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Post by oldninjaron on Dec 26, 2006 20:03:12 GMT
Seasons greetings to all.
Picked up a bike the other day that started first time on four pots pulled away once warmed up and initially in town felt like flat spot at about 3k revs. I might add at this point that this bike is a ZX6R and will be my hack for winter. I thought nothing of it as I wanted to wait for the open road but then it would not rev past 4k revs then here we go kangaroo petrol action perhaps going on to 3 pots then at least twice cut out in town but sometimes restarted 4 and other times on less than 4 pots.
Managed to get home - sometimes it went great guns up to 80/90 then it would miss/go downto 3 pots then rev. No back fires. Bike had been MOT'D last September and had only done 200 miles since.
Has anybody ever let fuel go off? If so what were the symptoms somewhat like the poor description above I will flush out tank after checked fuel steady from tap and empty carbs and refuel at least. I guess had better check vacuum hoses not kinked trapped etc.
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Post by BADGER on Dec 26, 2006 21:35:20 GMT
This reminds me of the HT leads shorting, + you say something about petrol going OFF, so has the bike been sitting around for a long time, as far as i know petrol doesnt "go off".
Did you find out if the same pot is the one not firing..? Might be a good idea to change the plugs.
Hope this helps.....
any other ideas guys..?
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Post by oldninjaron on Dec 26, 2006 21:51:01 GMT
Good point, you never know with this sort of problem. Perhaps it is one of those urban myths abouth fuel going off but I have heard of "lacquer bein stripped off" frim inside of cars blocking jets. Also possibility of water in the fuel blokes garage was metal with condensation dripping off roof.
Last time I spotted HT lead problem was when car was missing so hoisted bonnet switched off garage light and watched the wondrous arcing display on the leads bit more awkward with bike unless extend fuel hose and vacuum from tank off bike as you do with carb balance.
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Post by Les on Dec 27, 2006 14:15:35 GMT
It is a bit of a myth about petrol going off, however, it could have some moisture in it, if the bike has been stood around for a while. and 200 miles in 5 months is a fair amount of standing, then you can get condensation. Stick in a bit of carb icing due to the cold weather, and there you go.
Although I have never had a problem with the Rex and carb icing, it is the only Kwaka that I have not.
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Post by ZRX Gremlin on Dec 27, 2006 16:08:49 GMT
Only a bit.
I bought a bike a while ago that hadn't been run for years and it didn't want to know. Minor fiddling with the electrics did nothing.
Cleaning out the carbs worked for about 3 minutes until the fuel from the tank got into them again.
Cleaning out the carbs a second time AND replacing the fuel in the tank sorted it. Fuel going off IMO isnt' a myth but doesn't happen overnight either.
Getting back to oldninjarons question.
I worked on a friends ZX10 a while back. That had been off the road a while before he bought it and displayed similar symptoms, never being that good and occasionally being bl**dy awful. In this case the intake rubbers on the carbs had gone brittle with heat and age and were allowing air into the carbs.
Might be worth a look? :donno:
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Post by ZRX Gremlin on Dec 27, 2006 16:11:54 GMT
Oh, and remove the tank anyway, there should be enough fuel in the float chambers to allow the engine to run for long enough before running out of fuel to see any sparks jumping.
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Post by oldninjaron on Dec 27, 2006 18:56:26 GMT
I will use all this advice when I get back home from Xmas holidays. I am tempted to clean out tank anyway then using prime drain/flush each carb in turn using drains.
I may have some spare ht leads coils as part of SREX loom purchased some time ago to substitute as necessary and might as well get some new plugs while I am at it.
Please feel free to offer any more wisdom
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Post by BADGER on Dec 27, 2006 21:09:34 GMT
Or you could always look for the advice on HERE
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Post by bikesnoopy on Dec 30, 2006 13:40:47 GMT
Id agree with Lord Grem's diagnosis...
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Post by firmhand on Dec 30, 2006 14:49:46 GMT
It is a bit of a myth about petrol going off, however, it could have some moisture in it, if the bike has been stood around for a while. and 200 miles in 5 months is a fair amount of standing, then you can get condensation. Stick in a bit of carb icing due to the cold weather, and there you go. Although I have never had a problem with the Rex and carb icing, it is the only Kwaka that I have not. I've always been lead to believe that unleaded petrol goes off after about six months can evaporate in the carbs leaving a gluey residue. Know you can buy a "stabiliser" that you add to the fuel to prevent this. I don't no anything about this subject so wouldn't want to start a debate just curious and going on what i've been told .
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Post by oldninjaron on Dec 30, 2006 19:01:58 GMT
Much appreciated all advice so far will let you know how I get on in the New Year - when I get home.
Seasons greetings and all that malarky!!!!!!
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Post by oldninjaron on Jan 13, 2007 9:25:50 GMT
Well 2007 is finally arrived and time to sort this screaming jeepers ZX6 - their web page is nowhere near as good as this one. Much joy in oldninjaron's garage as removed tank and found tank fuel pipe kinked - outer rubber damaged but not leaking so that always heading towards flat - replaced it (god knows why this bike has gravity feed fuel rather than vacuum assisted? ) and the tickover was ultra smooth and revved feely with usual high revs on choke but smooth. I finally decided to take her out but although started first time did not rev freely on choke and when set off running rough again, would not rev but always ticks over roughly - not sure whether, fault intermittent eg disappeared for a while or, something else. Not sure if you would describe the way this bike runs as surging as sometimes revs but not smooth then tries to die but ticks over or what? Fully accept previous suggestions but not tried yet as thought I had sorted a ful starvation fault.
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Post by Les on Jan 13, 2007 10:27:52 GMT
have you felt the header pipes, when she is running rough, if we have a warm or cold one it will give some indication on which pot or pots she aint firing correctly. Have you had the plugs out to give them a quick eyeball, be interested to know what colour they are, or if they are wet or oily.
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Post by oldninjaron on Jan 13, 2007 19:15:35 GMT
Hi Trucker
Spent all day on this mother. Tried twice to isolate possible missing pot on both occasions all exhaust headers appeared much the same.
Isolated fuel filter, pipe direct to fuel pump, fault still apparent. Pulled plugs - all mid brown. With no spares available difficult to track down possible HT probs but all looked fine no damage etc. Drained each carb in turn - no sign of water or muck, clean as a whistle. Checked fuel flow from tank on main/reserve - steady. Drained tank and inspected fuel tap no obvious probs or debris in tank.
Last time went out seemed to go v well for about 1/4 mile then started to run rough and engine died three times with what felt like fuel starvation eg run out of fuel but every time would restart and tick-over. On the fuel side since plugs all dry and decent colour this only leaves fuel pump?
Outside possibility of HT/coil probs but difficult to tell.
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Post by Les on Jan 14, 2007 13:37:30 GMT
:hmm: check the tank vent, try riding it with the filler cap undone, and see what happens.
Obviously, not with tank fiiled to brim with petrol.
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