Belt pinched

Yerfman56

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I bought a bullit lines 30 cvt off Amazon and after driving it around for about an hour the belt got pinched in the driven pulley. I was slowing down from going full speed. It was so violent my whole axle froze, Bent my engine mount and snapped all four of my bolts. What would cause this to happen and is there anything I can do about it? Thanks
 

madprofessor

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Having the exact same problem except the kart's way overbuilt, nothing broke or ever would. Locked up at speed twice so far, after letting off the gas. Kart's about 700 lbs. with me sitting in it, really violent lockup of my straight axle, quite a set of skid marks on the pavement.
Mine's a cheap ebay Chinese CVT, and everybody says trash the belt and get a genuine Comet belt, and I agree. The other thing is to tighten up the driven's spring to keep the sheaves together better. Attaching a YouTube link of the best example I've found on how to do it.
Changing The Spring Setting On a 30 Series Torque Converter - How To Get More Torque - YouTube
EDIT: Here's a link that will explain all about CVT's and their belts, has alignment diagrams, and a whole page at the bottom you need to read.........
Comet Drive Belts | Comet Torque Converter Belts | Go Kart Belts (gokartsupply.com)
 
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madprofessor

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The Gokart Supply link above will tell you how to measure for the correct Comet belt. Then don't maybe, just do. The correct belt will be under the first belts heading, for 3/4" wide asymmetric belts that fit the 30 series TC's. Just follow the instructions on measuring.
 

madprofessor

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Don't forget that your 30 series CVT uses an asymmetric belt, the only series that does, all the others use symmetrical belts. The "flat" side (actually 2.5 degrees) of the belt is toward the engine, and the "V" side (18 degrees) of the belt is away from the engine.
This isn't explained in the Gokart Supply web page above, obviously just an oversight. You can simply look down into the belt groove of either pulley and clearly see that one side looks flat and the other side angled. Belt lays in there to match.
 

Snaker

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During routine maintenance I like to put the driven back together without the spring. It allows me to slide the movable sheave around, wiggle, check for binding, slop, etc. Same goes for the drive. First thing to do when troubleshooting as well. Not a bad thing to do when brand new to get a bench mark on how it should be.
 
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