charliep1982 Posted April 7, 2011 Share Posted April 7, 2011 As usual HELP!!!!!! my yb had just passed its mot, then it began missing at the top of second third and fourth. Then throughout third and fourth. it slowly faded from there. Now it just won't start. I have checked the spark and it looks good, I have looked at the fuel system and again looks good. Spoke to someone who suggested the condenser. Is this possible and how would I check. I appreciate that you guys have much more knowledge and experience with these (usually) great bikes, so any input is appreciated Link to comment Share on other sites More sharing options...
charliep1982 Posted April 24, 2011 Author Share Posted April 24, 2011 Ok so I have changed the condenser and still nothing. I am definitely getting fuel to the cylinder as proven by what a friend called the match test, spark still looks good. Someone has suggested overfuelling/flooding how do o overcome this? Pilot screw is set at 1 1/2 turns but no luck. Kicked bike over for a while and got a big pop (with flame) from the carb which was open at the time. With this nice weather I am desperate just to go for a ride. Please any ideas? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted April 24, 2011 Moderator Share Posted April 24, 2011 Its always good to take the plug out, stick a pencil down the plug hole to touch the piston and turn the engine with the kicker until the piston is at the bottom of its stroke, then leave it overnight with the plug still removed. That way any fuel in the crankcase will evaporate out. try again with a new plug and if you're lucky... Link to comment Share on other sites More sharing options...
Moderator drewpy Posted April 25, 2011 Moderator Share Posted April 25, 2011 heating the end of the plug up help with a recaltriant engine Link to comment Share on other sites More sharing options...
JimR Posted April 28, 2011 Share Posted April 28, 2011 Its always good to take the plug out, stick a pencil down the plug hole to touch the piston and turn the engine with the kicker until the piston is at the bottom of its stroke, then leave it overnight with the plug still removed. That way any fuel in the crankcase will evaporate out. try again with a new plug and if you're lucky... Not with the YB the disc valve will be in such a position that will not to allow not allow the fuel evaporate Link to comment Share on other sites More sharing options...
JimR Posted April 28, 2011 Share Posted April 28, 2011 Ok so I have changed the condenser and still nothing. I am definitely getting fuel to the cylinder as proven by what a friend called the match test, spark still looks good. Someone has suggested overfuelling/flooding how do o overcome this? Pilot screw is set at 1 1/2 turns but no luck. Kicked bike over for a while and got a big pop (with flame) from the carb which was open at the time. With this nice weather I am desperate just to go for a ride. Please any ideas? I guess you need to set the ignition timing .. if the condenser is giving problems .. the motor will run but misfire if you add load to the mag (switch the lights on) but if you want to test a condenser just test to 22 microfards across the unit then charge it up & then discharge ... But another thing YB100 suffered with was 'loads of carbon' you may find that the rings have stuck or the bore has been 'glazed' with carbon and your problem is lack of compression. Don't forget if you remove the mag you must set the ignition timing Link to comment Share on other sites More sharing options...
wild foamy Posted April 29, 2011 Share Posted April 29, 2011 Test the compression, gauges are available that screw into the plug hole to perform such a test, they arent expensive and worth the money, - Foamy *thud* Link to comment Share on other sites More sharing options...
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