fuel spraying out of carbs

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willpisme
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fuel spraying out of carbs

Post by willpisme » Thu May 08, 2014 7:04 pm

My 1wg is running very lumpy and is missing on 2 and 3 occasionally.

Took the airbox off and ran it to find a fine mist of fuel blowing out of all the carb's when giving it throttle.

Is this because the valves arent shutting fully? Just wondering what the solution is likely going to be before i fully strip it down.

willandrip
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Re: fuel spraying out of carbs

Post by willandrip » Thu May 08, 2014 7:42 pm

They all do that sir !

It is because you have the airbox off.
When were clearances last checked ?
A red box doth not a Snap On make.

willpisme
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Re: fuel spraying out of carbs

Post by willpisme » Thu May 08, 2014 8:02 pm

ah thats great to know thanks! I was getting rather worried about it.

The clearances are next on the list to check.

Does the airbox have a drastic effect on the bikes running? I managed to get it sat on, but its unbelievably hard to get the rubbers over the carbs.

willandrip
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Re: fuel spraying out of carbs

Post by willandrip » Thu May 08, 2014 8:19 pm

There are approx. 25,679 topics/threads on the FZR General and Workshop sections if the archives are included from 2002.
Of those topics ; about 20% relate to owners failing to get the air box ,which is Critical with a capital C, for Mikuni
downdraught carbs to operate correctly thought the rev/throttle opening range, to fit properly.

Drastic is the very word to describe the effects of incorrect fitment.
Buy new rubbers or search for a recent topic by Drunken Monkey where a silicone hose "bodge" is linked.

1WG covers a spectrum of 4 models with 2 possibly 3 different airbox inlet rubbers.
We shall have to presume you own a Genesis; in which case new rubbers are still available.
A red box doth not a Snap On make.

willpisme
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Re: fuel spraying out of carbs

Post by willpisme » Thu May 08, 2014 8:37 pm

thank you. Ill do some searching

dobbslc
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Re: fuel spraying out of carbs

Post by dobbslc » Thu May 08, 2014 9:29 pm

If it's missing on 2 & 3 it could be the coil, it supplies those two cylinders.
:smile:

Evilchicken0
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Re: fuel spraying out of carbs

Post by Evilchicken0 » Thu May 08, 2014 10:43 pm

Does sound like a coil, check the electrical connection to the coils, undo the block connectors one at a time and check they're not corroded. Check the wires aren't chaffed either.

willpisme
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Re: fuel spraying out of carbs

Post by willpisme » Fri May 09, 2014 11:36 am

Got the airbox back on finally. Runs spot on above 8k just really boggy below

willandrip
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Re: fuel spraying out of carbs

Post by willandrip » Fri May 09, 2014 1:16 pm

The hint was there; you never followed up ! ;)

Is it a Genesis; or should it have an Exup valve ?
A red box doth not a Snap On make.

Evilchicken0
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Re: fuel spraying out of carbs

Post by Evilchicken0 » Fri May 09, 2014 1:27 pm

willandrip wrote:The hint was there; you never followed up ! ;)

Is it a Genesis; or should it have an Exup valve ?
Well I saw what you did there :)

I'm betting it's an exup model

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