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CVTech cvt disassembly

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Karthikeyan View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Karthikeyan Quote  Post ReplyReply Direct Link To This Post Topic: CVTech cvt disassembly
    Posted: Mar/31/2014 at 1:31am
We have opened the driver and were able to change the weights, didn't know how to remove the orange cap to change the primary spring. we don't have a compression tool and were not able to take off the snap ring in the driven. Is there any manual available?? please help 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 2:34am
Well for the driver you can have someone step on a box on the cap, it worked fine for us. Just a bit sketchy.
You could build a tool made of threaded rod and nuts, works too for both pulleys.
Nicholas Lefebvre

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Karthikeyan View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Karthikeyan Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 3:36am
I am not able to visualize how to use the tool.Is it like putting the threaded rod through the driven sheave and tighten it using a nut so that it compresses and we can remove the snap ring?
Sorry if i have misinterpret if anyone can post a picture, would be really helpful.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote hsnorris Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 4:50am
I have done it two ways, by using a press and just compressing the orange piece down and removing the ring.  The more desperate way I did it was by using a large C-clamp and a washer that was slightly smaller than the orange spacer as well as a flat piece of metal for the other side of the clutch.  I fitted that washer right over the orange piece and then just tightened the clamp down.

While we're on the subject I can't find any info as to what hole does what as far as spring preload is concerned in the secondary.  It's at stock right now but I'd like to decrease the preload a little bit.
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Karthikeyan View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Karthikeyan Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 11:11pm
Thanks for the input. We used a drill press, could easily press down the orange cap and could remove the ring.
The shims were moving through the spring, also could not understand their use. We faced difficulty in aligning back the spring together. Is it the same with others?
Yet to figure out how to remove the ramp from the driven sheave.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/31/2014 at 11:57pm
The shim is used as a stopper on the top end of the shift
For the cam on the driven, press down the cam and remove the snap ring
Nicholas Lefebvre

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Karthikeyan Quote  Post ReplyReply Direct Link To This Post Posted: Apr/16/2014 at 3:22pm
Can the amount of top end shift be varied by changing number of shims used? I have tried tuning my CVT, but for whichever combination I have tried, my driver sheave was not  fully shifting. (ie my belt was not riding high on top of driver).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote hsnorris Quote  Post ReplyReply Direct Link To This Post Posted: Apr/16/2014 at 3:37pm
Are the clutches aligned?  Meaning is the offset correct?  Are you testing with the wheels in the air for no load other than the drivetrain?  
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Karthikeyan Quote  Post ReplyReply Direct Link To This Post Posted: Apr/16/2014 at 4:16pm
The clutches are aligned correctly and for no load condition the shift happens fully.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote njgedr Quote  Post ReplyReply Direct Link To This Post Posted: Apr/17/2014 at 8:16am
Check your Center to Center distance
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Post Options Post Options   Thanks (0) Thanks(0)   Quote coachgeo Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2014 at 1:07pm
Originally posted by njgedr njgedr wrote:

Check your Center to Center distance
how might that affect not getting to the top of the gear ratio? You thinking belt to tight due to CC being to large for the belt's CC parameter or?


Edited by coachgeo - Apr/30/2014 at 1:22pm
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Karthikeyan View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Karthikeyan Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2014 at 1:33pm
I have checked the c-c distance, couldn't find a error. What other parameters could cause this?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote zglazer Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2014 at 2:56pm
Shifting occurs as a result of the centrifugal forces of the weights pushing against the ramps counteracting the resistive forces of the springs in the driver and driven pulleys. If you are unable to reach full shift with a particular tuning, you need to alter your tuning to either increase the centrifugal force (increase weight, change ramp angles, increase the engine RPM - naturally, not possible in baja) or decrease the spring force (switch to a lighter linear spring in the driver and/or torsion spring in the driven, reduce the preload on one or both of the springs, change the helix angles in the driven pulley).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote njgedr Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2014 at 3:55pm
Picture if the the C-C is correct and the belt is shifted all the way out on the Driver. The Belt will also ride at the bottom of the Driven, giving you maximum overdrive. No picture if the Driven moves closer to the Driver, the belt will not be as deep into the driven pulley giving you a lower overdrive. 

The same is true for if the C-C is too far. The belt will bottom out on the Driven before the Driver again giving you a lower Overdrive. 

You also lose under drive ratio too. C-C is very critical to performance at upper and lower ranges. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote coachgeo Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2014 at 10:02pm
Originally posted by njgedr njgedr wrote:

Picture if the the C-C is correct and the belt is shifted all the way out on the Driver. The Belt will also ride at the bottom of the Driven, giving you maximum overdrive. No picture if the Driven moves closer to the Driver, the belt will not be as deep into the driven pulley giving you a lower overdrive. 

The same is true for if the C-C is too far. The belt will bottom out on the Driven before the Driver again giving you a lower Overdrive. 

You also lose under drive ratio too. C-C is very critical to performance at upper and lower ranges. 
mucho thank you for that simple explanation!!!
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