Andy626 Posted January 23, 2011 Posted January 23, 2011 Hi all, as per my intro post trying to get back into riding again but it has been a few decades since I had to fix them. I recently was given an old 2 stroke 74 TY250 trials bike. It had been sitting in someones shed for a while but done the basic checks, etc and it has been running ok for the last few weeks until now. Now it won't kick over anymore and I can confirm the following... You'll have to excuse my ignorance as It's been a while since ive done this. Got spark (put new spark plug in) spark is good, every kick and looks strong. Petcock is fine, fuel is going into carb, thought I would take the carb off and clean it but when I opened it up I was suprised how perfect it looked. No varnish, jets, floats, etc were 100% clean and looking good! Fuel is getting to the spark plug. Confirmed this after taking the plug out after a few kicks and fuel was on the end of the plug. Looked a bit oily though? I am running 32:1 so I assume thats ok? Assume air is getting in too as the filter is ok, nothing seems to be blocked. Thumb over confirmed good compression, haven't got a tester on me though but seemed to be ok. I read somewhere that the kill switch wire on the bar could be fouling, I will have to double check that when I get home but I have taken it off the other day and pretty sure I didn't see any loose connections, etc....I will confirm this soon. Sorry about the long message, I'm just lost at the moment.....Got good spark, got fuel, got air, got compression? I did get it going a few days ago by adjusting the idle right to the start and gave it 1 3/4 turn out and it fired up. Ran for a few days but then left it for about 3 days and now can't start it. Thanks for any advice!
blackhat250 Posted January 25, 2011 Posted January 25, 2011 Hi andy, " well if you have a spark ,that rules out the faulty kill switch, and plug is wet, well thats strange , sounds like the fuel quality. change the petrol. if this fails i think compression low. Iv seen a bike barely start, wouldnt rev just died, took barrel off, piston rings stuck in grooves of piston ,
Andy626 Posted January 25, 2011 Author Posted January 25, 2011 Thanks for your reply... Drained the old fuel, drained the carby and ran it all out. Put new fuel in and ran it at 50:1 just to see if there was too much oil but no go. For the hell of it I put the old spark plug back in (looks about 20 years old) and it fired up first kick!!! What the???? Now It's running perfect...lol I have no idea, the other plug was brand new and is the exact same NGK spark plug with same codes, etc. I did have it running with the new plug a few weeks back but all I can think of is this new plug may have been dodgy???
Moderator Airhead Posted January 25, 2011 Moderator Posted January 25, 2011 Spark plugs can be so temperamental on 2 strokes, good you got her running.
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