• Well he s a nother one for the gurus we had one of our bikes die last week hole...

    Well he's a nother one for the gurus, we had one of our bikes die last week , hole in the piston, any who after I reassembled it, started first kick, ideled like a new one, took it for a blat up the road to make sure all was good, accelerated OK but a bitdopy, didn't want to pushit as it was a brand new rebuilt engine. As I settled down to cruise at around 50 km the thing developed Huntington's , dieing and surgeing etc. Any ideas , I already solved it but I'm wundering if any one has ever had the same problem.

    13 comments
    • cantankerous machine that hates wet Wednesdays... oh wait - that's Mo

    • We had to rebuild it because of tepiston, chain your getting close , I would expect nothing less from a mechanic of your calibre.

    • something rubbing ? rear tyre ? rear brake shoes ?...its difficult over the interweb..:)

    • Timing chain jumped

    • I was about to suggest Cam Timing... :D

    • Head gasket leak

    • Yup, cam timeing, 3 teeth out. Retarded, it was a wonder it ran....

    • If that was the case it would not run bad then good

    • So were you setting up the timing by the timing marks or cam position with the piston on TDC?

      Once had a mechanic who spent all day trying to get a CB175 to run. Turned out the cam chain sprocket was off another model, marks in a different place.

      However if we assume that yours was set up correctly, the cam chain and sprockets are matching pitch.

      The most likely scenario is the engine was rotated backwards while in gear causing the chain to jump a couple of teeth

    • The reason it happened is I'm very long sighted and my eyes are dimming, so I was relying on Annie's eyes to see the marks , I put in DC and then slipped the can shaft in till both rockers were loose the can bolt lined up with the O and both were still loose did it up and it turned over without the valves touching, did it up and it ran well. But I was 3 teeth out when we checked it later , I don't think the the cam chain adjuster could move it away from the marks that much..... moral :: don't let me work on your bike.......

    • I once rolled a Hi Ace van backwards, engine off and in 1st gear, let out the clutch instead of braking and the cam timing went out.

      That's why I made the supposition above.

      Some workshop manuals recommend rotating the engine a few times and rechecking the timing marks.

    • I'm pretty blind, it was my fault, I think Annie could see the marks but they weren't what I assumed her to be seeing , did it out in the sun the second time and I could just see them with a mag glass.

    • Well I'm assuming retarded, I had to move the cam sproket clockwise 3 teeth to get the marks to line up.