Only getting 22MPH (35KPH)

[CPC]

****, I have a question, Im only getting 22MPH full bore. I have a Chinese 66 cc engine with a 44 tooth rear sprocket. I want to get at least 35MPH with a cruising speed of 25MPH. Ive installed a NGK spark plug gaped to around .o2o greased the primary gears with blue marine grease, drilled a 1/4" hole in stock exhaust opposite of the primary outlet. Im running regular gas @ 20:1 put on a better air cleaner, but still have the 50cc stack carb. Any ideas how to increase my speed, I plan on getting a 36 tooth sprocket if this poor girl can come up on the cash and a good carb from spookytooth also. Thanks!

 

[bamabikeguy]

Breaking them in, with throttle variations, during the first 1-200 miles is vital to increased performance.

Did you do those steps, 10-20-15-30 seconds at various up/down throttle speeds?

 

[CPC]

never heard of such a thing! Not even researching here!

 

[CPC]

Ugh! I dont know what else to try....played with the carb to no improvement tightened the clutch up in case it was slipping, wasent. what else could it be?

 

[DetonatorTuning]

altitude, your high enough to be loosing 10+% easily, with out remedy.

sorry,
steve

 

[Mountainman]

break in -- hard to explain at times

Did you do those steps, 10-20-15-30 seconds at various up/down throttle speeds?

sounds like you may be ((past the break in period)) ???

it's always a good THING to do
although a little hard to explain at times
there has been much said regarding break in around here though

I kind of run from 1/3 to 2/3 throttle -- slowly up and down
when engine is new
turning it off every so often so as to cool off

ps -- running a little rich while breaking in -- always a good THING

just another ps -- don't climb any mountains while new -- unless I ((pedal hard)) to assist

ride that MB THING

 

[CPC]

sounds like you may be ((past the break in period)) ???

Ive got like 150 miles on engine. according to my calculations, Im only running @ 5000 rpm wide open.

I'm starting not to believe all these ppl here that say there getting 30, 40 50+ MPH, the math just does NOT add up! even with a 36 tooth sprocket you'll only get 31.4 MPH @ 6000 rpm.... I do not think these lil engines run that fast under load, just my opinion, recently formed.

 

[cooltoy]

With gears you could gain speed and still be able to climb hills.
You would not believe what a difference shifting gears can make.

 

[CPC]

ah i wanna, but I wont pay $200 for that kit from sickbikeparts

 

[lordoflightaz]

ah i wanna, but I wont pay $200 for that kit from sickbikeparts

Write it off as a business expense. You won't regret it Maybe get the 11 tooth sprocket as well.

Also, you could check for air leaks, intake exhaust and top end.

BTW right at 150 mile my top speed sort of jumped up while breaking in the engine. I hit 35 in 6th at less than WOT on a 49cc. Before that never really got over 28.