MWH
Registered user
I've used similar on a four cylinder, they do the job OK. I now use Morgan carb tune, they're a bit easier to read/ use for me.
Throttle body balancing... need advise as someone has been messing !
- Thread starter beaver
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I’ve got a pair of Daytona, oil damped gauges, it stops the needles dancing around too much.
Shame you’re not nearer you could have borrowed them.
Shame you’re not nearer you could have borrowed them.
Thanks for the kind offer mate
It’s a while since I did it, but I rigged a diy manometer with a long length of clear tube and some two stoke oil - think any oil you can see will do.
Basically, you attach the ends of the tube to each inlet port, then run each side up to the garage roof, and put a ‘U’ shaped dip in the middle. The oil sits in the bottom of the U and you adjust each throttle body so the level matches on both sides. If it’s out of balance the oil will be higher on one side of the ‘U’ than the other.
Maybe Google/Gpt it for a better explanation.
It sounds like a faf but, once you’ve done it, it’s easy, and takes about 5-10 mins to rig.
I think I hung a light weight on the middle of the ‘U’ to get a nice even shape.
You can make a more permanent one, with the U shape pinned to a bit of board with some clips. You can put lines on it to help, but as I was just trying it out and it worked well, I didn’t bother.
Those gages are cheep, but if they don’t match they are worse than useless. At least with the Manometer it shows you exactly when they are balanced.
It worked for me and once it was rigged, I left it up in the garage rafters, and coiled the tube to the inlets up.
Apologies if that is as clear as mud
let me know if you want more info.
Sent from my iPhone using Tapatalk
Basically, you attach the ends of the tube to each inlet port, then run each side up to the garage roof, and put a ‘U’ shaped dip in the middle. The oil sits in the bottom of the U and you adjust each throttle body so the level matches on both sides. If it’s out of balance the oil will be higher on one side of the ‘U’ than the other.
Maybe Google/Gpt it for a better explanation.
It sounds like a faf but, once you’ve done it, it’s easy, and takes about 5-10 mins to rig.
I think I hung a light weight on the middle of the ‘U’ to get a nice even shape.
You can make a more permanent one, with the U shape pinned to a bit of board with some clips. You can put lines on it to help, but as I was just trying it out and it worked well, I didn’t bother.
Those gages are cheep, but if they don’t match they are worse than useless. At least with the Manometer it shows you exactly when they are balanced.
It worked for me and once it was rigged, I left it up in the garage rafters, and coiled the tube to the inlets up.
Apologies if that is as clear as mud
let me know if you want more info.Sent from my iPhone using Tapatalk
people
rtfm.
twice.
rtfm.
twice.
Go on, I gave it 5 mins but what does ‘rtfm’ mean?
Edit: Sorry, googled it…
Sent from my iPhone using Tapatalk
Looking at doing the balance on the throttle bodies and the bods on YouTube don’t seem to mention the stepper motors they just use the carbtune and adjust the lock nuts either way to achieve the balance .
Exactly what I thought
I'd first start cleaning the throttle bodies - crud all around will give random numbers... make sure each butterfly and the body is spotless (brake fluid is a cheap and effective cleaner)
on the R1200 air cooled bikes it specifically states NEVER touch the gap for a closed throttle - dealers used to just throw any that have been tampered with in a skip, and fit new
third point idle stepper motors is an electronic calibration - and these days both aftermarket diagnostic tools have a method to lock out the stepper motor to do balancing - however you should never balance the closed throttle set up - its not really where you ride... at low speed you ride on a just open throttle and its the balance here that you want correct...
and of course the bike will run silly on a worn out TPS giving random info to the ECU - they wear out, swap one at 30k for a new one and the change in engine behaviour can be startling
on a GS I do it like this - the best thing is to service the bike, get the valve clearances optimised, fit new TPS, clean the throttle bodies, get to operating temp and use a big fan to keep the bike cool as you do it - then hold the carbs just open via the throttle cable at around 3k rpm and balance them here - switch off snap throttle open and closed multiple times, take the bike for a ride - comeback start again - as they magically change, and further refine in another step ! - anything else won't ride as well as it could
on the R1200 air cooled bikes it specifically states NEVER touch the gap for a closed throttle - dealers used to just throw any that have been tampered with in a skip, and fit new
third point idle stepper motors is an electronic calibration - and these days both aftermarket diagnostic tools have a method to lock out the stepper motor to do balancing - however you should never balance the closed throttle set up - its not really where you ride... at low speed you ride on a just open throttle and its the balance here that you want correct...
and of course the bike will run silly on a worn out TPS giving random info to the ECU - they wear out, swap one at 30k for a new one and the change in engine behaviour can be startling
on a GS I do it like this - the best thing is to service the bike, get the valve clearances optimised, fit new TPS, clean the throttle bodies, get to operating temp and use a big fan to keep the bike cool as you do it - then hold the carbs just open via the throttle cable at around 3k rpm and balance them here - switch off snap throttle open and closed multiple times, take the bike for a ride - comeback start again - as they magically change, and further refine in another step ! - anything else won't ride as well as it could
