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Old 12-18-2018, 04:59 PM
Cmdrca Cmdrca is offline
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Default Torque Converter Belt issues

Hi fellas-trying to get my kart good for my kids for Christmas. I have a predator 212cc with a Chinese knock off Comet Torque Converter. Solid axle on an old Trailmaster buggy frame.
I got good tension on the chain and the Kart rode ok. But then belt started smoking about 15 Minutes later. And the belt folded over itself. Iíll upload a picture. Is there too much drag on the axle? The belt must have gotten too hot for some reason-but why? I appreciate any input.
It looks like the driven pulley is a little out of line but I couldnít figure out how to move it more.
Iím using the belt that came with the unit-Iíve read on here that a comet belt is the way to go but I want to be sure I donít have something wrong first.
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Old 12-18-2018, 06:30 PM
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KartFab KartFab is offline
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gear ratio problems. gear the kart for 25-28 mph at 3600 rpm.

Im no expert but I bet your kart may have had a gy6 engine on it with some 30-40 something tooth axle sprocket, and you welded up a motor mount on it and its geared for like 60 mph, so from zero to 30 mph you are spinning belts

think about it this way, if you ever drive a manual stick shift car/truck, would you try to start moving in 5th gear? That is esentially what you are doing here.

gear ratio options include (for 18" tires)

8t type c, 9t type c or 10t type c (the one that you probalby have on it right now)

any of those would work fine with either a 60t or 72t axle sprocket running 420 chain. Not sure about tire size or frame clearance but 60t is a really popular one.

If the kart is very light weight with a single rider, you may be able to get away with a top speed at 3600 rpm of 35 mph. a small two seater is best geared for 28 mph at 3600 rpm.

these are just guidelines from someone who has tried a few gear ratios and seen what manufacturers have done with their go karts over the years. You are more than welcome to experiment yourself, but trust me when i say gear for 28 mph at 3600 rpm on a small two seater go kart with a predator 212 and torque converter. It will work out perfectly!

That is until you start getting performance parts for it and exceed the 8 hp rating for the 30 series.
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Old 12-19-2018, 06:42 AM
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^ What he said. That little old sprocket down there on the axle is your problem. I'm sure there's some pretty big wheel/tires on the ends of the axle too. Axle sprocket should be LARGE.
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Old 12-19-2018, 08:09 AM
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If I recall, those trailmaster frames don't leave a whole lot of room to put a big sprocket on the axle dot-dot. You may have to go with a jackshaft.
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Old 12-19-2018, 04:23 PM
Cmdrca Cmdrca is offline
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Thanks fellas. I’ve been trying to look for a larger sprocket but the inside diameter is 1.5” to bolt to the welded hub on the axle. Most sprockets I’ve found have a 2” or larger ID. Is there a place I can find a 1.5” sprocket with more teeth? I think this one is a 48 tooth.
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Old 04-27-2019, 03:23 PM
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I have a 30 series TC with 7" driven pulley and run the 203591 belts. But here recently the belts are catching when pulling pull cord. The drive pulley is not engaged and belt has a little slack like it's suppose to. Help please, it's very aggravating.
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Old 04-27-2019, 04:25 PM
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Again, no hijacking threads please.
Please start your own thread.
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