Throttle body balance

Flipfly

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I have a little issue.

Since adding the power commander I can't seem to get the tickover down on the ADV. The BBS are set to about 3/4 out from full in but the revs are still around 1200 rpm. I synced the throttle bodies and they are pretty close, but there is still vibration through the bars at 80+. The bike pulls like a train, but I know it's not quite right.

What is the best way of setting the BBS. I keep hearing they should be 1 3/4 turns out, but if I do that the tick over is too high.

Do I need to tinker with the TPS voltage?

The power commander is set to run off the stock maps but target 13.8 AFR.
 
Hi Phil,try doing it this way
I'll assume the throttle bodies are clean,Inc brass bypass screws,valve clearances set etc.
Check cable adjustments have sufficient free play
Engine hot,With vac gauges attached set idle speed and match the readings on the gauges using the bypass screws.
Then adjust the cables to balance the bodies @ 2000 rpm
That should get it spot on.
Mike
 
A nice simple explanation :thumby:
 
That's pretty much how I did it, but the BBS seem to have little effect until almost all the way home. I'm thinking the bike might not have been warm enough, so will try again after a good long ride. It isn't a million miles off, but it's definitely not quite there.
 
The BBS tend to get pretty gunged up , you've probably do so already but if not remove and give them a good clean ?
 
I have a little issue.

Since adding the power commander I can't seem to get the tickover down on the ADV. The BBS are set to about 3/4 out from full in but the revs are still around 1200 rpm. I synced the throttle bodies and they are pretty close, but there is still vibration through the bars at 80+. The bike pulls like a train, but I know it's not quite right.

What is the best way of setting the BBS. I keep hearing they should be 1 3/4 turns out, but if I do that the tick over is too high.

Do I need to tinker with the TPS voltage?

The power commander is set to run off the stock maps but target 13.8 AFR.

Phil,
I've seen this happen before. I'm assuming that your cables are all adjusted properly. When you richen the mixure to 13.8, the idle speed comes up 100-150 rpm because you have more power for the same air. The PC Wideband O2 doesn't get calibrated like an LC-2 so you may be richer that 13.8.

If someone before you did a zero=zero procedure your throttles are open too wide. If that's the case you will need to run zero=250, then you'll get more BBS authority.

A way to check this is to set your Wideband to 14.7, or 15.0 and you should see the idle come down.
 
I know it's not particularly relevant as I don't use a Power Commander (but might in the future :rolleyes:) but I have been having a problem with the bike cutting out and/or the tickover dropping drastically when stopping at junctions etc. I was blaming it on the servo linked brakes and 8 year old battery (ordered a new Motobatt) but after doing a motronic reset today (removed fuse 5 for 10 mins and then do throttle open/close 3 times) everything is fine :confused:
All it then needed was a slight BBS tune at idle using the Twinmax and all is well again :D
BBS are 1 1/4 out but every bike will be different relative to wear etc I suppose.

Mike.
 
I just set my tappets and end float today and struggled to get my throttle bodies to balance. Its was as mentioned earlier, the taper on the brass screws being gummed up along with the holes they fit in.
 


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