Cafe racer exhaust

[ital916]

Hey guys

Work starts soon on turning my srv250 into a cafe racer. Just a question about exhaust mufflers. I was looking at the mufflers available on the market today and they are quite large, so anybody happen to know of any small, classic style mufflers that will give a very nice sound, whilst maintaining that classic bike style? Straight pipes I hear are complicated and need to be calculated correctly or will harm performance. How will the change in back pressure affect performance? The srv's run the same engine as the yammy virago 250, and I know for a fact they can sound very very nice if done properly. Are dump/shotgun pipes legal, as they sound awesome and look quite nice with their straight from the engine short look. Sorry for the noob questions, I've never customised a bike before.

Drider

[Ixion]

Dunstall short megas. Can't be anything else.

[ital916]

guessing that the brand and model name? Lol I will go research them now. Does the bike need to be retuned once the new muffler is installed?

[ital916]

Is there a company webpage I can't seem to find one?

[AllanB]

first one is a Supertrapp - removable disks so you can tune it and the sound, alloy with a weld-on tab.
from www.denniskirk.com US$180 plus shipping (very good to deal with).

Second also Supertrapp - pretty www.cyclestuffusa.com (never used them).

Third is a long 700 mm Dunstall replica - available in NZ and on trademe too - shop around for these - about $110 each is the max you should pay in NZ. Also available in a short form - 400 mm I think.
I ran the long ones on my old 750 twin - loud - I ended up making a db killer insert.
The short ones are very very loud. The good thing is that you can piss about with the internals as they are removable. These are Asian knock-offs, clean looking but fairly light weight materials (the original packing is I think a collection of old men's belly-button fluff - and blew away in 500kms).
Make sure you get the ones with the removable core if you want to be able to messy around - there is a set that are fully welded that are similar.

[pete376403]

Paul Dunstall was an english custom bike builder of the 60s and 70s. His design for mufflers "Dunstall decibels" was a classic, slow taper megaphone witha short reverse cone.
http://cgi.ebay.com/ebaymotors/Repli...ayphotohosting
Initially Dunstall made parts for the British bikes, but later made Honda accessories as well.
A classic cafe racer look for your yamaha would be to try and make it look like an egli Vincent
http://www.godet-motorcycles.com/egli/egli.htm (this will be my Powerball winner bike)

[avgas]

For me supertrapps are fantastic and my fav's.
I like Dunstalls on say a Norton but to me they look rude on everything else.
Talk to custom chambers - as i have never seen a bad piece of work ride out of that shop.

[xwhatsit]

You can get the short reverse-cone Dunstall replicas (waffle-baffles in the exit) for about $100 on Tardme, or about the same if you order them through bike shops. EMGO produce them. Keep the stock headers, put a couple of shorty megas on the back. Debaffle them first, the EMGO ones are quite easy, you just have to break off one or two tack-welds at the entry end, then the baffles should slide out easily.

SRV250s have marvellous looking headers, especially the right-hand side. A pity it's not a 2-into-1, the bikes are slightly porky (already 144kg dry) for ~26hp, so there's already a few kg you could save by doing that.

[Ixion]

Well, it could very easily be made 2 into 1. The virago (can't swear the SRV is the same), the apparent rear header is a fake. The real header is unchromed and runs behind the engine right down to about the real header form the front cylinder

[Jacko2]

Dushy, your bike is 2 into 1 already and already has and after market exhaust

[xwhatsit]

Dushy, your bike is 2 into 1 already and already has and after market exhaust

Photos!

Well just pull off the end-can and chuck on one shorty mega.

[Jacko2]

Photos!

Well just pull off the end-can and chuck on one shorty mega.

Go to Dushys unveiling, hehe

[ital916]

Thanks jacko, yeah i'm not changing the whole system just the muffler/silencer *haha yeah right, my one won't silence anything* and repainting the heat shield but will re silverise the headers or matt black them. Just thinking bout the paintjob, i'm basically gonna go for a satin black with some other details in red, will be very very awesome. A few custom mods shall be ordered in from ebay. What diameter are the bars on the srv? Hey ixion, my one is the renaissance version of the srv. There were two versions that were produced. Just fairings were very nice people, they quoted 500 for a rear cowl to cover the pillion seat like a proper cafe to be made. Thats way too expensive but the srv already looks very cafe so that is alright by me, i'll leave her stock. Can't wait to start tinkering. First thing though we need to get her running like a beaut.

[Devil]

My vote goes to custom chambers.

Saw/heard a Bonneville T100 with CC pipes on it the other day. It sounded and looked perfect. Not too loud either.

[FilthyLuka]

Hey mate, Satin Black? You making a rat or a cafe racer? In my oppinion, a cross between the two would be cool. Rat Cafe racer... Or would that be west auckland pub racer, who knows

yours bars will be 7/8" in diameter. However, measure your fork legs than get appropriate clip ons from either www.bikestore.co.nz (woodcraft) or from motomail (tomaselli), they are both around the same price ($250+/-)

Also, if you put a free-flow pipe on it wouldn't hurt to jet the carbs. I can give you the number of a dude out west who is great with carbs and not to expensive either, once you have done all the intake/exhaust mods, send it to him and he can balance/tune your carbs. PM me if you wan't his number (the guy is out west BTW)