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avanti

Which manometer to buy to check/adjust throttle???

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avanti
I went to the dwyer site noted in the throttle-adjustment thread here at the Forum and found... scads of options, none of which had any particular meaning to me as appropriate or "best" for our purposes.  Any help???  (no, I don't want to make one, thanks)
 
Many thanks, in advance!!!
 

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pauljr
I've got a twinmax which I've used for years and like it just fine. Had a few manometers in the past they work fine but the mercury means storage is kind of fussy. A google of twinmax will give you some options.

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avanti
Thanks, pauljr.  I'll do so... 
 
And, as I recall, of the gazillion that dwyer listed, many did not take mercury, but either a green or red "liquid."  But, still I don't know which for what, mainly the length differs for all models.
 
anyone else???
 

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bmwpowere36m3
I used two of these, bad thing is you have to pinch the vacum line to keep the gauge from jumping around 
 
http://www.amazon.com/dp/B00PXSMBCY/ref=sr_ph?ie=UTF8&qid=1430878760&sr=1&keywords=vacuum+gauge
The only downside is you have two gauges that might be off +/- some amount… However the "benefit" is you can read the absolute value of vacuum.  With a simple manometer there is no deviation, since your only looking at the difference in fluid heights.
 
 
 
I made my own manometer with a yard stick, fish tank tubing and 2-cycle oil.
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yamahaha
 

I made my own manometer with a yard stick, fish tank tubing and 2-cycle oil. 
 

That's what I'm going to do.
 

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bmwpowere36m3

I made my own manometer with a yard stick, fish tank tubing and 2-cycle oil. 
 

That's what I'm going to do.
 
 
It works great and if the vacuum difference is too high, worst case you'll suck in some 2 stroke oil. The only downside is it's super sensitive, so sometimes it appears that the difference is large, but in fact it's not. I did the calculations before to relate the oil height to mmHG.

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rotaryryan24
I used two of these, bad thing is you have to pinch the vacum line to keep the gauge from jumping around 
 
http://www.amazon.com/dp/B00PXSMBCY/ref=sr_ph?ie=UTF8&qid=1430878760&sr=1&keywords=vacuum+gauge
The only downside is you have two gauges that might be off +/- some amount… However the "benefit" is you can read the absolute value of vacuum.  With a simple manometer there is no deviation, since your only looking at the difference in fluid heights. 
 
 
I made my own manometer with a yard stick, fish tank tubing and 2-cycle oil.
 
That is why I switched the gauges at one point to see if they were reading the same value.
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You do or don't
Then your dead.
 
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One-off-fabrication.myshopify.com

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yamahaha
That's what I'm going to do.
It works great and if the vacuum difference is too high, worst case you'll suck in some 2 stroke oil. The only downside is it's super sensitive, so sometimes it appears that the difference is large, but in fact it's not. I did the calculations before to relate the oil height to mmHG.
Good to know, thanks. Would heavier oil help? Perhaps inline restrictors?

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bmwpowere36m3
It works great and if the vacuum difference is too high, worst case you'll suck in some 2 stroke oil. The only downside is it's super sensitive, so sometimes it appears that the difference is large, but in fact it's not. I did the calculations before to relate the oil height to mmHG.
Good to know, thanks. Would heavier oil help? Perhaps inline restrictors?
 
 
Restrictors would help if the oil height was pulsating, which it does a little depending on the engine and RPM your checking at. Heavier oil or fluid would "desensitize" the manometer or produce a smaller oil height difference for a relative vacuum difference.
 
Experiment.... but I'm happy with my setup.

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rick
I have an old set of 4 gauges. I'll hook them up in pairs to a vac source to see any variances. The set came with clamps to pinch off the hose, but I haven't used them in a long time. Now my hoses have small orifice constrictions down near where they get attached to the motor. It's a must with free moving gauges, but probably helpful with any set-up
 
Unlike carbs, the air screws on these things are only meant to sync idle vac. There's really no point in even looking at 4k as we can't change it. A little blip of the motor a couple times to sorta simulate riding is OK.

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bmwpowere36m3
I have an old set of 4 gauges. I'll hook them up in pairs to a vac source to see any variances. The set came with clamps to pinch off the hose, but I haven't used them in a long time. Now my hoses have small orifice constrictions down near where they get attached to the motor. It's a must with free moving gauges, but probably helpful with any set-up 
Unlike carbs, the air screws on these things are only meant to sync idle vac. There's really no point in even looking at 4k as we can't change it. A little blip of the motor a couple times to sorta simulate riding is OK.
Is the idle synch adjustment done via mixture screws (air) or is it on the throttle shaft, changing the relative position of the throttle plates?
 

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avanti
After reading all this (thanks, again, btw), which is similar to what has been reported on other sites (based on several "googles"), I ordered a Twinmax. So, we'll see. I appreciate the imput!

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rick
I have an old set of 4 gauges. I'll hook them up in pairs to a vac source to see any variances. The set came with clamps to pinch off the hose, but I haven't used them in a long time. Now my hoses have small orifice constrictions down near where they get attached to the motor. It's a must with free moving gauges, but probably helpful with any set-up 
Unlike carbs, the air screws on these things are only meant to sync idle vac. There's really no point in even looking at 4k as we can't change it. A little blip of the motor a couple times to sorta simulate riding is OK.
Is the idle synch adjustment done via mixture screws (air) or is it on the throttle shaft, changing the relative position of the throttle plates?

There's an air screw on each TB. The left side TB is the reference and not touched. Only the screw on the right TB is adjusted to balance vac at idle. And it really is only adjusted at idle to make up for any machining variances in that circuit. Can't really call it a mixture screw as it does not really adjust mixture. It's just allowing the same air for each TB at idle.  
The throttle plates are linked together solid by a thru shaft. 
 
With an IAC (idle air control) valve controlling idle, those plates will be completely closed in the TB bore at idle (no air gets past those plates at idle), so it's important not to mess with the throttle stop screw either. 
 
 
 

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gregjet
Actually I have just had a thought on the air screws and the selfrising throttle/dieing problem.
To me it looked like a lean mixture at idle stall on any of the videos I have seen ( mine doesent do it...yet).
First all the fuel comes from the EFI and is controlled by the tables so that won't be the problem ( or at least it is extremely unlikely).
So what if the problem is with a manufacturing process fault when they set the idea air screws. OR the screws move after. I haven't looked. Are the adjuster screws loctited or do they have a locknut?
If there was some swarf left in a air galley and then became dislodged after the bike was set then used that idle air supple would then run lean. Again if one side air adjust is not locked ( by some method) it could back off and that side would then run lean at idle.
When you first stop the pooled fuel in the intake would be enough to let it idle at a rich enough mix but as it idles that would be used up. That would give exactly the condition we see on the videos with it idleing fine, then rpm raise then die.
Just a theory don't crucify me if it's wrong.
The worst thing is if it was crap in the  set side it won't be removed by adjusting the side that is meant to be adjusted as it will always run lean.
 

Go forth and modify my son...go forth and modify...

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bmwpowere36m3
Actually I have just had a thought on the air screws and the selfrising throttle/dieing problem. To me it looked like a lean mixture at idle stall on any of the videos I have seen ( mine doesent do it...yet).
First all the fuel comes from the EFI and is controlled by the tables so that won't be the problem ( or at least it is extremely unlikely).
So what if the problem is with a manufacturing process fault when they set the idea air screws. OR the screws move after. I haven't looked. Are the adjuster screws loctited or do they have a locknut?
If there was some swarf left in a air galley and then became dislodged after the bike was set then used that idle air supple would then run lean. Again if one side air adjust is not locked ( by some method) it could back off and that side would then run lean at idle.
When you first stop the pooled fuel in the intake would be enough to let it idle at a rich enough mix but as it idles that would be used up. That would give exactly the condition we see on the videos with it idleing fine, then rpm raise then die.
Just a theory don't crucify me if it's wrong.
The worst thing is if it was crap in the  set side it won't be removed by adjusting the side that is meant to be adjusted as it will always run lean.

 
 
I think the stock fuel maps ARE likely the cause in combination with a closed loop system trying to maintain higher AFRs at closed throttle and steady state, low load conditions. Add to that, maybe too low of an idle....

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gregjet
Wouldn't we all have it then, all the time?
I don't have it though I have the Aussie model and prob mapped different which may support you statement.
 

Go forth and modify my son...go forth and modify...

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mjh937
I just had it happen once when it was brand new and a friend was riding it. It was before we discovered the clutch switch was unplugged. It has not happened again since. I am not sure if this is connected or why it would be.

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rick
I think the stock fuel maps ARE likely the cause in combination with a closed loop system trying to maintain higher AFRs at closed throttle and steady state, low load conditions. Add to that, maybe too low of an idle.... 
 
 

exactly!  

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anips
I bought the CarbMate from Amazon to sync my throttle body this past weekend, a bit on the expensive side but I figured might as well use the money to buy this rather than spending it to pay someone to do it for me. I was also trying to wait for the Harmonizer that some guy on advrider sells but it looks like it won't be in stock till the end of this month.

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cndnmax
I bought the CarbMate from Amazon to sync my throttle body this past weekend, a bit on the expensive side but I figured might as well use the money to buy this rather than spending it to pay someone to do it for me. I was also trying to wait for the Harmonizer that some guy on advrider sells but it looks like it won't be in stock till the end of this month.
 
I was looking at the harmonizer also. I just don't know it it's worth the money. How often do these throttle bodies need to be synced, I wouldn't think that often.

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anips
I was looking at the harmonizer also. I just don't know it it's worth the money. How often do these throttle bodies need to be synced, I wouldn't think that often.
Manual says after the first sync, then every 6000 miles.. but I believe some people say they just do it when they "feel" it needs a sync.

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