Home made Exhaust for 2001 650

Hey all,

I have, unfortunately, been off the bike for the last year solid, technically I still am as I havent been out on it yet.

Anyway, during the rest up period I decided that I would polish the aluminium exhaust. So I took it off and brang it to work.

We have an engineering work shop there and while there I had an epiphany.
Replace the aluminium skin with some 2" Sched5 316L SS .

I cut off the aluminium skin and found that the exhaust was basically an outer aluminium casing, an inner perforated pipe, some glass fibre (exact same stuff as is in your attic) and two Stainless Steel end caps (one for the connection side and one for the exhaust gas outlet)

A long story short, I got some 316L SS pipe and welded the whole thing up. The glass fibre had been totally burned up over the years so I replaced it with some new stuff. The original was riveted togther, but it is now completely welded.

The welds are ground and polished and the entire thing now has a pharmaceutical grade finish due to amount of polishing it has had. >0.45Ra if if your in the know.

Anyway, this thing is never gonna fade or corrode. It looks absolutely great.

I got the bike started today and the noise as it ticks over sounds a little lower as I recall, which I like. When you rev it it sounds great, but when you release the throttle it sounds amazing. Will have to try leave the house in the mornings without going down the revs.

Anyway, If anybodies interested I'll pop up some photo's in the coming days.

Just chuffed with my tidy job and had to tell somebody who might actually be half impressed, the wife certainly wasnt as happy as I was

[jambo]

Originally Posted by shortz

had to tell somebody who might actually be half impressed, the wife certainly wasnt as happy as I was

I'm impressed, the system you replaced certainly isn't the standard exhaust, so the question is, what have you modified?

The standard cans are all steel, and have quite complex internals to keep the noise down.

Jambo

[CheGuevara]

Originally Posted by shortz

The glass fibre had been totally burned up over the years so I replaced it with some new stuff. The original was riveted togther, but it is now completely welded.

So you have to cut it open again next time you want to replace the packing? I'd be doing that every year (a few times/year on my old KTM supermoto) -which is I suspect why they use rivets in the first place.

I'd like to see the pic's...

Originally Posted by RichT

I'd like to see the pic's...

+1
do you take orders?

[yorkie_chris]

Don't weld them up, you have no way to repack it. Maybe weld one end and bolt the other so it is neater.

[wattyfred89]

pictures?

I'm away from home at the minute so you will have to wait till the weekend.

The exhaust wasnt standard as you rightly pointed out Jambo. I think it was a G-Force, cant really remember, it was on the bike when I got it.

Anyway, its welded shut. Not to bothered if I have to cut it to replace the packing as this will be a few years down the line and it isnt a major job to get it re-welded, as I work with welders.

I was gonna rivet it back together, but once you pop the originals, replacements never go back in properly. I tried it but it looked sh*t.
This is why I welded it and I think you will agree, the fully welded looks great.
All welds are removed and polished so you cant see where either bit begins or ends. It just looks like one piece.

I'll defo get pics up for ya's to have a look, I'll even accept criticism graciously!

Talk then ppl!

John

[yorkie_chris]

Oh yeah it definitely looks spot on when you can weld stainless well and remove any sign of the weld.

But IME they need doing every 10k miles or preferably less.

You dont just weld around the surface of the two pieces and then remove it.

Both pieces have there edges ground back so that essentially you are purging the piece. So its a single run fillet weld that joins the two pieces.
The weld is solid but is raised. This is what you would see on the frame of a bike near the headstock. Its an "as Laid" weld without a ground finish, although it may be polished.

Mine is both ground and polished and is crack and crevice free. Im working with welders that usually work on pharmaceutical grade, pressure rated equipement (PED directive stuff). The finish is >0.45Ra which is pharma grade which makes it very easy to clean. Its almost mirror finish. Not too far off as you will see.