Tao 125 sprocket gearing

[Boosted19]

Hello I recently bought my kids brand new Tao 125 cheetahs. They have no low en power at all. They have to go full throttle to go up small hills and terrain on trails. Right now they have 13 tooth front and 41 rear. What would be a good ratio for them. Don’t want them doing wheelies or anything. But want decent low end and still keep decent top end when they get a bit older. Any advice appreciated. Thanks!

[david3921]

It's far easier and cheaper to change the front sprocket. Going down 1 tooth to a 12T is close to going up 3 teeth in the rear. I would try that first. If you still needed more torque, you should be able to go down to an 11T. If your chain is a 428 you should be able to find both front sprockets cheap.

BTW, make sure the throttle set screw is all the way out allowing the full throttle range.

[Boosted19]

Yes I think it’s a 420 chain by research I’ve been doing. How much is each tooth worth in top speed approx. and yes I have throttle limiter all way out. Thanks!

[GrandKidsMX]

If you have 13/41 gearing you likely have the "New Cheetah", not the older, "Cheetah".

I bought a New Cheetah last year for my 11yr old Granddaughter. Like you, I realized it was geared way too 'tall'. I changed the gearing to 12/45 and it is now much better. It's still doesn't have the torque to pull up a steep hill without some amount of 'runup' to the hill but it is now usable on hilly terrain.

Bye the way, a 45T rear sprocket still fits inside the chain-guard but just barely.

Also, you can't go smaller than a 12T on the front or the chain will rub on the swingarm pivot. Plus, you won't be able to fit the front sprocket keeper and 2-bolts on any sprocket smaller than a 12T. Even with a 12T you will have to grind the keeper & bolts a little to keep the chain from contacting the keeper & bolts.

Lastly, the chain is not a 420. The chain is a 428.


My Granddaughter climbing some hills on her New Cheetah!

[GrandKidsMX]

On another subject..., make sure you adjust the valve clearance shortly after the quad is broken-in. The valves were too tight on our New Cheetah.

I adjusted ours to .003" intake, and .005" exhaust.

I also replaced the non-adjustable stock carb with the same model, only in a fully adjustable version. After some jetting changes our New Cheetah starts easily, idles reliabley, and accelerates smoothly.

[Boosted19]

Awesome thanks for the info! Did you replace chain? Or have to take out links? Thanks!!!

[Boosted19]

Oh and where did you get the parts from? Have link? I believe it’s 17mm front correct and 68 rear?
These correct?
https://www.whygostock.com/428-taota...ting-diameter/

https://www.whygostock.com/taotao-42...igher-quality/
Looks like they don’t have a 45 rear actually. Would 12/42 be even worth it?

[GrandKidsMX]

Here are the parts I used. Front sprocket is 17mm and rear sprocket is 48mm center (not 52mm). However, you could use other sprockets if the bolt pattern matches, the I.D. could vary some so long as the I.D. is not undersized.

You'll have to buy some button allenhead bolts and then turn-down the diameter of the heads. You'll also have to grind down the sprocket keeper on the 'ears' where the bolts go through. If you don't do this the chain will ride-up on the bolt heads & sprocket keeper.

Front sprocket.
https://www.amazon.com/Wingsmoto-Spr.../dp/B010UQJWNO

Rear Sprocket.
https://www.bmikarts.com/428--45T-Re...EaAjnxEALw_wcB

https://www.vmcchineseparts.com/coll...mm-center-hole

And yes, I had to buy a longer chain and size the length to fit. I don't remember how many links I had to add..., but 4-links 'rings a bell'???

[Boosted19]

Thanks! That’s odd whygostock.com would send me a 68mm rear center hole sprocket and taoparts direct shows a 66mm. Weird

[GrandKidsMX]

Originally Posted by Boosted19

Thanks! That’s odd whygostock.com would send me a 68mm rear center hole sprocket

The link you showed has a 52MM center hole and the diameter of the bolt pattern is 68mm.

I can't comment on Whygostock parts as I didn't use them???

[Boosted19]

Ah maybe I read it wrong lol. Too many internet pages opened on phone haha

[GrandKidsMX]

Originally Posted by Boosted19

Ah maybe I read it wrong lol. Too many internet pages opened on phone haha

Also, do you have the same Tao model we have ('New Cheetah') as shown in the photos, or do have the older, original, 'Cheetah' model? If you have the older 'Cheetah' model then everything I have added to this thread does not apply.

[Boosted19]

Brand new. I think the websites are measuring differently. The link you sent they are probably measuring from bolt to bolt. (Around axle) bc I just measured my stock sprocket and just about 2” from hole to hole going outside of axle. And whygostock and Taopartsdirect is measuring from hole to hole across axle hole. That make sense to you? Lol I’m bad at explaining stuff hahah

[Boosted19]

And it’s actually a nitro. But came in cheetah box haha. Here’s link to what I got. https://q9powersportsusa.com/collect...owersports-usa

[GrandKidsMX]

Originally Posted by Boosted19

And it’s actually a nitro. But came in cheetah box haha. Here’s link to what I got. https://q9powersportsusa.com/collect...owersports-usa

That's not the same machine we have. I have no idea about parts interchangability between the 'New Cheetah' and the model you have.

Best thing for you to do is measure everything (like you just did), and then hunt-up parts that will work for your model.

That's one of the biggest problems with these China brand bikes/quads is parts availability and compatability.