exhaust question... flanges?

[Reverend]

I installed my V&H StraightShot HS's on the bike a while back, and I haven't had much of a chance to ride lately.

I noticed upon the initial test-ride that I was getting some popping on decel, so I assume I have to re-jet. No biggie.

There was one concern during installation. When removing the stock exhaust, I noticed that there was a removable ring flange holding the stock exhaust flange onto the head. The V&H didn't have this -- just a straight pipe, and a flange, but nothing to keep the flange on the pipe. I was thinking this wouldn't seal well.

I tried to put the stock O-flange on there to keep the head flange on, but the stocker was too small for the newer bigger pipes. I installed anyway, and I can feel the air pumping out the side of the exh flange with each revolution, so I know there's an exhaust leak. I can't hear it, but it could be the reason I'm getting as much decel popping as I am.

Any suggestions?

[AirportFF]

A similar question was raised the other day. Check here


http://www.shadowriders.net/forums/showthread.php?t=672

You might find an answer there

[Reverend]

Nope, different issue. the pipes are actually kind of loose. I tighetened down the head pipe bolts at the flange to about 10 ft-lbs or so, and the flanges just sorta flopped around like that, so I tightened them down to the head, and the pipe isn't going anywhere now, but there is a small leak. I'm thinking about using a high-temp RTV gasket sealer to assist the seal, and the crush gaskets I used were new, so I know that isn't it.

I'll take a picture of what I'm talking about tonight when I get home.

[AirportFF]

So you're saying that the inside diameter of the new pipe is larger than the outside diameter of the old one? Also if the leak is at the flange I would replace those gaskets as well. It doesn't take too much to screw them up.
When i did the Cobras on my bike the upper slip on for each side was a touch bigger, but too small for the gasket. I contacted Cobra and they said that it was designed that way and to put some high temp silicone there and tighten the hell out of the clamp. Granted the clamps that they provided are massive stainless units and could take the torque. It was similar to doing a car exhaust where you have metal to metal contact and a clamp.

Try giving V & H a shout, I'm sure that they will have the answer for you. At least that way you're getting it right from the source.

[Reverend]

Try giving V & H a shout, I'm sure that they will have the answer for you. At least that way you're getting it right from the source.


i think that's gonna be my best course of action right now. Hopefully they'll either tell me what needs to be done, or send me a part that'll fix it.

[AirportFF]

Keep us posted. I'm sure you're not the first with the problem. :happy:

[Reverend]

well I know I definintely won't be the last.

[Reverend]

ok just got off the phone with Bruce @ V&H. Nice guy, btw...

He said that if the flange is loose on the acorn nut for the exhaust port studs, use a lock washer in between, or you can actually tighten the nut so that the end of the stud breaks through the top of the nut, and tighten it that way. If there is an exhaust leak, he recommends some high temp RTV..... just as I was originally thinking.

[navillustoo]

Rev,
Different pipes, different bike, but my V&H pipes came with spacers that go between flange and acorn nut to take up the extra stud length. So Bruce's advice to use a washers would seem to be OK! That flange has GOT to be tight to seal the head pipe up against the copper gasket or you will have a leak!

Brian