Fixie Thruster motorized bike build

[a0201618]

I bought a Fixie Thruster to put the kit on and I was wondering since there is a sprocket on both sides of the hub could I replace the fixed sprocket with a 44t instead of bolting the one that is with the kit on? I would much rather just replace the one on the motor drivetrain side with a 44t. Thankyou The motor kit is an 80cc..

 

[reb1]

How about more info on the motor kit.

 

[gymratdaddy]

If you find a threaded 44 tooth let us know... but yes, you can. I found a 22 tooth on ebay, largest I could find.

 

[a0201618]

If you find a threaded 44 tooth let us know... but yes, you can. I found a 22 tooth on ebay, largest I could find.

Did you use the 22 tooth? Or is that too much for an 80cc motor?

 

[gymratdaddy]

No... the stock 40 tooth is too small IMO on these bikes with the tall tires.

 

[a0201618]

No... the stock 40 tooth is too small IMO on these bikes with the tall tires.

Too small? Some people run theres with a 28 tooth? And also do you think I could find a threaded 32 tooth sprocket?

 

[a0201618]

I just ordered a threaded 36 tooth sprocket.. That should work right? and I should have a higher top speed with lower rpms needed?

 

[longo3]

I used my dremel to make the sproket hole fit on the fixed cog and bolted the motor's sprocket directly onto the fixed cog. The bolt holes lined up perfectly with the cog teeth. This entire bike is built for these motors- The right size pipes, sprocket ready to bolt to fixed sprocket(with just a little dremel), and lots of room in frame.

 

[george_n_texas]

I just wonder how much better the quality of this axle is and would it be able to be put on most bikes??? http://www.niagaracycle.com/product_info.php?products_id=441870 I'm hearin the WM Fixie has a really cheap rear axle

 

[a0201618]

Will the threaded 36 tooth work?

 

[george_n_texas]

Well if it's the one I saw on Niagra I doubt it the chain is way wider than a bike chain and so is the sprocket that comes on the engine so I'm guessin it'll slip off. Here are a few other considerations: the less teeth means higher speed at top end but lower torq at low end which means a lot of peddle assist. The fixie has a very large wheel 700c so I'd go with the biggest sprocket that will fit. I weigh 240lbs so low end torq is important.

 

[locell]

I used my dremel to make the sproket hole fit on the fixed cog and bolted the motor's sprocket directly onto the fixed cog. The bolt holes lined up perfectly with the cog teeth. This entire bike is built for these motors- The right size pipes, sprocket ready to bolt to fixed sprocket(with just a little dremel), and lots of room in frame.

"a little dremel" what did you dremel out? I did this same exact thing on the same exact bike but ts came out where the sprocket was not centered. Although solid, it goes up and down when spun

 

[george_n_texas]

If it goes up & down it's gonna wear out your chain in a hurry gotta be centered...I filed the inside of one of my sprockets to make it fit over the outside of the hub but I did it by hand with a curved file (the back side of a flat file) and frequently put it back on the hub to take just a bit of material off at a time to get it centered.

 

[locell]

If it goes up & down it's gonna wear out your chain in a hurry gotta be centered...I filed the inside of one of my sprockets to make it fit over the outside of the hub but I did it by hand with a curved file (the back side of a flat file) and frequently put it back on the hub to take just a bit of material off at a time to get it centered.

ok ya the only thing i have installed on the bike is the rear sprocket, I dident want to run it out of center like that.

It did require some filing etc to get it to be perfect center? I unscrewed one of the covers on the hub and dropped the 44tooth right on top of the factory "fixie" rear sprocket, i thought it would be centered by default but it wasnt

 

[george_n_texas]

Norm used broken ends of spokes as spacers to center his then bolt it down, I never tried that mine was to small of a hole. It wasn't a fixie.

 

[longo3]

500 miles on it now. The motor has ate a magneto, shot the muffler cap, and on and on and on. I think you got more to worry about with the motor then the hub, I cant bend it. Its a tall road bike on all road no jumps. 36 will give you more top end but less hill pull. kits sproket will start up a quarter mile 45 degree hill at 35 and be at 25 at top.

 

[reb1]

120mm is a standerd for fixies but I would measure the width being that it is a low end bicycle. The quality of the hub is better than your stock hub also.

 

[a0201618]

Well if it's the one I saw on Niagra I doubt it the chain is way wider than a bike chain and so is the sprocket that comes on the engine so I'm guessin it'll slip off. Here are a few other considerations: the less teeth means higher speed at top end but lower torq at low end which means a lot of peddle assist. The fixie has a very large wheel 700c so I'd go with the biggest sprocket that will fit. I weigh 240lbs so low end torq is important.

Do you or anyone else know where i can get a custom made 36 tooth thread on sprocket that is wider than normal bike sprockets? Here is the link to the sprocket i ordered... http://www.pocketbikeparts.com/Sprocket_Threaded_36_Tooth_p/rksp302185.htm .. Its from a pocket bike website so mabye it is the wider toothed one?

 

[longo3]

I had to dremel the sprocket center hole. When I did I went fast in circles around the inside just till it fit over the factory sprocket , I guess I got lucky and took off metal evenly its perfect center. I like that 36

 

[longo3]

http://www.ebay.com/itm/bicycle-Mot...Cycling_Parts_Accessories&hash=item2c65e33a2d