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I've been playing around with my new TwinMax and having always done it before using the homemade plastic tube/yardstick/transmission fluid balancer, I am a little confused by the difference in the "reading" levels. With the homemade tool I was able to see better the actual ebb and flow of the vacuum of each side. However, I do not reject technology and concede that the TwinMax is probably the more precise instrument to use. I'm just preplexed by it.

I have just about got the synch nailed down but I want to play some more when the weather is nice. However, as I studied the cable system I came up with a question that needs the brains and experience of a more skilled mechanic/engineer person like Al or Robbie.

My question is this: When adjusting the throttle cable play at the throttle, how does that affect the play at the TB? Or does it even? To make sure there is enough play at the TB to settle the butterfly (not sure of the correct terminology) at idle, can one just loosen the play at the throttle end?

This has always been a concern of mine when adjusting only the right side TB. At one point I chose to ignore that advice and adjusted the left one to give both adequate play.

Some sage and precise advice on this matter would be wonderful?

Boxer....

The idea of the slight clearance at the throttle is to allow the butteflies to fully close against their mechanical stops and not having the main accelerator cable, the one from the thorttle, keeping one or both open. If you turn the throttle and let it snap back you can hear the metallic sound the butterflies make when they strike the stops.

I don't think there is an adjustment at the throttle, the adjustment is taken at each of the TB cables.

From my perspetive if one understands what is taking place the adjustments are a breeze....let me expand

The mechanical TB stops should not be tampered with, they establish the starting point for adjusting the fuel system (I'll author a more detailed installment)

The TPS should not be disturbed also, it provides a signal to the ECU of when the TB(S) are closed, fully open and somewhere in between.

That being said you want this to happen

The TB butterflies fully closed against their stops with no throttle applied.

The TB butterflies fully open at full throttle.

About 1100 rpms at iddle with the two TB(s) flowing the same - in balance.

The two TB(s) in balance at 2,500 rpm to 3,000 rpm - high speed balance

Being that you have some room to roam, in them thar Georgia hills may I suggest that you leave the TwinMax installed and take the bike for a ride, that way you can look at the product of your efforts.

One last thing.....all cables stretch, specially when new, after the cable has taken it's "set" you will find out that the sync is merely an exrcise since things won't be changing that much.....

I hope that I answered your question and didn't ramble too much

Regards

Al

This is the part that confuses me.

I don't think there is an adjustment at the throttle

There is a cable adjustment at the throttle side and the high-idle switch side. These two are connected at a box under the tank to the two cables that run to the TBs. I haven't been inside that junction box and don't know what the connections physically look like. If I loosen the cables at the throttle and/or the fast-idle switch side, theoretically this should loosen the cables down at the TBs. But for some reason, something..call it ESP...I dunno!...tells me this will not happen. DOES it happen!? And if it doesn't, why not?

My concern: If I continue to use only the right side TB cable adjustment to synch the TBs, won't I at some point have one of the TB butterflies not completely closing at the throttle closed position?

Man! I wish I could get in there and take it all apart to see how it works. But I seem to always have parts left over when I do things like that.

Boxer,
I had the same dilemna and unfortunately all the tb synch guides blow past this critical issue. Al is right when you twist the throttle and let it go you should hear the metalic clank of the throttle body plates striking the stop screws. Unfortunately if there is some lack of slack in the throttle cable, you will still hear that sound. So that is not a real indicator of whether or not your main throttle cable is within tolerances.
Try this, slacken your main cable as well as your fast idle cables at the handlebars. When you're sure none of them is pulling on the throttles, do your synch at idle and then @ 3500 rpm. This will synch the butterflies independent of the main cable and fast idle. Once thats done, tighten at the handlebars both cables to remove slack. I believe the tolerance for each is one millimeter.
Hope this helps,

Gene

Boxer,

Don't know if this will help, but this write-up from the Adventure Rider forum seems very detailed on the process and may answer your question.

http://advwisdom.hogranch.com/Wisdom/

Scroll down to the bottom and open the link to a pdf titled :

TBSD (Oilhead Throttle Body Synching for Dummies)

Don't know if this will help, but this write-up from the Adventure Rider forum seems very detailed on the process and may answer your question

I've read through that PDF several times and yesterday pored over it again. The biggest difference in those directions and others is they suggest strapping the TwinMax to the tank, as Al did above, and riding along at speed, then stopping periodically to do micro-adjustments to the TBs. I've got all that. They still don't address the issue of the proper play in the cables...At the TBs and at the grips...and their relationships.

Maybe this is something that is considered so simple that it should be understood. I just would like for someone who has had those cables out and replaced them to explain how they connect and the relationship of play at the throttle/high-idle grips and the cable at the TBs.

OK Boxer.....

There are 4 cables coming into the junction box under the battery. The throttle cable and the "choke cable" operate on the top pulley, which itself is attached to a lower pulley which holds the left and right throttle cables.

One wants some slack on the throttle to insure that there is no tension on the TB cables, hence keeping the buterflies open. I think the spec calls fo ~1/8" of angular rotation.......look, as long as the is some celarance on he throttle you are OK.

You also don't want to tighten the cable adjustments at the TB's so that the cables are in tension, not allowing the buterflies to return to their home or closed position. The spec calls for about 1 mm of clearance, they way I check for this is pull on the sheath (the cover of the cable) at the point where it contacts the adjustment in the TB, if you can lift the sheath a little bit you have sufficient clearance.

You will never run out of adjustment, the adjustment to sync the TB's is minute.....if you have to turn the adjustment screw more than 1/4 turn you are doing something wrong.....sometimes just the tightening of the locknut will send the sync out of whack.

With these procedures it is far easier to show you than to write how to do it.....

Actually, I'm more concerned about how you are using the TwinMax, zero and span adjustment, than the iddle and TB sync procedure.......

I thought your bike was one of the ones that Robbie and I collaborated and did the idle and TB sync at the Beakster Bash II, maybe I'm wrong.

Al! You're confusing curiosity with ineptitude. That's okay, they look a lot alike. Just because I want to know what Dawn dishwashing detergent will do to my car's finish, doesn't mean I don't know how to wash my car.

Back at the Bash I was out riding when you guys were fiddling with the TBs....No wait! Maybe I was sleeping...Can't remember for sure. That's what happens when you get old. Like Ronald Reagan..."I just don't recall that happening."

Anyway. After that great post above about cable free-play I have an additional puzzling question that inquiring minds want to know. Or maybe just my "curious" mind wants to know.

Question: If you can gain free play at the TB by adjusting the throttle and "choke" cables, why do we have to also make sure we don't adjust the cable down at the TB too tight? Why not just fix it all at the throttle and "choke" location?

Okay, I can't count either. That was 2 questions.

Oh, and you're right to be concerned about me using the TwinMax. That damn needle bounces all over everywhere. If I turn the adjustment one way, it bounces back and forth to the right of zero. Then I turn it another way and it bounces back and forth to the left of zero. I'm talking MAXIMUM sensitivity here. With my plastic tubing contraption, I could see easily when one side was pulling more air than the other.

Boxer,

When you're adjusting with the twinmax on highest sensitivity you want the needle to oscillate evenly to the left and right of the zero mark.

If square brackets represent full left and full right needle oscillation and the vertical bar represents the zero mark it looks like this when your sync is balanced:

] | [

and not this:

]| [

or this:

] |[


that's where my experience ends.

Boxermania's description gives me a mental picture of two cable segments joined at the junction box you mentioned. I suspect the throttle bodies are buffered from cable slack at the throttle end by that junction box. In other words you could have slack at the handle bar ends but it doesn't affect the lower cable segment because the lower cable segment(s) don't operate until the slack is taken up by twisting the throttle or using the fast idle lever. But, I am woefully underqualified to be making any sort of statement about such things.





DSKYZD

Have you read the article from the MOA magazine? I think it was published around April or June. From glancing at the TBSD, it appears to be about the same. I had planned to work on mine last week, but it was too nice to work, so I rode instead.

2wheelin-Thanks! It was the September '05 issue and I just read it. It pretty much explains what I needed to know, but still does not address the connection between the throttle cables and the 2 TB cables.

This is a great article BTW, for those about to do this with the TwinMax. Is sure clears up some mud for me. I can't wait til this dreaded cold wet cloudy weather passes so I can play with it some more.

Boxer.....The last time I had the mechanism open was last January.....and I don't remember that well. I do know that the "choke" and throttle cable act upon the same mechanism which in itself acts upon a secondary mechanism that pulls on the TB "Bowden cables"

What might be hard for you to visualize is that all of these cables have to be relaxed, read, have a slight losenes at the home position, to insure that no cable is pulling on the TB butterflies. That being said you need some slack on the cable from the throttle to the intermediate pulley, as well as some slack from the secondary pulley to the TB's. The important thing is that when the throttle is rotated the butterflies open at unison.

To hopefully bring closure to your questions all the mechanisms have a stop at the fully open and at the fully closed position. If you can visualize with me for a moment the action of closed throttle and full throttle you could see that we want to have the throttle open the butterflies fully and allow them to close fully.

I have enclosed a diagram of all the cables, hopefully it will assit you, unfortunately the operating mechansm is not shown....you will have to trust me on that one........

http://r1150r.smugmug.com/photos/50913292-L.jpg

Can we stop for a bit, look at the bike and have a brewski with a latte chaser......

Thanks Al! Hmmummm...The latte was fine.

When I saw your diagram, I remembered the parts fiche at MAXBMW and found the same drawing there. Upon enlargement (most things seem to be more impressive upon enlargement) I found it to be very instructive.

As you say, they don't show the inner workings of the box, but I can imagine that. Your description of the looseness required at both ends also gives me a better mental picture of the system.

Maybe one of these days my new neighbor Robbie and I can dive into one of these things and replace some cables to see how it all joins together. I would do it alone, but as I stated before I would still need someone to tell me where the left-over parts belong.

In the meantime, I'll have some more fun with my new TwinMax toy and fine tune those cables. Full reports and pics will follow as always...

Now for another latte. Care to join me?

Oaky! Latest and greatest update on the TwinMax saga.

Had a really nice day yesterday so I rushed home and took the bike out for a spin to warm her up. After returning, I got my handy dandy 10mm wrench and screwdriver ready again. I attached the TwinMax and checked the cables tension at the TBs. HOLY CRAP! They were too tight. Didn't really check them closely before. Then I took out the BBBASs and cleaned them off good. Man were they ever black and grundgy! Another possible cause of the synch problems. Replaced BBBASs and got them about 2 turns out each to start.

Got the idle part synched but looked up to see the idle at closer to 1600! Turned them back in to closer to 1 turn out of seat position and synched. Now they are still about 1/4 turn difference but not as far out as before.

Turned everything off and reread the instructions for up-throttle synch in the September ON magazine. The guy there suggested using 4,000 rpms as an upthrottle place to synch at. My Throttlemeister refused to hold steady at 4k. It continually drifted back down. So I settled for around 2500 to 3000. Finally got it all synched and noticed a loud knocking noise! The bike was really hot by this time so I unhooked everything and took her out for another spin. The loud knocking just stopped suddenly when the bike got some cooling air.

I didn't let it run in the high throttle for very long. It was easy to get the synch right, but I guess with my tinkering with the Throttlemeister I let it get too hot trying to keep it at 4K. The headers never glowed!

But the ride was amazing. The difference is noticeable but now I'm worried about that knocking when the bike got really hot. Any speculations on the cause of that? I have the new left tensioner installed and normally it is much quieter than before, but when that baby got hot it was a very noticeable knocking. Not just the fuel injector tapping! A definite knocking from inside somewhere. But as soon as I started riding and got cooler air over it, it just stopped.

Boxer, you've read the manuals, so I'm not going to go into the basics... After doing numerous TB synchs, I've come up with a way to get the best synch possible every time with no throttle slop. It will take a little longer the first time, but the majority of the work can be done with the engine turned off and the results are worth it!

1. Look at the adjusters on each TB and at your hand grip for regular throttle and your fast idle lever. Your TBs should be set to approximately the same point (ie, you should NOT have one all the way in and the other all the way out). As you indicated, after several adjustments, they will get out of wack. If they're out of wack or either of the hand grip adjustment is more than 3/4's of the way in or out, skip to step 4. If the adjusters look good, proceed to step 2.

2. With the engine off, open the throttle at the hand grip quickly to WOT and you should simultaneously hear two distinct clicks from the throttle stops on each TB. When you fully close the throttle, you should also hear two distinct simultaneous clicks. If you hear the clicks simultaneously at both points proceed to step 3. *Hint, if you're having trouble hearing the clicks, hold open one of the TB's and listen for the opposite TB while you turn the grip. Then switch and do the other side. Then do them together, and make sure they're in synch. Do it several times. If you don't hear the clicks, or the clicks are out of synch, proceed to step 4.

3. It's time to check slop in your throttle. The adjuster at the hand grip will take slop out of both throttle bodies, so it's important that you don't make any adjustments to the hand lever until you know your TBs are at a good starting point. Start by loosening the adjuster for the fast idle lever and loosen the cable a few turns, so that you know that the fast idle lever isn't binding or interfering with regular throttle. Now, use the adjuster at the hand grip to tighten the throttle cable while repeating the click test described above. Adjust until you no longer hear the clicks when you close the throttle. Slowly back out until the clicks return. As soon as the clicks return, you've gotten all slop out of the system, and you can tighten down the lock nut. Now, set the fast idle lever on the first raised setting. Tighten the adjuster cable for the fast idle, while performing the click test. The goal here is to get the cable tightened to a point just above where you no longer hear the clicks when closing the throttle. Once you're there, lower the lever and check for normal operation. If all is good, you're done with this step. Do not tighten the lock nut, as you will make minor adjustments with the engine running later. This concludes the pre-start up procedure. If you made it here, skip to step 5 and prepare to start your engine! (ie gather a fan if you haven't gotten to the point where you can make adjustments using the twinmax in under 10 mins for the entire process)

4. Something is awry, or you wouldn't be at step 4. Loosen all four of the adjusters mentioned in step 1 (two at the hand grip and one on each TB). Start with the TB's and adjust them to a point where they are about equal. Now check the throttle using the click test described above. You will probably have to do one TB at a time, since they will be pretty far out of synch. Concentrate on the decel click, since you haven't taken slop out of the setup yet. Once you get simultaneous decel clicks, you can take some of the slop out, using the main throtte adjuster. Afterwards, a click test should get you to the end of step 1 with 2 simultaneous clicks on accel and 2 simultaneous clicks on decel. Fine tuning (what you can hear)in terms of "simultaneous" will get you to a point where you'll be able to adjust out any differences with the TwinMax. Go back to step 2 and proceed.

5. Any of the basic guides will take you to this point as a starting reference. Work from the right side only when using the TwinMax. Otherwise, you may need to repeat the steps above. Always start by resetting the Motronic ECU by pulling fuse #5 for 30 secs or so. Turn the accessory key on and turn the hand grip smoothly from fully closed to fully open several times to reset the memory settings. Start your bike up and bring it to operating temperature. If you made major adjustments, I would probably let it idle versus riding it. Otherwise, if the changes were minor, I'd probably take it for a 15min. ride. Once it's warm, start with the idle by adjusting the BBAS. Next, dial in your Fast Idle. Finally, finish with a traditional TB synch. You should be able to get it dialed to a point where there is never any more than one bar variance on the TwinMax throughout the throttle range.

Let me know if you have questions... or I see your in North Georgia. If you're anywhere near Alpharetta, I'd be more than willing to check it out for you and walk you through the procedure.

Craig

Boxer....I'm glad that you are closer to understanding what goes on. Once you can picture in your mind what takes place everything becomes very easy to understand.

Regarding the "knocking"....not haven't listened to the noise it would be like guessing how many hairs you have on your back......

Could it have been valves tapping?....the boxers when they get hot the first thing that makes noise are the valves taping because the aluminum of the head which hold the rocker arms expands more than the steel at the valve and th rocker arm, therefore increasing the valve lash.

So at this point I'm at a loss.....however the fact tat as you started the ride it dissapeared is a good sign. I limit myself to a 5 minute run while the bike is on the stand. If I had to run more, I would set up two fans,borrowed from the wife, to blow at the jugs......but this is very seldom an ocurrence.

Last but not east, it is definitely no fun to get to the throttle cables, let along replace them. I'm ever so happy to have done away with the air box......everything is so handy. I can even use a Unysin on my TB's, which truly measures flow through the TB......do you know what a Unisyn is and where was it originally used? That's a test question......

Hey, how far is Robbie from you?....have you visited with him? isn he truly retired, knowing him and his passion, he has to be doing something.

Boxer, I was wondering exactly what you did for the high rpm sync that made your process a success. I did mine yesterday and had the idle sync dead on and the high rpm off by only a smidgen. Of course, couldn’t leave well enough alone and started an on the road micro adjustment journey to nowhere. I was only adjusting the right side a little (1/8-1/4 turn) at a time. Eventually, it didn’t seem to affect the high rpm but it would alter the idle sync. I suspect maybe the outer sheath was messing with my adjustments. More than likely, many of these so called adjustment didn’t even take place because of the PIA nature of the adjuster screw and lock nut arranement. The bike was running well and idling correctly so I gave up for the time being. This morning, my fast idle lever did essentially nothing. I assume when I was trying to correct some of my mess yesterday, I put some slack in the line. Anyway, I’ve probably read all threads from all forums and have ideas what could be wrong but I don’t want/need to make this into a major production since none of it was that far out to begin with. Thus, interested in your outcome since much of your original issues where the same as mine. Thanks.

I eventually had to loosen the cable on both throttle bodies. The left one (the control side) was too tight and wasn't seating all the way. After I loosened both and then adjusted the tension in the throttle cables at both grips, I had to get the extra slack out of each evenly. This I just worked on manually, listening to each as the butterfly inside tapped the bottom. After getting them fairly close and with ample slackness, but not too loose, I put the TwinMax on it and did a synch per the directions using the left side again as the control side and only adjusted the right side to synchronize them.

I now have it running smooth, but I HAVE noticed my high idle switch is still slightly loose and needs some tweaking. It works okay for a cold start, but if I leave it on, my idle will only go up to about 1300rpms. It used to be higher at about 1500 or 1600 rpms after it was warm. Oh well, I really need new cables anyway soon. I can feel the stiffness in the throttle.

Did that help?

Thanks. That definitely clarified things. My left side is visually tighter than the right. Not sure if the dealer did this when I use to take it to them for service or it’s always been different. I was a little nervous about monkeying around with these cables until I now realize it’s merely mechanical linkage. Did you basically follow cmack’s procedure?

Not to hijack much, but on the subject of throttle cable stiffness, I'd encourage you all to consider grip covers. With a little help from liquid dish soap these slide over your existing grips, making them fatter and giving you more leverage on the throttle. I got my set of six grip covers from Grip-Tek for $15 plus shipping. The model I got for my 2003 R1150R was "GCM 4.25 fits bar sizes 1.25" to 1.45", the one in the middle of the page. Less wrist fatigue, more comfortable grip, and they don't even affect the heated grips much at all.