DIY muffler

[GSVR]

On the topic of exhausts... How do they round the tips on exhaust pipes?

http://www.neptunemufflers.co.nz/textureb.jpg

(Not even sure what you call it when you do that to a tube? Or what tool you use to do it? (Have tried Google with no luck...))

Could be a variation on a tool plumbers use call a "Crox Tool" Basically it has ball bearings that expand out. You turn the tool and the bearings expand the metal.

Or could be rolled between two formers.

Better rolled can end is on Yoshimura exhausts as they are rolled right over to form a perfect bead.

[tommorth]

you can buy carbon fibre tube in varying sizes nt sure on how much $ or if it would be thick enough save a bit of stuffing around though just cut to length and put end caps on

[blade1000]

warren of virgin mufflers can weld titanium

[imdying]

you can buy carbon fibre tube in varying sizes nt sure on how much $ or if it would be thick enough save a bit of stuffing around though just cut to length and put end caps on

Not that is thick enough or can take the heat That's the NZ places at least, don't know about overseas... probably just make it myself anyway now.

warren of virgin mufflers can weld titanium

Mmmm, haven't been tempted to try any more muffler places... Neptune wasn't interested in helping me, and that sort of tempered my enthusiasm. Had trouble now and then with tradesman that can talk the talk, but not walk the walk, so now I try to make what I can myself. However, if you know this guy, ask him if this is up his alley, and a rough ballpark on dollars

It's 440mm long, 200mm wide, 100mm tall.

[Pancakes]

Still after comments...

Has anyone built there own carbon fibre muffler? I'm thinking a combination of stainless and carbon might be ok.

If carbon isn't strong enough, I guess I can just add more layers?

Has anyone ever tried to vac bag a tube? I've a few ideas on how that might be accomplished, but would be interested in talking to those that have done it.

Anyone got an opinion on how many layers to use? 3? 5? Can you vac bag 5 something 5 layers thick? Or do you have to do each individually? Can you make the tube with one layer, and then add more after the first has cured? Or do all the layers have to be 'wet' at once to ensure adhesion between them?

Anyone got an opinion on what sort of minimum corner radius you would have to use for 3-5 layers?

What about sealing the metal ends to the carbon tube? Just use maniseal at the join, then rivet it up good?

What about what sort of rivets to use?

Packing? Where would I get glass pack suitable for one? Or could I used fibreglass chopped strand? Or get some fibreglass cloth and 'loosen it up' (tear it apart some) before packing the muffler?

I played around with one and it looses a little bit of bottom end and gains a ton of top which is pretty predictable for a freeer flowing pipe on a little twin. Just haven't done enough testing to be happy to run it on the bike all the time, not sure about the mixture etc and cos I mainly commute bottom end is nice. I'll go to the shed and take some pics of it in a mo'. It's not pretty cos its just a dummy right now. Carbon can be had at reasonable prices from Kilwell in Rotorua, almost all of the carbon in NZ comes from there (rolled) or pre-preg and the blank sheets which are better for home use cos you can lay it up then epoxy from something composites in William Pickering Dr, Albany. Mine is just fibreglass and takes shitloads of heat, You can order glass with one layer of carbon over from Kilwell, cheap, light and looks carbon. I tried the proper stainless wool packing but needed more muffling and used some pinkbatts. Lighter, goes white after being hot the first time. Smells funny and smokes as it comes up to temp the first time and I wouldn't smell it tho I don't know exactly what it's giving off. Probably smoldering spiders. Wanted to put it under the bike Buell style but no room so as it's high and behind the rear axle I wanted a lighter option. it is straight thru 2" perf pipe so friggen loud and makes the Hyo sound like a big grunter at low revs then screams like a 4 stroke MX bike up high.

[Pancakes]

Oh yeah, this is an off cut of a mast, got it free.

[imdying]

Yikes! Mill that puppy out and make a muffler

[Pancakes]

Those holes you can see on the end match up to a Hyo exhaust flange. It's a bit shorter than a std Hyo' one, about 310mm. Is 90mm OD, has been on the bike for some commutes and a few rides around the place so has been up to temp enough to see if it'll die or not. Is 8mm wall so plenty light but should take a fair whack. the wrap and end caps would make more of a difference (I guess) than the outright wall thickness. I got the end plates cut out of standard rolled steel cos it's just the tester, tacked a pipe on the inside that fits snug, used some exhaust silicone on it and the caps are held together just by the 2" perf tube.




(down there, what I did this morning)

edit, never looks as ggod when your mate takes the pic late a, good riding tho and there's a restaurant in Unitech with cold beers!