tzr92 Posted March 20, 2009 Share Posted March 20, 2009 I have a tzr 50 and my bike has recently broke down. When I take the bike up to 9000+revs it starts missing a lot which makes it drop 2 or 3 mph which makes a difference since i can only do 50mph. It does it most of the time but recently when it has started cutting out all together and the revs just drop until I stop and after that it is hard to start. the starter motor turns the engine over but it wont start. It will eventually start after 5 mins or so. Can someone help please. I have already changed the spark plug, plug lead, the coil and I have checked and cleaned out the carbuerator and connectors for the coil. I dont know what else to try. Link to comment Share on other sites More sharing options...
JimR Posted March 20, 2009 Share Posted March 20, 2009 I have a tzr 50 and my bike has recently broke down. When I take the bike up to 9000+revs it starts missing a lot which makes it drop 2 or 3 mph which makes a difference since i can only do 50mph. It does it most of the time but recently when it has started cutting out all together and the revs just drop until I stop and after that it is hard to start. the starter motor turns the engine over but it wont start. It will eventually start after 5 mins or so. Can someone help please. I have already changed the spark plug, plug lead, the coil and I have checked and cleaned out the carbuerator and connectors for the coil. I dont know what else to try. Hi, I would check the cdi and mag against the specs ... both cold & hot .... if correct cold & out hot you will need to replace the defective article .... but I would guess you have pickup/pulse coil problems Regards Jim Link to comment Share on other sites More sharing options...
tzr92 Posted March 21, 2009 Author Share Posted March 21, 2009 Hi, I would check the cdi and mag against the specs ... both cold & hot .... if correct cold & out hot you will need to replace the defective article .... but I would guess you have pickup/pulse coil problems Regards Jim I have not checked the magneto yet but i realised that when it is holding back or missing and i put the choke on it runs like it should and the revs pick right up to the redline but still cuts out sometime. So i figured it might be a fuel starvation problem but I have checked the fuel flow from the tank and it seems fine. Link to comment Share on other sites More sharing options...
tzr92 Posted March 30, 2009 Author Share Posted March 30, 2009 I have not checked the magneto yet but i realised that when it is holding back or missing and i put the choke on it runs like it should and the revs pick right up to the redline but still cuts out sometime. So i figured it might be a fuel starvation problem but I have checked the fuel flow from the tank and it seems fine. I put a colour tune in and it seems to be sparking fine so it cant be the magneto. any other ideas on what it could be? Link to comment Share on other sites More sharing options...
JimR Posted March 31, 2009 Share Posted March 31, 2009 I put a colour tune in and it seems to be sparking fine so it cant be the magneto. any other ideas on what it could be? Hi, I guess it's time to look at the carb just out of interest what colour did the colour tune show ? Regards Jim Link to comment Share on other sites More sharing options...
tzr92 Posted March 31, 2009 Author Share Posted March 31, 2009 Hi, I guess it's time to look at the carb just out of interest what colour did the colour tune show ? Regards Jim The flame was blue which im sure it is supposed to be. Although I have already cleaned my carb 3 times Im going to try another one on it. Link to comment Share on other sites More sharing options...
tzr92 Posted April 5, 2009 Author Share Posted April 5, 2009 The flame was blue which im sure it is supposed to be. Although I have already cleaned my carb 3 times Im going to try another one on it. Could it cut out if there was a air leak in the crankcase(If the seal was gone) ? Thats what im going to check next. If the cylinder was scored or damaged could that cause the problem? Link to comment Share on other sites More sharing options...
JimR Posted April 5, 2009 Share Posted April 5, 2009 Could it cut out if there was a air leak in the crankcase(If the seal was gone) ? Thats what im going to check next. If the cylinder was scored or damaged could that cause the problem? Hi, What colour does the plug come out like after doing a plug 'chop' ? This will indicate the mixture strengh at the time the engine failed. If the crankshaft seals have gone/leaking they can be checked by checking behing the mag for oil deposits (wetness), which would be the l/h seal gone or the gearbox oil level low and excessive smoke from the exhaust for the r/h gone/leaking. If the cylinder is scored you will have a rattle at idle (might be difficult to hear through the water jacket, but is the motor sounds different you may have a problem there) and if severe a lack of total performance and not a misfire at the top end. As a foot note I rode a Rieju RS2 Matrix (same engine in a Spanish chassis) on saturday and managed approx 100 kph and it ran quite sweet, with looking at the electrics on the Rieju I would be inclind to get the read outs for the CDI & pickup coil and test them HOT & COLD. Don't forget what a CDI does ...it dynamically adjusts the ign timing to suit the engine speed (rpm) so your electrics could be sending the spark to the plug at the wrong time, which in turn could cause a misfire at high rpm and other problems. Regards Jim Link to comment Share on other sites More sharing options...
tzr92 Posted April 5, 2009 Author Share Posted April 5, 2009 Hi, What colour does the plug come out like after doing a plug 'chop' ? This will indicate the mixture strengh at the time the engine failed. If the crankshaft seals have gone/leaking they can be checked by checking behing the mag for oil deposits (wetness), which would be the l/h seal gone or the gearbox oil level low and excessive smoke from the exhaust for the r/h gone/leaking. If the cylinder is scored you will have a rattle at idle (might be difficult to hear through the water jacket, but is the motor sounds different you may have a problem there) and if severe a lack of total performance and not a misfire at the top end. As a foot note I rode a Rieju RS2 Matrix (same engine in a Spanish chassis) on saturday and managed approx 100 kph and it ran quite sweet, with looking at the electrics on the Rieju I would be inclind to get the read outs for the CDI & pickup coil and test them HOT & COLD. Don't forget what a CDI does ...it dynamically adjusts the ign timing to suit the engine speed (rpm) so your electrics could be sending the spark to the plug at the wrong time, which in turn could cause a misfire at high rpm and other problems. Regards Jim The plug was light brown. I realised when I checked for oil leaks that on the right hand side at the bottom of the engine there was pure black oil. I gave the gasket a wipe form the cylinder to the bottom of the gearbox as it was black and soaked with oil. The bike hasn't been any smokier than usual only when I start it up but after a couple of minutes it clears. Could this cause the bike to cut out? Link to comment Share on other sites More sharing options...
JimR Posted April 6, 2009 Share Posted April 6, 2009 The plug was light brown. I realised when I checked for oil leaks that on the right hand side at the bottom of the engine there was pure black oil. I gave the gasket a wipe form the cylinder to the bottom of the gearbox as it was black and soaked with oil. The bike hasn't been any smokier than usual only when I start it up but after a couple of minutes it clears. Could this cause the bike to cut out? Hi, if its leaking from the gaskit this will have no bearing on the the running of the motor. Regards Jim Link to comment Share on other sites More sharing options...
tzr92 Posted April 13, 2009 Author Share Posted April 13, 2009 Hi, if its leaking from the gaskit this will have no bearing on the the running of the motor. Regards Jim I found this other forum and it looks like others have had the same problem but still no soloution. http://www.yamahaclub.com/forums/index.php?showtopic=6545 Link to comment Share on other sites More sharing options...
JimR Posted April 13, 2009 Share Posted April 13, 2009 I found this other forum and it looks like others have had the same problem but still no soloution. http://www.yamahaclub.com/forums/index.php?showtopic=6545 Hi, read the topic no one seems to have a leak from the clutch cover (as you do) so I guess that leak has no bearing on the problem you have. After ridding the Rieju again (bike with the same motor) I found that it started to 'nip' up which then gave problems with the top end of the performance until it cooled off.. then it ran ok until it got a bit warm. Is your TZR restricted or does it have the factory (minerelli) de restriction kit fitted ? Regards Jim Link to comment Share on other sites More sharing options...
tzr92 Posted April 13, 2009 Author Share Posted April 13, 2009 Hi, read the topic no one seems to have a leak from the clutch cover (as you do) so I guess that leak has no bearing on the problem you have. After ridding the Rieju again (bike with the same motor) I found that it started to 'nip' up which then gave problems with the top end of the performance until it cooled off.. then it ran ok until it got a bit warm. Is your TZR restricted or does it have the factory (minerelli) de restriction kit fitted ? Regards Jim It is derestricted as it has a different exhaust. Its a Bidalot exhaust ive never heard of it before and it was on the bike when I got it. And what is the derestriction kit and where does it go. I thought the bikes were just restricted in the exhaust. Link to comment Share on other sites More sharing options...
tzr92 Posted April 14, 2009 Author Share Posted April 14, 2009 I have a tzr 50 and my bike has recently broke down. When I take the bike up to 9000+revs it starts missing a lot which makes it drop 2 or 3 mph which makes a difference since i can only do 50mph. It does it most of the time but recently when it has started cutting out all together and the revs just drop until I stop and after that it is hard to start. the starter motor turns the engine over but it wont start. It will eventually start after 5 mins or so. Can someone help please. I have already changed the spark plug, plug lead, the coil and I have checked and cleaned out the carbuerator and connectors for the coil. I dont know what else to try. Anyone else have any ideas on what could cause my bike to cut out. You dont know how frustrating its getting lol Link to comment Share on other sites More sharing options...
tzr92 Posted April 14, 2009 Author Share Posted April 14, 2009 Hi, read the topic no one seems to have a leak from the clutch cover (as you do) so I guess that leak has no bearing on the problem you have. After ridding the Rieju again (bike with the same motor) I found that it started to 'nip' up which then gave problems with the top end of the performance until it cooled off.. then it ran ok until it got a bit warm. Is your TZR restricted or does it have the factory (minerelli) de restriction kit fitted ? Regards Jim Just a suggestion but could the reed valves be opening too much and letting in tto much air? Link to comment Share on other sites More sharing options...
JimR Posted April 15, 2009 Share Posted April 15, 2009 Just a suggestion but could the reed valves be opening too much and letting in tto much air? No chance of that, the reed valve is after the the carb & before the cylinder so there for the reed opening will have no bearing on air intake to the motor as it lets in the fuel/oil/air before the valve ... The valve is designed to stop gasses being returned to the intake/venturi, which if allowed, would make the engine run differently to how the designer imagined without the reed block installed. To date you have not responded on the other issues with the motor .. the 'black oil' you have leaking is that from the R/h cranck case cover or the centre cases ? If you have mixture being expelled from the centre case the engine is in free fall but I guess you have not looked at the the ignition side of things yet (to discount that) nor have you then followed on to the carb, it must be one of them unless the TZR50 has some odd bits that I don't know about. Regards Jim Link to comment Share on other sites More sharing options...
tzr92 Posted April 15, 2009 Author Share Posted April 15, 2009 No chance of that, the reed valve is after the the carb & before the cylinder so there for the reed opening will have no bearing on air intake to the motor as it lets in the fuel/oil/air before the valve ... The valve is designed to stop gasses being returned to the intake/venturi, which if allowed, would make the engine run differently to how the designer imagined without the reed block installed. To date you have not responded on the other issues with the motor .. the 'black oil' you have leaking is that from the R/h cranck case cover or the centre cases ? If you have mixture being expelled from the centre case the engine is in free fall but I guess you have not looked at the the ignition side of things yet (to discount that) nor have you then followed on to the carb, it must be one of them unless the TZR50 has some odd bits that I don't know about. Regards Jim Sorry I have not responded the black oil is coming from the R/h crankcase cover but I realised there was 2 stroke oil coming from the center cover and only enough to form a small drip after several runs. I have still to recieve the carb and check the ignition. I will wait and try these first. I will post back after I have tried these. Thanks for all your help. Link to comment Share on other sites More sharing options...
tzr92 Posted April 23, 2009 Author Share Posted April 23, 2009 No chance of that, the reed valve is after the the carb & before the cylinder so there for the reed opening will have no bearing on air intake to the motor as it lets in the fuel/oil/air before the valve ... The valve is designed to stop gasses being returned to the intake/venturi, which if allowed, would make the engine run differently to how the designer imagined without the reed block installed. To date you have not responded on the other issues with the motor .. the 'black oil' you have leaking is that from the R/h cranck case cover or the centre cases ? If you have mixture being expelled from the centre case the engine is in free fall but I guess you have not looked at the the ignition side of things yet (to discount that) nor have you then followed on to the carb, it must be one of them unless the TZR50 has some odd bits that I don't know about. Regards Jim I tried another carb on. The bike reacted in the same way so thats that ruled out. As for ignition, I tried the colour tune in and when it cut out it was still sparking. Could it still be an ignition problem? If so I will check the magneto. I will also be dismantling my engine at the weekend to check for air leaks. Thanks Link to comment Share on other sites More sharing options...
Moderator Airhead Posted April 23, 2009 Moderator Share Posted April 23, 2009 I tried another carb on. The bike reacted in the same way so thats that ruled out. As for ignition, I tried the colour tune in and when it cut out it was still sparking. Could it still be an ignition problem? If so I will check the magneto. I will also be dismantling my engine at the weekend to check for air leaks. Thanks Jim said earlier to check the pickup coil , check it cold, then check it when it cuts out, pickups have a habit of open circuit-ing when they are faulty and hot. That would be a good place to look. Link to comment Share on other sites More sharing options...
JimR Posted April 24, 2009 Share Posted April 24, 2009 Jim said earlier to check the pickup coil , check it cold, then check it when it cuts out, pickups have a habit of open circuit-ing when they are faulty and hot. That would be a good place to look. To Right OG, with the pick up adjusting the timming dynamically if it starts to break down the timming will end up different to how the motor was designed to run and therefore will supply a missfire due to the timming being incorrect for that motor at a given rpm.. perhaps we should go back to points to insure the timming stays within a fixed, but acceptable frame ! I have a Reiju RS2 (same motor as TZR) and to be honest after 'lifting the bonnet' I can see there could be a point that the ignition system will fail. Regards Jim Link to comment Share on other sites More sharing options...
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