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Preferred CVT

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Paboaglez View Drop Down
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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 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 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 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 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 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: 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 vin2000 Quote  Post ReplyReply Direct Link To This Post 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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