Honda Twins banner

1 - 7 of 7 Posts

·
Registered
Joined
·
46 Posts
Discussion Starter · #1 · (Edited)
In the space of a week, my bike went from the best it's ever ran to not running at all on the right cylinder without choke. The only way I'm verifying this is that the right side header is only warm, not scald your skin clean off hot. If anybody has a better way to verify if a cylinder is firing, please let me know.

ANYHOW, I think the issue might be due to a sudden and sever air leak. When I rev the bike up I can hear a distinct "puff puff" noise coming from the right hand cylinder. I thought I might be confusing this sound with backfiring through the carburetor, so I recorded it and posted it on youtube for your viewing pleasure.


I haven't gotten a chance to test for an air leak by spraying starter fluid around the carburetor boot and air filter collar, but I'll be doing that tonight and reporting back.

In the meantime, what do you smart folks think that sound might be?
 

·
Registered
Joined
·
543 Posts
that carb is not adjusted properly. go back to square one and re adjust cable/slide, idle speed and mixture screw. whether or not this is from an air leak or not, you'll find out when you test for that.
 

·
Registered
Joined
·
46 Posts
Discussion Starter · #3 ·
Normally I'd say you're 100% right, only I adjusted the carbs when I did the timing last week and had the bike running fantastically well. Starting cold on one kick, pulling hard at every RPM ¯\_(ツ)_/¯
 

·
Registered
Joined
·
543 Posts
maybe check fuel flow? one outlet could be clogged. my 350 had a prob with the stock petcock; sometimes the fuel would stop flowing from one outlet. so much so that I had to switch to a single outlet petcock and T the line. even a new dual petcock wouldn't work. twas very strange.
 

·
Premium Member
Joined
·
2,149 Posts
Re-check carb sync. Sounds like ferrule may have been sitting on top of adjuster instead of inside it or nipple wasn't properly seated inside carb slide?
 

·
Registered
Joined
·
46 Posts
Discussion Starter · #6 ·
Okay there were two problems.

One: the bike barely had enough fuel to run with the pepcock set to on instead of reserve, and once I put some more gas in it, things were better. That was just dumb.

Two: There was indeed a carb sync issue! The throttle cable surround had come out of the brass adjuster screw at the top of the carb, goofing up the sync of that carb. Until the end of the summer I think it'll be fine as long as I check to make sure the cable is seated properly in the adjuster. Once the unpleasant months start I'll fix it.

Thanks for the help everybody!
 

·
Premium Member
Joined
·
2,149 Posts
Okay there were two problems.



Two: There was indeed a carb sync issue! The throttle cable surround had come out of the brass adjuster screw at the top of the carb, goofing up the sync of that carb. Until the end of the summer I think it'll be fine as long as I check to make sure the cable is seated properly in the adjuster. Once the unpleasant months start I'll fix it.

Thanks for the help everybody!
In my experience, it's a pretty common problem with Mikuni's with the short rubber cap on cable
 
1 - 7 of 7 Posts
Top