Picked up a Couple of Karts - Help with Centrifugal Clutch Belt Drive

[nickb2325]

Picked these both up the other night. I started with the black one. Have the engine running now, but I have never seen a Centrifugal Clutch Belt Drive... I have had plenty of Centrifugal chain drives and belt torque convertors. Here is a picture:



Belt just slips under throttle. I tried moving the engine forward to tighten it, but it didn't really help.

Is there a way to adjust this anymore?
Is this a good system?
Should I switch for a chain?/ Should I go torque converter?

 

[Denny]

By the looks of that setup it may have had a CVT originally. My guess is someone along the line went cheap and came up with this system. It probably had a 20 series CVT system on it originally. Go to the GoKart Supply website to learn about them. The information you seek is under parts, clutches. Then come back here and tell us the brand, engine and model of kart and we can better help you out. Some good pictures of the kart would be helpful too.

 

[nickb2325]

By the looks of that setup it may have had a CVT originally. My guess is someone along the line went cheap and came up with this system. It probably had a 20 series CVT system on it originally. Go to the GoKart Supply website to learn about them. The information you seek is under parts, clutches. Then come back here and tell us the brand, engine and model of kart and we can better help you out. Some good pictures of the kart would be helpful too.

Its been repainted and modified. I have no clue what the black one is or was, the yellow one on the other hand I at least know is a Manco.. The engine on the black one was replaced with a 6.5hp greyhound a while ago.

I don't really know if they went cheap... the replacement Centrifugal Clutch Belt Drive cost as much as a whole 20/30 series kit. I would guess it is original to the kart but not this engine. Who knows though.

Looking for someone familiar with these types of drives... input if it is worth keeping or not, and how to adjust.

 

[Denny]

Looking closer at the karts they are MANCO Dingo 285. They would have come from the factory with 30 series CVT. Not the TAVII system though. They were built before that was designed. However if you remove the jackshaft assembly and centrifugal clutch you can bolt on a 30series TAVII CVT with the back plate. You can get a cheap kit from Amazon just Do Not Use The Chineseum Belt that comes with the kit. Buy the more expensive Genuine Comet Belt. They are 2x as expensive but last 10x longer.

 

[Denny]

No do not keep that system! It will not work and probably never has as is. My brother had the same kart back in 1988. About the same vintage as your kart. It came from the factory with a 5hp Briggs & Stratton flathead engine.
The yellow one is probably mid 90’s or later. Probably has a 6 hp Takashema (Tekumsa sp?).

 

[nickb2325]

Looking closer at the karts they are MANCO Dingo 285. They would have come from the factory with 30 series CVT. Not the TAVII system though. They were built before that was designed. However if you remove the jackshaft assembly and centrifugal clutch you can bolt on a 30series TAVII CVT with the back plate. You can get a cheap kit from Amazon just Do Not Use The Chineseum Belt that comes with the kit. Buy the more expensive Genuine Comet Belt. They are 2x as expensive but last 10x longer.

Okay thanks! I am more familiar with the 30 series. Good to know they both came with it. Yes, you are right, the yellow still has the Tecumseh on it and seems all original.

These and the 2x fl250 odysseys I picked up over the summer are going to be my winter projects.

 

[Denny]

I always as a kid wanted a odyssey! Lucky!
For my 19th birthday I bought me the 8 hp Dingo. That was the fun one!

 

[madprofessor]

Since common V-belts for cars and such are so cheap, I'd slap a new belt on there before throwing the parts away, and here's why............
See how the outer side of the belt is nestled down inside of both pulleys, as opposed to being even with the outer circumference of both of the pulleys? I'd bet dollars to donuts that it's because the belt's sides have been worn away to the point of changing a 4L belt to a 3L, just like I've seen literally hundreds of times in my career in HVACR. The reason you can't stop it from slipping under load is highly likely to be due to the belt resting on the bottom of at the very least the rear, if not both front and rear pulleys.
They're called V-belts because the V-shaped configuration is supposed to mate to the V-shaped groove of the sheaves. The V-belt MUST ride on the sides of the belt, and NOT on the bottom of the belt. Once the belt is on the bottom of a pulley, you can never tighten it enough not to slip under heavy load, at least not without destroying your bearings.
You still should get a CVT in the end, but with a belt you can play with the thing until you do.

 

[Denny]

Since common V-belts for cars and such are so cheap, I'd slap a new belt on there before throwing the parts away, and here's why............
See how the outer side of the belt is nestled down inside of both pulleys, as opposed to being even with the outer circumference of both of the pulleys? I'd bet dollars to donuts that it's because the belt's sides have been worn away to the point of changing a 4L belt to a 3L, just like I've seen literally hundreds of times in my career in HVACR. The reason you can't stop it from slipping under load is highly likely to be due to the belt resting on the bottom of at the very least the rear, if not both front and rear pulleys.
They're called V-belts because the V-shaped configuration is supposed to mate to the V-shaped groove of the sheaves. The V-belt MUST ride on the sides of the belt, and NOT on the bottom of the belt. Once the belt is on the bottom of a pulley, you can never tighten it enough not to slip under heavy load, at least not without destroying your bearings.
You still should get a CVT in the end, but with a belt you can play with the thing until you do.

Mad, look at the circumference of those pulleys that you are telling him to waste money on buying a new belt for. Even Ray Charles and Little Stevie Wonder can see it ain’t going to work!

 

[madprofessor]

Maybe retirement's being too kind to me, that I'd be willing to throw away $6-8 on an el cheapo Walmart or some such brand V-belt, but I'd have to do it to satisfy my curiosity. Curious if the new el cheapo would ride correctly in the V's, and curious to see it run the way it did back when it had a new belt on it.
Then I'd go ahead and toss the belt, and then put on either a clutch and sprocket and chain, or a CVT somehow.

 

[Denny]

Maybe retirement's being too kind to me, that I'd be willing to throw away $6-8 on an el cheapo Walmart or some such brand V-belt, but I'd have to do it to satisfy my curiosity. Curious if the new el cheapo would ride correctly in the V's, and curious to see it run the way it did back when it had a new belt on it.
Then I'd go ahead and toss the belt, and then put on either a clutch and sprocket and chain, or a CVT somehow.

Why? Those are MANCO Dingos. They came from the factory with a 30 series CVT. Long before the TAV II came out.

 

[madprofessor]

I surrender. Save your $8 of A-26 V-belt money and apply it to the CVT you need. Throw out all traces of the belt drive, including wiping all of the black pepper belt dust off of the motor so you won't be reminded of the belt drive.
A driver, a driven, and a chain will be over and done with making the kart right again.
If the jackshaft doesn't adjust for tension, don't forget about these half links when a whole link's too much...............
35 Standard Roller Chain Offset Link (10PCS) (jeremywellindustry.com)

 

[ezcome-ezgo]

The final gear ratio is probably undesirable, but I'm too lazy to count teeth and do math.

 

[JimD]

I agree with the Madprofessor -- go buy a BX belt the same circumference you have now on the "A" belt. It will work. The BX (the X) means it is cog underneath which will help it turn the tight radius of the 3.2" pulley size. The tires are not that big under 15" in diameter if they are larger than 15" I would say the T/C is the only way to go. To get the belt tighter you would put some washers under the engine on the motor mount plate.

 

[Denny]

Ok kids, the Dingos came with an 18” tall tire. The centrifugal clutch for a belt drive was never original to that kart. The belt ratio for those shieves is almost 1:1 by looking at it. Axle sprocket is 54 or 56 tooth with a 10 tooth on the jack shaft. Please explain to me how that tiny belt is going to hold that load. Must be nice to have money to throw away.

 

[JimD]

I commented that IF the tires were larger than 15" than you should go with a t/c . I can see that the pulley the clutch is going to is almost twice the size of the clutch pulley so it is closer to 6 inches than it is to 3". I am just saying for the cost of BX belt it is worth the try. If he lives in an area that is flat like Illinois or Indiana and the tire size is 15" it will work but if he is a hilly terrain it will be difficult. Since he didn't give us all the variables, all these suggestions are just that, none of them are etched in stone and he can go his own way and do what he wants.

 

[nickb2325]

I personally never thought that setup would work. In case I was very mistaken and had a lack of knowledge I wanted to know. The drive pulley was catching great, it was the rear pulley it was just slipping on. It was a 3" front pulley and 4" rear.

If it was chain drive maybe I would have stuck with it for a while. If the person driving the kart was under 50 lbs maybe the old setup would move but probably slip quite a bit. I'm 6'3" and 200lbs I just didn't seeing it work for me, maybe my kids.
I already bought the tav2, and some 420 chain and installed. On gps I hit about 32mph on my trail. I think this was the ideal situation, less than $80 total.

Video of my boys on the karts: https://photos.app.goo.gl/qV17fTQWiTacApMZ7

 

[Denny]

I don’t think you have the primary put together correctly. Might want to look over the instructions again. But am glad you got ‘em working though.

 

[madprofessor]

I don’t think you have the primary put together correctly.

That driver does look aberrant, the way the domed body sits kind of "countersunk" into the surrounding "dish".

go buy a BX belt the same circumference you have now on the "A" belt. It will work. The BX (the X) means it is cog underneath which will help it turn the tight radius of the 3.2" pulley size.

Absolutely correct on the X part, it signifies a cogged belt for use exclusively on getting around smaller diameter pulleys without cracking the rubber. Good call, JimD, not everyone understands what cogged belts are for.
I disagree on the B part though. A-belts (like on there now) and 4L-belts are 1/2" wide, albeit a couple of inches different from each other in length measurement, and that's what those pulleys look like. B-belts are 5/8" wide.

 

[nickb2325]

I don’t think you have the primary put together correctly. Might want to look over the instructions again. But am glad you got ‘em working though.

Good eyes. I was just test fitting for clearances and getting the sprockets aligned before I got the chain on in that pic. I realized I had it on wrong when I actually put it together and got it together right.