Suzuki DF15, backfire and difficult start

[Arno1969]

Hi, newbie from Holland so please understand that my English is not perfect !

I bought a Suzuki DF15 from 2002. Engine cold starts OK with choke.

When running it in neutral (in a bucket) it backfires when I give it full throttle suddenly. When opening throttle slowly it accelerates normal. Also noticed that when running it with 10% throttle (in de bucket) it sometimes backfires just like that (without touching anything) ??!!??

I aso noticed that the engine will only start with choke ! Even after running for 30 minutes and hot engine, it only starts when I use the choke.

Anyone any idea what causes the backfire and why his engine can only start with choke. (Is handstart by the way)

Thanks
Arno

 

[99yam40]

Re: Suzuki DF15, backfire and difficult start

1st thing , it is not good to run a 2 stk at high RPMs in neutral, so do not do that.
2nd - back fire/lean sneeze is a sign of running lean, I would clean the carbs

 

[Arno1969]

Re: Suzuki DF15, backfire and difficult start

Thx for the answer. I know it is not good to run the engine on high rpm in neutral, I just give it some throttle to test and do not let it run on high rpm.

Is backfire (or lean sneeze as you call it) a lean mixture problem only ?? I tried to adjust the different screws on the carb to see if the situation approved or got worse but it did not have any result.
Could it be a timing issue as well or with cdi ignition and variable valve timing this doesn't happen ??

Thnx,

Arno