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A 250cc that sounds like an F1 car.....

Discussion in 'Modifications and Projects' started by gpxkermit250, Dec 23, 2008.

  1. ok,... please dont tell me that spending money on a 250cc is a waste of time and that I should be updrading rather than considering cashflow on my current GPX Sowing Machine!

    I know anything beyond general maintainence is not going to get me a $$ return potentially, however I love my bike and due to wanting to buy a house/go on holidays etc etc, 2009 and even 2010 it will be 250cc for this little green kwaka.

    So, in the interest of pursuing a hobby, I am going to splash some cash on my bike about May/June - Sex it up with some real sticky tyres, various cosmetic enhancements, touch of paint where needed and a major service. That will keep the love going no probs.

    So, to digress.. I have already modified my exhaust with some lovely air vents.. Cost me $12 for the drill bit and sounds great. Anyway, I was passed by a bike recently that was at lowish speed/high revs, and I swear this thing sounded like an F1 car- IM pretty sure it was a 250cc, could be wrong though. It was just off its head, and by the looks of it, wasnt a standard pipe...

    So, my question is - If I was to spend the money on a Gpx exhaust, to get that "of ya head" scream, what am I looking at (price, new? second hand?, can it be done?, can i go to a single?, will it make a difference, what the basic to the most expensive) etc etc..

    Putting it out there to anyone who has done this to a 250cc and never looked back... Thanks in advance... Greg
  2. When I think F1 car I'm thinking high pitched scream. Unfortunately to really get that you need an extra couple of cylinders and a redline somewhere around 18k.
  3. Or CBR250R /RR , FZR250R, ZXR250, Suzuki Across
  4. whatcolour was it?
  5. It was Blue and White... At first I thought maybe a CBR, but now after doing some CBD Eye Candy Footpath research, I think it may have been a GSXR600.. Still not sure

    Alas, but Im still looking into what is possible with a 250 to get it sounding 'fully sick' as some may say...
  6. Shorter the pipe, the louder it'll b

    with 250's .. the pipe has to be shorter than the Screaming Demon Cans, which means you'd have to modify your own.
  7. I don't think your going to be able to get that F1 scream given the GPX's engine configuration (Parallel twin right?). The sound you heard most likely came from an inline 4.
    However I have a pipe on my 250, and really like the sound it makes. So if you have the cash by all means :wink:
  8. Yup, need an i4, or take your exhaust (and rev limiter) off :grin:
  9. Heh i'm not sure how long a GPX would last at 18krpm :LOL:

    I once accidentally kicked my cbr250rr down a gear and saw an indicated 20,000rpm. Now THAT sounded like an F1 car.
  10. my old GSF250V bandit sounded like an F1 car, simply because the exhaust was bigger than what i have on my gsxr1000 now...

    loud and straight through, dont know what the pipe was....

    fark that bike used to pull some looks
  11. Forget the noise factor, save your money and spend it on brakes, brake lines, suspension and as you mentioned, tyres. Or is it just image you're after? :?
  12. you could probably sell the GPX since those things sell like hotcakes and get an older CBR600F with the amount of money you want to spend on modding the GPX

    Probably best not to mod the 250 since it will only lose in resale value - most L-platers will go for standard, unmodded bike if they have a choice.

    However if you do prefer to keep the kwaka get some good tyres first, that'll keep you smiling for a while.

  13. HAYSEY - Awesome!! Yep, thats kinda what Im after... Ok, so was it too loud but you just risked it (Epa/Legal RWC issues) What sort of pipe and how much??

    ROARIN - Yes, I will be pretty much making it as safe as possible as my first priority - Tyres, Service, new chain/sprockets etc and then if there is any left over, perhaps a nice little pipe. I reckon my bike looks great, for what it is.. and if sounded ridiculous also, well... that would just add to the wank factor for me... Ive always driven older cars with big exhuast etc,. so Im just a 34 year old P Plater really.. cant move on and dont want too! : )

    SIRROGER - good idea.... would be hard to let go of such a trusty bike for unknown baggage, Best I be off to bike sales etc to have a squiz.
  14. you want a fzr or a cbr.... ive had a gpx (zzr same engine) and have now got a fzrr.... completely different engine sound... i say ditch the gpx and go with a fzr :LOL: 18 grand and cooked feet - they rock!
  15. there are some bargain basement cbr600F's out there..

    hmmm, that has really messed with my head now...

    Plus the FZR prospect....

    its all good to know in my quest for a loud - cheap - good looking bike..
  16. a tidy CBR600F would be quite a natural step up from the GPX where's an FZR is a little on the radical side, in my opinion, comfort and ridability wise. Especially the older ones, in your price bracket.
    Try out a CBR if you can for yourself and decide if you want to stick with the 250 after riding it.
    Either way good luck with whatever decision you make :)
  17. Thanks mate.. Good call.. Nothings going to happen till June (off restrictions and will have the budget for either decision (keep and spend or get rid/upgrade)

    Will post back on this thread when it happens (whatever that is)
  18. Hi All,

    Latest and final update on the Quest for My GPX to sound like Niki Lauders F1 Car.

    I drilled out 4 more holes in both cans on Saturday (photo 1 is the initial tweak) and took it for a test ride. As I booted it up through the gears I get an almighty popping noise from the right Muffler - The Baffler has come screaming out. I pull over, grab it and head back to the garage. Only one choice.....Remove the left baffle as well coz it just looks to too obvious. After alot of drilling, grappling, swearing and sweat the left Baffle came out as well..

    Took the bike for a ride, and well all I can say is "Nascar comes to Melbourne"..

    Ridiculous.... Obnoxious....Throaty.... My GPX now sounds like a cross b/w a 600CC Dirt Bike and a Lawn Mower with no exhaust...(thats the best i reckon it will) - Then went onto Youtube and searched for GPXs with Muzzys, Yoshis etc and I shite you not, for the price of a drill bit I have a not dissimilar sound happening.... : )

    I will go to a wreckers and get a 2nd hand GPX System real cheap just in case I ever need to change it over.

    So, in addition to this im getting 2 new tyres, new chain/sprokets (1 less tooth on the front and 1 extra on the back) and some front end work done...thats it.. I have closure on the next phase of 250cc adventures till the next itch needs to be scratched...

    With a major cosmetic detail to clean him up (wire brush, steel wool, tooth brush, touch up paint, elbow grease etc) the love appreciation of the sound and look of my bike is well and truely enough to get me through another year.

    The Cbr600f will be a very likely prospect one day, but little Kermit with his sowing maching looks and power but raving lunatic sound lives to ride another day.

    Worth mentioning that I think I have lost a little bit of power, but jeez it revs to the red line heaps quicker now with no baffles.

    THanks to everyone for your advice and interest, appreciated..Greg



  19. My old Suzuki Across sounded like an F1 at about 16k RPM with a few drill holes thru the baffle :)
  20. im not sure how keen you are buddy but if you read up enough on the net and have a crack at tuning your carby (or carbies?) you will get more power out. more airflow makes her run lean. if you richen up the brew just a smidge you may find a larger smile on your face (she will really take off when you crank it open).

    my brother had a go at the 2 carbies on his across and got it running a fair bit smoother / faster.