ΠΡΟΣΟΧΗ!

whatever I do here, I do on my own motorcycle and I take responsibility for it, my own motorcycle!

If you decide to do something along these lines and break/disarm/annihilate/exterminate your motorcycle, it's totally your own responsibility!

So, as clearly as this can be said: I AM NOT RESPONSIBLE for your damages!!!!

20.07.2024

Throttle Body Sync!

We've done almost everything on the BMW so far. Except for this, until now!
Syncing the throttle bodies.

I have read this very interesting article at iBMWr.org. Seems quite easy and indeed it is, using only the bike's tools. It also applies to all the oilhead engines, either 1100's or 1150's.

What I was missing was the actual balncing tool, which I found at AliExpress and promptly bought it. It was quite cheap at around 30 euros.

Here's the link: throttle body balancer

What I got:



This is the set assembled.

First you need to adjust the gauges, in case zero is not the same.



Removing the plastic transparent cover you adjust the needle with a small screwdriver. Simple.



Now we have both gauges showing zero at the same spot!

According to the instructions, then we must first give some slack to the throttle cable on the right side TB. Undo the 10mm nut and by hand unscrew the knurled knob a little.
We need about 5mm of freeplay.



This is tight.



This has enough slack without moving the throttle butterfly. We will readjust this in the end.



Next we remove the rubber caps at the bottom of both TB's.

We connect...





...both TB's to the gauges.

next we screw both Throttle Body Big Brass Screws (TBBBS) fully in SLOWLY...





...and then we unscrew them 1.5 turns.
Mind you so far we have not started the engine.



Now it's time to start it. Let it idle until the engine oil temp is in working conditions, IE five bars on the RID.





With the gauges sitting on the front seat, we can adjust the TBBBS, first on the right side then if needed on the left side. When both gauges show equal numbers, then we are done.



One useful tip: If the needles fluctuate a lot, then we can make them fluctuate as little as possible by adjusting the white thumbscrews.

Now that we have set the TB's at idle, it's time to adjust the "high speed" too.



Holding the throttle at around 3000-3500 rpm, we see how the needles are equal.
To adjust we need to screw in the throttle cable knurled knob, to which we gave a 5mm slack earlier.



While screwing the knurled knob, simutaneously holding the throttle at around 3000 rpm, watch the gauges as they stabilize at the same spot on both clocks.
When we are happy with the result, we tighten the 10mm nut that holds the throttle cable on the TB, making sure that we do not turn the knurled thumscrew any more. This is the final adjistment.
Check once again that the idle calibration is still good!
At the same time watch the oil temperature. It should be at 5 or 6 bars on the RID.

The whole process anyway takes around 5 minutes to complete, so there's really no danger of overheating the engine.

Do not forget to cover the TB bottom nipples again with the rubber caps!!!

If you are working indoors, be VERY careful of exhaust fumes and it's advisable to use a big fan in front of the engine.