heritage
XS400 Member
Hello and thanks to everyone for the help in the past helping me out.
I have a question once again
I believe I have a good handle how to clean and how to ensure there are no air leaks at the carb. But I am not sure where to go when a bike starts great, idles well, choke will responded , throttle is responsive but after running 5 mins one carburetor will back fire through the exhaust and carburetor. Once it starts it won't stop back firing through the exhaust and carburetor no matter how I adjust the mixture screw. After my last adjustment the carb giving me trouble now wont even fire and heat up the exhaust pipe on;ly back fire.
1) I am now thinking it now could be the intake & exhaust valves not adjusted properly - does anyone have a detail method how to confirm / set the valves. I have heard:: Intake .003 - .002 and Exhaust .006 - .004
2) I have pulled the carb apart many times - cleaning the choke circuit, idle circuit and main circuit ,
Any suggestions?
3) idle mixture screw - 21/5" turns out?
Any other suggestion to try?
I have a question once again
I believe I have a good handle how to clean and how to ensure there are no air leaks at the carb. But I am not sure where to go when a bike starts great, idles well, choke will responded , throttle is responsive but after running 5 mins one carburetor will back fire through the exhaust and carburetor. Once it starts it won't stop back firing through the exhaust and carburetor no matter how I adjust the mixture screw. After my last adjustment the carb giving me trouble now wont even fire and heat up the exhaust pipe on;ly back fire.
1) I am now thinking it now could be the intake & exhaust valves not adjusted properly - does anyone have a detail method how to confirm / set the valves. I have heard:: Intake .003 - .002 and Exhaust .006 - .004
2) I have pulled the carb apart many times - cleaning the choke circuit, idle circuit and main circuit ,
Any suggestions?
3) idle mixture screw - 21/5" turns out?
Any other suggestion to try?
