General CVT tuning test

[coachgeo]

Found a good knowledgeble CVT fella named Roy who owns a new company named Quality Drive Systems. He's also dealt with Dave and his Diesel creations (Locomotivebreath on this site). It was nice to find that commonality. Unfortunately neither he nor I have heard from Dave in awhile.

anywayyyy.. back to topic

Roy's test is this. Put bike on stands so back wheel can spin freely/safely.

. Spin up to max rpm you would in use. (full throttle)
. Apply rear brakes slowly and watch RPM.
. Watch Secondary/Driven/Back clutch.
. note the RPM when braking belt pops back to position it sits at idle.
. If it RPM drop is around 100-150 rpm your weights/cams in the Primary/Drive/Front clutch are probably set about right
. If RPM drops more your weights are off.
. RPM does not drop your weights are off

Damn... now I forget if drop more means too heavy or to light of weights... crap I took bad notes. I'll follow up later.

[Curtis in Texas]

So are you saying to start tapping the brake while holding the throttle wide open and slowing down the back wheel until the rpm's fall and the belt drop off? Wouldn't going from idle and increasing the r's until the belt engages give you the same information? I am trying to learn CV's so I'm no expert. But I am staying at the Hilton in Chicago.



I hung the diesel KLR by the overhead winch and watched how the CV worked as I sped up the motor and let it off.
This showed me when it engaged, topped out to max ratio and released near idle.

All things said I'd rather have a clutch!!!!! But that's just me.


Typing with my big thumbs and calluses sucks...

[coachgeo]

So are you saying to start tapping the brake while holding the throttle wide open and slowing down the back wheel until the rpm's fall and the belt drop off? Wouldn't going from idle and increasing the r's until the belt engages give you the same information? .......

No would not be the same cause the idea is to simulate a situation where back shifting is necessary..... such as going up hill ... where your still in full throttle but the back wheel is now moving slower due to grade.

Have you had a chance to look thru Aaeon's book yet?

[Curtis in Texas]

Yes I've read through it but not memorized it because it deals more with tuning an existing system but nothing about how to create and assemble a working system from scratch. Wish it would go into the actual designing and engineering of a proper system.

It does not address any issues for the builders to tell them the best way to make one work and the wrong way so a person could determine they are doing it right or wrong..

[coachgeo]

Yes I've read through it but not memorized it because it deals more with tuning an existing system but nothing about how to create and assemble a working system from scratch. Wish it would go into the actual designing and engineering of a proper system.

It does not address any issues for the builders to tell them the best way to make one work and the wrong way so a person could determine they are doing it right or wrong..

Shoot.. that is how I saw it too. Was hoping your reading it with an eye and mindset coming from a more extensive background than I would find it more useful than my feeble brain could.