49cc razor pocket mod gear ratio

[kidgambit]

I'm gonna put a 49cc pocket bike engine I rescued and got running into a razor pocket mod frame. But a guy on YouTube did one and the stock rear sprocket is to big and makes it go slow. It is a 12 inch rim the engine has a 7 tooth sprocket. What tooth rear sprocket do I need to get more speed. Please help

 

[cannonball2]

Bigger sprocket on the trans or a smaller on the wheel. Trans is easier to change.

 

[kidgambit]

It has 45 tooth back sprocket and a 7 tooth on the transmission

 

[cannonball2]

Whats the transmissions reduction and the desired top speed?

 

[kidgambit]

I wanting to make it go as fast as it can

 

[kidgambit]

The stock sprocket on the 12 inch rim is 80 teeth

 

[cannonball2]

You didn't say what the transmissions reduction is. Some are 3:1 some are 5:1. Assuming a 3:1 If you ran a 14 on the trans and a 40 on the rear wheel and the engine makes 8500rpm the top speed is 35mph. You need to know which trans you have.

 

[kidgambit]

It has no transmission. Just a clutch with a 7 tooth sprocket

 

[cannonball2]

OK I assumed it was a CAG engine. Running what you have @ an rpm of 8500 is good for about 25mph.

I found a 10t on ebay for the front. Its cheap and easy to change. Used with your 80t rear it will get 37mph. This is assuming your engine will pull the ratio and will rev to 8500. That's pretty fast!!

 

[kidgambit]

Can I get a link please

 

[cannonball2]

You will have to determine if this fits what you have. http://www.ebay.com/itm/Mini-Pocket...271814115392?var=&hash=item3f49624040&vxp=mtr

 

[kidgambit]

How do u remove the sprocket of the clutch

 

[cannonball2]

It unscrews from the clutch drum.

 

[LongboardMalinois]

Just search ebay for 10t sprocket for whatever type of chain you have.