first throttle body sync help

riceburner · Post by **riceburner** » Mon Jul 30, 2007 7:23 am

MikeCam wrote:BBAS initial setting and adjustment.

1. Keeping count, fully seat the BBAS. Then back off 1.5 turns. Both sides even.

2. At warm idle, with manomometer attached, seek the 1050-1100rpm idle level while keeping both screws aligned equally in their relative position to 12 o'clock and each side of the manomometer equal.

3. When you are finished, both screws should be symetrically aligned and idle should be between 1050-1100 rpm.

First time I tried this the TBs were SOOO out of synch AFTER point 1 I nearly fed all the oil in the manometer into one of them.

I had to wind the BBAS on the left about 3 turns out to get them to equalise - Mike - could you comment on this?

Post by **MikeCam** » Mon Jul 30, 2007 8:43 am

Comment number 1 - Rob knows more than me.

Comment number 2 - I'd almost suspect a vacuum leak if one BBAS is more than one turn different from the other.

Comment number 3 - If the right side cable is still under tension, that could explain a difference in BBAS settings. If the left side cable prevents the butterfly from touching the stop, that could explain a difference in BBAS settings.

Added later after reflection....maybe one sides' BBAS was all the way in and the other was all the way out? Then the initial settings would be way off.

Post by **GypsyRR** » Mon Jul 30, 2007 9:51 am

I'm trying to follow this thread, but it has my head spinning. There is no way I am going to attempt this without someone coaching me through it.

I'm requesting a R1150R.net Tech Day/Weekend .......... and I think I'll start a thread in Off Topic about a concept I have for it.

Good luck, John.

Post by **Dr. Strangelove** » Mon Jul 30, 2007 12:36 pm

TA DA! Done!

ok first---took a ride this am with just the valves adjusted--they were not out much, but as IowaB said: It is a Zen thing so I made them better, and it paid off. The response was much smoother and any surging I might have around 3500 was minimized, or at least much much less.

Next thing I did was find the blue paint throttle stop. Found it...easy to avoid.

a house fan on both cylinder heads and a BA pedestal fan blowing across the field. (It still gets hot down there.)

connect tubing, seated BBAS, unseated by 1.25 turns, pinched tubing, turned engine on, s l o w l y unpinched tubing--can easily see how my atf could be sucked right on up the tubing.

when things settled some minor adjustment of the BBAS leveled things. ATF behaved well, btw, re sensitivity.

now to the higher rpm setting. used my T Meister to hold rpms steady ~~3k. unlocked the locknut (10mm open wrench-longer is better). They are off by about 8". Turn the barrel adjuster with a needle nose pliers, get them even. Locking down the locknut changes things, have to redo. Now I notice that my connecting tubing has warmed up so much that it has collapsed. %#^&!
redo the connecting tubing and reconnect and start from beginning.
Now easier to sync at idle. Bring her up to speed and all is level!
Go back down to idle and we are still level.

I think that means success. I check the operation of the right throttle cable and it looks fine.

So, I did my valves, I did the TB sync and now it's on to an oil change, tranny fluid change and FD oil change and that will be the meat of this 18k service.

Thanks to all for the suggestions and encouragement.
John

Post by **boxermania** » Mon Jul 30, 2007 12:44 pm

Dr. Strangelove

I live in Baton Rouge and will be willing to travel to N.O. and colaborate with you on the finner aspects of 1) idle adjust, 2) TB's sync, 3) Valve adjustment and any other obscure subject matter you care to discuss about your bike. pm me if you are interested.

Gypsy....

Maybe we can put together a video on how to perform these tasks for everyone's benefit. We will have to use your bike as the subject, since I no longer have mine.

I think is time for another review of those items that can be dealt with sucessfully by an owner with average mechanical skills, which in my humble oppinion, adds to the pleasure of riding the bike.

Post by **GypsyRR** » Mon Jul 30, 2007 12:56 pm

Congratulations, John. Where are the photos? Notations?

boxermania wrote:
Gypsy....

Maybe we can put together a video on how to perform these tasks for everyone's benefit. We will have to use your bike as the subject, since I no longer have mine.

I think is time for another review of those items that can be dealt with sucessfully by an owner with average mechanical skills, which in my humble oppinion, adds to the pleasure of riding the bike.

I willingly volunteer my bike for the video production. Maybe this can supplant my ideas in my thread about a Tech day over in Off Topic.

Post by **Dr. Strangelove** » Mon Jul 30, 2007 5:51 pm

hey, Boxermania
thanks for the offer, I'll keep that in mind.

There is a little oily residue at the bottoms of both cylinder heads--truly a little and that may be related to them going back on a little oily. will keep an eye on that. I torqued the cylinder head bolts to 10 nM--the lowest setting on my torque wrench. I know it called for 8, but it's 10.

I am fairly sure the gaskets went on properly, so maybe only a little house-keeping is in order. I did oil them before replacing so maybe that's it.

Sorry, Gypsy, no pics (but, hey, I did contribute a thousand words). there are lots of pics on the web of this procedure and I can post the links, if you want.

What is interesting is that there are lots of basic procedures that any owner can do. They are simple, but clear English and visual aids are necessary. Also, when you're doing the TB sync, things are heating up pretty quickly and one does not have time to take pics--at least I didn't during my first stab at doing it. Next time fa'sure.

And I am up for a tech day video also

John

Post by **ProductUser** » Mon Jul 30, 2007 6:25 pm

There's video on the BMWST site that shows all of the basic maintanance procedures for the 1150RT, which is just like our bikes, but without all of the plastic. It was made by one of the guys on the BMWST site and has received good reviews. This is not a free video, however, the cost is pretty low.

If you're interested in the video, I will find the link and post it.

Disclaimer: I do not receive any royalites from the sale of the videos.

ProductUser

Post by **Boxer** » Mon Jul 30, 2007 7:21 pm

I did oil them before replacing so maybe that's it.

Don't do that next time.
If you examine the smooth inside face of the small rubber gasket that goes inside around the spark plug, you will see where it is indented from resting tightly against the metal 'whatchamacallit'. By turning that gasket slightly from its original position upon re-installation, you will have a slightly better seal.

Post by **Dr. Strangelove** » Mon Jul 30, 2007 7:40 pm

>> If you examine the smooth inside face of the small rubber gasket that goes inside around the spark plug, you will see where it is indented from resting tightly against the metal 'whatchamacallit'. By turning that gasket slightly from its original position upon re-installation, you will have a slightly better seal.<<

I did that, but that is not the gasket I am referring to. I am talking about the big almost rectangular plastic-like gasket that goes between the cyl head covers and the cylinder heads themselves.

There was a little smudge of grease on the right and more-than-a-smudge on the left, at the bottom. I cleaned both well, then went for a ride--I'll check in the am.

Re: the ride---MUCH better. The bike rode nicely before, but now it's " like buttah." So smooth. seems less reluctant to give low end grunt. Even hint of surging is virtually gone. Glad I undertook this endeavor.

Post by **iowabeakster** » Mon Jul 30, 2007 7:42 pm

John (and all interested),

I bring this up becuase of the Throttle Meister.

Did you make the adjustment to the cable with the motor spinning at 3000? If yes... I would reccommend that you:

1. start motor
2. spin the motor (i.e. 3000)
3. look and get your reading on the guage, release throttle
4. turn off motor
5. make ajustment to cable

then reapeat as necssary (Don't go too slow, such that the bike cools)

Even with the fans, doing the fine tuning with the motor spinning (3000), will get it exceptionally hot (this may be the reason for the collapsed tubing). As you found, it takes a couple attempts to "get" it ...just so.

def38 · Post by **def38** » Mon Jul 30, 2007 9:40 pm

In the following order;

1- Adjust valve lash on a stone cold engine. Equal valve to valve lash not absolute lash is important here. If you're off by 0.001" don't worry but, get them equal.
2- Gently seat each large brass idle bleed screw. Record the turns to seat. Then remove them completely...careful...don't mix them. Now, spray the screws with carb cleaner to clean them. Also, spray a bit of carb cleaner into the idle screw port. You'll likely find some fuel residue in there. Don't overdo it with the carb spray. Reinstall the brass screws to their previous settings after lubing the O-ring with a small bit of silicone grease or spray.
3- Ride the bike to full warm (5 bars on the RID).
4- Attach your manometer to the carb stubs.
5- With fans blasting air onto the front of cylinders and oil cooler start the engine and allow it to idle. Observe the idle RPM and adjust one brass screw (I usually adjust only the right side) to achieve equal oil level in the manometer. Adjust the left screw only if RPM is not in spec. This should take about 30-45 seconds.
6- Adjust right throttle cable to provide equal manometer oil level while engine is at 3000-3500 RPM, again, about 30 seconds is all it takes.. Snug the TB grub screw and recheck manometer level at 3000-3500 RPM.
7- You're done. Miller time!

Caution; DO NOT ADJUST THE THROTTLE STOP SCREW SETTING. This is a factory setting and should not be disturbed.

DO NOT ADJUST THE TPS SETTING. This is a factory setting and should not be disturbed.

hirsty · Post by **hirsty** » Tue Jul 31, 2007 7:15 am

I did my adjustment on Friday, but only used the Big Brass Screws - is this okay? They are now slightly out of sync, relative to the closed position, but all seems well.

I was just a quarter-of-a-turn out on the RHS screw, and now it's spot on at idle. Revving the bike up to 3 or 4,000 RPM showed pretty level on my gauge, so I don't need to adjust the cables right now?

Post by **awagnon** » Tue Jul 31, 2007 10:21 am

Revving the bike up to 3 or 4,000 RPM showed pretty level on my gauge, so I don't need to adjust the cables right now?

I think this is the same as checking the balance or synchronization at these RPM's. If the manometer or TwinMax is balanced at those RPM's, then I think you're good to go. Nothing, to adjust.

Post by **Dr. Strangelove** » Tue Jul 31, 2007 10:38 am

IowaB,

I think I did that in a slightly different fashion. I adj the levels at idle.
Then I used the t meister to hold ~~3000 rpms. Adjusted the barrel adjuster so that the left side was slightly higher and almost tightened the locknut

NB--I discovered that the locknut tightening would bring the left side down/right side up no matter how careful I was

The levels at 3000 were then even.

Released the t meister; idle was even. Rolled the throttle back to 3000--w/o t meister--still even.

turned engine off and then went for a ride and enjoyed the fruits of my labor. I have not checked again, but will after a few days, maybe.

It appears you're saying adjust the barrel with the engine off and then restart to check--trial and error approach

It appears there are many subtly different ways to skin this cat

John

def38 · Post by **def38** » Tue Jul 31, 2007 12:30 pm

hirsty wrote:I did my adjustment on Friday, but only used the Big Brass Screws - is this okay? They are now slightly out of sync, relative to the closed position, but all seems well.

I was just a quarter-of-a-turn out on the RHS screw, and now it's spot on at idle. Revving the bike up to 3 or 4,000 RPM showed pretty level on my gauge, so I don't need to adjust the cables right now?

Sounds like you're all set. A small difference (oil level) at moderate throttle will make very little difference in performance...likely not noticable.

What you are really doing is compensating for minor deviations in the idle circuit as the TBs wear as well as cable stretch, which mostly ceases after 2 years.

Also, exhaust system crosstalk between cylinders through the exhaust bridge tube will cause variations in the manometer readings at constant throttle.

Post by **boxermania** » Tue Jul 31, 2007 2:34 pm

def38 is right on with the description of the sync procedure. I would like to expand a bit as to the reason for some of the steps.

Removal and cleaning of the brass idle screws - These screws are fitted with an o-ring, however dirt and debris accumulate above the o-ring and along with the dry-out of the o-ring will make the screws hard to turn (albeit they don't need a lot of turning to adjust).

However more important is that the bottom of the screw is tapered, to regulate the amount of air that bypases the throttle valve (and as such the rpm of the engine). When removing the screw for the first time you will be amazed at the amount of dirt/shadow that has accumulated in the tapered area. I use WD-40 and a rag to clean the screws and a Q-Tip with WD-40 to clean the hole. Do not use sand paper, scotch-brite or anything that could damage the taper.

Sync of the throttle bodies
The reason for cracking the throttle to 2500 to 4000 rpm is to get the throttle valve to move from the rest position. There is a minute amount of air flowing by the TV in the rest position, but not enough to indicate if both TV's are opening at the same time and the same amount. That is why by cracking the throttle open to, say 3000 rpm, so it alows a large flow to get past the TV with no influence from the idle screw.

The sync of the TB is by far more importatnt to the operation of the bike than the balance of the idle speed. The idle speed will make the bike run rough or kill at idle, the TB's, when out of balance will make the bike run like "caca" since one cylinder will be pulling more air than the other and therefore working harder (remember that the amount of fuel injected will be the same for both cylinders). It doesn't make for a pleasant ride.

Two additional comments on this topic:

The adjustment required to bring the TB's in sync is very small and can be easily disturbed by the tightening of the lock nut. So A) if you have to turn the adjustment screw more than 1/4 turn something is wrong. B) Be extremely carefull that you don't overtighten the locking nut because the threads will strip easily.....and the following will apply:

Cost of cable - What is a few bucs for a BMW owner
Replacing the cable - Major dissasembly with a bit of cusin' and libation of your choice to placate the nerves.
What you learned not to do the next time - Priceless......

On a new bike, typically once the cables strech the owner will find that there is hardly any change in the TB sync and the same goes for the iddle speed, although it has nothing to do with cable strech. We just run a quick check on all of our group bikes (5) at the begining of the season.....

Ahhh....I love this site

def38 · Post by **def38** » Tue Jul 31, 2007 2:55 pm

boxermania wrote:def38 is right on with the description of the sync procedure. I would like to expand a bit as to the reason for some of the steps.

Removal and cleaning of the brass idle screws - These screws are fitted with an o-ring, however dirt and debris accumulate above the o-ring and along with the dry-out of the o-ring will make the screws hard to turn (albeit they don't need a lot of turning to adjust).

Thank you for the flowers...your comment about cleaning the brass idle screws brings back some memories of my time in the US Navy.

As you know, brass aboard ship must be polished routinely. Most of us used Brasso (based upon recommendations from the US Marine detachment we had aboard ship).

Well, the last time I had my LBBPSs (brass idle screws) out of the TBs, I removed the O-ring and got out the Brasso. My LBBPSs never looked better...even A US Marine would be proud. Now, I don't recommend to all of you out there to Brasso your idle screws but, if you do, you're following a long tradition which is part USN and part USMC. Semper Fidelis, Anchors aweigh...Brasso on your GS spokes works wonders, as well.

Post by **CycleRob** » Wed Aug 01, 2007 12:07 am

I prefer to leave those two BBAS adjusters alone and take them out for cleaning about once every 3 years. They don't really get "dirty" because they are on the clean side of the air cleaner. They get gummy from dried fuel fog deposits after the motor is shut off. The fuel fog cloud sometimes left in the intake manifold sneaks out thru the air bleed passageway and eventually builds up a film, then after hundreds of times doing that, a gunky deposit. Because of the VERY strong vacuum signal passing thru the BBAS metered orfice, it doesn't really become a problem that must be cleaned away. It's almost self cleaning after a point. You just readjust them a tiny bit and the synch is perfect again.

The first time I took my BBAS out I noticed the fine Aluminum threads in the TB and how they "grated" with that uncomfortable metal-2-metal feeling. That, plus the O-ring was really being traumatized after the dozens of turns thru the female threads. The very fine threads to me look like they were not meant to be removed for cleaning at EVERY service. You have brass in contact with Aluminum without much lube. The little voice in my head is one I always listen too . . . . and it said: "Ut ohh, that doesn't look like it was designed for frequent R&R" I cleaned up the small black gunk, briefly spray cleaned the threaded tunnel's bottom cone and orifice then blew it out with shop air into the inserted rag at WFO (FT). I deemed the rag necessary so the liquid and deposits soaked into the rag and didn't go into the cylinder. Then I greased the BBAS threads and O-ring with wheel bearing grease and put them back in.

More important, I think, is cleaning the TB throttle valve perimeter and it's matching metering area with an old toothbrush and Gumout Carb-Clean. For that you have to loosen and retract the intake tubes into the airbox and partially remove the TB so a rag barrier can catch all the cleaning spray. Deposits in the throttle metering area will cause crazy, uneven, non-linear responses when you try to do your "on throttle" synch. Holding the throttle WFO is necessary for a thorough cleaning.

BTW, What does the service manual say about the frequency of cleaning the BBAS? (I swear I didn't peek!)
Mine are due for R&R with a cleaning at the next service (60,000 miles). that'll be their 2nd time removed. At the rate I'm not riding lately that could be next year.
I'll wait.

def38 · Post by **def38** » Wed Aug 01, 2007 8:12 am

CycleRob wrote:I prefer to leave those two BBAS adjusters alone and take them out for cleaning about once every 3 years. They don't really get "dirty" because they are on the clean side of the air cleaner. They get gummy from dried fuel fog deposits after the motor is shut off. The fuel fog cloud sometimes left in the intake manifold sneaks out thru the air bleed passageway and eventually builds up a film, then after hundreds of times doing that, a gunky deposit. Because of the VERY strong vacuum signal passing thru the BBAS metered orfice, it doesn't really become a problem that must be cleaned away. It's almost self cleaning after a point. You just readjust them a tiny bit and the synch is perfect again.

The first time I took my BBAS out I noticed the fine Aluminum threads in the TB and how they "grated" with that uncomfortable metal-2-metal feeling. That, plus the O-ring was really being traumatized after the dozens of turns thru the female threads. The very fine threads to me look like they were not meant to be removed for cleaning at EVERY service. You have brass in contact with Aluminum without much lube. The little voice in my head is one I always listen too . . . . and it said: "Ut ohh, that doesn't look like it was designed for frequent R&R" I cleaned up the small black gunk, briefly spray cleaned the threaded tunnel's bottom cone and orifice then blew it out with shop air into the inserted rag at WFO (FT). I deemed the rag necessary so the liquid and deposits soaked into the rag and didn't go into the cylinder. Then I greased the BBAS threads and O-ring with wheel bearing grease and put them back in.

More important, I think, is cleaning the TB throttle valve perimeter and it's matching metering area with an old toothbrush and Gumout Carb-Clean. For that you have to loosen and retract the intake tubes into the airbox and partially remove the TB so a rag barrier can catch all the cleaning spray. Deposits in the throttle metering area will cause crazy, uneven, non-linear responses when you try to do your "on throttle" synch. Holding the throttle WFO is necessary for a thorough cleaning.

BTW, What does the service manual say about the frequency of cleaning the BBAS? (I swear I didn't peek!)
Mine are due for R&R with a cleaning at the next service (60,000 miles). that'll be their 2nd time removed. At the rate I'm not riding lately that could be next year.
I'll wait.

Good practice. Your description of the residue that collects at the LBBPSs and ports is correct...fuel vapor residue. I commute daily to work and as such, my engine is started, warmed and cooled twice daily. Also, I live in a humid environment, Houston. These two circumstances give rise to promoting deposits at the idle circuits in the TBs...hence my cleaning from time to time. Also, I like to renew the O-rings in the intake tracks. In fact, I completely remove both TBs about every 10,000 miles and thoroughly clean them. This is necessary to remove the deposits that collect at the throttle plate-air horn interface. Also, one can peek into the intake port and check intake valve deposits...kind of like looking down your throat..."say Ahhhhhhhhhh"

Of course, the use of Brasso is strictly optional and the aforementioned polishing of the LBBPSs should be performed only by a retired sailor or marine, preferably one who has shipboard experience and has served at sea.

As for the service manual, there is no maintenance recommendation regarding servicing of the TBs...and no mention of polishing the LBBPSs....pity!