Exhaust leak at the muffler/header joint

[mike_d]

Hi Guys,

I've now got my '77 xs running great. I picked it up a couple weeks ago. It has vm34 carbs and pamco electric ignition. It took a little messing around but it now starts right up, idles great and pulls well at all throttle openings. Though today I noticed that there was a leak on the header pipe where it meets the muffler -- on both pipes. The right side appears to be a hole, the left pipe just appears to be a bad seal. Is this cause for concern? I've owned british singles where this would be an issue and I would sort it out right away but the XS seems to be running great. I'm not looking to get new pipes -- I bought this XS as a temporary bike while rebuilding my main bike (or maybe I fall in love with the XS and have two bikes!) -- but I would like to tackle the issue should it be a problem.

Thanks for your help and insight.

Mike

 

[NONclow]

The right side appears to be a hole, the left pipe just appears to be a bad seal.

The stock pipes are double walled. The hole you speak of is to allow condensation to escape. The right side likely has a cracked inner pipe. I found this issue once by taking the muff mount loose (not at the head) and VERY lightly wiggle the pipe up and down side to side. A broken/cracked one will move more than a good one. The bad left "seal" could be tightened and checked the same way, but the seal could be toast anyway

 

[weekendrider]

Does it have original mufflers with the castle nuts?
Or a clamp?

 

[XSLeo]

If stock the 77 had a slip on muffler.
The muffler end of the head pipe the inner and outer pipes tapered together to make the pipes seal. The muffler slipped over this tapered end of the outer pipe. The nut tightened and squeezed the gasket to seal onto the head pipe.
If some one swapped the stock carbs to VM34's I doubt they left the mufflers stock.
Pics will help.
Leo