Search results

  1. Q

    Bike backfires and pops during start up

    Get a room lads. Preferably a sound proof one. Haha I agree and disagree with both views since I put the liquid gasket between the carb and gasket not the engine /gasket side after using wet and dry paper on all relevant surfaces. I can be reasonably sure that there are no air leaks there. Since...
  2. Q

    Bike backfires and pops during start up

    That ks for the input skull. When I took the 76/77 carbs off to put the 74/5s on I noticed that the brass fitting on the fuel crossover tube on one of the carbs was loose and was only held in by the rubber tube could have been causing the air leak. Anyway for now I'm happy with the 75s im close...
  3. Q

    Bike backfires and pops during start up

    The left carb was not working as well as it should have so I pulled it and found that the floats were set at 27 mm so I corrected it. while I was looking at the bike without the carb on I noticed that the right breather tube was leaking quite a bit of oil onto the choke crossover tube. Is this...
  4. Q

    Bike backfires and pops during start up

    The main jet on European models differs from U.S. counterparts. my conclusion on the identity of my carbs came from this site http://www.xs650.fi/pohja_files/fi/XS650carbs.htm as far as I can tell the main jet is the only real difference between the two. My needles are correct and correctly set...
  5. Q

    Bike backfires and pops during start up

    Let's say I have a set of European model bs38s circa 1974/5 dual throttle cable barrel style cable loops. They had 120 mains on it and 45 pilots. There were parts missing off the carbs like jet needles so I bought new ones from mikes xs. My bike is stock 72 us import with paper filters from what...
  6. Q

    Bike backfires and pops during start up

    Thanks for the help peanut one again you have come to my rescue. I did what you said. I removed the carbs and boots, wet an dry paper on both the engine side and boot, put new gaskets on with liquid gasket between the boot and the gasket surface. I have a set of brand new 74/75 bs38s with dual...
  7. Q

    Bike backfires and pops during start up

    Ok since fixing the choke I seem to be running very rich now. There's quite a bit of soot on the plugs but the business end of the plugs are white so lean pilot circuit rich midrange. I will move the needles back to no 3 slot On the way to work today the bike started surging in rpm and wouldn't...
  8. Q

    Bike backfires and pops during start up

    Read the carb guide back to front and back again. I'm scratching my head because i didn't have these carb problems before the rebuild. I replaced the r/h crank bearing,all of the cam bearings and the cylinder sleeves.
  9. Q

    Bike backfires and pops during start up

    The choke system wasn't working because the screw in the linkage arm of the second carb was missing so I was in effect only enrichening one carb. Choke fixed but still popping throught carbs for first few mins of riding then overheating slightly after about 10 miles. Can't find the leak. I've...
  10. Q

    Bike backfires and pops during start up

    Scratch that no it doesn't start any better. Still have to coax it into life
  11. Q

    Bike backfires and pops during start up

    I've cleaned the enrichener circuit, took float bowls and fuel screws out and blew air and carb cleaner in every orifice. Bike starts better but still running lean. Atu is good and correct and working properly. Not sure what else to look at
  12. Q

    Bike backfires and pops during start up

    This may or may not be related to carbs but I'll throw this out there. I've just finished a rebuild of a stock 72 motor. It has 76/77 carbs on it which had one size up on pilot and one size on mains which ran fine before the rebuild. Since the rebuild she is running rediculously lean. She...
  13. Q

    New engine blows head gasket

    @grizzld When I put it back together and ran through the heat cycles it was fine the I retorqued it after the next set of heat cycles it started to run v lean like there was an air leak somewhere. I couldn't find the leak and I overlooked the head gasket. I suspected that the heads weren't...
  14. Q

    New engine blows head gasket

    Think I already know the answer to this question but I thought I'd throw it out there anyways. I put my engine back together after replacing the cylinder sleeves and bearings in both the top and bottom end. I went through the heat cycles that we associate with a new build and retorqued. About...
  15. Q

    Cylinder sleeve rebore

    Thanks for putting the shits up me kop. I have a machinist doin the work now as we speak so we'll see. when I first run the bike am i putting it under load or just at idle for the first temperature cycle
  16. Q

    Cylinder sleeve rebore

    A wise old man suggested that it should be 75 mm plus two thousands of an inch fit the Pistons with the rings and if too tight go up to three thousands and no more. Any truth??
  17. Q

    Cylinder sleeve rebore

    Hello fellas wondering if someone knows the answer to this question I have just bought a set of cylinder sleeves grime Heiden tuning standard size. They came as 74 mm sleeves with the instructions to be rebored after fitting. The question is that is the standard bore exactly 75 mm to fit 75 mm...
  18. Q

    Whiring noise from bottom RH case

    If it ain't broke don't fix it... Thought about doing a rephrase but I had a mechanic look at the crank and he said it's all good. So I'll not be going down that expensive road yet. Heiden tuning do the sleeves but I think they need to be honed after fitting. The cylinder was cracked around the...
  19. Q

    Whiring noise from bottom RH case

    oh bad news was that while i was stripping it i found out that one of my clyinder sleeves was cracked so that means new piston rings, sleeve and rebore
  20. Q

    Whiring noise from bottom RH case

    gentlemen, been a while but i have some good news and some bad news. the good news is that after eventually stripping the engine i found out that the right ball bearing on the crankshaft was shot and not the roller bearings that cost 100 dollars each. grand so i can find the ball bearing for 18...
Back
Top