Firing on right cylinder only

[DJM]

I had just this problem with my CL77 when I first built it, turned out the fuel wasn't getting through to the carbs although tap, filters and pipes were all good.

Drop the float bowl off or loosen the drain screw to make sure there is plenty of fuel in the bowl, if you loosen the drain screws leave them open for a while with the gas turned ON and run plenty of fuel through.

It sounds a bit primitive but if there isn't good flow try blowing with your mouth into the fuel tank, this should get the fuel through and you won't need to do it again unless you run out of fuel.

My brother in law had just the same problem over fifty years ago with his CB77 but I hadn't heard of it until it happened to me.

Let us know if this helps!

[fatboy98]

Hello hay i am having this same exact issue right now can not figure it out?? going to do a compression check to night but other than that im out of ideas? any help would be appreciated. thank you

[fatboy98]

ok i did compression check 100psi left side and 145 on right.this motor had a new piston put in it back in 2013 and has not been run since. i put some trans fluid in the low cylinder and and checked comp. again and it jumped up to 160psi. im not sure which side got the new piston but if it was the left side maybe the rings are not seated yet?? the left side exhaust does not get as hot as the right side.got some popping in the exhaust. Thanx for any help

[LOUD MOUSE]

I offered a PM and you don't seem to need help.
OK!. ..............lm

[Tim Allman]

ok i did compression check 100psi left side and 145 on right.this motor had a new piston put in it back in 2013 and has not been run since. i put some trans fluid in the low cylinder and and checked comp. again and it jumped up to 160psi. im not sure which side got the new piston but if it was the left side maybe the rings are not seated yet?? the left side exhaust does not get as hot as the right side.got some popping in the exhaust. Thanx for any help

What you have done is one of the usual tests to diagnose low compression. For the purpose of a compression test, pouring oil into the cylinder will seal up the rings temporarily. If there is no improvement the leak has to be elsewhere, usually the valves or head gasket. If, as in your case, the compression went from poor to very good the test indicates that the rings are not sealing well but the valves etc. are. You should do this on both sides.

It's true that compression improves as the rings and cylinders seat themselves but 100 psi is very low. I think you need to pull the top end and have a look.

[mike in idaho]

Were the valves adjusted before the compression test? A tight valve will make a big difference in compression #s. Popping in the exhaust can point to a carb sync issue. Maybe a good tune up would be in order before tearing everything apart.

[fatboy98]

I started tearing it apart i have went through through the carbs 3 times thinking it was a carb problem,i checked valve lash they was good. I
checked points and put new plugs in and nothing was making a difference. Did the comp. test and that explained it all. I do have another question for those in the know? Do i take the chain apart at the master link to get the head off or do i have to take the cams out ? If i just take the master out and keep pressure on the chain so it dont fall off crank will that work? I am sure there has to be some timing marks between the cams and crank? Thanx again for any input