astroarjun

I wonder what should I suggest?

I said that its chain pitch is same, but I can't confirm fitting.

Anyways, why don't you try the rear sprocket of Zues or Fiero F2? 40 teeth they are, both of them.
Chain pitch matches, but can't confirm fitting.

I wonder what should I suggest?

I said that its chain pitch is same, but I can't confirm fitting.

Anyways, why don't you try the rear sprocket of Zues or Fiero F2? 40 teeth they are, both of them.
Chain pitch matches, but can't confirm fitting.

That's why I told that you should first try it before purchasing.

Anyways, I suppose you can get the fitment holes measured & drilled accurately, in such a way that it fits without any loose fitting either side.
The bigger thing is the chain pitch - I'm sure it matches...

If you observe keenly, drop in acceleration would be noticeable... But it won't be too much of a difference.

Try one of the bikes' front sprocket that I mentioned. I believe it must cost around 70-80 rupees at most..
Maybe RX135's might cost more, because its spares might be supplied less...

Also, get the chain adjusted for an ideal, 35-40mm play. Chain will be adjusted after changing sprocket...

I see... maybe I keep it for longer times upto that rpm, so I see more.

Do check whether your rear has a 43 or 44 teeth. Stock P180 should have 43 at rear and 15 teeth at front.

Anyways, 42 teeth won't bring a significant difference. Mostly upto 1-2 kmph only.

40 teeth will bring you the 4-5 kmph difference you need. Like I said, try both Suzuki Zues OR Fiero F2's rear sprocket and see which one fits... I'm sure one of them should.

In your bike, 1 teeth change at front will bring almost the same change as 43/15 which is equal to 2.86 teeth at the rear. Almost 3 teeth.

So, a 16 teeth gives you same 4-5 kmph increase, but very less bikes have 16 teeth in front... Latest eliminator, or the RX 135 has 16 teeth up front with a 428 chain pitch.

Good thing about front spr. change is less cost, less adjustments to chain needed. Its your choice.

See, 50 @ 4 krpm is fine but it does 65 @ 5 krpm & 75 @ 6krpm, 100 @ 8 krpm

If it does less speeds then these, then get you clutch plates checked specially if they have been heavily used for stunts or crossed 20 k-kms.

About the sprocket setup, you can do these:-->

1. Older P180 UG2 came with 42 teeth sprocket... It will mildly increase top end & mileage, with no noticeable effect on acceleration. It's a direct fit!

2. Either of Suzuki Zues OR Fiero F2's sprocket MIGHT fit, and they are 40 teeth each. It will give noticeable effects. Accd. to my calcuations, on 40t sprocket you should get 53.5 @ 4krpm and 69.6 @ 5 krpm (instead of 65, that is).

I can NOT confirm whether they will fit or not. So, try it before you buy it... ok?

But First, get checked that why do you get 61-62 instead of 65...? Good luck.