help with CVT - new to this and trying to figure it out

[jpcjguy]

Hi all,

So I am new to this and I have a 2014 Kandi Spyder that I tore apart to repaint. The belt broke on the previous owner.

I took the drive pulley apart. The rollers have a flat spot on them. Pretty uniform. One of them the "outer shell" of the roller is worn down to the inner metal. Should I replace them?
Here are pics of everything. What should I do next? I do have a can of Comet GP-730A dry lubricant.

[jpcjguy]

Oh - and I counted the teeth on the gears. 31 and 17 - so what is that 1.82 ratio? good/bad?

[jmansracerocket]

Originally Posted by jpcjguy

Hi all,

So I am new to this and I have a 2014 Kandi Spyder that I tore apart to repaint. The belt broke on the previous owner.

I took the drive pulley apart. The rollers have a flat spot on them. Pretty uniform. One of them the "outer shell" of the roller is worn down to the inner metal. Should I replace them?
Here are pics of everything. What should I do next? I do have a can of Comet GP-730A dry lubricant.

jpc, I'm thinking of the buggy you have, I'm pretty sure those are decent size buggies, and have decent weight to them. I know there 2 seaters also. So depending if your looking for a little more take off vs. top end I would recommend 10 gram rollers, and 10 gram sliders. Also the variator it self looks worn, either you can clean it out, replace with a new stock one, or they have different brand variators. So far I like the stock variator. Of course get your self a new belt. All and all you shouldn't have to spend more then $50. While you are in the cvt area, I would look over your clutch system, I bet its warn out.

[jpcjguy]

jmansracerocket - thanks for the reply!

It is a big buggy. Here is a pic of what it looks like:


So why the 10g weights? roller or slider? I hear opinions all over the board. I am 6'5 240lbs so I need a good balance of torque and speed. Top end is not my priority - getting over hills is.

So a variator assembly like this:
https://www.amazon.com/GOOFIT-Comple.../dp/B00T47X44O

[jmansracerocket]

yup that's the one I had in my head, they are heavy machines, and you are a big guy. I would recommend 10 gram slider or rollers then. The sliders is suppose to move easier in the variator, and the slider from what ive seen, seems to last a little longer, but its a cheap item. I thinks its preference. Don't know how handy you are, but you will really benefit from a big port, big valve head, with a cam. Those stock rollers that come with that link you posted from amazon, is 14 gram rollers, which scooters usually use. I see amazon has the belt for $9 which is super cheap.

[jpcjguy]

Here is a picture of the clutch - a bit rusty. It does spin open smoothly. Can I clean it up and use it? Sand and paint?

[jmansracerocket]

you can degrease it, and clean it with a blow gun, you can try a yellow tq spring, which will also help that buggy. The clutch itself looks like it still has some life left on it.

[fan4chevy]

In my opinion I would toss it all in the trash and get all the new performance goodies. It is so cheap for this engine to replace it all, especially compared to name brand.

I bet for about $100 you can have a whole new performance cvt and much better performance. Besides, the bell could be warped.

[jpcjguy]

Definitely need new springs in the clutch - pulled on one and the spring bent and is not tight anymore. How about something like this?

https://www.amazon.com/Glixal-ATKS-0...s=clutch+150cc

[jmansracerocket]

Originally Posted by jpcjguy

Definitely need new springs in the clutch - pulled on one and the spring bent and is not tight anymore. How about something like this?

https://www.amazon.com/Glixal-ATKS-0...s=clutch+150cc

yup that's the tq spring

[jmansracerocket]

Originally Posted by fan4chevy

In my opinion I would toss it all in the trash and get all the new performance goodies. It is so cheap for this engine to replace it all, especially compared to name brand.

I bet for about $100 you can have a whole new performance cvt and much better performance. Besides, the bell could be warped.

I agree, that's why I recommended putting a new variator in. The clutch me personally I would just change the whole thing. I have a prodigy clutch here that I cant wait to try out this summer.

[jpcjguy]

Also this is a 1P57QMJ motor - good or bad? Anything to watch out for when ordering parts?

[jmansracerocket]

Originally Posted by jpcjguy

Also this is a 1P57QMJ motor - good or bad? Anything to watch out for when ordering parts?

as far as I can remember some of them are casted/ manufactured in different places, I know there is a gy6 engine out there that has 2 bolts holding the valve cover on, that people say stay away from. you want the gy6 with 4 bolts holding down the valve cover and your good to go.

[jpcjguy]

Originally Posted by fan4chevy

In my opinion I would toss it all in the trash and get all the new performance goodies. It is so cheap for this engine to replace it all, especially compared to name brand.

I bet for about $100 you can have a whole new performance cvt and much better performance. Besides, the bell could be warped.

So I can get a yellow spring kit for $10 or a clutch kit for around $30 - but I would still need to get the yellow spring kit. Unless someone sells a clutch kit with yellow already in it?

Not trying to be too cheap, but I already got all new bearings and seals for front/rear wheels. At this point I want to get it together and confirm everything runs well....

[x-bird]

the Ps are also a bit of an oddball, internal reverse gy6, I had one i sold off to a new home, i do believe the crank is unique to it, but the head/jug are the normal 4-bolt valve cover spacing so the performance parts aren't an issue. like the old 2-bolt Syms that carter talons had. but that Sym engine didn't need much help performance wise either, was a real honey of a gy6.

[jpcjguy]

Originally Posted by fan4chevy

In my opinion I would toss it all in the trash and get all the new performance goodies. It is so cheap for this engine to replace it all, especially compared to name brand.

I bet for about $100 you can have a whole new performance cvt and much better performance. Besides, the bell could be warped.

So what do you recommend? Why did you choose 12g - others recommend 10g. Trying to figure all this out...

[jmansracerocket]

U can go with a after market clutch if u want that has different clutch springs, but alot of people like the stock one with a choice of tq spring, and pillow cltuch springs. The dr, pulley clutch is $300 bucks, ive never used one, and u would be better off with a head and cam like i said. The prodigy clutch i purchased is suppose to be a good quality whish is $120. Its ur choice. There also japenese ba jing clutches, and some other knock offs, just google it.

[fan4chevy]

Jpcjguy,

I am not as experienced as others on this and maybe others can pipe in, but this is my view on it.

I actually chose 12g Sliders after much research. It is equal to 10g rollers. It seems for buggies, the most popular is either of these two combos. Some like sliders and some rollers.

The rollers are smoother, but the sliders are known for lifting the variator open a bit more due to the angle. However, you can feel it when it shifts more. I also added a Kevlar belt.

For the money, I think a good combo is a KOSO or NCY clutch with 1500 or 2000 rpm springs and 1500 main spring. I have the Ban jing clutch bell. On the variator I also like the Koso variator. NCY is a well known brand though.

Keep in mind though that stock springs are 1000rpm I believe, so I think some people mistake the 2000 as slippage but in reality it just takes until 2000 to launch. However, I feel it is a much more powerful start this way.

Another thing I added was a main contra spring bearing kit. It is a sleeve that the main spring sits on that has bearings so that the main spring can move freely and not bind. Much smoother.

When I added this combo, the power from stop was much more powerful compared to my other buggy all stock cvt.

[xlint89]

Welcome to the site.

Here's a good short video that teaches you exactly how a CVT works. It's covers it all in about 3 mins.

https://www.youtube.com/watch?v=uCEvBGT8twM


I too like the stock variator, didn't see much if any gains from aftermarket.

When it comes to variator weights, compromise is key.

lighter = more take off at top speed expense. Light weight takes longer to move due to centrifugal force, so engine RPM is higher when the buggy starts to move. More take off, or torque if you will. On the top speed side, there is less mass putting pressure on the variator to squeeze the sheaves together forcing the belt to the outside, so you will see less peak speed.

Heavier = sooner take off resulting in lower engine RPM as the buggie starts to move. Less torque if you will. However, the added pressure due to more weight applied to the sheave should force the belt to the outer most part of the sheave resulting in more top speed.

Notice in your pic how the outer most part of your variator is clean? That shows us your belt never really made it to that point. You will achieve maximum speed when you can get your belt all the way to the outer edge. If you're not after top speed, that means nothing.

So ideal variator weight is a balance of bottom end take off, and top speed. All easily adjusted, and ideally tailored to what you're looking for.

I personally like the sliders over rollers. They are slower to engage like a light weight roller, but with more weight for top speed pressure. Not to mention they do last longer. Rollers will flat side as you see in your pics. When that happens, they lose their benefit of fast reacting.

Now rollers are cheaper, so some will buy rollers to find the ideal weight for them. Then they can buy a slider equal to that weight if they decide to go that route. As Opposed to many different slider weights to find the ideal one.

I BELIEVE when choosing sliders you buy them 2 grams heavier than the rollers due to the delay in actuation. Hopefully someone will correct me on this if I'm wrong.

[xlint89]

Again, I have never used an aftermarket clutch. I do find the stock clutch to work just fine for me. The key to them is keeping any glazing down.

As the bell "slips" the bell will "blue" from heat and cause a polished slick surface on the bell and clutch linings.

That slick surface needs to be roughed up for proper perfromance.

It's quite acceptable to scuff the bell contact area with sand paper to remove any glazing. Also the same thing can be done with the clutch lining.

Changing the clutch shoe springs (little ones) will change the RPM that the clutch engages. The higher RPM the clutch engages, the more take off you will have. But it will be more of a "hard" take off, not really a smooth and easy take off.

Once again, stock works for me and compromise is key to what works best for YOU. Everyone will offer their opinion, but that's based on their buggy, weight, and terain that works best for them.

You being a bigger guy with a heavy buggy (going by what others have said, I have no idea what yours weighs) you might like the hard accel. But if you have kids or your wife, it may launch them too fast if they want to just tool around the yard.

The contra spring, or the big one, will affect the shift rate of the driven pulley. A heavier or higher RPM spring weight will slow down the shifting speed of the driven pulley resulting in holding "low gear" longer. More torque applied to the rear wheels because the belt hasn't started moving the gearing yet. It will also start down-shifting the buggie faster because of the tension is stronger to force the sheaves back together. This results in having good low end power coming out of a turn.

You may like a stronger spring (most prefer the yellow that I believe is 1500 RPM more than stock) for your application if you have hills. The buggy will hold more torque longer for your hill climbing.


It's really easy to get caught up in buying all kinds of parts for these buggies, but you really don't need too as long as you set up your CVT properly.

For me the stock variator, clutch, contra spring, and clutch springs work well. But I don't have any hills and I do mostly flat concrete riding. I do have an aftermarket driven pulley though. Which I found to have a little better accel even though they advertised more top speed. (no speed gain, but bottom end improved, so that is a plus in my book too)


The key for CVT's is heat. Keeping them as cool as possible is the cat's meow. Heat is what destroys belts. Clutch slipping creates heat and destroys clutches and bells.

I've found modifying the CVT's air intake for maximum air flow works well.

Mine came with a small bottle neck snorkle that let in small amounts of air. If it got plugged up with dirt or grass that just amplified the problem. I removed the snorkle and installed a scotch brite pad as a filter over the intake. That opened up the intake about 100% right there.

I then cleaned up all the casting slag in the outlet openings to allow the most air OUT as possible.

Those are 2 FREE modifications you can do the make your CVT more reliable and last longer.

[jmansracerocket]

Great posts xlint and fan4chevy.

[jpcjguy]

Thanks for all the info! I am going to start with the yellow springs and some 10g rollers and see how it acts. Then I can go from there (if I want).
As for cleaning up what I have - the pulleys for the belts - what do you all recommend?

[fan4chevy]

As far as the pulleys for the belts, unless you can get them spinning on a lathe or drill so you can clean them while spinning, I think you best bet is to get some scotch brite and rub them clean.

[xlint89]

Honestly, your driven/clutch look pretty beat to me. A lot of surface rust there.

The variator might be salvageable, but is that pitted in the middle of the sheaves?

If so, I'd replace them all. Any rough surfaces are going to chew up your belt pretty quickly.

[fan4chevy]

If it were me, I would bite the bullet and replace it all, you will be much happier and won't wear out good new parts due to bad old parts.

[SYCARMS]

12 gram rollers is what I would run. Do you have an internal reverse or external. You can tell buy if it has a neutral position on the shifter it is internal, no neutral = external. A performance variator is a larger diameter than stock and is a help with top end also depending on what you get the ramp design also helps by making it easier for the rollers to climb the ramp. Keep in mind if you for some reason decide to go with sliders instead of rollers, unless the variator is designed for sliders they will react differently than rollers due to less resistance. Example if you go with a 10 gr. roller, a 10gr. slider will act like a 8 gr. roller. The cheap parts for these are tempting but remember you get what you pay for for not all parts are created equal.

[jpcjguy]

It is an internal reverse. Thanks for the info!

[fan4chevy]

Sycarms,

Is it better to put in 14g Sliders then 12g sliders being that a 14g slider will be similar to 12gram rollers? I had thought that 12g sliders or 10g rollers were ideal for Buggies.

I have opened exhaust, redneck intake, Koso and NCY upgraded cvt and will be putting in a a12 cam. I am needing both hill climbing and long runs. Interested in getting your theory on this.

Charles

[SYCARMS]

Maybe in the sand or super steep hills but my experience has been anything lighter than a 12g roller or 14g slider the RPM's will be too high and a bunch of top end (speed) lost.My suggestion is that you do all your engine mods first. What you are doing when tuning the cvt the lighter the roller it is like downshifting your car into a lower gear. The difference is your car you can shift back up a gear the cvt you can't. The more power the engine has the heavier the roller you can run. In the beginning when my 150 had only an A12 cam jetted carb with a UNI and opened up exhaust the 12g rollers served me the best the 10g were too light.

[fan4chevy]

Sycarms,

This is another cvt question that I am trying to best understand over at a thread. Can you reply to it, I would love to hear your thoughts on it: http://www.buggymasters.com/forum/showthread.php?t=6086