Balancing throttle bodys

[Spoons]

Can anyone tell me where I can get a vacuum tool to balance throttle body's?
Mine are well out of sync and need doing and I'm damned if I want to go to BMW to get it done. Thanks

 

[brassmonkey001]

Do a search for "Manometer" - you'll find lots of information there about carb balancing including how to make your own manometer.

 

[cookie]

having used a home built manometer (crap, but might have been my design), and presently owning a mercury carbtune, a carbtune II and a twinmax, i reckon that the carbtune II is an easy winner



in case you're wondering, i just can't resist buying tools sometimes

 

[digga]

must say... after having my bike serviced ( ABS/Servo and and all that!!) i was pleasently surprised at the improvement that it made.
whether it was a combination of Throttle bodies and Tappets or just the throttle body adjustment i don't know...but its a damn sight 'crisper' now

 

[cookie]

I can't help thinking owners who claim their bike is better for having the tappets adjusted are misguided. all that does is stop their valves burning.

Valve clearances are almost always done at service time when the oil is changed and throttle bodies are synced, and they account for the increased smoothness perceived. Likewise, all this valve adjustment needing to be done with two feelers at once is more bollocks, though i do do it that way myself

Sorry, I wandered right off topic there

 

[Pukmeister]

I also use a "Carbtune2" with good results (4cyl version from my old jap rocket days).

 

[ianboydsnr]

having used a home built manometer (crap, but might have been my design), and presently owning a mercury carbtune, a carbtune II and a twinmax, i reckon that the carbtune II is an easy winner



in case you're wondering, i just can't resist buying tools sometimes

I have a carbtune mercury and a carbtune 2 and a set of vacuume dial guages and find the home made manometer easiest, maybe i'm strange

 

[cookie]

or maybe you built a better manometer

 

[Boon]

I also use a "Carbtune2" with good results (4cyl version from my old jap rocket days).

ditto

 

[ianboydsnr]

or maybe you built a better manometer

I still cant resist buying tools though

 

[digga]

What are the factors that affect the Throttle body sych's then.

Oil and tappets make no difference.
Is it a placebo effect of a'professionals' oilly rag?

 

[cookie]

What are the factors that affect the Throttle body sych's then.

Oil and tappets make no difference.
Is it a placebo effect of a'professionals' oilly rag?

the throttle butterflies need to be physically in sync, i.e. start and move together. that can make a huge difference to how the bike feels.

new oil will make the bike seem smoother. my contention was that the effects of adjusting the tappets alone was undetectable to the rider.

 

[Stewart H]

My aquarium tube manometer works a treat, the only time it did not was after a throttle body swap when it was out of range and the motor tried to drink the oil

Stewart

 

[Pukmeister]

Spoons, one point worth noting when performing TB synch yourself is that the possible adjustment range is huge, but the actual adjustment needed to get back into perfect synch when performing balancing is typically very small. In other words even a tiny bit out of synch is very noticeable to the engine smoothness, and a small tweak can make a huge change.

When you are set up to do the synch, you only need to make small adjustments to one throttle cable adjuster and then raise/lower the revs to check synch. Obviously recheck after each small adjustment is made until you get it spot on, and also after you have re-tightened the locknut on the adjuster (in case tightening it alters the setting).

I originally took lots of care in getting mine absolutely spot on, and at the service I just did it was still spot on and needed no further adjusting.

 

[Mzokk]

My aquarium tube manometer works a treat, the only time it did not was after a throttle body swap when it was out of range and the motor tried to drink the oil

Stewart

Mines Got TQF In it.

 

[Stewart H]

Mines Got TQF In it.

Mines on LHM, green Citroen blood about sae 5 I think.

Stewart

 

[Spoons]

Thanks for all the replies.
I am smiling to myself. The need to get throttle bodies in balance is simple if you don't there is no way the two cylinders will run in perfect sync causing all sorts of running problems. Also if your valves are out same thing will happen.
If you throttle valves don't lift at the same time how can it be possible to have the same air fuel mix in both cylinders? If your valves are out then you will have different durations. To loose short duration to tight longer duration (and the chance of burning your exhaust valve)
If you don't use 2 feeler gauges at the same time it is nigh on impossible to get correct valve adjustment.
Bad throttle sync and valve adjustment are one of the biggest causes of surging in R bikes!! Now that will open a can of worms.

 

[digga]

the throttle butterflies need to be physically in sync, i.e. start and move together. that can make a huge difference to how the bike feels.

new oil will make the bike seem smoother. my contention was that the effects of adjusting the tappets alone was undetectable to the rider.

I know WHY they need to be in 'sync' but what causes the the variation in the first place?

Stretch / wear in cables, Vibration.??

When you think of all the clever technology associated with bikes/cars these days, its a bit of an antiquated system is'nt it?

 

[MattW]

When you are set up to do the synch, you only need to make small adjustments to one throttle cable adjuster and then raise/lower the revs to check synch.

Isn't idle sync done on the big air screws on 11xx's? (With secondary sync on the cable adjusters for higher revs?

 

[Steptoe]

If you don't use 2 feeler gauges at the same time it is nigh on impossible to get correct valve adjustment.
.

What utter rubbish.