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carby? plugs? fuel?

Discussion in 'Technical and Troubleshooting Torque' started by WiErD, Nov 21, 2005.

  1. does anyone have any experience with these?

    when riding around fairly hard doing 13Krpm for a sustained period of time it seems to bog down after a while and even if i drop the rpm by changing gears it has the same problem.

    if i clutch it and let it idle for a few seconds its good to go again.

    but if i try to ride through it by shifting to top gear it will eventually die.

    any ideas anyone?

    im thinking maybe plugs, just want some confirmation or experience

    its a 97 gsxr750 srad

    thanks peeps


  2. 13,000 revs for a sustained period of time :shock: ???
    This is on a dyno, right, or a race track?
  3. I don't want to alarm you mate, but slap me silly and call me Susan if that isn't an imminent ring siezure you're feeling. The reason it improves with the clutch in is simply cooling. Keep it up and you're going to kill it dead. If it siezes at speed, you are quite likely to kill yourself dead as well. I used to race GSXR 750R's (and RR's) and cooling is their achilles heel. I know the feeling you describe very very well and its not healthy.
  4. Whilst everyone else is rather pesemistic... i'm gonna put my neck out and suggest fueling.

    - Is it possible the fuel filter is a little on the clogged side of things?
    - Time to flush out the fuel lines?
    - Float levels for the carbs?
  5. I agree with Koma, seems like the fuel system simply can't keep up with the demand. Look for blocks or perhaps check the fuel pump (if it's got one)
  6. JD and Koma, you might be right, but fuel starvation should not occur after riding at a constant throttle opening "for a sustained period of time", it should stop you being able to do so at all. The seizing problem I describe is a known issue with this bike when thrashed. I may well be wrong, but if I'm not, it could kill him. Just felt he should be aware of the possibility.
  7. Don't know about that, my bike works on gravity feed - if I try running it on full throttle for sustained periods (10 minutes or so) it acts exactly as if I've just run out of fuel. No problems however with using full throttle at other times or holding at around 80%.
  8. Yes, as I said, you could be right, but I also said inner cylinder ring seizing is a known issue with this bike when thrashed, and I have the hospital records and unpleasant memories to prove it.

  9. i should say *up to* 13K not like sitting on 13K constantly although it seems to happen when i do a sustained very high speed run at the aerodrome
  10. oh and is there an easy way to tell if the inner cyl ring is seizing?
  11. Isn't that what the clutch is for? Seem to recall using it for that exact purpose on a few 2 strokes in my past :D
  12. Ahh yes roarin, I suspect you are a man who knows the tinkling sound of disintegrating rings, and the realization that in about 2 seconds parts of you are going to hurt a lot.
  13. ah you guys make me sad, but then mmediately happy :)
  14. I had a Yamaha and a hondado the same thing, we corrected it by draining the fuel tank, carby bowls, replaced the fuel filter and never ever ever fueling up at the servo I bought that fuel from again, find another petrol staion with filters on the pumps.
  15. yeah you can tell by the lil person in ya head saying .... told you to up shift 3 seconds ago ... followed by the smell of burning flesh as your skin is being eaten away by the tar on the road ....
  16. Surprisingly I have never been bitten. Painted some nice squiggly black lines on the road at about 150 but caught the clutch in time :shock:
  17. I was cranked over 'undertaking' at about 80kph on the first right hander at Wanneroo, and it siezed within one revolution. I have no recollection of the rest until I woke up in the ambulance.
  18. i'd get the float hight's checked to make
    sure it's not starting to run lean up top.
    also if you have changed the muffler or
    airfilter it may need a dyno tune to make sure
    your main jets are the right size!!!!
  19. Having seen a simlar symtoms in a small truck, i would check and blow back all the fuel lines and system. this would rund low revs fine, but when pushed harder and longer, it stopped revving. Turned out to be fuel tank lining had come loose and blocked fuel lines. If revs were low enough fuel could get through. this could be the "cheap solution".

    If not you may be looking at the rings as suggested???
  20. Thats all i used the clutch on the NSR for :LOL:

    I say fuel starvation. Altho, after what inci has said I suggest getting it all checked out really, really soon and if its not fuel then bottle off till you have identified what the problems is.