carb conundrem

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Ramjam
To the on ramp
Posts: 254
Joined: Tue Apr 30, 2013 9:28 am
Country: Lebanon
Suzuki 2-Strokes: gsx 750R, GPZ 750, GT380
Location: Lebanon

carb conundrem

Post by Ramjam »

Dear All
I have just had my carbs cleaned and rebuilt after leaving the bike standing for almost two years and a build up of salt formng in many places.

Many of you advised me that the problems i had - which was that the bike wouldnt run when the choke was switched off - were down to blocked pilot jets.

THe problem is that the heads are damaged and the carb specialist here didn't think it was wise to drill them out. He was convinced that if he cleaned everything else, including the pilot jets from the other side, all would be fine.]

Putting them back, now the bike runs with choke off BUT when you open the throttle, it makes that unique noise like fuel starvation and takes a while for revs to pick up. Also, you cannot pull away with the choke off.

Could it be one of the following

THe mixture is too LEAN on all three and those external adjuster air flow screws need to be closed?

Or is it possible that my ignition timing is out? (Would that also give such symptoms?)

ALSO, is there any product i can throw into the gas tank which would clear through any blockages in the carbs?

thanks for your help and patience

MJ in Beirut
rngdng
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Re: carb conundrem

Post by rngdng »

I have used a reverse drill bit to remove pilots before, but it's not easy. They are so soft. That said, I doubt you can get the carb very clean without getting the jets out.



Lane
If you stroke it more than twice; you're playing with it.

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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: carb conundrem

Post by jabcb »

Had a stuck pilot jet on a T350 where some PO buggered up the screw driver slot.
Used the smallest drill/extractor set & the pilot jet came out surprisingly easy.
The smallest set was a 5/64 inch drill bit + #1 screw extractor.
I suspect that turning the extractor slowly by hand with a crescent wrench was key to making it easy for an amateur mechanic.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
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GT550 72 & 75
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GTandcbr
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Re: carb conundrem

Post by GTandcbr »

Hi MJ . First thing is there is nothing you can put in the gas tank that will clean your carbs efficiently. I think you are right that your bike is running lean off choke and that will be because your pilot jets can only be cleaned properly by removing them. Not only does the jet have a hole in the end metering gas there are holes in the sides that cause the gas to froth to help conbine it with the air. Its also important to get the jet out because it fits into a passage which is hard to clear normally but with the jet in impossible.
98 carb Blackbird and GT550j
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