VTR250 won't run

**Sebastian Thornton** · 24th September 2010, 15:46

I was riding in the Wairapa the other day when I suddenly lost power. Whenever I put the clutch in I could feel the engine stalling So I trid no to stop until I got to featherston but eventualy had to stop in Martinborough where it eventually stalled. Whenever I try to get it started it starts, sometimes revs but never idles. after a while it just stops. Ive checked the plugs and they are black and dry but there is plently of fuel in the carbs. Can anyone help?

**MSTRS:Me** · 24th September 2010, 17:47

I suspect that you have several things going on, but black plugs on a warm engine are not right, for a start.

Top left shows normal...

Is your airfilter clean? Choke working properly?

**FROSTY:Me** · 24th September 2010, 18:36

working on the kiss principle--Did you knock the choke lever on by mistake. maybee knock the fuel tap?-often sudden issues are silly stuff

**Sebastian Thornton** · 24th September 2010, 21:46

Choke works fine. The diaphram on the tab wasnt springing back but i fixed that but same problem with the engine. I gave the air filter a clean and even tried starting it without it but same thing happened. I emtied the carbs and they both had plenty of fuel. Im starting to suspect a blocked jet. What do you think?

**MSTRS:Me** · 25th September 2010, 09:06

That would mean the engine runs lean. Which is not what black plugs are telling us. Putting aside the condition of the plugs for a moment, you have one carb per cylinder. Possible to have the same blockage in both at the same time, but not hugely likely. The engine would run, but not well, on one cylinder. In which case, you'd be seeing plugs which do not match in colour.
It is possible that your problem is electrical (coils?) and you are not getting a good, strong spark. Which means incomplete combustion = poor running, black plugs.

**Sebastian Thornton** · 28th September 2010, 21:21

Ive checked the coils and what not and the spark seems good. Today I checked the valve clearances and they were very tight. So tight in fact that i couldnt get any feeler gauges between the valve stem and the tappit. I will put it back together tomorrow and hopefully thats solved the problem!

**Jonno.** · 28th September 2010, 22:17

Are you sure you're placing the guages in the correct place and that you're measuring when it's at TDC? That sound rediculously tight and more likely you're measuring when it's not at TDC.

**Sebastian Thornton** · 12th January 2011, 19:06

Turned out it was nothing to do with fuel and the bike had siezed

**Gibbo89** · 13th January 2011, 11:03

Originally Posted by Sebastian Thornton

Turned out it was nothing to do with fuel and the bike had siezed

How the hell did that happen? What does it mean if a four stroke engine has seized? I know 2 strokes do it more often but is the engine fully fucked now?