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Throttle body sync: Manometer requirements?

jacco

Riding Dutchman
Hello,

I'd like to do my own throttle body sync so that I don't have to spend the entire Saturday at the dealer again (busy summer season). From what I read on ibmwr.org it seems fairly easy to do, all I need to get is a differential manometer. What are the requirements for such a manometer, apart from two inputs so that it can do differential? I'd like to get a digital one if they're not too expensive. What are the requirements? E.g. range, resolution. Anything else I need to know before I start on this project? A manometer is the only 'special' tool I'll need, correct?

Thanks,
Jacco
 
Well, you could build one from a yardstick and about 20 feet of clear plastic tubing. This will cost you about $4.
 
The Veg said:
Well, you could build one from a yardstick and about 20 feet of clear plastic tubing. This will cost you about $4.

I know. But there are cheap used manometers on eBay. I've never done a throttle body sync, that's why I'm trying to determine what kind of range/sensitivity I'll need. I don't mind investing a few (say up to 50) dollars to compensate for my lack of skill.

Thanks anyway :),
Jacco
 
the manometers are cheaper, and easy to use, but the best too overall would be a twinmax. It is a true differential tool, and the mercury manometers use a separate tube for each TB. You have to get the tubes rising equally when balancing, and you aim for zero on the twinmax. I use the manometer for quite a while, and since I bought the twinmax, they are collecting dust now.
 
lorazepam said:
the manometers are cheaper, and easy to use, but the best too overall would be a twinmax. It is a true differential tool, and the mercury manometers use a separate tube for each TB. You have to get the tubes rising equally when balancing, and you aim for zero on the twinmax. I use the manometer for quite a while, and since I bought the twinmax, they are collecting dust now.

Thanks lorazepam. I read about the twinmax on ibmwr.org. Costs about $100 I think? But it seems that most digital dual-input manometers are also capable of computing the differential pressure between their two inputs. I was wondering if this would be a valid alternative (new approx. $200, but less when used, for example on eBay), since I could potentially use it for something else as well. But they come in a whole spectrum of ranges/sensitivities. I don't suppose we're talking tens of PSIs here, but to be honest I have no idea, really...

Regards,
Jacco
 
I have seen the twinmax listed from 79.00 to around 90.00. To me it is a no brainer tool, and makes the job so easy. I cannot comment on the digital manometer units, having no experience with them, but more than one mechanic has said that the twinmax is their tool of choice for the job.
 
lorazepam said:
I have seen the twinmax listed from 79.00 to around 90.00. To me it is a no brainer tool, and makes the job so easy. I cannot comment on the digital manometer units, having no experience with them, but more than one mechanic has said that the twinmax is their tool of choice for the job.

Where did you see it for $79, if I may ask? Cheapest I could find is $81, plus $6 shipping. Still not bad. I'll wait a few days to see if this thread yields anything else, otherwise I'll stop being stubborn and go for the twinmax solution, as you suggest. At least I'll know it'll work...

Best,
Jacco
 
I bought a 4 cylinder carb/vacuum balancer (manometer style with mercury) from Dennis Kirk for about $50 a couple of years ago and it works great on everything that I have had it on. I have not tried a twin max but I am intrigued. The mercury one I have fits great onto the boxer TBIs and let you do all the same stuff. I began by doing the zero=zero adjustment on the position sensor to get a true baseline and then began the balancing and setting the idle by the gauge too. I followed the internet instructions I found on the IBMWR site (I web searched for zero=zero) and it was simple enough for even me.
 
Having suggested the $4 unit, I think I'll eventually get the Twinmax. No worries about the fluid getting sucked into the engine (doesn't hurt the engine, but makes the job more difficult), and you can put the Twinmax in your map pocket and observe what's going on under load.
 
the $4 version. I made this a bit big. I may be compensating... IMHO - you just can't beat physical mechanics and gravity. Twinmax is a decent option from what I've read but i only had $4 at the time. :)

Manometer.jpg
 
the $4 version. I made this a bit big. I may be compensating... IMHO - you just can't beat physical mechanics and gravity. Twinmax is a decent option from what I've read but i only had $4 at the time. :)

View attachment 40122

My version is very similar to this, the only difference being that I scribed yardstick measurements on both sides of the stick. It's been a great soldier for me on my airhead and oilhead bikes however I must confess that I plan on splurging on Grok's Harmonizer in the near future....
 
I have that one

I made mine out of tube and stick like the one above. It works on all my bikes even my Kawasaki twin.

No chance for operator error or poor voltage supply (battery)..

Yes if one side comes unhooked or you use too much tube and the exhaust burns a hole in it the oil gets sucked into the throttle body and burnt. I used ATF and maybe up the stick two feet.

Had it for years.
 
Well, you could build one from a yardstick and about 20 feet of clear plastic tubing. This will cost you about $4.

+1
What I did. Works great.
I did cough up the extra for a yellow aluminum yardstick. Looks really cool with the red ATF.
 
Twinmax

Been there, done that with homemade and mercury stiks.
pay the shot and buy the twinmax. It will take all the guesswork out of things and your bike will run far better.

Best,

Will
 
Nothing works better than pure physics fluidics and gravity. I did the ATF in tubing on a stick and you cannot get more accurate results IMHO
 
Nothing works better than pure physics fluidics and gravity. I did the ATF in tubing on a stick and you cannot get more accurate results IMHO

I agree that a 2X4 with tubing filled with ATF will get the job done cheap but having tried that type of jig (bulky), mercury stix (health/environmental hazard), Twin Max (bouncy) I much prefer Grok's Harmonizer.

I also agree that while I may not necessarily get more accurate results I think it is possible to get equally accurate results in a much smaller and convenient package that I can actually ride around the neighbourhood with to check my handiwork live and in colour with my Harmonizer on the bike.

I can't do that with a 2X4 and twenty feet of tubing. Might be fun to try though! :laugh
 
I also used the plastic tube and brake fluid after a throttle cable replacement. Started so far off it was sucking all of the fluid from one side and heading for the engine. It actually sucked a long bubble through the fluid. Improved the rough adjustment, got in range and it worked fine. What is the yardstick for? I don't need a yardstick to see level.
 
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