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  #1  
Old 02-07-2004, 09:52 AM
Dee Duble Yuh's Avatar
Dee Duble Yuh Dee Duble Yuh is offline
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Default How to balance throttle bodies and adjust idle speed: R1100RS & R1150RS

Boxer Twin engines that don't have counter-rotating balance shafts vibrate a bit. It's one of those TADTS ("They all do that, sir") that we get used to. However, balancing the throttle bodies will help to keep vibrations to a minimum. You'll need some gauges, and good ones can be expensive.

Unlike most motorcycle engines, you can't just adjust the idle speed at will. You have to adjust each side, and that means keeping them in balance (again). So adjusting the idle speed is a similar task to balancing the throttle bodies.

Last edited by Dee Duble Yuh; 06-08-2004 at 03:40 PM.
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  #2  
Old 09-07-2004, 12:37 AM
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Default

Easy task as long as you hacve the right tool, mainly a Twinmax.
Unplug the vaccum hose underside of the fuel injectors that goes to teh carbon canister and connect the Twinmax to both vaccum. Sync the throttle body with Twinmax at idle then rev the engine up to 4500 rpm and check balance again, then back to idle and check again. The Adjustment is made with the flat screwdriver by turning the brass screws that are located just at the very "outside" of each throttle bodies.
After the throttle bodies are balanced, turn both flathead screw clockwise to lower idle RPM, counter clockwise to raise idle RPM.. as long as you do both left and right flathead screw in equal amount your throttle body balance should stay in tact.. or you can always check again with the Twinmax.

I watched Dhager perform adjustments on mine two three time already.
I'm sure he can offer more technique than me.
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  #3  
Old 09-07-2004, 03:25 PM
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Default Throttle Body Sync for Dummies

Here is the link for the informative and humorous Throttle Body Synch for Dummies. http://www.advrider.com/Wisdom/TBS4Dv1.0.pdf

Also, this is the link to the Internet BMW Riders website Oilhead Maintenance Manual. There are multiple instructions on performing throttle body synchs as well as other normal maintenance procedures. http://www.ibmwr.org/r-tech/oilheads...ce_2-25-02.pdf
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  #4  
Old 27-07-2004, 02:48 PM
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Question Which Gauges/Manometers

Any suggestions on whats are good vacuum gauges / manometers to use for throttle body sync and where to get them ( prefarably this side of the pond)
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  #5  
Old 27-07-2004, 03:19 PM
Oil cooled Oil cooled is offline
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Default Cheapskate carb balancer

I made one of these

http://www.airheads.org/contrib/4dollarmano.html

and used it many times with great success on my airhead. I am seriously thinking it should still do the job on my 1100rs. After all, even if the absolute inlet pressures are higher (or lower) this is a differential guage (and very sensitive too).

This may be the answer you're looking for - has anyone ever tried this approach?
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  #6  
Old 27-07-2004, 04:05 PM
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Mike,

I use the Twinmax. It is very easy to use, however it is a bit pricey as they run about $85. One main benefit is that you can connect it to your throttle bodies and check your synchronization while you ride your bike. Read the Throttle Body Synch for Dummies pdf in my post above. It describes using the Twinmax and may be helpful in determining whether or not you want to buy one.
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  #7  
Old 28-07-2004, 02:33 PM
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Default Davida vacuum gauges

Quote:
Originally Posted by MikeT
Any suggestions on whats are good vacuum gauges / manometers to use for throttle body sync and where to get them ( prefarably this side of the pond)
Hi Mike,
I can recommend the vacuum guages made by Davida. They are high quality instruments and are well damped - there is little or no fluctuation in the readings and they respond immediately to any change. The company is based near Liverpool and their website link is below.
http://www.davida.co.uk/gauges/describe.html
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  #8  
Old 02-08-2004, 12:20 PM
Oil cooled Oil cooled is offline
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Default RE: Cheapskate carb balancer

Further to my post above, I used the home made 5 carb balancer on the 1100rs over the weekend. Worked a treat .

Obviously it cannot be strapped to the bike and used on the move, but as a static balancer it works very well (for me anyway).

Link here

http://www.airheads.org/contrib/4dollarmano.html

for anyone who's interested.

I'm sure there are down sides over more expensive devices, but this is certainly good enough for me, and the bike seems to like it. You pays yer money etc etc.
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  #9  
Old 05-08-2004, 02:27 PM
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Default

I use a homemade manometer like "Oil Cooler." Works great and is easily and cheaply assembled. It's highly sensitive and has no electronics or calibration error. However, contrary to the link provided, I found that motor oil and 2-cycle oil are too heavy for the plastic tubing: they respond much too slowly due to their high viscosity. I also found that water is much too lively: it bounces around too much, and can be sucked into the injectors if they're too unbalanced. I personally use hydraulic oil, but I'm sure ATF should be just as good. (Attached is a pic of my manometer in action.)
Attached Images
File Type: jpg manometer2.jpg (60.4 KB, 413 views)
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  #10  
Old 05-08-2004, 03:26 PM
jvfante jvfante is offline
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Default Twinmax works great. No muss, no fuss

After using the home-made sync device described in numerous articles, I finally broke down and bought the Twinmax. For about half the price of a bike shop tune-up, if one looks at it in that fashion, you can have the real tool for the job that doesn't leak any fluid if you happen to drop the thing. Most of the tools in my garage were purchased with this rationale, btw.

As mentioned too, you can take a test ride with the Twinmax attached and check TB sync on the bike under load conditions, which seems a great advantage.

my 2 cents.
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