View Full Version : Help needed

23-Nov-09, 03:31 PM
Hi guys am hoping someone can help me with some advice. I was playing with my hovercraft when it lost all power. engine is a 250 bultaco two stroke, it still turns over but no sign of firing. I have checked spark and that is strong fuel is getting to cylinder am at a loss. any suggestions gratefully received

23-Nov-09, 04:35 PM
I raced one once when it ran !!! they regularly blow the crankshaft oil seals which are a separate bolt on item. Also check the points gap, and compression as they only have one piston ring on the very top of the piston and they often break so start checking.
Is i a persang or a trials based motor??


23-Nov-09, 05:07 PM
i used to have a bultaco 250 trials bike, was a bit heavy for me at 11 yrs old lol. me an it almost went down a mine shaft on madron carn when i was 12, dropped it and slid down the mouth of the shaft and got stopped by a bush.

to the point! was always a bugger to start, infact had to start on a soft plug and change to a hard plug when hot.

check compression!

not a lot of power from one of those things, lots of torque, but its a bit of an old thumper engine!

24-Nov-09, 07:40 AM
cheers guys
am getting tools ready to start fettling.