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2006 GSXR600 & 750

Discussion in 'Bike Reviews, Questions and Suggestions' at netrider.net.au started by nearlyempty, Sep 15, 2005.

  1. Buell have done it for years, Kawasaki's new ER600 is going to do it, Suzuki's GSXR1000 couldn't really be bothered going all the way, but the new for 2006 GSXR600 & 750's will both feature underslung exhausts.

    Looks like the fashionable (it was always a fashion really as it didn't really make any technical sense) underseat exhaust is dead. Long live the under-engine exhaust!


     
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  2. Here's a thought.
    The Mazda 6 car is alone in having the injectors at the front of the engine and the exhausts exiting on the rear (firewall) side of the engine.
    Why do bike engines HAVE to have the carbies/injectors at the rear and the exhaust coming out the front and creating complication and height going under the engine??
     
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  3. They don't. Have a look at the Petronas.
     
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  4. Trouble is, anything at the front tends to get covered with crap, which is one of the reasons why they tend to put the exhaust there (the airbox is another problem).

    Several manufacturers have played around with reversing the intake/ exhaust, but for varied reasons they tend to go back to the traditional format.
     
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  5. Sorry, mate, not that familiar, is that a race bike or a road bike? I guess they can do whatever they like on a race bike, but I would have thought you could lower a bike engine in the frame by an inch or two at least if you didn't have to accommodate the exhaust pipe(s) under the engine. (Not telling, asking!!!)

    {Saw your post when mine went up, I was typing while you were!!!}
     
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  6. No worries, here's a link I have found (Petronas is around a third of the way down the page).

    http://www.motorcycle.com/mo/mcyossef/03_SBK_Tech/index.motml

    Alternatively try the Petronas website, www.fogggypetronasracing.com (I think).

    The bike was designed for racing, but there is a road version of the same.
    I think that was one of the reasons they went for this design, so that they could lower the engine. The trouble is, the exhaust silencer and pipework still needs to go somewhere, which in the case of the Petronas is high up, under the seat. Compared to traditional bike design their solution should be a bonus as they have been able to rid themselves of some pipework and lower the engine, but when compared to something like a Buell, which keeps the exhaust and pipework low down, the benefit they gain is quickly wiped out.

    An exhaust is a long, weighty piece of kit. Getting rid of this (or at least keeping it close to the c of g) should give a real benefit, especially to turning the bike.
     
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  7. Many years ago, a few European competitors did the reverse cylinder thing on TZ Yamahas. They found that it did provide a straigher intake tract as well as a less complicated exhaust route, but the intake of air was disturbed by the front wheel and so was unreliable.

    All the same, I can't see why, when the airbox is best placed when the air entering it is cool, they can't solve that problem.

    The other thing is that modern exhausts need a certain length in order to achieve correct scavenging and performance and making them shorter by reversing the cylinders could adversely affect that aspect too.
     
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  8. Yamaha did a reverse cylinder TZR250 -yes the road going version in I think 1988 or 89. Nearly bought one but shifted countries instead :D . One of my mates did buy one & it went really well, better than the previous model but they only lasted for one model year I think. The TZ race bikes were reverse cylinder till they followed everyone else down the V twin route. Aaah. Brings back memories of watching the mighty 250 strokers flogging the GSXR1100's & FZR1000's round the local race track :D
     
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  9. :? Aerodynamics....not causing various levels of damage to your can in even the slowest of drops.
     
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  10. There is basically nowhere for the exhaust to be routed efficiently, without heating up the frame excessively, and then the rider.

    In order for the exhaust to clear the frame, the engine would have to be slanted back, not good for weight distribution.

    Bear in mind that on most v configuration engines there is an exhaust/s at the back of the engine, and if you have seen how tight things can get in there, you will see what I mean.

    This concept may be easier to achieve on 2-strokes as the pipe thickness before the expansion chambers is significantly thinner than a 4-strokes.
     
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  11. I understand that, all good technical stuff.

    Back to the new Suzukis (sorry for the digression.....)

    We argued about this a while ago, so perhaps Suzuki is going for a lower centre of gravity by keeping the exhausts low......
     
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  12. As long as they can make the exhausts meet EPA and noise requirements, I guess it doesn't matter where they put them.

    Most riders are going to put on an after-market pipe anyway, aren't they?

    Does interest me, though, how they can achieve good scavenging with a pipe that short.
     
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  13. Not sure if you are being sarcastic there...

    I for one was pleased to see that the 05 gsxr1000 retained a 'conventional' exhaust as a I am not a fan of underseat zorsts. The 06 model R6 also proves that underseat exhausts are not the only alternative to the traditional style. Hurrah!
     
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  14. Good scavenging is not needed with todays electronics.

    Sure, scavenging will provide some slight power/torque benefits lower down in the rev range, but have you noticed that bikes with these short pipes (and the 06 R6 must be the most extreme example yet) are models which are mainly interested in gains at the top end?

    EDIT 06 R6 pic: http://i19.photobucket.com/albums/b171/Cammo78/06R6.jpg

    Check out the MotoGP bikes for short pipes...
     
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  15. Of course anyone who has ever owned a mini will know that it's possible to have both the air intake and exhaust on the same side of the engine.
     
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