Engine trouble

Gagesblaster

New Member
Feb 15, 2020
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Just picked up another blaster...not sure the year....only thing wrong was the rings destroyed the piston....dude said it was bored over....i didnt have a micrometer to find out size so i ordered a stock piston because i had a stock top....bike fires right up idles good....but its sputters until i get the rpms up....cannot figure it out
 
whats the compression of this new top end ?
did you do the heat cycles then re-torque the head/base bolts ?
check for airleaks with a leakdown test, as all new build should be
clean the carb ?
just for starters
 
What was the numbers on top of old piston
? Ussualy will have piston size engraved on top. (66.00) example for stock bore piston
 
whats the compression of this new top end ?
did you do the heat cycles then re-torque the head/base bolts ?
check for airleaks with a leakdown test, as all new build should be
clean the carb ?
just for starters
My buddy let me borrow one of the gauges to check it....took it for an actual ride today and retightened once i got home and ive cleaned carb....looks brand new....once u get the rpms up it runs like a beast....but 5th and 6th gear doesnt run the best
 
My buddy let me borrow one of the gauges to check it....took it for an actual ride today and retightened once i got home and ive cleaned carb....looks brand new....once u get the rpms up it runs like a beast....but 5th and 6th gear doesnt run the best
What were the jet numbers in carb?
 
Also check air cleaner. Float height could be off.do plug chops to confirm jetting is very important.so this piston doesn't fry!!what carb is on it.is it the stock carb?
 
So bore is 66.75mm. Last 4 digits is piston size ussualy on these pistons.what size did you put in?
Stock size because i had a couple stock jugs...and its a stock carb needle and jets...i took insides of of my other blasters carb
 
Stock size because i had a couple stock jugs...and its a stock carb needle and jets...i took insides of of my other blasters carb
What's the numbers on the jets.leakdown test?as mentioned earlier.there is usually a reason That piston looked like it did.what clip position is needle on in carb. Usually middle position works on most stock carbs