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Discussion Starter #1
Hi all,

I've just replaced the throttle cables and put new fuel/vac lines between the petcock and carbs.
The bike fired up and ran ok but after a minute I noticed a pool of fuel under the centre stand.
Thinking it may be a leak on the new fuel line I took the tank off and rigged up a temporary tank.
When I supply fuel to the carbs I get a stream of fuel coming out of the overflow from the carbs.
There is also fuel pouring out of the exhaust joints.
I'm guessing that the floats are stuck and hence not cutting the supply once the bowls are full.
Is this something that just suddenly happens? I didn't mess with the carbs at all apart from to connect the nipple of the new cable. I tried blowing/sucking through the main fuel intake and also the overflow. I also tried gently tapping the float bowls with a piece of softwood to try and fix the problem.
Does anyone have any other ideas to try and fix this or is it a carbs off and dismantle job for the weekend?
Thanks in advance for any pointers.
 

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yeeeouch. I'm not seeing the year of your bike, but these EX's are certainly ageing, and showing it.

Your observation probably correct...something lodged between needle and seat, could be worn needle too.

I'd urge you to order carb kit and have on hand, replace needles and all seals/orings while you're in there, also setting float height.
If you are able, a wet test prior to reinstalling the carbs is advisable. May save an R and R.

FWIW....a good idea as any carbed bike reaches 10 years old to perform a preemptive, full carb service, replacing all consumables, readjusting/renewing where necessary.
 

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classic fuel pipe renewal syndrome. when you replace the pipe onto the petcock a little sliver of rubber is nibbled off and goes down the pipe into the float bowls. floats as it's rubber and then jams into the float valve keeping it open. usually takes a min or two before fuel start peeing from the overflow. fit a filter.
 

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classic fuel pipe renewal syndrome. when you replace the pipe onto the petcock a little sliver of rubber is nibbled off and goes down the pipe into the float bowls. floats as it's rubber and then jams into the float valve keeping it open. usually takes a min or two before fuel start peeing from the overflow. fit a filter.
the original intent of the Kaw filter protecting final fuel entry point at carb rail

https://www.ex-500.com/50-carburetors/23180-easy-fuel-filter-alternative-yes.html
 

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Discussion Starter #5
Thanks guys.

It's a 1996 version with 26k miles.
The previous lady owner didn't use it much so I'd guess that the carbs haven't been looked at in a long time.

It may be time to do as D'man suggests and replace all the carb perishables.
 

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Discussion Starter #6
Got in from work, carbs off.
Both you guys got this one absolutely spot on.
The guilty culprit was found loitering at the bottom of the chamber that houses the needle attached to the float.
My little old girl is chugging along nicely again and not vomiting fuel everywhere.

Many thanks .
 

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Discussion Starter #8
The story continues.

I decided to do a thorough job an bought an Ultrasonic Cleaner.
On stripping the carbs down the mixture screw settings were completely different between the two carbs.
I've now set both carbs to two turns out.
I've also replaced the needles/springs and washers with new ones.
I'm not sure if this is relevant but I'm also running a pair of aftermarket black widow exhausts.
The bike ticks over great, and runs fine under 4000 rpm. When you wind it fully open it doesn't accelerate straight away but burbles and almost seems to misfire, then it will catch and accelerate through the "rough zone". Then if you change up, the same thing happens again.
The fuel is fresh so could any of you kind gents tell me whether this sounds like it's set to lean or too rich for the setup and would I need to try 1 1/2 turns or 2 1/2 turns to improve this problem?

Thanks for any guidance that may be offered.
 

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The exhausts would pose a problem. Stock exhaust seems to be the way to go. From my limited understanding with an aftermarket exhaust you need your pilot jets to be about a size larger for it to run decent and even then it's never gon a run as good as stock. (don't quote me on that however, again limited understanding)

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The exhausts would pose a problem. Stock exhaust seems to be the way to go. From my limited understanding with an aftermarket exhaust you need your pilot jets to be about a size larger for it to run decent and even then it's never gon a run as good as stock. (don't quote me on that however, again limited understanding)

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that's not actually correct. when a exhaust is specifically designed to fit a bike by the aftermarket company it will be designed with the jetting and settings in mind. they even design it around the original equipment so it fits as if it was and original fixture. for instance mine has a Motad 2 into one. running stock jets and settings. works perfectly. you may however encounter issues if you just stick on some generic pattern cans. however that is not the OP's issue it runs fine up to 4k well outside the range of the pilot circuits at 4k it is more likely to be needle and slide issue. note for the OP if it was fine before you did the carbs but now has issues it is certain that whatever you did has upset something and it is now not as it was.
 

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I would pull them off again and go back over them, insure the cv diaphrams have no holes and the black caps/covers are on correctly.

Insure all of the jet passage ways are good and clear.

The pilot screws should be closer to 2.5 (stock)/3 (better performance some say) turns out from fully closed.

Have you seperated the carbs, if so they need to be synced (butterfly valve thing). I ddid mine by eyeballing the distance from the edge of the valve to one of the jet holes in the main carb passage (forget the name).

Was the bike nice and warm when you did this or was it still a bit cold?
 

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Discussion Starter #12
A day in the garage, 3 turns out, and she is now running as well as she has ever done :)

Many thanks to everyone who has chipped in along the way.

Thanks guys.
 

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that's not actually correct. when a exhaust is specifically designed to fit a bike by the aftermarket company it will be designed with the jetting and settings in mind. they even design it around the original equipment so it fits as if it was and original fixture. for instance mine has a Motad 2 into one. running stock jets and settings. works perfectly. you may however encounter issues if you just stick on some generic pattern cans. however that is not the OP's issue it runs fine up to 4k well outside the range of the pilot circuits at 4k it is more likely to be needle and slide issue. note for the OP if it was fine before you did the carbs but now has issues it is certain that whatever you did has upset something and it is now not as it was.
He never stated if it were slipons which in that case would be generic. But I did say I could be wrong sorta so ehh

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He never stated if it were slipons which in that case would be generic. But I did say I could be wrong sorta so ehh

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hi, I'm not being a arse here. but the OP said they were black widow cans. black widow like Delkevic make pattern exhausts for specific bikes whoever ordered those pipes would have to say which bike they were going on so as to get a perfect fit the exhaust sent would then be suitable to use on that bike with stock settings. a generic can is just that one off the internet that may or may not fit properly or be calibrated for any particular bike. just saying""
 
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