Stephen Kelley Posted November 24, 2009 Share Posted November 24, 2009 Hi guys, i'm new to the forum, and i really need some help with my bike. I bought this TZR 125 a few months ago, the fairing were all smashed, but it was a good runner. So we've repaired the fairings, and now it will not run properly. The first problem is that it will not start off the button, but will usually start off a bump, which is no big deal because its easy to bump. But since we've repaired and sprayed the fairings, the damn thing will not run. When its stationary on the side stand it will tick over and run, but not rev freely. But when i try to ride it it revs to about 4k and misfires and after a few seconds it will cut out completely. Ok, so.. things we've checked: Spark is fine Carb is fine with new standard jets Petrol tap is working fine, seems to be fueling correctly Inlet manifold checked to ensure no leaks, new gasket and sealer just to be sure Powervalve seems to be working correctly, goes through its self adjustment thing when ignition is turned on and turns when revved What we havent checked.. because we don't know how: Electrics - coils, cdi etc. Mechanical stuff we're fine with, wiring we aren't so good. Timing (not sure if it can be adjusted) And anything else we should have checked but isn't on this list hasn't been checked because we either didn't know about it or didn't know how to check it. Things we haven't checked because we either think its an unlikely cause of the problem or a big job that we hope it isnt: Head gasket, i know it can cause misfires if its losing compression. (We haven't done a compression test as yet because we can't find our compression tester). And i can't think of anything else, i've been as thorough as i can manage. We built this bike back up for my 17th birthday (Friday just gone), and as of yet i've not been able to use the bugger! Any help appreciated Ste Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 24, 2009 Moderator Share Posted November 24, 2009 First and slightly patronising question, you have got a full tank of good fuel. When you say the carb is good with new std jets. What was in it before. Have you had the tank off, could you have trapped a breather or kinked a delivery pipe. That would be my first line of attack. Removing the fairings doesent entail disturbing all that much as far as the vitals of the bike go, the main electrics live under the seat as i understand and again would not be disturbed. If it ran fine BEFORE you messed with it you must have caused the problem. If the ignition was right before then it still will be you need tools to change it, same goes for the head gasket. Link to comment Share on other sites More sharing options...
wizzer Posted November 24, 2009 Share Posted November 24, 2009 When its stationary on the side stand it will tick over and run, but not rev freely. But when i try to ride it it revs to about 4k and misfires and after a few seconds it will cut out completely. [/code] Just a thought but is the carb on vertically, if its at an angle it would efect fuel level in the bowl, as you said it runs on the side stand Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 24, 2009 Moderator Share Posted November 24, 2009 is the fuel tap a vacuum operated one, if so did you refill the carb by switching to 'PRIME' ? is the vacuum pipe back on the manifold and with a good seal ? Link to comment Share on other sites More sharing options...
Stephen Kelley Posted November 25, 2009 Author Share Posted November 25, 2009 Thanks for the replies guys. I checked all the pipes to make sure none were kinked or pinched, all seems fine. We haven't changed anything apart from taking off the fairings, and like you say, should not have disturbed anything. We did think of the carb positioning and tried it last night, the carb sits vertically when the bike is vertical (paddock stand). I'm not sure if the tap is a vacuum operated one, but i cannot see any pipes disconnected that should be connected and there aren't any leaks from the manifold so i'd be inclined to say it isn't, but i will double check again just to make sure. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 25, 2009 Moderator Share Posted November 25, 2009 Thanks for the replies guys. I checked all the pipes to make sure none were kinked or pinched, all seems fine. We haven't changed anything apart from taking off the fairings, and like you say, should not have disturbed anything. We did think of the carb positioning and tried it last night, the carb sits vertically when the bike is vertical (paddock stand). I'm not sure if the tap is a vacuum operated one, but i cannot see any pipes disconnected that should be connected and there aren't any leaks from the manifold so i'd be inclined to say it isn't, but i will double check again just to make sure. Is the battery any good, i have heard that a dodgy battery can cause some weird problems on the TDR/TZR 250's don't see why the 125 should be any different especially as you say it won't go off the button. Link to comment Share on other sites More sharing options...
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