Carb Set and Balance

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R-Bandit
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Location: Johannesburg, South Africa
Carb Set and Balance

Post by R-Bandit »

Hi,

Is there anyone out there who could let me know what my carbs should be set to? I live in Johannesburg, South Africa approx. 3000ft above sea level.
It's a variable cam bandit 1991 (GK75A).
It isn't currently running and think it might be my carb, I've just placed an order for new o-rings all round, but will take aprox. 2 weeks.

The elements I think need setting in the mean time are:
Pilot air screw
Pilot Needle
Main jet Needle (currently on the middle slot)

Any other info would be great.

Thanks Ryan
M1KE
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Re: Carb Set and Balance

Post by M1KE »

Pilot air screw i'd have set at about 2 turns out. Main jet needles in the right place. And i dont know what you mean by pilot needle.
R-Bandit
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Re: Carb Set and Balance

Post by R-Bandit »

Thanks M1ke

Still no luck unfortunately. Is there a chance that when my valves were replaced that the mechanic screwed up the cam timing, and if so is it a job I should try and rectify?


Thanks
Ryan
M1KE
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Re: Carb Set and Balance

Post by M1KE »

I'd doubt that he did get the cam timing wrong but using the pdf manual from here would show you how to check the cam timing and if needed fix it. Check all the valve clearances while your in there too.
R-Bandit
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Re: Carb Set and Balance

Post by R-Bandit »

Thanks.

Will try this week. Will get back to you.

Ryan
R-Bandit
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Re: Carb Set and Balance

Post by R-Bandit »

Okay,

So I took my bike in to a guy I got referred to. Turns out the guys I had it at before had put my cams on upside down and swopped the shimms... assholes. :o
But the bike is finally running again, until it gets warmed up.
The new mechanic seems to think it is to do with the pickup being faulty and the temp sensor not working, is this a possibility? and is it possible ti fix the pickup instead of replacing it?
I can't believe what a bugger its been to get this bike running!

Thanks for any help in advance.
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Variablevalves suck
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Bike owned: GSXR Carb o'ring kits supplied
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Re: Carb Set and Balance

Post by Variablevalves suck »

Hi Ryan,
Are you 100% sure the cams are correct. I ask as most people even mechanics think that you just adjust the standard shims as per all other bikes, when in reality you have to adjust the normal shims, low setting, then move the cam follower shafts to the high posistion and adjust some tiny tophat shims that arnt at first odvious and then adjust the gap between the high and low settings using the old style pin and locknut, so two shims and three ajustments for every cam. They can only be set with the follwers in the correct position and it is a massive job, hence my user name and Suzuki not using it on any other motors. Dealers want three times the money to adjust the cams! If any are wrong you could have problems when the motor warms up and the gaps close. You can check the pickup with an ohm meter and its between 90 and 110 ohms when testing the two wires from the left side casing.
R-Bandit
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Re: Carb Set and Balance

Post by R-Bandit »

Thanks VV-S

I'm kinda new at the mechanics stuff and still learning that your name is spot on.
The mechanic who is busy working on my bike is pretty old school and worked on a couple of the same bikes before (VVT/C), so I'm trusting that he knows what he's doing.
Before I took it to him it wasn't even running at all and I had no idea what to do. since, he's got it going and this seems to be the only problem left, So I should be getting it back tomorrow.
If there are still problems I'll forward him your advice and see what he has to say.
Otherwise holding thumbs and will post another reply when I have some more news.

Any other advice would def come in handy, thanks.

- Ryan
R-Bandit
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Re: Carb Set and Balance

Post by R-Bandit »

Great

The pickup issue has been resolved!!! :grin:
It is however having a fluctuating rev problem while idling. Seems to drop then increase intermittently.
I am pretty sure that it isn't a regular carb issue as I have cleaned, jetted and set the carbs by the book.
I have however found an electric sensor on the side of the carbs which i'm not quite sure does. It looks as though it has been previously tampered with,
and want to know if this is the norm on this bike. If it is then is there anything I can do to fix it? If not it might be a replacement carb that the previous owner
switched and didn't realise the implications?

Any help would be great.

Thanks
Ryan
vivo
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Re: Carb Set and Balance

Post by vivo »

The SP models of the GSXR have a throttle position sensor on the left side of the carbs, could this be the same :?:

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