Exhaust Question

[Downeaster]

I've seen the thread on adapting aftermarket mufflers to the stock double-walled headpipes and plan to do just that.

The picture shows my stock headpipes with the mufflers cut off. This leaves me with questions:

1. Should I cut the outer pipe further up towards the head? I'd prefer not to leave that fuggly boss where the outer pipe ends.

2. If I can't/shouldn't cut the pipe higher up to get rid of that, what's the suggested technique for covering it?

3. Should I cut the inner pipe shorter? It runs up inside the new mufflers just fine. I can a) leave it as is as long as it clears the baffles in the muffler; b) cut just enough off to clear the baffles if there's a problem, or; c) cut most of it off leaving enough to clamp the adapter and new mufflers to.

 

[nj1639]

I have a pair of headpipes that the muffler was sugically removed just like that. I had thought about grinding that boss down to the diameter of the outer head pipe and then go from there as to fitment of the muffler/trimming the internal pipe. I believe others have trimmed just to the engine side of that boss and used the adapter.....though I like my idea better IF I ever want to run the curved, stock headers again.

 

[Mharrington]

I am adapting some beautifull Harley Davidson take off mufflers to my XS650. I cut off my oem mufflers and leftthe largest diameter section of pipe in its entire length. (It can be trimmed shorter, if needed, later!) My Harley mufflers are too big on the intake end and do not fit snug over the XS pipe. I used a section of the Harley exhaust pipe(I bought an entire take of system for $20!) to use as an adapter taking up the difference. The Harley muflers slide all the way on completely covering the large diameter section at the end of the XS pipes. The Harley system came with some fantastic clamps which look very nice. I completely wrapped my shiny new to me mufflers in masking tape too. This protected the chrome during all the handling of mock up. I hope I provided some help.

 

[lsc86]

Interesting idea, just curious if you'll have any sound at all. HD mufflers are usually extremely quiet and restrictive.

 

[Mharrington]

I got the idea after cycle season was done- I wish i knw how they sound but it will wait to spring. I THINK- it will sound good. The oem mufflers were rotted out and rattling. As far as restrictive- I seriously doubt it. I have my gripes about Harleys and the many arrogant ignorant owners out there but the mufflers were INEXPENSIVE, are thick steel with great chrome plating and the smallest Harley is an 883. I dont know the displacement of bike my Harley mufflers came from but on a 650 they should be fine. (Other people are happy with there Harley mufflers on their bikes. I picked up another set I plan to try on my XS1100. The exhaust on my 1100 has been sandblasted and painted dull black (Chrome was shot) I would like more Chrome on my 1100 and the second set of mufflers I bought appear brand new. On the 1100 I will try to build in a crossover as the factory had one- On the 650 there will be no crossover. For the 650 I paid $20 for and entire exhaust system- (beefy clamps and heatshields are an added bonus.) The heatshields will cover the stamped in HD legalities. The mufflers for the 1100 I bought of ebay and paid $35 to my door. They appear brand new and also have heatshields. If I notice any diminishing returns on the 1100 I will simply put the oem mufflers back on. You guys realize HD oem mufflers are very well built with show quality chrome. I hope they are quiet as thats how I like my bikes!

 

[AndreXS]

Town by-law has me looking for new pipes for my 81xs650 bobber. The 2000 rpm db level ought not to exceed 90db which I guess is around the stock level? The stock pipes seem to quiet for my liking so I am considering Mikes Commando for specials pipes which are advertised as quiet but louder than stock. My worry is are they to loud, Mikes doesn't rate his pipes by sound level? I can be seen with my bike on facebook, Andre Cokic.

 

[XSLeo]

Downeaster, Those two holes you see in the side of the pipe. Cut it right between those two holes. This will leave you with The inner and outer pipes sealed together. No leaking between the pipes. This area is 1 11/16 inch OD. The set of 81 Special pipes , or whats left of them, Are that size right at those holes.
Most 1 3/4 inch mufflers come with a set of adapters, These adapter sets are three pieces of steel pipe with a slot cut in one side. The set I have the largest adapter measures 1 3/4 OD with 1 11/16 ID. This means with this adapter on your pipe where I suggest cutting and A 1 3/4 inch muffler will be a snug slip fit.
For a good clamp go to most any Harley dealer and get thier muffler clamps. Best on the market. None stronger and none seal better. To bad they only come in 1 3/4 inch size.
There may be a section just ahead of the muffler that isn't pretty chrome plated.
In one of the threads where parts store tail pipe adapters are used to get the muffler seald to the inner pipe, they show using a piece of plumbing chrome plated brass drian pipe as a shield to cover the not so good looking.
Instead of the muffler adapter you might be able to cut a piece of the drain pipe long enough to reach from the end of the header forward to cover the ugly and use as the adapter. Cut a slit in one side of the drain pipe Slip it on the header so one end is flush with the end, the muffler slips on over the drain pipe and whhen the clamp is tight it holds the drain pipe in place. Have the slit inside and down a bit. and you won't see it.
Leo