wild foamy Posted January 1, 2009 Share Posted January 1, 2009 Hi everyone. have just fitted my big bore, was a P.I.T.A getting the exhaust nut off but i managed it in the end by heating it up and then undoing it. now, my main problem is getting the bloody thing back on!, every time i screw it on it just doesnt seem to find the threads, or it will screw on and tighten up, possibly because it is cross-threading, but no matter how much i jiggle it about and redo it i can never get the bastard thing on. i made sure its the right thread and im doing it the right way. but it just wont go! anyone got any suggestions? - Steve Link to comment Share on other sites More sharing options...
Moderator Airhead Posted January 1, 2009 Moderator Share Posted January 1, 2009 either run a tap down the nut or fit a new nut...and...run a die nut down the stud! There is another option,..Remove the offending stud and fit a new one or saw the head off a bolt and fit that, its risky though because you might shear if off and then youre in deep sh1t so unless it moves easily leave well alone! Link to comment Share on other sites More sharing options...
wild foamy Posted January 1, 2009 Author Share Posted January 1, 2009 erm, i think you mis understand. this is the nut that holds the exhaust manifold onto the exhaust outlet on the cylinder block, with the crushable washer inbetween the one you normally undo with a C-spanner Link to comment Share on other sites More sharing options...
Moderator Airhead Posted January 1, 2009 Moderator Share Posted January 1, 2009 erm, i think you mis understand. this is the nut that holds the exhaust manifold onto the exhaust outlet on the cylinder block, with the crushable washer inbetween the one you normally undo with a C-spanner erm, i think i did mis-understand yes, i assumed that it was the usual method of connection. If youve got that thing cross threaded youre in for trouble, you fitted a new barrel yes, so try it back on the old one, if it goes back on the old one there must be some imperfection on the thread of the new one and you will need to sort it out possibly with a thread file. If it doesnt go back on the old one you may have crossed it trying it on the new one which is V Bad news because you cannot remove it from the pipe if i'm right! Link to comment Share on other sites More sharing options...
wild foamy Posted January 1, 2009 Author Share Posted January 1, 2009 i loosened it off in my dads work shop and we wound it back on to the original bore to make sure i could get it off again when i got home to fit the big bore, took a while to get it right but it went on fine nonetheless. i have to go to work tomorrow morning so i will probably give it one last try before i head off, i work in the retail park about a mile to 2 miles away, will it damage the bike if i left it disconnected to the manifold? (obviously i would be taking it easy anyway because it is a new bore and i understand the mixture would be running a bit leaner than usual) and i hope i dont have to rpelace the nut, as that means replacing the whole expansion chamber... about £60-£70 Link to comment Share on other sites More sharing options...
Moderator Airhead Posted January 1, 2009 Moderator Share Posted January 1, 2009 will it damage the bike if i left it disconnected to the manifold? (obviously i would be taking it easy anyway because it is a new bore and i understand the mixture would be running a bit leaner than usual) and i hope i dont have to rpelace the nut, as that means replacing the whole expansion chamber... about £60-£70 Riding with it undone is not an option really, you cant risk it and performance will be bad as well Link to comment Share on other sites More sharing options...
JUST ME! Posted January 2, 2009 Share Posted January 2, 2009 Riding with it undone is not an option really, you cant risk it and performance will be bad as wellIf I have this right, you say it screws onto the original barrel OK. If it does, the nut must still be usable. Look at the male thread closely and prepare the start of the thread with a thread file. Leave the rest of the chamber mounted very loose whilst trying to get the nut started. This will give you more range of movement. When you get it aligned properly run the nut up and down the thread a few times without putting weight on the flange gasket, just to clean the thread. Out of interest let us know what capacity you have gone to and how it panned out. Don,t forget,you will most likely have to change the jetting! Keep an eye on the plug colour. ALL THE BEST WITH IT AND ALLTHE BEST FOR 2009. Link to comment Share on other sites More sharing options...
JUST ME! Posted January 2, 2009 Share Posted January 2, 2009 If I have this right, you say it screws onto the original barrel OK. If it does, the nut must still be usable. Look at the male thread closely and prepare the start of the thread with a thread file. Leave the rest of the chamber mounted very loose whilst trying to get the nut started. This will give you more range of movement. When you get it aligned properly run the nut up and down the thread a few times without putting weight on the flange gasket, just to clean the thread. Out of interest let us know what capacity you have gone to and how it panned out. Don,t forget,you will most likely have to change the jetting! Keep an eye on the plug colour. ALL THE BEST WITH IT AND ALLTHE BEST FOR 2009. Just a thought, are there less threads on the new barrel causing the flange nut to bottom out on threads before it compresses the flange gasket? Link to comment Share on other sites More sharing options...
wild foamy Posted January 2, 2009 Author Share Posted January 2, 2009 No theres plenty of threads on the flange nut, its just i can't get it to screw onto the head because it either cross-threads, tightens up and then i have to undo it and try again, or it just wont screw on, it can't seem to "find" the thread and get started. surely theres an easier way? ive enlisted in a VERY temporary fix, Heat resistant tape to keep the manifold aligned with the head. hopefully this should last the 5 minute journey to work but after that im taking it off the road until i can get it sorted Link to comment Share on other sites More sharing options...
wild foamy Posted January 2, 2009 Author Share Posted January 2, 2009 I gave it one last try... gave both the head and the nut a blast with WD40, then a wipe with some cloth, then another blast and another wipe, and after a bit more fiddling and adjusting of the expansion pipe i got it to go on . you'd be amazed at how much shite there was in those little threads thanks for the help, all Did have to adjust the throttle stop screw on the carb to get it to idle nicely, and now that ive got the pipe on it seems very smokey and asthough its running rich, when i put the choke on it dies so i doubt it is running lean, if i hold the throttle open for a while it will clear its throat and rev up like normal. am i doing something wrong or is it just because the new piston/sleeve hasn't seated yet? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted January 2, 2009 Moderator Share Posted January 2, 2009 Great news Steve, glad you havent damaged it, now buy or borrow a thread file and scrape that shite ouf of the threads on the nut, you wont get it out properly without one and it will end up jammed on again. Link to comment Share on other sites More sharing options...
wild foamy Posted January 2, 2009 Author Share Posted January 2, 2009 well i put about 5 miles on it, down into town and back again and now its absolutely fine, plenty of smoke coming out of the exhaust and although it does seem a bit sluggish when the revs drop it seems to be alright, will take it easy for the first 500 miles or so and once it has been run in i will get to see the real effect of my £40 big bore will keep an eye on the plug though, it was jet black when i took it off to change the barrel and it was way over-jetted when i got it because it had the aftermarket air filter and exhaust on EDIT: will do OG Link to comment Share on other sites More sharing options...
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