Belt keeps burning

[Nate239]

i currently have a 30 series Tc and Ive tried to get the belt as straight as possible but after 30 mins or so of riding belt started melting on the sides and then broke. Could it be because its too close to the predator engine and the heat is making it melt? or is it the weight its pushing on the go kart?

 

[ezcome-ezgo]

Welcome Nathan. Do you have any picture of it before the melt-down? If not maybe some pictures of the current state would help. Need to see the sprockets, wheels etc. Could be a gear ratio issue.

 

[redflash]

could also been cheap crappy Chinese belt......no matter the cost ALWAYS .....buy a COMET belt.......lesson we have all learned !

Da redflash

 

[JimD]

Need a lot more info and pictures always help. Count the number of teeth on the small sprocket next to the driven unit, then give a a teeth count on the axle sprocket. Close up picture of the driven unit showing the wear ramps. Picture of the cover guard to see how many holes are in it for maximum cooling. Like to see the sheaves to see how they look on both driver (engine and driven (on jackshaft). Measure tire size from the ground to the top of the tire only concerned with tires on the axle. Since you are in Florida is it riding on the sand a lot or are you riding it on the roads? Is the cover guard on the unit when you ride it? Sand tends to screw up a lot of things quick keep it as sand free is going to be a must because of the moving parts in a t/c. Something else to consider.

 

[Nate239]

Need a lot more info and pictures always help. Count the number of teeth on the small sprocket next to the driven unit, then give a a teeth count on the axle sprocket. Close up picture of the driven unit showing the wear ramps. Picture of the cover guard to see how many holes are in it for maximum cooling. Like to see the sheaves to see how they look on both driver (engine and driven (on jackshaft). Measure tire size from the ground to the top of the tire only concerned with tires on the axle. Since you are in Florida is it riding on the sand a lot or are you riding it on the roads? Is the cover guard on the unit when you ride it? Sand tends to screw up a lot of things quick keep it as sand free is going to be a must because of the moving parts in a t/c. Something else to consider.

could also been cheap crappy Chinese belt......no matter the cost ALWAYS .....buy a COMET belt.......lesson we have all learned !

Da redflash

Welcome Nathan. Do you have any picture of it before the melt-down? If not maybe some pictures of the current state would help. Need to see the sprockets, wheels etc. Could be a gear ratio issue.

The small sprocket has 11 teeth and the big sprocket has 72 teeth don't really know if that's alot it had came with the go kart when i bought it but as you see in the pictures the sides have burnt rubber on them. Also i don't keep the cover guard on it.

 

[JimD]

That is a real weird set up. Now I understand when you said you try to get the belt straight. In most cases the 11 tooth sprocket would be behind the driven unit not in front of it so I can see why the belt is not going on straight. Is it possible to move the large sprocket inward if you were to move the small sprocket to the correct position. I think if you count the teeth on the small sprocket again you are going to come up with 12. The chain sure could use a little 30 weight oil on it so it will turn a lot smoother. Some more pictures showing the back of the t/c mounting plate for the clearance as well as a picture down low so we can see where the axle sprocket is sitting and the chances of moving it inward.

 

[BrownStainRacing]

The small sprocket has 11 teeth and the big sprocket has 72 teeth don't really know if that's alot it had came with the go kart when i bought it but as you see in the pictures the sides have burnt rubber on them. Also i don't keep the cover guard on it.
View attachment 138261

@jim Would definitely know more then i would. But to me it looks like the driver need to be shimmed out some.

i wonder if the jackshaft sprocket being on the outside is causing the jackshaft to bend, allowing the driven to cock over??? Or the t/c plate is flexing more??

maybe a longer jackshaft with a pillow block bearing supported on the end???

Whats the tire height???

 

[BaconBitRacing]

We sure that driven isn’t off a 20 series? Forgive my ignorance, it doesn’t look like a 30 to me. It’s pretty easy to put the belt on backwards, make sure it is on the correct direction, 30 series belts only work one way. I echo the Comet belt comment. The TC gear looks to me like it was put the wrong side, never seen one on that side. @JimD is the man to listen to, he works for a TC and clutch company (Max-torque?).

 

[ezcome-ezgo]

 

[BrownStainRacing]

View attachment 138265

The driven cutting into the plate is not helping things.

Good eye!!!

 

[JimD]

You should try and avoid moving the driver unit for adjustment. It only has so much key in the 4 spline which is HARDEN and can tear up a soft keyway of the crankshaft. The ramp is on the correct side of the wear plug to be an outboard mount which is the normal for a series 30. Would like to see several more pictures the show the mounting plate better next to the engine and hopefully get a look see at the axle with the sprocket on it. This we would like to see if it could be moved towards the engine so if the sprocket on the jackshaft was on the other side of the driven, can we get the chain down to it which might solve his problem of the belt having such a short life. Even a crap belt from china should last longer than 10 minutes.

 

[Nate239]

That is a real weird set up. Now I understand when you said you try to get the belt straight. In most cases the 11 tooth sprocket would be behind the driven unit not in front of it so I can see why the belt is not going on straight. Is it possible to move the large sprocket inward if you were to move the small sprocket to the correct position. I think if you count the teeth on the small sprocket again you are going to come up with 12. The chain sure could use a little 30 weight oil on it so it will turn a lot smoother. Some more pictures showing the back of the t/c mounting plate for the clearance as well as a picture down low so we can see where the axle sprocket is sitting and the chances of moving it inward.

The sprocket is welded to the axle so it would be kinda hard to move it to the other side

 

[BrownStainRacing]

The sprocket is welded to the axle so it would be kinda hard to move it to the other side
View attachment 138263View attachment 138266

Definitely need more gear, after you get the t/c squared up.

I recommend a 7" driven for any tire over 16" on a Kart or buggy.

 

[BrownStainRacing]

I know this is not a smart question but can you please explain what is 7” driven ?

The big pulley in back, next to the little sprocket is called the "driven". The smaller pulley on crankshaft is called the "driver".

The 7" will start out(low side) as a lower gear then the 6". 7" will also have a lower gear when the t/c gets into the high side.

@JimD will be know more about the ratios then me.

But I maybe close or way off here.

The 7" on the low side will be around 3.00:1- 3.15:1.

The 6" on the low side will be around 2.4:1- 2.7:1.

@JimD , PLEASE correct me if I'm wrong on the ratios. I'm sure others have also wondered what they truly are.

 

[Denny]

If it was my kart I would start with a new axle and sprocket. I would also switch to a 40 series with a plate CVT with a Genuine Comet belt of the proper size. I would also switch to #40 series chain. But that is me. Jim I have seen the chineseum belts burn off in 10 minutes, when replaced with Comet belt the Comet lasted 3 years ridden daily for about 4 hours!

 

[Master Hack]

That just looks wrong to me. The driven has worn a groove in the mounting plate? Am l seeing that right?
wow!

it has been brought to my attention that the current batch of chinese belts have been produced with uncured yak grease!
Being uncured has lowered the flash point if the belts from 211F to a dismal 158F. That low flash point causes the rice fiber in the belt to burn uncontrollably once that grease catches fire.
Be advised to remove all chinese belts right away.

on a side note the discarded belts make great camp fire starters!

 

[JimD]

And I thought all the writers were on strike in CA. We certainly have some great comedians in this group, Hollywood watch out!!!!

Brown Stain - you are rear good on your ratios.

WOW, that welded sprocket to the axle certain limits any suggestions on how to correct. Could it have been a split sprocket on the axle and Mr. Welder when and welded the two pieces together?? The 22" tire certainly is a challenge for a 6" driven. This is one of those projects you are glad it is someone else's money pit. How much money is he willing to dump into this project. The series 40 will not help on a 3/4" crankshaft. He has a band brake on the axle and most likely looking at some of the welds on this frame he will not be able to salvage that because he will not be able to get it off the axle for the replacement, lease of his worries.

Glad he is in Florida because it will not show up at my door asking for help because this is a huge project and it is going to cost him plenty. Anything can be fixed but you have to ask yourself do I want to put that much money into it. There are better karts out there that will not be such a money pit. Turning a tire that large would need a larger horse power engine for some much needed torque. When he is done he will be a super mechanic.

Denny is correct about getting rid of the axle and everything attached to it and start fresh. If you want to use the engine then drop down to a 14" to16" tire, kart will still look nice and you can save the other tires for your next build. This way you can use the same engine you have and correct the torque converter and rebuild it the way it was designed. No matter what it is going to be a long project and you will put a good deal of time and money into it but when you are done it is the satisfaction of looking at it and saying I BUILT THAT KART.

 

[Nate239]

And I thought all the writers were on strike in CA. We certainly have some great comedians in this group, Hollywood watch out!!!!

Brown Stain - you are rear good on your ratios.

WOW, that welded sprocket to the axle certain limits any suggestions on how to correct. Could it have been a split sprocket on the axle and Mr. Welder when and welded the two pieces together?? The 22" tire certainly is a challenge for a 6" driven. This is one of those projects you are glad it is someone else's money pit. How much money is he willing to dump into this project. The series 40 will not help on a 3/4" crankshaft. He has a band brake on the axle and most likely looking at some of the welds on this frame he will not be able to salvage that because he will not be able to get it off the axle for the replacement, lease of his worries.

Glad he is in Florida because it will not show up at my door asking for help because this is a huge project and it is going to cost him plenty. Anything can be fixed but you have to ask yourself do I want to put that much money into it. There are better karts out there that will not be such a money pit. Turning a tire that large would need a larger horse power engine for some much needed torque. When he is done he will be a super mechanic.

Denny is correct about getting rid of the axle and everything attached to it and start fresh. If you want to use the engine then drop down to a 14" to16" tire, kart will still look nice and you can save the other tires for your next build. This way you can use the same engine you have and correct the torque converter and rebuild it the way it was designed. No matter what it is going to be a long project and you will put a good deal of time and money into it but when you are done it is the satisfaction of looking at it and saying I BUILT THAT KART.

I am willing to put any money towards this go kart but i would also like to keep the big tires so that must mean i would need a bigger engine (looking into getting the 440cc duromax). Also looking to put new gen steering and a whole new axle debating if i should keep the drum brakes or go with new gen brakes ,also when ordering parts for the axle how much teeth should be on the sprocket to be able to handle the offroad. If i get the T/C fixed would it keep burning belts until i upgrade if i keep riding on it?

 

[Denny]

If you go 440 you will have to upgrade to a 40 series CVT and Comet belt. A 30 series will not fit and will be too light. The drum brake should be adequate. See if you can get the hubs off your axle, you may be able to reuse them. Step up to 40 series sprockets and chain. 10 tooth small, 60 tooth axle for a 6:1 ratio. Then you’ll be golden for the 22’’ tires! Get a 1” full keyed axle.

 

[JimD]

You must have a good size wallet. With that engine you would move up to the series 40 T/C . You would get rid of the band brake and switch to a mechanical disk brake. You will have to build your own jackshaft arrangement with the series 40 but that is no big deal but use a 3/4" jackshaft (avoid the 5/8" with tires as big as you have you would bend the jackshaft when you brake hard). Go with a 10 tooth #40 sprocket on your 3/4" jackshaft going down to 66 tooth axle sprocket. You can get the sprockets and the carrier from Azusa in CA. They make a lot of the things themselves and they did supply many of the backyard fun kart manufacturers. BMI is another good source, they bought up much of the stock of the fun kart manufactures when they closed their doors in 2005. Lot of good companies out there so ask them what they would recommend. I sure as hell don't know it all, if I did I would have run for President.