twin exhausts vs one

[the pits]

I'm curious as to why Kawasaki and Yamaha's 1000's use two understeat exhausts and Honda use just one. I always thought that a single exit pipe was best ie like the Kwak ZX12 had and the Busa and Blackbird didn't. Until recently all race reps had a single exit. I know the ducati 916 created the twin underseat exhaust look but it only had 2 cylinders so I guess it didn't matter. With cars there's something about 4 to 2 to 1 being best for high rpm power. 4 to 2 to 1 to 2 seems sub optimal to me.

What I'm trying to get at is, wouldn't a single pipe at the rear of the new ZX10 and R1 be the optimum? And has anyone done it? However I know they race with twin so maybe it's not. That and the new 2007 R1 also has twin tail pipes. Over to you lot.

[ssray]

The main reason for two exhausts is that they can asborb sound better,on some 600ish singles they put two silencers on them as you would get one 600cc bang(controlled burn) where as with a 600 four you will get 4x 150cc size bangs and now with euro4 upon us it means the package can be a bit smaller rather than a big single one.
Ray

[FROSTYR1]

Putting aside the technical reasons to have twin exhausts or one...I just think twin pipes just look better IMHO

My first bike with twin stacked exhausts was my RGV250P and i still think that look hasnt been beaten since. Ive never been a fan of underseat exhausts why hide them away so you cant see them??

[black-k1]

FROSTYR1 said:

Putting aside the technical reasons to have twin exhausts or one...I just think twin pipes just look better IMHO

My first bike with twin stacked exhausts was my RGV250P and i still think that look hasnt been beaten since. Ive never been a fan of underseat exhausts why hide them away so you cant see them??

Have to agree with the ‘two look better than one’ statement although I prefer to see them symmetrical about the middle of the bike. High levels or under seat being the best option in my opinion.

[the pits]

I don't mind the looks and I accept the twin pipe theory for noise reduction but that still doesn't explain why kawasaki went from 1 to 2 for the new Zx10 and like yamaha continue to use two underseat pipes on their BSB and WSB racers. Surely noise comes second to bhp in racing? 2 must be heavier as well surely?

[Steve_T]

4 into 1 for top end power, 4 into 2 into 1 for more mid range torque typically and less top end power.

Steve.

[the pits]

Sorry that's what I meant originally.

So what does 4 to 2 to 1 to 2 mean then?

[Steve_T]

4 -> 2 -> 1 headers, then branching back out into two cans.

[randlemarcus]

If its looks alone you are after, I give you the sexiest bottom in the whole wide world:


The 2006 brochure has a black one in darkness, with the end cans glowing, but thats actual porn....

[dvs636]

the pits said:

I don't mind the looks and I accept the twin pipe theory for noise reduction but that still doesn't explain why kawasaki went from 1 to 2 for the new Zx10 and like yamaha continue to use two underseat pipes on their BSB and WSB racers. Surely noise comes second to bhp in racing? 2 must be heavier as well surely?

I'm sure i read somewhere, only one of the cans is used on the WSB yamaha. The Other is a dummy can.

[the pits]

I agree the MV's rear end makes this discussion redundant!

However, I too heard the race R1s use a dummy can which is just unnecessary weight and more than a bit daft but I have defo seen flames coming out of both exhausts on the Kwakers. Or was that just Chris Walker's farts being ignited?

[dvs636]

[quote=the pits]

However, I too heard the race R1s use a dummy can which is just unnecessary weightquote]

isn't it to do with WSB requlations, got to have the same siluatte (My spelling is trash!!!!) as the road bike.

[chilli]

randlemarcus said:

If its looks alone you are after, I give you the sexiest bottom in the whole wide world:


The 2006 brochure has a black one in darkness, with the end cans glowing, but thats actual porn....

Gorgeous........I think I've just........yep, "taxi"! Won't be long before IT security take me away for looking at porn on t'net.
Remember that MV I was going on about that parks in "my" bay? Saw the bloke yesterday. After I stopped bowing, I told him what I thought of his bike, but he didn't wanna swap. He was working on it the other day, had a sticking throttle by all accounts........don't get that on the R6!!