126cc Subaru Robin no acceleration

[cadams23]

Hi all, first post here.

I have what I believe is a Manco Hyper Fox. 126cc Robin Subaru engine.

When I first rode it it seemed like clutch was slipping and it was smoking.

I ordered a clutch on Amazon. 3/4” 10t. FYI I didn’t not disassemble the new clutch and did not lube, grease or oil. Maybe this is the issue.

With new clutch on wheels spin when given gas and back is lifted off the ground. When I try to ride it there is no torque and won’t go. If someone pushed me to get it going it will go but if i come to a stop I cannot get it to accelerate again unless pushed. View attachment IMG_1842.jpegView attachment IMG_1841.jpeg

 

[Denny]

Probably because it’s supposed to have a CVT on it and not a clutch. By the way that new clutch you just bought you might as well throw it away because with those big tires I guarantee you burned it up.

 

[cadams23]

Probably because it’s supposed to have a CVT on it and not a clutch. By the way that new clutch you just bought you might as well throw it away because with those big tires I guarantee you burned it up.

Thanks for the info. I just replaced what was on there with something similar.

Can you elaborate a little on the CVT or possible send me a link to something that would work with this setup?

 

[JimD]

Denny is saying a clutch would only work if the rear sprocket on the axle had 60 teeth and the tires were no bigger than 12.5" in diameter. Anything bigger than that your gear ratio would not turn the rear axle unless you lived on the top of the hill and never had to go back up to the top. The gear ratio and the tire size is much better handled with a t/c once the tire size gets bigger than 12.5" in diameter. The person put a clutch on the kart to unload on someone else rather than put the t/c back on it. Pictures of the kart always help out when the guys on the site give advice.

 

[Denny]

Jim is right, he should know, he owns Max-Torque clutches. Post pictures right to the site instead of links. While you gave us pictures you did not give us the views we need to help you further. We need pictures from the rear and the sides.

 

[cadams23]

Thanks guys. Here’s some pics of the setup.

 

[panchothedog]

No chance at all without torque converter. Everything JimD and Denny told you is absolutely correct. One thing I would like to add. With the torque converter properly installed the kart will take off from a dead stop and have a bit of acceleration. With only a 126cc engine, it will be very low powered. How old is the principle driver? If it's for a small child on somewhat level ground, it could be perfect. If it is for a full sized teenager or an adult you might find it a little disappointing. FWIW. A torque converter purchased for your current engine would be compatible with a larger engine should you decide to do that in the future.

 

[panchothedog]

If you don't know anything about torque converters, what you need is a 30 series. Weather you use the jack shaft setup that's on your kart now, or go to a larger axle sprocket ( going directly from the converter to the axle ) you need to end up with a 6 to 1 gear ratio. BTW, nice looking kart. SHARP.

 

[Denny]

Pancho nailed it!

 

[cadams23]

I really appreciate all the info. My dad got this kart at an auction and put some cosmetic money into it and the tires.

I think what I’m going to do is get a predator 212 and a torque converter. My son is not old enough to ride it yet, so I will be the one driving.

will a 212 and a cvt carry me and the kart? I’m about 200lbs.

 

[JimD]

With those tires you definitely need the torque converter. The good news is you didn't pay much for the china clutch on it now but even a Max-Torque would not have held up. The Subaru engine is a damn good engine, right up there with a Honda. Once you put the series 30 t/c on it will handle your weight easily. The nice thing about a t/c is you can drive it slow and not hurt it. Diving a clutch kart slow like in a parade, it will not last a block. There is only one speed for a clutch--pedal to the metal, lock it up as quick as you can so it can start to cool down. Stop and go driving is death to a clutch kart.

 

[cadams23]

Ok cool.

Let’s say I get a 30 series tc. I have a 40 chain and will use the 10t sprocket on the tc. What type of axel sprocket should I run?

 

[JimD]

Look on the chain links and tell me if it is #41, #420, #40 or what you don't want is #428. All four of these chains are 1/2" pitch. Tell me how many teeth are on the other sprockets the 10 tooth on the T/C is going to???, then the next chain on the same shaft that the T/C went to has how many teeth? and last how many teeth on the axle sprocket.

Measure the thickness of the sprockets -- I think you will find they are .227. I don't think any of them are .284 which is the thickness of a #40 sprocket. I don't know anyone that use a #40 accept snowmobile manufacturers.

 

[cadams23]

Looks like chain says 402. Sprocket on axel has 40t I believe.

How would I adjust or remove this sprocket if needed? I don’t see any set screws or anything.

 

[Denny]

You would need an axle sprocket with 60 teeth for a 10 tooth driver or 60:10 or 6:1.
There has to be a set screw somewhere. That sprocket needs to go by, by.

 

[JimD]

I looked at your pictures again and saw the black chain just after the master link has #420 which is prestretched #41 chain which was what most kart manufacturers used. Counting the teeth by YOU isn't that hard. Clean off each of the sprockets with some gas so you can mark a tooth with a magic marker. Put the bumper on a crate so you can free spin the rear wheels and COUNT the teeth accurately. A good guess isn't worth much, we want to know the exact number of teeth on each of the three sprockets on the kart. We don't care about the clutch since that is coming off. Also want the exact height of the rear wheel from the ground dead center through the axle to the top of the tire. This helps in giving you the speed of the kart and it only is accurate when we know the teeth count of each of the sprockets. Most likely those are the original Manco sprockets and they worked before and they will work again once you put the series 30 T/C back on the kart but since the people on this site like to be positive when they give you a recommendation. We need the teeth count and tire diameter.

Hold off on taking any sprockets off the kart until we figure out the true kart speed with the t/c on it.

 

[cadams23]

Sprocket on axel is 40t. Clutch and jack shaft have been removed. I don’t need the jack shaft with the tc correct?

Tires are 18x9.5-8

 

[Hellion]

Submitting for forum approval -- is this PDF the kart in question? A quick duckduckGo turned up the kart model number... Manco 3005 B-09
(or it could be the sister kart 3006 B-01). The plot thickens as it appears to be a jackshaft setup from the factory...

https://gokartsrus.com/media/wysiwyg/PDF_GO-KART/3005B-09_3006B-01.pdf

10T Clutch
12T/23T Sprocket (the other number is the other kart specs)
40T Sprocket


*Always helps to measure the actual rear tire diameter and at the proper inflation as advertised tire sizes can be off by inches.

 

[panchothedog]

Sprocket on axel is 40t. Clutch and jack shaft have been removed. I don’t need the jack shaft with the tc correct?

Tires are 18x9.5-8

Not correct. The torque converter sprocket will be a 10 tooth. For a 6 to 1 gear ratio which is what you must have, either change the axle sprocket to a 60, or let the torque converter transfer power to the jack shaft setup as is. Either way will work. But it has to be 6 to 1 gear ratio. Shouldn't be that darn hard to figure out. If you try to run the torque converter direct to your 40 tooth sprocket, you will be at a 4 to 1 gear ratio and do nothing but burn up belts. How bad at mathematics are you? This is simple stuff.

 

[cadams23]

Not correct. The torque converter sprocket will be a 10 tooth. For a 6 to 1 gear ratio which is what you must have, either change the axle sprocket to a 60, or let the torque converter transfer power to the jack shaft setup as is. Either way will work. But it has to be 6 to 1 gear ratio. Shouldn't be that darn hard to figure out. If you try to run the torque converter direct to your 40 tooth sprocket, you will be at a 4 to 1 gear ratio and do nothing but burn up belts. How bad at mathematics are you? This is simple stuff.

I have this kart for about 3 days and have learned quite a bit. I found a gear ratio calculator and learned how it calculates.

I thought this forum was for helping ppl out, and don’t think I’ve asked anything too stupid for being into this for 3 days.

Not sure why you have to post a dick *** comment like that. Did Pancho die or something?