GS1000G BS34SS with a bit of whim

[Alexander]

Hi guys,
my gs1000g 20000km just doesn't want to get back to perfection.
Bs34ss dismantled and cleaned, replaced the float shafts, adjusted to 22.4, jets disassembled and cleaned, except the cylinder with the membrane and the pin which seem ok,
replaced the float valves.
I reassemble everything and I have a situation like this: at idle ok, it drowns if I give gas slowly, if I open quickly it's fine, with the petrol jet at 2.5 rpm,
if I move I move the vacuum but it doesn't disappear, at high rpm it seems to go like a projectile, the clutch slips.
I change the fuel screws and put back the steel ones, I think the OEM ones are sharper than the aftermarket brass ones and the music doesn't change.
As soon as it is turned on, the first cylinder takes longer to heat up than the three.
The candles removed are the first two completely white, the 3rd and 4th just hazelnut.
I think in the end I will send the carburettors to Switzerland to an HTM racing company for a complete cleaning and overhaul.
So I will try to exclude the carburetors and look for the problem if it continues elsewhere​​.

 

[SkiDooFritz]

Alexander,

You are right, getting the carbs professionally cleaned will make diagnosing your issue much easier. Hopefully you can reinstall the carbs and be on your way.
I read your previous post, and saw that you noted the boots (rubber connections) between the airbox, carbs, and intake ports may not be in great shape. I know you replaced the airbox, but the connection between the carb and the engine may still be bad.

I am not a professional, but have rebuilt and tuned many of these older bikes- based on the description of your bike’s behavior and the previous advice you’ve taken from other members here, I would advise that you check for air leaks. If there are cracks in the rubber boots or an improper seal between the boot and carb, you’re sucking in too much air. This can cause erratic idle, poor or unpredictable performance like what you are experiencing, and certainly lean cylinders indicated by your white spark plugs. Any intake leak means your fuel and intake system is not sealed to the outside, and therefore no amount of carb cleaning and tuning can properly control performance!

An easy way to check for leaks is to spray a small amount of water or carb cleaner onto the rubber boots while the bike is idling. If there is a change in the sound or rpm, then your intake system is sucking in the spray substance and is not sealed to the outside.

Of course I cannot be certain because I have not seen or heard your bike, but I almost always start by checking for vacuum leaks when tuning an older bike.

I hope this is helpful, let us know how you proceed. Good luck!

 

[Alexander]

SkiDooFritz,
thanks for your tips. I have two OEM filter boxes, one with new tires and one in worse condition, every time I try to refit the rubber manifolds they are not aligned and do not fit, they are off-centre I know but still the difficulty in inserting them into the air intakes of the carburetors is a lot, if you have a trick please enlighten me. What I was able to do to replace the filter box is to make the rubber cones free but out of the seat and they certainly get air, I will try to rotate them now that they are mounted and see if they center themselves with their hole, but I find it difficult. I don't understand what prevented them from making holes corresponding to the pitch of the carburettors, perhaps the BS34SS are an evolution and they adapted the filter with the tires but not with the holes​

 

[Alexander]

Alexander,

You are right, getting the carbs professionally cleaned will make diagnosing your issue much easier. Hopefully you can reinstall the carbs and be on your way.
I read your previous post, and saw that you noted the boots (rubber connections) between the airbox, carbs, and intake ports may not be in great shape. I know you replaced the airbox, but the connection between the carb and the engine may still be bad.

I am not a professional, but have rebuilt and tuned many of these older bikes- based on the description of your bike’s behavior and the previous advice you’ve taken from other members here, I would advise that you check for air leaks. If there are cracks in the rubber boots or an improper seal between the boot and carb, you’re sucking in too much air. This can cause erratic idle, poor or unpredictable performance like what you are experiencing, and certainly lean cylinders indicated by your white spark plugs. Any intake leak means your fuel and intake system is not sealed to the outside, and therefore no amount of carb cleaning and tuning can properly control performance!

An easy way to check for leaks is to spray a small amount of water or carb cleaner onto the rubber boots while the bike is idling. If there is a change in the sound or rpm, then your intake system is sucking in the spray substance and is not sealed to the outside.

Of course I cannot be certain because I have not seen or heard your bike, but I almost always start by checking for vacuum leaks when tuning an older bike.

I hope this is helpful, let us know how you proceed. Good luck!

SkiDooFritz,
I opened a specific tread and got lots of advice on the correct position of the rubber cones.
Yes, the fittings are outside the seat and it is certain that they get air. I sincerely hope this is the problem of everything and not the beginning of a series, but I want to be optimistic, thanks​

https://www.thegsresources.com/_for...729-gs-1000-g-filter-box-this-absurd-creature

 

[SkiDooFritz]

Looks like there’s a lot of good info in the new thread. I hope this is the fix. Glad to help!

 

[Alexander]

Alexander,

You are right, getting the carbs professionally cleaned will make diagnosing your issue much easier. Hopefully you can reinstall the carbs and be on your way.
I read your previous post, and saw that you noted the boots (rubber connections) between the airbox, carbs, and intake ports may not be in great shape. I know you replaced the airbox, but the connection between the carb and the engine may still be bad.

I am not a professional, but have rebuilt and tuned many of these older bikes- based on the description of your bike’s behavior and the previous advice you’ve taken from other members here, I would advise that you check for air leaks. If there are cracks in the rubber boots or an improper seal between the boot and carb, you’re sucking in too much air. This can cause erratic idle, poor or unpredictable performance like what you are experiencing, and certainly lean cylinders indicated by your white spark plugs. Any intake leak means your fuel and intake system is not sealed to the outside, and therefore no amount of carb cleaning and tuning can properly control performance!

An easy way to check for leaks is to spray a small amount of water or carb cleaner onto the rubber boots while the bike is idling. If there is a change in the sound or rpm, then your intake system is sucking in the spray substance and is not sealed to the outside.

Of course I cannot be certain because I have not seen or heard your bike, but I almost always start by checking for vacuum leaks when tuning an older bike.

I hope this is helpful, let us know how you proceed. Good luck!

Dear, you were right, it all depended on the seal of the rubber manifolds, the ones I have are not yours and to put them on I had to use silicone, it seems that your OEMs cannot be found online.
In acceleration it is perfect, minimum 1200.
The only thing I noticed is the first piston, it takes a while for the muffler to heat up, then it goes away.
I dismantled the pipes, cut the wire and reassembled them, I saw inside above the spring like a resistor, it was very encrusted and the two ends came off, I didn't put them back on, I think the current passes anyway. The clutch tends to slip when it comes into torque, I hope it's due to the bike being stopped and that it stabilizes over time, I don't think it needs to be done again at 25K km. Today I'll do a nice ride to try it but it's already different music​

 

[SkiDooFritz]

Phenomenal, great to hear your bike is running like it should. I will go forth and brag about how wise I am.

Cheers!