difficult to get anywhere near the full shift out running it per the manufacturer's spec. I can only imagine that running it substantially closer would enhance this problem and also delay shift out behavior and lengthen the amount of time the belt is slipping.

We ran the CVTech with minimal mods in 2009 in this way and had a very fast car... the only drawbacks were additional heat in the casing and belts wanting to wear out faster. Ever since then the Cornell team has not run a very close to stock setup, so comparisons are difficult.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ballast Quote  Post ReplyReply Direct Link To This Post Posted: May/19/2013 at 3:15pm
Originally posted by Soccerdan7 Soccerdan7 wrote:

and you want to be slightly over the manufacturer's number rather than be under.

For the 242 mm example, I would saw you want to be in the 242-245mm range
Just curious to know why you'd prefer to be slightly over than the mfr specified c-c than be under it. Wont it put some extra tension on the belt and affect idling behavior of the vehicle.

Btw i went through the other threads regarding c-c distance but did not get what i was looking for.But thanks anyway dude..Tongue
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: May/19/2013 at 11:18am
Originally posted by ballast ballast wrote:

what will be the effect if the CVT c-c distance falls short of what is specified by the manufacturer i.e., if the specified c-c distance of a belt is 242mm but while assembling, you get only like say 235mm, what would be the effect on performance.


This would be very bad. Center-center distance is something you want to be able to precisely set and maintain, and you want to be slightly over the manufacturer's number rather than be under.

For the 242 mm example, I would saw you want to be in the 242-245mm range. There is a thread on here somewhere that discusses the effect of c-c distance specifically.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ballast Quote  Post ReplyReply Direct Link To This Post Posted: May/19/2013 at 2:03am
what will be the effect if the CVT c-c distance falls short of what is specified by the manufacturer i.e., if the specified c-c distance of a belt is 242mm but while assembling, you get only like say 235mm, what would be the effect on performance. Also is it possible to shift a FNR while CVT is idling, without using a friction clutch like in manuals??
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rishabh Quote  Post ReplyReply Direct Link To This Post Posted: May/18/2013 at 4:42am
I have a CVTech's sponsored CVT. We tried our hands to tune it last year but didn't the desired results as expected.I have read the clutch tuning handbook plus the discussions in forums related to the CVT. Just wanted to know the parameters of the CVTech's CVT that I can play with. Weights, pressure springs are the two which I can identify at present.We have 3 pressure springs and 1 set of weights which we got from CVTech. I think the CVTech doesn't offer weights and springs of different ranges which other brands do(polaris,comet).So is it advisable to make our own weights of similar profile as stock weights. Do baja teams do that ??I just need an insight to get things started.   



Edited by Rishabh - May/18/2013 at 4:45am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: May/17/2013 at 3:53am
From what i know, the other models are way overbuilt for our use and much heavier too.
The driven are a lot bigger and give you less ratio than the one in the sponsorship.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ballast Quote  Post ReplyReply Direct Link To This Post Posted: May/15/2013 at 9:20am
We have been using CVTech CVT procured through scholarship program for the last two years and managed to get decent results. Now i am eyeing on the CVTech models that does not come under scholarship. But the problem is choice. There are like 4 driver and 4 driven pulleys. I have a problem in deciding which combination would actually work. Guys, if anyone has experience in using unconventional CVTechs please share your knowledge, because the CVTech guy is not really helping. I want to know if trying them is even a worthy attempt or should i just stick to the basic model.
jacking with the screw
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Post Options Post Options   Thanks (0) Thanks(0)   Quote TaLampe77 Quote  Post ReplyReply Direct Link To This Post Posted: May/07/2013 at 3:19pm
Originally posted by jeiB jeiB wrote:

So apparently they are a lot of jr dragster cvt that I didnt know about !

  1. Shockwave clutchs by jr race car (http://www.jrracecar.com/pages.asp?pid=5)
  2. Polar ATAC (http://www.polarracing.com/catalogue/index.html)
  3. Supreme Tool clutch (http://supremetoolinc.com/cart/junior-dragsters-c-22.html?zenid=4d1710aa137da8fe1daf2426984f052a)

Anymore?

Now my question is: Is it really worth it spending 1000$ for these?

Looking at the results from 2010 in

Carolina accel event







1

Universidade de Sao Paulo

4.675

comet

2

Universite Laval

4.709

cvtech

3

Centro Universitario Da FEI

4.718

cvtech/polaris hybrid

4

Instituto Maua de Tecnologia

4.734

comet

5

Tennessee Tech Univ

4.838

gaged

6

Ecole De Technologie Superieure

4.892

cvtech

7

Univ of Maryland - College Park

5.015

gaged/polar hybrid

8

LeTourneau Univ

5.022

?

9

Universidad De La Salle Bajio

5.033

?

10

Universite de Sherbrooke

5.093

cvtech





Washington accel event







1

Universite Laval

4.957

cvtech

2

Univ of Maryland - College Park

5.018

gaged/polar hybrid

3

Ecole De Technologie Superieure

5.048

cvtech

4

Univ of Wisconsin - Madison

5.099

gaged?

5

Univ of Maryland - Baltimore County

5.151

?

6

Wichita State Univ

5.192

Polaris/Team

7

South Dakota Sch of Mines & Tech

5.242

comet

8

North Carolina State Univ - Raleigh

5.263

gaged

9

Oregon State Univ

5.273

polaris

10

Univ of South Florida

5.282

gaged

 

Im not sure about some of the teams cvts. I can modify the post if someone knows.

 EDIT: updated list


EDIT: Updated List
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Manlone Quote  Post ReplyReply Direct Link To This Post Posted: May/07/2013 at 9:33am
Thanks bro  Big smileBig smile
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: May/06/2013 at 3:15pm
This is the model currently offered to students
Info is in the form available below:


Nicholas Lefebvre

Universite Laval
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Manlone Quote  Post ReplyReply Direct Link To This Post Posted: May/06/2013 at 2:47pm
Guys I have got an old CVTech CVT from my garage. I think my seniors used that. Me and my current teammates do not know the model and the specifications of the CVT like centre to centre distance, low and high ratio. I am attaching some photos of the CVT, can anybody tell me something about it?

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/25/2013 at 1:05pm
Originally posted by Ayrton-de-Pegasus Ayrton-de-Pegasus wrote:

whatever money we are gonna need is from our own pocket.
so please guide us...
 
CVTech has a SAE Baja sponsorship program with a CVT gear specifically for the competition at a cheap price. Like $200.  I have no experience with it.
 
Comet Model 790 (Low 3.38 High 0.54) is my Preferred CVT. About $700.  
Comet Model 780 (Low 3.71 High 0.69)
Comet Model 770 (Low 3.95 High .76)
Get it from QDS  P.O.  BOX 6910 , ALHAMBRA , CALIFORNIA  91802 TEL. ( 626 ) 293-5770 
They also sell F-N-R and other stuff to SAE Baja at discount.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote cujdubs Quote  Post ReplyReply Direct Link To This Post Posted: Apr/25/2013 at 10:52am
The first thing you should do is search the forum for other threads about clutch selection. There are many and they will provide you with some good places to start
John Hannum
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/25/2013 at 10:37am
No it is a dumb question. It all depends on what you want, what you can tune, what ratios you need, etc.

The commonly used ones are:

CVTech
Polaris (P90?)
Comet (I don't know the model)
Gaged Engineering GX7 or GX9
Team Industries
Polar

Do some research and come back when you have an intelligent, specific question to ask.

Danny

Cornell

(fall'07 - spring'12)
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10 races, 7 top ten's, 2 overall wins
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ayrton-de-Pegasus Quote  Post ReplyReply Direct Link To This Post Posted: Apr/25/2013 at 8:16am
Yeah, for the greats in this filed, like you, will find this question dumb, and i am really sorry, that my question is  dumb towards you.
but for a first-timer like me and my team, even selecting a bolt and the required dimension is a big thing. and we are here to learn.
please guide us.
and here in india we dont have any FNR options.
so we are planning to import one.
and to import, whatever money we are gonna need is from our own pocket.
so please guide us...
Flying Horse...!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote collinskl1 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/25/2013 at 8:10am
No.

This is a dumb question and  you are in the WRONG SECTION!
Kyle Collins
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... and the 8th simple machine: a bigger hammer.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ayrton-de-Pegasus Quote  Post ReplyReply Direct Link To This Post Posted: Apr/25/2013 at 7:58am
hello everyone,
i am a BAJA enthusiast, and am doing Baja for the first time.
could you please help me out to select a good CVT??Smile
 
mod note: merged to this thread. post originally placed in a competition subforum


Edited by Mod Squad - Apr/25/2013 at 11:43am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: May/04/2012 at 12:30pm
http://www.polarissuppliers.com/sae_team/faq.htm

"· What is the overall ratio of the P90 clutch?
· The ratio starts near a 3.83:1 underdrive and will top out near a 0.76:1 overdrive."


Remember that you have to make modifications to the Polaris driver to fit on the Briggs engine.

· How should we mount the P90 clutch to our engine?
· I would recommend boring the clutch to the correct diameter and depth (1” dia X approx. 3.75” depth) and then broaching the ¼” keyway. The 1” bore will not clean up the entire original taper, but if you hold the diameter tightly, you will have plenty to pilot on. I like this method better than making an adapter or modifying the crankshaft.
Jeremie B.
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minibaja.mcgill.ca
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kumar Kislay Quote  Post ReplyReply Direct Link To This Post Posted: May/04/2012 at 12:23pm
I am considering using a polaris CVT. But the problem arising is that polaris wont disclose the gear ratios for its trans-axle and according to our calculation estimate we need a max gear reduction of 40-45 for the hill climb test where a 45 degree incline will be present. If you have any idea of polaris CVTs and their compatible gearbox , please let me know :)
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