THROTTLE BODY BALANCE

Mac One

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Hello
I use a Carbtune ( the sticks, not mercury ) to sync the TBs in my bike but i think i've only got it spot on once, and the difference was amazing. I think they're ok to get the balance in the ballpark but i think the important bit seems to be the fine adjustment at the end.

I've been looking around for a reasonably priced alternative ( that doesn't require a degree in engineering) but the reviews on most of them are really mixed, some people love the Twinmax, others say it's a waste of money, you can't get the Harmonizer any more :blast

Has anyone tried the DigiSync, http://thedigisync.com and if so, how did you get on with it.

Cheers
 
I use a Twinmax, far from a waste of money.. You need a GS911 (or possibly new OBD connected software) to park the stepper motors so they don't interfere with the syncing, but if not available, I would go ahead with cable adjustment anyhow.
 
I use a Twinmax, far from a waste of money.. You need a GS911 (or possibly new OBD connected software) to park the stepper motors so they don't interfere with the syncing, but if not available, I would go ahead with cable adjustment anyhow.

The trouble i found with that was that it wouldn't park the idle steppers until the bike was well up to temperature, then as you're faffing about, the bike starts to overheat so i just disconnect them now.

I got good advice, on this forum, to concentrate on the point where the TBs start to open/pickup, and that helped greatly.

Prior to that i was holding the throttle at 3000 rpm...bike roaring and overheating me burning my arm on the engine and dropping spanners (a sight to behold) I'll take another look at the Twinmax. :thumb2
 
The Twinmax is shite. had mine for a week before selling it on UKGSer.

The buyer ( i did warn him :D), another well known spanner juggler on UKGSer, kept it a week longer then me before he to moved it on.

And he agreed with my findings :D
 
The Twinmax is shite. had mine for a week before selling it on UKGSer.

The buyer ( i did warn him :D), another well known spanner juggler on UKGSer, kept it a week longer then me before he to moved it on.

And he agreed with my findings :D


I've ordered the DigiSync, it's coming from across the pond so i'll let you know how i get on with it when it arrives. If it's any good maybe you'll swap the Harmonizer for it. :D
 
The Twinmax is shite. had mine for a week before selling it on UKGSer.

The buyer ( i did warn him :D), another well known spanner juggler on UKGSer, kept it a week longer then me before he to moved it on.

And he agreed with my findings :D

Why was it so dreadful? It appeared to work for me in that the bike ran better after balancing the throttle cables with it.
 
I use a pair of Davida gauges that I’ve had for over thirty years. Just warm it up, good excuse for a long ride, connect it up, two ten mill spanner’s and check at 2,3 and 4 thousand revs. I’ve never parked the steppers and I have a GS911.
2011 TC.
 
Hello
I use a Carbtune ( the sticks, not mercury ) to sync the TBs in my bike but i think i've only got it spot on once, and the difference was amazing. I think they're ok to get the balance in the ballpark but i think the important bit seems to be the fine adjustment at the end.

I've been looking around for a reasonably priced alternative ( that doesn't require a degree in engineering) but the reviews on most of them are really mixed, some people love the Twinmax, others say it's a waste of money, you can't get the Harmonizer any more :blast

Has anyone tried the DigiSync, http://thedigisync.com and if so, how did you get on with it.

Cheers

Yes, Digisync is brilliant. Very easy to use and gets balance spot on. Really great bit of kit
 
I made a manometer filled with scotoiler blue oil(no longer regained as had no chain)
Set the u tube on a metre long piece of wood with each end of the tube connected to the corresponding vac take-off points.
The viscosity of the oil helped to damp out transient variation at low revs.
Disconnect the stepper motors, prewarm the engine and it takes just a few minutes to get the balance. I tend to try for best balance at around 3k revs, held steady by a throttle lock.
Ain’t got no GS911 to play with.
 
Do the idle actuators affect the bike throughout the rev range or only at idle ( some disconnect them, some don't ).

When are they in the optimum position to balance the throttle re unplugging them, would you unplug them before you initially start the bike or do they park when you cycle the ignition and then unplug them.
 
bearing in mind its air cooled and the exhaust headers glow cherry red within 3 min of starting, the sensible comment about having a powerful fan pushing air through the oil cooler and over the exhaust headers is key to trying to balance throttle bodies correctly
 
Interesting reading; my TBs haven't been synchronised for at least 9 years and 20,000 miles, possibly even longer. Am planning to get my mechanic to do them for me this summer. Bike seems to run fine - so I have no reason to believe they're 'out of sync', but what would I see/hear if they were out of sync, and how might I see an improvement if they were out of sync and then synchronised?
 
Runs smoother, less vibration, better mpg. No big deal if slightly out
 
I'm no engineer, but this makes sense to me as explanation for why sync with Digisync seems spot on

http://thedigisync.com/why-the-digi-sync-is-simply-better.html

Every type of synchronisation tool i have (and i have many different types) has a damper to stop any erratic readings, including my old mercury guages from 30 years ago.

I helped develop the original Harmoniser made by Grok, and the mk1 had a terrible pulsing on the readings, gradually improved, with a few other beneficial tweeks until it was ready to be released to the market, which incidentally was the Mk4 version... I still have all the original models. :D
 
I used the DigiSync today, warmed the engine up to 2 bars, unplugged the idle actuators, throttle locked it at 2,000 rpm ( the instructions say low revs for best results ) and adjusted the right hand TB until the numbers matched the ones on the left and locked it off.

Once the bike was warmed up the job only took 5 minutes. I took the bike out for a short run and it's going really well.

The numbers on the digisync display hold really steady, fluctuating only 1 digit now and again.

I might connect the carbtune to it tomorrow just to see the readings out of interest.

I don't know if its spot on or not, if not, i think it's really close and it's very easy to use. :thumb2
 


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