enduro100CC Posted March 23, 2009 Share Posted March 23, 2009 I have a 72 yamaha LT2 enduro that I bought two weeks ago for 550. I thought that it was in great shape but I keep finding more and more things wrong with it. It had a wiring issue and the headlight would not work, also it had no battery. I fixed both of those issues. Then it had poor compression and died when it was idling. I dealt with those and now I found that my piston rings are gone. Both were broken and in the exhaust pipe. I have ordered new ones for 20.00 and a new piston for 45.00. My question is when is enough enough. How long should I go on replacing things like this and do y'all think it is likely that things are going to keep cropping up this often? Keep in mind I have had this bike a little over two weeks. I wanted a project but this is looking more and more like not just a project bike but a potential disaster. I just want to 10 miles a day on it at 35 mph to and from work, but I fear this may never happen. I have already pushed it all the way home one time, that was tons of fun. Currently it will not start and I am HOPING that the piston rings are the reason. The carb looks fantastic and when I took it apart it looked like someone had been there before me and very recently. I am not sure whether to keep putting nickles and dimes into this thing or put them in the piggy bank and hope I can get it up and running and sell it to someone with more time on their hands. Thanks for the input gentlemen! Link to comment Share on other sites More sharing options...
JimR Posted March 23, 2009 Share Posted March 23, 2009 I have a 72 yamaha LT2 enduro that I bought two weeks ago for 550. I thought that it was in great shape but I keep finding more and more things wrong with it. It had a wiring issue and the headlight would not work, also it had no battery. I fixed both of those issues. Then it had poor compression and died when it was idling. I dealt with those and now I found that my piston rings are gone. Both were broken and in the exhaust pipe. I have ordered new ones for 20.00 and a new piston for 45.00. My question is when is enough enough. How long should I go on replacing things like this and do y'all think it is likely that things are going to keep cropping up this often? Keep in mind I have had this bike a little over two weeks. I wanted a project but this is looking more and more like not just a project bike but a potential disaster. I just want to 10 miles a day on it at 35 mph to and from work, but I fear this may never happen. I have already pushed it all the way home one time, that was tons of fun. Currently it will not start and I am HOPING that the piston rings are the reason. The carb looks fantastic and when I took it apart it looked like someone had been there before me and very recently. I am not sure whether to keep putting nickles and dimes into this thing or put them in the piggy bank and hope I can get it up and running and sell it to someone with more time on their hands. Thanks for the input gentlemen! Hi There, As long as the motor didn't rattle too much and all of the rings where found in the exhaust a rebuild on this section will put the motor right. You will have to take into account that the bike has not been 'serviced' correctly for years so ontop of replacing the bits you mention it would be good to have the timming set & the exhaust system cooked & decoked. With the wiring (dependant on the state of the loom) could be restored with very little out lay or you could be on for a new loom and/or a custom rewire , It would be good to try to maintain the original wire colours just for ease of fault finding but if produce ur own loom take note of the custom wire colours you have used. Regards Jim Link to comment Share on other sites More sharing options...
enduro100CC Posted March 30, 2009 Author Share Posted March 30, 2009 Alright, so I got the cylinder machined out and it worked great!!! Kind of....So it starts in one or two kicks but I have no "get up and go." It revs up in neutral and sounds great but put it in first and start going and you are lucky to get up to twenty miles per hour. I think that the engine is not getting enough air. If I pull the choke to make it run more rich it dies. I have loosened the air screw on the carb as much as I dare. I have messed with the throttle screw, the idle screw on the top of the mixing chamber, and the throttle adjustment at the throttle handle. None of this has done almost anything. I can sense minor changes and I can manage to mess with them and get them so far off that they will not start but when I go the other way it does not seem to solve the issue, only run and start better. The bike runs really well after having the cylinder machined and getting the new piston/ rings. They fit tight so I don't know where my power is going. I know I am losing it somewhere. I went through and tightened everything on the bike in case when I reassembled the cylinder I did not tighten things enough and in the process I broke the banjo bolt that goes in the oil line at the base of the cylinder. That part is on order from Europe as no one I can find has it. So, the question is: any idea where my power is going and how to adjust to get it back?? I have done a lot of different things but the post was long enough and chances are I have tried most of the really simple things but don't hesitate to ask me anyway, maybe I forgot something. I am new to this. Thanks for the time and suggestions!!! Hi There, As long as the motor didn't rattle too much and all of the rings where found in the exhaust a rebuild on this section will put the motor right. You will have to take into account that the bike has not been 'serviced' correctly for years so ontop of replacing the bits you mention it would be good to have the timming set & the exhaust system cooked & decoked. With the wiring (dependant on the state of the loom) could be restored with very little out lay or you could be on for a new loom and/or a custom rewire , It would be good to try to maintain the original wire colours just for ease of fault finding but if produce ur own loom take note of the custom wire colours you have used. Regards Jim Link to comment Share on other sites More sharing options...
yoda Posted March 30, 2009 Share Posted March 30, 2009 It needs running in. The loss of power when accelerating is probably the float height of the carb. That assumes that the timing is spot on. You also need to check that the fuel tank and petcock are clean. Link to comment Share on other sites More sharing options...
enduro100CC Posted March 30, 2009 Author Share Posted March 30, 2009 Fuel tank and petcock are clean. The inside of the tank is pristine and I cleaned out the petcock and then let it dry out and checked it again. I have a float chamber gasket on order as well so when I open it up I will check the float height in the chamber. How do I check/ adjust the timing. The service manual was a bit vague in its instruction and so I am not sure that I followed what it was telling me to do. Thanks!!! It needs running in. The loss of power when accelerating is probably the float height of the carb. That assumes that the timing is spot on. You also need to check that the fuel tank and petcock are clean. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted March 30, 2009 Moderator Share Posted March 30, 2009 You say it dies when you apply the choke, this indicates that it is not running lean, however it might be running rich. Two things that can cause that are, clogged air filter,( take out the filter and try it without.) or float level in carb too high..to check if this is so switch off the petcock as you are riding, if the bike suddenly accelerates before running out of fuel in the carb then the fuel level is set too high. Link to comment Share on other sites More sharing options...
enduro100CC Posted March 30, 2009 Author Share Posted March 30, 2009 I just put in a brand new air filter but it did not have an air filter in it before so the new one might seem like a clogged one by comparison. I know it is running rich because the spark plugs are covered in a dark residue after very little riding and someone told me that indicated that it was running rich. I will try it without the air filter and do the check for the float level once I get the parts I am waiting for in. I had to order a flange bolt for the auto lube system. It sounds like I can bet the float is set to high though. Thanks a bunch! I spent hours messing with different things yesterday trying to figure out what setting was not correct and made no progress. The float makes a lot of sense though. I am not sure exactly what the setting is but I remember seeing it in the service manual on my workbench. Thanks again!!!!!!! Nick Link to comment Share on other sites More sharing options...
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