poping and backfiring

[mastro490]

It a 99blaster with a yz 490. I just put new piston and rings in it. Kick it over and there was some poping and backfiring when i kicked it, but the motor was not running. It did that for about the first five times i tryed to start it. Put a little gas mix in the carb and would not start. But i used starter fluid and she came alive. Any idea about what this could be guys

 

[jus_me]

First off be easy on the starting fluid. There no oil in starting fluid. Have you checked the reeds? are you using fresh gas? Have you cleaned the carb ?

 

[mastro490]

First off be easy on the starting fluid. There no oil in starting fluid. Have you checked the reeds? are you using fresh gas? Have you cleaned the carb ?

The reeds look good, fresh gas and oil, and i cleaned the carb. Got new jets ordered. The only thing i can think of is i got a hole at the the pipehead

 

[Herpderplol]

Thats probably your problem... not enough back pressure.

 

[tbrooks]

or timing

 

[Larry's Shee]

Have you leak down tested it?
Flywheel key good?
Piston in correct way?
Correct sparkplug?New?
What does the spark look like?

 

[mastro490]

Spark is great and a brand new plug. The timing is set right. Backfiring and poping has gone away. So i just dont know

 

[Larry's Shee]

Round two; Have you done a leakdown test?