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ZZR250 Carbs need cleaning? Come on, advice needed!

Discussion in 'Bling and Appearance' started by conspiracytheorist, Mar 1, 2007.

  1. After Saturday's 'high, but legal speeds' I used more petrol than I thought and it didn't occur to me when looking at my trip meter. On the way home from the city the bike was jerky when kept on same rpms, kind of forward and back motion so I put it on reserve not knowing what else to do, but it kept doing it.

    On the way to uni the next day I decided I better go to the petrol station to fill up but stalled 2 times trying to get there when petrol wasn't at the right place to be sucked up (it was that low). Eventually got to the servo and fit 17.7 liters in with probably enough room for another 200ml. LOW

    Anyway, its still jerky on constant rpms, and I think its taking longer to revv up. So I'm guessing that I've got alot of crud in my carbs now :(

    Has this happened to other people? I should stress the bike was running 100% before I noticed any problem.

    Haven't done the carbs before. I've got some injector/carb cleaner stuff for the car but not sure if its advisable/if it would do anything. Rang up a few dealers. Freedom motorcycles in brookvale said bring it in for carb clean, and would cost $297.

    So I rang close motorcycles in redfern to get less 'give me your money' advice (they seem really nice over there). Guy said to use white rag and drain float bowls to see if anything comes out. Then after new tank if its still doing it do it again. And if that doesn't work, might need carbs done, would cost $160. Thankyou close motorcycles! Giving me advice about doing something simple instead of having to take it in.

    Anyone else have ideas as to what might be going on apart from carbs? I was reading that its possible to use carb cleaner instead semi-easily to clean them up significantly but not sure how to do that. And if anyone in sydney wants to show me how to do carbs on Saturday I'd be most appreciative :grin:
  2. hey man quick Q, what fuel did you put in the bike? 98, 95 or 91?
  3. put some Nulon Total Fuel System Cleaner into the tank. Might fix the problem, save you the trouble and money.

    my bike was having some problems with the carbie with idling all out of wack. now its all good.
  4. 91. I think I'll try adding a bit of the cleaner stuff into the tank and see how that goes. Its really dodgey cornering and having it jerk. Its not a massive jerk, but enough to upset the bike a bit.
  5. hi I had good results from nulon when my idle played up
    you can also let fuel out of the carbie through the drain tube to see if theres
    crap in there
    I've heard a very gentle tap on the carbie can work
  6. Drain the carbs before doing anything, you can also add some metho to the fuel which will absorb any water and let that pass through the carbs (if its a problem)
  7. I wouldn't worry about any of those engine clean additives for petrol simply because they're no different to what's already added to premium fuels and let's face it how much of a chance are they going to have to do anything if they're going in through the fuel system. The only proper way to clean a carb is to dismantle it - however aerosol carb cleaner can quite often be almost as effective. To use that basically all you need to do is remove the airbox and spray it down the throats of the carbs - it should dissolve and remove any dried on fuel.
  8. Thanks JD I'll give that a go this weekend. Sounds like the best thing since I'd have to teach myself to do the carbs hehe.

    I don't use premium since its a zzr so I'll try some of that and give it a bit of a fang today. Might get lucky.
  9. Does it play up at low revs under load, then clear up at high revs?

    If so, it's probably a bit of crap under one of your float needle seats. sometimes this clears by itself, by revving the bike a bit.

    You may be able to remove the float bowls on your bike, without removing the carbies. Do that if you can and spray some carbie cleaner about.
  10. The jerkyness is easily noticeable below 9000rpm. It doesn't really clear up at high revvs, but it does seem masked when I'm accelerating - only notice it when I'm sitting on constant rpm mainly.

    Yeh close suggested that I drain float bowl, not really sure how to do that but I'll have a go if today's fuel additive and thrash doesn't work. And if I'm getting down to the bowl I'd make it worthwhile and spray carb cleaner around.
  11. Higher revvs + carb cleaner additive in tank didn't do much. Did notice that with back wheel up on centrestand, in gear with clutch in, back wheel still moves. Guess clutch needs adjusting a bit as well. Oil looks pretty gunky so I'll be doing filter and new oil too. And sparks, and air filter. And chain... and float bowl. Then maybe carbs.
  12. That's normal - especially if engine is cool - coolish.

    I used to have to start my GPX in nuetral, clutch in and front brake on - or else be propelled forward a bit.

    High revs means a 2nd /3rd gear, near redline run. If that doesn't clean it out, you will need a mechanical clean. You got your tank near empty, so for sure you will have sucked gunk/grit etc into the carby system.


  13. Yeah, definitely got near reddline in 2nd/3rd. Yeah I know it will jump foward a bit when first starting up.. something to do with oil.. can't remember exactly. But this was after an hour ride of higher revving. Clev said its normal due to being a wet clutch though.

    I'll be servicing bike the best I can this weekend, and leaving the bits I can't do for the shop.
  14. do you have a fuel filter?
  15. do you have your workshop manual for your bike? this should have good instructions on how to remove and dismantle your carbies for cleaning and resetting, Also to reassemble them :LOL:

    As suggested because you got your tank down so low chances are you have sucked in some gunk, With the RGV carbies they actually have a small inline filter, which is inbetween the carbie and the hose (basically where the hose joins the carbie)
    If your bike does have these this could be a good starting point, they may just be full of rust or other grime.

    Ive got to do a similar job on my rgv soon. I just had the bike in the shop, $400 later it came out idling faster, bogging on take offs and still causing issues at high speed . BAH

    Lesson for me was always try fix it yourself first time around, especially if yah have half a clue, could save urself alot of pennies, and in my case a waste of the pennies
  16. Don't know, do zzrs have fuel filters ? :?
  17. question is do you have your bikes Workshop manual?
    If not, get it! :p

    you will be able to find it in PDF format online, there have been links supplied by people on this forum before with manuals covering hundreds of models, chances are your bikes in there.
  18. Yup I do have it, but with such poor mechanical skills I'll need dads help. I've probably used 1/3 of the tank with cleaner in it. Might be slightly better, but not much.
  19. mmm chances are if you have sucked rust or something in the cleaner is not going to help. Its mainly to remove deposits of crystalised fuel and other bits of gunk out of the carbs.

    Just have a look in your manual where it shows the carb being pulled apart, it should tell you if it has a built in filter or not.

    If not then you will most likely need to dismantle them and give them a good clean and blow out with an air compressor
  20. Arg. Anyone in sydney/nearby want to show me how to do carbs?