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I am not an expert by any means, but I have quite a bit of experience with this type of clutch system (CVT). The clutch in your video that is bolted directly to the crankshaft is called the "driver" also known as the primary. The clutch on the T-20 is called the "driven clutch" or the secondary. As the RPM's increase, the belt goes up the driver and down the driven and this allows the gear ratio to change. Your belt is only climbing halfway up the driver so you are not getting the full range. Shimming the motor will probably correct this as 2" of deflection is too much. Rule of thumb is 1" of deflection. My machine gets the belt about 3/4 of the way up the driver, but if I manually override the governor, it goes all the way to the top. I just need to find a way to modify the governor on mine. Your problem could be solved by simply shimming the motor. Best of luck with it and let us know how it works out. I'm sure others will chime in with their .02. RR
I just looked at your video again. You can actually see the shiny area where the belt once went to almost the top of the sheaves. I bet you will almost double your top end speed when you get this corrected. If you look at your driven clutch attached to the T-20, I bet it is only going half down the clutch. Best of luck with it. RR
Last edited by Reconrokon; 08-26-2017 at 04:42 PM.
Question -Since you owned the machine, has it ever gotten above the 15 mph top speed? I wonder if it had a problem when you bought it. Some things that could be going wrong include resistance in either the driven or drive clutch. If there is rust build up on the sliding parts of the clutches could mechanically limit their travel (it either one is limited it will necessarily limit the other also).
Thank you for the replies and the video. I purchased this machine two months ago. The previous owner only owned it for a few years and was getting the same speeds as me. Apparently it sat outside for a number of years before he purchased it and he had to replace all bearings, chains, and two axles. Rust could definitely be a factor. I sprayed WD-40 into the clutch last night with not much noticeable results. I will correct the belt deflection this weekend and will post back the progress if any. Thanks!
It's hard to tell but in that video it looks to me like your primary is working but your secondary appears to be stuck shut. The belt is able to climb half way up the primary sheaves because you have a good 2" of deflection, maybe more. I would soak the back of the secondary with a creeping lube, make sure it can travel the full ramp.
I adjusted the belt deflection to slightly over 1" and also was able to manually push the governor linkage to get to up to 4,000 RPMs. Unfortunately I am still geting the same clutch travel. I have attached a video of my secondary while giving it full throttle. Any ideas on what I should try next?
Wow. If that really is 4000 RPM,your secondary clutch is not working by a wide margin. Are you sure that it is the right belt and that it is not worn too narrow? Is it worth getting a new belt and keeping the old one for a spare?
What are you using to get RPM? That doesn't sound like 4k. Looks and sounds more like 2k. If you are using one of the digital tach/hour meter you might have it on the wrong setting.
Unfortunately the sound on the video is not accurate to what it sounds like in person. The video sounds like it's at idle. At 4k rpms it is screaming in person. I currently have the Tac set at the setting where the spark plug fires 1 time per revolution.
I recently changed the belt to a Carlisle 1042M3 (44-1/8" X 1- 3/16"). I am getting the same results with this belt and the old stretched belt.
Not sure what my next steps should be. Should I try to pry open the primary and secondary? If so, what is the best method to do this?
Regardless of the belt length or condition, your drive clutch should cycle through its full motion. Don't pry on the primary clutch. I would start with the secondary clutch. As you say, pry it open but its not easy. As you pry give it some twist to help the ramps climb each other. Don't pry so hard that you bend your sheaves, though.
Quite frankly, if it were mine and the secondary clutch has clearance to come off without too much trouble, I would pull the clutch and disassemble it to make sure everything is nice and clean and working as it should.
A word of caution on your primary clutch.....if you have the belt removed and rev the engine up, you may see the clutch "close" as it should. BUT it will stick in the closed position and it's hard to unstick it. One member recently did this and broke the clutch trying to get back to its normal position.
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