Dave07 Posted May 22, 2009 Share Posted May 22, 2009 I have a 81 yamaha xs 400 . it runs great but one thing i noticed is when I first start it to let it warm up the exhaust will make a popping noise on the right side which comes and go's. But after it warms up I don't notice it as much. The left side exhaust dont pop. what should I check for? Link to comment Share on other sites More sharing options...
JimR Posted May 22, 2009 Share Posted May 22, 2009 I have a 81 yamaha xs 400 . it runs great but one thing i noticed is when I first start it to let it warm up the exhaust will make a popping noise on the right side which comes and go's. But after it warms up I don't notice it as much. The left side exhaust dont pop. what should I check for? Hi Dave, I guess your bike is misfiring when cold. Perhaps you should adjust the mix screws & balance the carbs .... TBH while your at it I would check the tappits, Timing & Dwell and along with that put some new plugs in & this should fix the problem. Regards Jim Link to comment Share on other sites More sharing options...
Dave07 Posted May 22, 2009 Author Share Posted May 22, 2009 Hi Dave, I guess your bike is misfiring when cold. Perhaps you should adjust the mix screws & balance the carbs .... TBH while your at it I would check the tappits, Timing & Dwell and along with that put some new plugs in & this should fix the problem. Regards Jim This is my first bike I know it has new plugs in it . How do I balance the carb.? I don't know a much about bikes. What are tappits? Is the mix screws on the carb.? Thanks again Link to comment Share on other sites More sharing options...
JimR Posted May 22, 2009 Share Posted May 22, 2009 This is my first bike I know it has new plugs in it . How do I balance the carb.? I don't know a much about bikes. What are tappets? Is the mix screws on the carb.? Thanks again Hi Dave, Tappets (translate from English) = Check the Valve Clearances .MM intake .MM exhaust To Balance the Carbs you will need vacuum gauges The Mixture screws would be adjusted in conjunction with the balance operation. As you are new to mechanics it would be good to track down a workshop manual to familiarize your self with the bike and some mechanical terms etc etc, but if you want a talk thro let me now Regards Jim Link to comment Share on other sites More sharing options...
Moderator drewpy Posted May 22, 2009 Moderator Share Posted May 22, 2009 Hi Dave, Tappets (translate from English) = Check the Valve Clearances .MM intake .MM exhaust To Balance the Carbs you will need vacuum gauges The Mixture screws would be adjusted in conjunction with the balance operation. As you are new to mechanics it would be good to track down a workshop manual to familiarize your self with the bike and some mechanical terms etc etc, but if you want a talk thro let me now Regards Jim I just weighed each carb and balanced them by filing some alloy off one side!! Link to comment Share on other sites More sharing options...
Dave07 Posted May 22, 2009 Author Share Posted May 22, 2009 I just weighed each carb and balanced them by filing some alloy off one side!! I went to start the bike now it don't make the popping sound anymore. But one thing I noticed was after it sat for a bit i noticed gas coming out of the one side of the carb. I was told that the float was stuck open . What would be the best way to clean it . I was told to get some carb. cleaner and spray into it. What would you suggest? Link to comment Share on other sites More sharing options...
Moderator drewpy Posted May 22, 2009 Moderator Share Posted May 22, 2009 I went to start the bike now it don't make the popping sound anymore. But one thing I noticed was after it sat for a bit i noticed gas coming out of the one side of the carb. I was told that the float was stuck open . What would be the best way to clean it . I was told to get some carb. cleaner and spray into it. What would you suggest? its usually the little needle valve that goes you canget them from ebay or sirrus consolidated. easy enough to do, but you need to take the carbs off the bike first. Link to comment Share on other sites More sharing options...
JimR Posted May 22, 2009 Share Posted May 22, 2009 I just weighed each carb and balanced them by filing some alloy off one side!! Hi Drewps how droll Regards Jim Link to comment Share on other sites More sharing options...
Moderator drewpy Posted May 22, 2009 Moderator Share Posted May 22, 2009 Hi Drewps how droll Regards Jim Link to comment Share on other sites More sharing options...
JimR Posted May 23, 2009 Share Posted May 23, 2009 Link to comment Share on other sites More sharing options...
Dave07 Posted May 23, 2009 Author Share Posted May 23, 2009 its usually the little needle valve that goes you canget them from ebay or sirrus consolidated. easy enough to do, but you need to take the carbs off the bike first. Thank you for everyones help!!!!!!!!! Link to comment Share on other sites More sharing options...
JimR Posted May 23, 2009 Share Posted May 23, 2009 Thank you for everyones help!!!!!!!!! Hi Dave, just looked back thro the pervious posts and for some reasaon the site lift MM rather than 0.1 mm and 0.15 mm Regards Jim Link to comment Share on other sites More sharing options...
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