Run's Well,but Wondering.............................

geebt48cc

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What Is The Greatest PERformance Modification For A Stock 49cc 2/Stroke Engine? .....skyhawk,400 Miles,25/1mix:d

Ty/glen
 
two words: expansion chamber

I'm going to get a shift kit, actually all those that have ordered the roller bracket from me are buying it. I want to thank them all, but back to the subject....on a scale of 1(low) - 10, where would you place the expansion chamber and a shift kit, and why.

Now as to what I'm looking at is not speed as my bike will go faster WOT then I can for any length of time. It's plenty fast enough to go on a bicycle made for less then 10 MPH. I'm looking at the fact that with a shift kit I can attain my normal speed of 10-15MPH at a lower RPM with the shift kit, thus extending the life of these engines. What say you Paul?
 
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I'm a bit strange, I don't actually consider the shift kit a "performance modification". The reasoning is this:

a) it doesn't change performance so much as it's so completely different, I mean converting an AT to MT in car (which I have done) is less drastic. It's not a modification. It's a......I dunno...renewal, revolution, complete do over. That said it will get you from zero to 35 way faster than any bolt on sprocket bike, so for that reason it's a 10!

b) Even with a shifter kit, you will still want the cool stuff like roller clutch, expansion chamber, higher compression, ports matched to mani's....etc...so for bolt on performance mod, there still is nothing better than an expansion chamber on a 2 stroke. 10.
 
I have a 49 c.c. slant head on a 20" frame with 20" wheels.
the biggest performance upgrade that i have made is by adding an expansion chamber and a high flow air filter.
But, carb tuning is a huge thing with these engines. getting the carb just right is another key to performance.
a better spark plug wire, boot and an ngk spark plug will also add a little power. another thing that a lot of people forget about is indexing the spark plug. you need to get indexing washers to do this, but basically you align the opening of the electrode on the spark plug directly in like with the path of the intake. this takes some trial and error and messing with the indexing washers but it will add a tiny bit of performace. is it really worth the effort? probably not to everyone, but i did it.
I have also dropped from a 44 tooth sprocket to a 41, only because i am using the small 20" wheels. the 41 tooth gives my bike a little more top end, but the biggest improvement by going to the 41 tooth sprocket is the mid range.
with the 44 tooth, the engine would reach it's peak torque way too soon (it would wind out too fast). now with the 41 tooth, it still has plenty of bottom end take off, but the midrange pull has greatly increased. the torque curve is not so ,uch a peak now, it;s more of a flat line and it pulls longer and harder.
milling the stock head will raise the compression, or you could just buy a billit high compression head.
also, yiur fuel/oil ratio will make a big difference in performance. i found that running 32:1 makes the most power for me....and i use synthetic 2 stroke oil and 87 octane regular gas.
 
What ???????????

A two stroke with supercharger and turbo??????? never heard of one:sick:
IT would do 1MPG and the exhaust would be full of unburned fuel, it would fill up a swiming pool of fuel in 2 minutes!
SUPERCHARGER + 2 STROKE = WASTE OF FUEL + MONEY , SUPERCHARGER + TURBO + 2 STROKE = WASTE OF TIME, MONEY AND FUEL
G-Superior :D
 
G superior .................it was a JOKE...... as for the unburned fuel just throw a a fan and a extra spark plug back there 2 stroke+supercharger+turbo+sparkplug+fan = one fast ride with afterburner...........and it would be badass......top fuel dragsters get not even one mile to the gallon but there still cool and badass!!!!
 
A two stroke with supercharger and turbo??????? never heard of one:sick:
IT would do 1MPG and the exhaust would be full of unburned fuel, it would fill up a swiming pool of fuel in 2 minutes!
SUPERCHARGER + 2 STROKE = WASTE OF FUEL + MONEY , SUPERCHARGER + TURBO + 2 STROKE = WASTE OF TIME, MONEY AND FUEL
G-Superior :D

actually, some firetrucks use 2 stroke diesel's with a supercharger and a turbo. the turbo blows into the supercharger.
these engines are very efficient and make HUGE torque numbers.
 
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