engine problems please help

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xfireblade
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Joined: Mon Jul 28, 2008 6:43 pm

engine problems please help

Post by xfireblade »

i have just bought a zxr400 L and i am haveing problems. could anyone give some advice please. these are the symptoms.
when rideing bike doesnt rev past 6000rpm. on the stand in neutral it revs all way up. the bike says its a uk bike with uk clocks. all cylinders are working, changed plugs, air filter fuel and fuel filter but still no joy. any advice welcome. thanks
zimm
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Re: engine problems please help

Post by zimm »

sounds like blocked jets..

or water in the carbs, amounts to the same thing.

drain the float bowls and see if that fixes it, if not strip and clean the carbs.
xfireblade
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Joined: Mon Jul 28, 2008 6:43 pm

Re: engine problems please help

Post by xfireblade »

thanks for the advice, but its strange that it revs correctly on paddock stand in neutral and also running through gears on paddock stand, but as soon as you ride it, it goes back to max 6000 revs and a chokeing feel to it. its almost like there is some sort of restricter on it. looked at the cdi and it has blue sticker with letter 'm', from previous posts i have read, this seems to be the unrestricted version and it is a uk bike. could it have a 33bhp restrictor on it, and what type of restrictor are they? :smt017. the bike is a L3
zimm
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Re: engine problems please help

Post by zimm »

33bhp restrictors are just washers in between the carbs and the head

i still think its water in the float bowls or something else blocking a main jet or two.

fact that it spins up ok at a standstill/under no load would point this way too.
Last edited by zimm on Wed Jul 30, 2008 10:22 pm, edited 1 time in total.
parby81
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Re: engine problems please help

Post by parby81 »

need to do it under load dude, as the man says
These things are sent to try us!!
MillaMeter
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Re: engine problems please help

Post by MillaMeter »

Hi,

I had this problem before, I'd say it's water in the carbs. Take the tank off and drain all the carbs into a glass jar or something and look to see any water sitting at the very bottom of the jar (unleaded is lighter than water so you should see the fuel floating on top of the water)

Or.... as RedexRob would say, shove some Redex in the tank.

Regards

Rich
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RedexRobB
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Re: engine problems please help

Post by RedexRobB »

MillaMeter wrote:Or.... as RedexRob would say, shove some Redex in the tank
Well done that man! :smt002

Although im not 100% if it will shift the water. Certainly get the carbs apart and clean them out tho with carb cleaner to properly remove any water, then run some redex through.
Jesta

Re: engine problems please help

Post by Jesta »

Do you know how long the bike was stood still for before you bought it? Id look to the floats, you can rev right up with very little fuel but under load youll need more petrol to get it moving and at 6000rpm itll be drawing in a good amount, enough to drain the carbs quick enough for them to have trouble refilling if the floats arent adjusted correctly, if you ride to 6000rpm it doesnt cut out immeditately right? Does it cough and splutter like your running out of petrol? If you try riding to 6000rpm or until you have the problem then let off the throttle and just allow the bike to roll along without you using the throttle for a few seconds, lets say 10seconds then try to get back to where it had problems, if it gets back up there and gets a little further up the rev range then that means the carbs have refilled themselves so will be floats hung too low or a big kink in the fuel pipe.

J
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