TB Sync problem?

[SecretSquirrel]

I've been playing at TBS'ing on my 1150GS!

High speed sync (ie anything above 1800rpm) is fine. Tick-over sync is not proving easy to set?

I've checked the cable sleeve adjustment and the choke and neither seem to be holding the throttle open AFAICT.

To get the TBS correct, the tick-over rpm has climbed to 1600!

1100rpm is only achievable with the LH brass screw turned all the way in? Adjusting the RH screw only sends the sync further out?

The throttle cable adjuster on the LH side doesn't appear to have been touched by the previous owner and I'd hope the throttle stop adjusters have remained unmolested too.



Perhaps Mr Steptoe can help?

 

[ianboydsnr]

try removing the brass screws and cleaning them

 

[SecretSquirrel]

try removing the brass screws and cleaning them

You think that may help? OK, I'll take a look
As a matter of interest, the bike has covered 34k and is an '04

Well, I've cleaned a certain amount of black deposit off them, so we'll see what difference it makes tomorrow.

 

[dancata]

I don't get it, what is wrong with my TB's? I sync them at 3500 rpm, then on a long test ride, upon deceleration, I can hear a missfire in the exhaust. This happens rarely, like one in 50 km's or so. Could there be water in my gas or do I need to check the tb's shafts for wearing?

Bike is a 95' 1100gs with 108k km on the clock.

Thanks,
Dan.

 

[MattW]

I don't get it, what is wrong with my TB's? I sync them at 3500 rpm, then on a long test ride, upon deceleration, I can hear a missfire in the exhaust. This happens rarely, like one in 50 km's or so. Could there be water in my gas or do I need to check the tb's shafts for wearing?

Bike is a 95' 1100gs with 108k km on the clock.

Thanks,
Dan.

Occasional exhaust popping on the over run is normal GS behaviour. My '94 1100 does it, my mate's brand new GSA does it.

The most likely cause of exhaust popping is air leaks on the exhaust side (not the intake, hence nothing to do with TB's or sync). Check for leaks in the exhaust system (or just accept it as normal).

 

[sproggy]

Well, I've cleaned a certain amount of black deposit off them, so we'll see what difference it makes tomorrow.

The black deposit is quite normal. It can also be worth squirting some carb cleaner down the holes when the brass screws are removed in case there's any dirt stuck in there.

Your problem may be related to an air leak somewhere (rubbers between the TBs and the heads) - have you checked for splits in the rubber or the clamps not done up properly?

If it was me I'd slacken off the cables completely before trying the balance at idle in case there's any tension in one of the cables that's opening one throttle slightly. Of course then you'll have to re-balance at higher revs but it's a good thing to check. And have you checked that the throttles both close properly against the throttle stop screws?

 

[ianboydsnr]

Try checking the coil caps, faulty ones can do funny things at tickover

 

[bart2181]

secret squirell have you tried removing all tension in both cables first with plenty of slack in each you then set your idle sync.if you are trying to set the idle after the 2-3rpm setting there may be tension in one of the cables making idle sync impossible.

 

[zdaveuk]

check the RH throttle cable to make sure its seated correctly, not at the adjusted but follow it up and under fuel tank it goes into a larger sleeve there and if it comes unseated can cause the sort of symptoms you describe

 

[sockpuppet]

Guys the thread is over a year old, there was a new questions asked half way down

 

[sproggy]

So why (dancata) resurrect a year-old thread to ask a question that's nothing to do with it?

Is it any wonder people answer the OP's question?

 

[ianboydsnr]

Guys the thread is over a year old, there was a new questions asked half way down

I knew that, I posted on it for a laugh

I also knew it was about a 1100, but what would be the fun in answering that