[SuperDave]

Honda refers to the fuel injection throttle body synchronizing as Starter Valve Synchronization. Basically the purpose is to adjust throttle valve for fuel injection throats so that they pass as much fuel-air mixure as all the others (balancing the load by each piston). This balance will affect the response, smoothness, mileage, performance and running temperature of the engine.

I purchased Morgan's Carbtune II (4 column mechanical manometer). The scale is in cmHg (centimeters of mercury). The actual cmHg readings are not as critical as is the synchronizing of throttle bodies #2, #3, and #4 TO #1 ( #1's starter valve is fixed/non-adjustable). I also purchased Snap-On's TM-64 adjustment tool (recommended by member who first started the thread of Starter Valve Synch, DanDRR? Sorry can't remember who, maybe he'll chime in).

So. if anyone's interested, here's my details of how I did my spark plug replacement and Starter Valve Synchronization.

1. Set bike up on rear stand (optional)

2. Remove seat

3. Remove 2 front tank bolts and 1 rear tank bolt

4. Prop the tank up by string method, or I used tie downs extended from open ceiling joist in my basement to hold tank up by the (2) open bolt openings. I also removed the small vent line from under the tank to allow easier/more movement.

5. Remove the (8) screws around the upper airbox and the (2) screws in the middle. A pen light is very handy. Disconnect electrical connector and pull upper airbox cover off.

6. Remove air filter element, and start removing (6) philips head screws of the (2) pairs of velocity stacks. Remove velocity stacks.

7. Pull off (3) hoses on bottom portion of airbox and disconnect another electrical connector. Pull air box up and back to get passed air inlets, now flop the air box over the left side of bike (clutch side) watching for the flapper cable slack. I even used another tie down to support the airbox from above.

8. Pop each spark plug cap, I used leverage from large screwdriver and pryed it up. The plug caps are alot larger than I thought (maybe 4" in length). Pull electrical connection off cap. Remove all (4) caps and plugs, install new plugs, reinstall caps and electrical connectors. Make sure caps are all the way on and secure to spark plug.

Note: Morgan Carbtune recommends that you have everything in perfect working condition and any other work completed before adjusting throttle bodies, ie., new air filter, new plugs, etc.

9. Start removing the (4) vacuum bleed screws from just under the throttle bodies. They are both phillips head and 8mm hex head. Use the best method you can to gaining access to these screws, a magnetic screwdriver would be recommended (I dropped 3 of screws along with 3 of their washers, took awhile to locate and get them out). Flexible screwdriver would be ideal, although you still have to initially break the tight screw/bolt. Note: Also remove the PAIR valve hose at the reed valve and plug the reed valve nipple so to not give false vacuum readings?. Not too bad to get to.

10. Attach the (4) remote hoses for the Carbtune II, the hoses have brass adapters at the end that will thread back into the vacuum bleed locations. Use the hose to guide it to there, and spin the hose to help start threading the adapter (it's freakin tight in there). Make sure #1 bleed screw is #1 hose on Carbtune and so forth.

11. Start the bike and let it warm up to normal temperature, manual recommends using the throttle stop adjustment to raise the idling if necessary to keep bike running at idle and not stalling during synch adjustments. Note: FI light will blink 3 times, then go off, and blink 3 times, etc. This is because of the unplugged electrical connection of upper airbox.

12. After warmed up, document the starting readings of Carbtune. Mine were something like
#1-16cmHg, #2-19cmHg, #3-18.5cmHg, and #4-19.5cmHg.
Use the SnapOn TM-64 tool with a 7mm socket to adjust #2, #3, #4's starter valves to #1's settings. The starter valves are spring loaded and do not have a lock nut to loosen. The Morgan manual states acceptable synchronization is within 2cmHg of each cylinder. I got mine to equal out across the board at 16cmHg (just about perfect).


13. Adjust and wait for reading, gently blip the throttle to set the adjustment. Turn the starter valve clockwise to bring reading down. Adjust until all are equal or close to #1's reading. Turn off bike and reverse procedure.

Done, now throw away all the empty beer bottles!

Let the bike cool down before attempting to remove the Carbtune hoses/adapters, not only will the bike be hot but the adapters will be easier to unthread once cooled.

I have definately felt and heard the difference with my new plugs and synchronizing the starter valves. Idles smoother, crisp response, doesn't seem to vibrate as before - but, I haven't been able to test ride it yet (rain, rain, and more rain). I will reply with opinions of ride afterwards.

Feel free to correct anything I missed or wrong.

Later

[Jake]

Question regarding step #10. I'm having difficulties locating where to hook up the vacuum lines too. Does anyone have a pic to show me or perhaps can help me out with what to look for? I did notice the vacuum lines that go into the "Map Sensor," these are not where to connect to are they? I'm assuming the brass fittings are supposed to be on the back of the throttlebodies? Attatched are a couple of pics, perhaps someone could circle the appropriate location for me?
Thanks!

[Joel]

Jake,

The vacuum lines actually go into the head. There are 4 screws (see pic) very close to where the throttle bodies attach. The screws come out, then the adapters go in their place. Note that there is a torque setting on those screws. I have an inch-ounce torque wrench that I managed to squeeze in there, but if you don't, it's a pretty healthy turn with a screw driver handle.

[ulysses_sc]

i installed the carbtune remote extension hoses permanently to the vacuum holes. now this once tedious procedure has become much easier. really worth spending that few more dollars for those hoses.

i've been propping up the tank and holding it in position with a piece of wood abt a foot long and a string tied to the right frame slider and the tip of the tank to hold it in place. works best with the bike on the sidestand.

the appropriate socket (is it 6 or 7mm? can't remember...) on a short extension works just fine in turing the starter valve.

you can also hang the airbox off the left frame slider (provided it's there and fits...) by slotting it in through one of the holes meant for the velocity stacks. works fine for me!

[SuperDave]

Originally Posted by Jake

Question regarding step #10. I'm having difficulties locating where to hook up the vacuum lines too. Does anyone have a pic to show me or perhaps can help me out with what to look for? I did notice the vacuum lines that go into the "Map Sensor," these are not where to connect to are they? I'm assuming the brass fittings are supposed to be on the back of the throttlebodies? Attatched are a couple of pics, perhaps someone could circle the appropriate location for me?
Thanks!

What Joel said. Also, the brass fittings I was referring to fit on the end of the rubber hoses supplied with your Carbtune guage. They thread into where you removed the vacuum screws (see Joel's pic) and the other end obviously goes on the Carbtune guage. Take a flashlight and look just under the throttle bodies. It's going to look impossible to get to, but you can. Remove your mid fairings and you'll see where you can fit your hand in there. Good luck!

[SuperDave]

Originally Posted by ulysses_sc

i installed the carbtune remote extension hoses permanently to the vacuum holes. now this once tedious procedure has become much easier. really worth spending that few more dollars for those hoses.

I thought about doing this, never did. What did you plug the hoses with and where did you store or tie up the hoses?

[Fire929blade]

Very useful post SuperDave I'm planning on doing the starter valve synch in the near future, but I'll have to buy one of those Carbtune tools first.

I checked the valve clearances last night, and everything was spot on after 24000 kilometers The plugs i put inn at 12000 km's still look like new to..

[SuperDave]

Originally Posted by Fire929blade

Very useful post SuperDave I'm planning on doing the starter valve synch in the near future, but I'll have to buy one of those Carbtune tools first.

I checked the valve clearances last night, and everything was spot on after 24000 kilometers The plugs i put inn at 12000 km's still look like new to..

Thanks dude! I'm still going to take the bike to the dealer for the valve clearance check. I don't have the feeler guages and I'm just a little intimidated with the cam area. We'll see, maybe I'll give it a shot, Joel (I think) had an awesome write up on that check.

[Joel]

http://www.fireblades.org/forums/sho...ighlight=valve
or
http://mywebpages.comcast.net/joelco..._clearance.htm

[Jake]

Joel and SuperDave,
Thanks for all the help! I kept looking and looking and would find nothing, now I know why.

[Frog4aday]

Hey Super Dave,
Thanks for posting your write up on the Throttle Body Synchro for the CBR929RR! I am about to undertake this project myself and have read the factory service manual but still didn't feel completely comfortable with the amount of info provided by that source. You're write up filled in some 'blanks' for me and have given me a bit more confidence to do the job right. I know it takes a lot of time to take pictures, do the writing, and get something like this posted to benefit all. I just wanted to say thanks again for doing it. Sincerely,
Pat Coleman (CBR929RR, "the big bee", @40,000 mi. & still going strong!)

[EatnAsphalt]

Great write up! I'll be doing this for the first time on my 929 soon. 48k miles and still runs fine but I figure it's probably due.

I am getting ready to buy the appropiate tools for this job and have a question about Snap-On's TM-64 adjustment tool. From their description is it a rigid tool. Have you looked at TM-65? It is the same except flexible.

Would the flexible one make it easier or is the rigid one easy enough to use? From other threads I know with my Cali bike I will need to remove the canister. I'm wondering if using the flexible Snap on tool would keep from having to remove the canister.

[Joel]

Originally Posted by EatnAsphalt

Would the flexible one make it easier or is the rigid one easy enough to use? From other threads I know with my Cali bike I will need to remove the canister. I'm wondering if using the flexible Snap on tool would keep from having to remove the canister.

I highly doubt it.

I'm happy with the rigid tool.

[EatnAsphalt]

Originally Posted by Joel

I highly doubt it.

I'm happy with the rigid tool.

Great. I'll pick one up!

[Frog4aday]

I did the starter valve synchro (throttle body synchro) on Saturday and took the bike out for a ride today. The bike was smoother, especially off idle, and it is not nearly as "abrupt" when rolling on the gas from a closed throttle position now. That's a huge plus in my book!

All my throttle bodies were within 2 mm Hg of each other (w/in spec?) when I started, so I didn't really expect to feel any big change from doing the job, but by getting them all as close to perfect as I could, it ended up making a significant difference in smoothness and ridability.

But it's a PIA! I don't want to go through doing this procedure again any time soon. Lots of stuff had to come off the bike to get to the right parts and getting the vacuum nipples installed on the throttle bodies was a pain (wished I had the arms of a skinny 8 year old at the time!) But now that it's all done - and the bike is buttoned back up and running smooth - I'm glad I did it. Thanks again Super Dave.
Pat (CBR929RR, "the big bee")

[SuperDave]

Hey, this thread is still alive? LOL

I'm glad my little write up helped Pat!

You're right about needing those small hands. I've done this procedure several times (I'm anal that way ). I actually have the certain hand/arm angles down now, ie. contortionist (sp?).

About the only thing I questioned was 1. whether to leave the velocity stacks and air filter on for more realistic enviroment while tuning and 2. exactly how much of a "blip" to give it to reset the tool. If you give it too much it seems to change the readings.

Again, thanks and I'm glad it helped!

[DG rider]

OK, i did this ( IAC sync ) today on my CBR1000RR. Here's the dirt...

First off, from the sound of the first post, the CBR1000RR is a bit more involved for doing this.

The basic procedure is the same except for the following notes:

1) Remove the faring top shelter, lowers and mid's.

2) To block the PAIR ports on the 1000rr you will have to remove the front portion of the ram-air duct ( the air box stays in place ), which involves unplugging the fan motor, moving the radiator down ( no need to drain the coolant ), removing the screen from the front of the duct, remove the two front bolts in the duct, and then the two screws visible from between the frame spars.

Next, unplug the camshaft position sensor, and vacuum hose from the flap in the ram-air duct. After doing that, you will need to "rock" the air box back ( from the bit of give in the rubber intake manifolds ) slightly to release an upper tab from the front-to-mid duct, then pull the duct forward between the fork legs. It's tight, but with a bit of work, you can remove the duct this way. Once here, you can block the PAIR ports.
Be sure to temporarily re-install the cam sensor, fan motor plug, and move everything off the headers when running the engine.

Basically, this is following the procedure for gaining access to the plugs in the factory service manual. If you don't have one, don't even think of trying this. This is the reason i have been a bit vague in my directions. These instructions go for plugging the PAIR valve ONLY. If you wish to remove and block this stuff permanently, you will have to remove the air-box to get to the PAIR control solenoid.

On several boards, i have ask why you simply couldn't plug the PAIR suction hose at the air-box ( which would have the same effect ), or unplug the PAIR control valve, but have yet to get a satisfactory response.

3) Once you prop the gas tank up and remove the rubber "Diapers", you can access the vacuum lines for each throttle body. The 1000RR already has lines running to the MAP sensor ( mounted about mid-air box, slightly off-set to the right ). There is a 5-way tee with one line to the sensor, and the four for the Throttle Bodies. Unplug the four lines running to the TB's and hook them to your gauges ( the MAP line is simply left un-plugged for this ). You will note that the engine will idle very low for a few seconds until the MIL lamp starts flashing ( from the MAP sensor being unplugged ), then it will seem to speed up and idle normally.

The IAC valves on the 1000RR take a 7MM socket ( strange, but true ) for numbers 3 and 4. Number 2 takes a larger socket or a blade type screw-driver, but i found that it would be impossible to get a socket to it, so i used a screw driver. Once again, #1 is the base and cannot be adjusted.

Once warmed up, i noticed the the levels fluctuated a bit between cylinders, but i was using the mercury style gauges....and to be honest, you have to expect a 998cc engine making 150 RWHP ( and the cam profiles that go with this ) to do this to some degree. You may also notice that simply touching the valve might cause a small change ( my #2 did this ). For this reason, make your adjustment, and them remove the socket/screwdriver.

Set each level to match #1 a closely as possible, but don't expect to get them perfect on this bike. Allow the bike to run for several seconds between adjustments for the levels to stabilize before making more. Once you have them where you want them, blip the throttle, and make sure they stay approximately the same. Again, allow several seconds for them to stabilize before passing judgment. I found that blipping mine did little to change the vacuum levels between cylinders.

Once your satisfied, remove the gauges and reverse the steps to button things back up. Once you reconnect the MAP sensor, the MIL light will stay off when the bike is restarted.

Again, all of this is in the manual, and don't try this without it.

In retrospect, i think i would spend the money for the mechanical gauges that Superdave used, if for no other reason than avoiding contact with mercury ( BAD, BAD stuff!!! ). I used a Motion-pro "econo" carb-tuner. It works, but it shows it's "econo" status in some respects.

Removing the air-duct on this bike is a bit of a PITA, and were it not for this, sync'ing the throttle bodies on this bike would be a breeze. I would understand if you wanted to completely remove the PAIR stuff just to skip that step, but i like to think of the environment.

Hope this helps!

[kc954]

just did this on my 954 last night. The procedure was very similiar to that of the 1000RR with the exception of all the work necessary to get to the pair system. Made a drastic improvement in my bike, its like new!

[cedric1050]

Originally Posted by SuperDave

Honda refers to the fuel injection throttle body synchronizing as Starter Valve Synchronization. Basically the purpose is to adjust throttle valve for fuel injection throats so that they pass as much fuel-air mixure as all the others (balancing the load by each piston). This balance will affect the response, smoothness, mileage, performance and running temperature of the engine.

I purchased Morgan's Carbtune II (4 column mechanical manometer). The scale is in cmHg (centimeters of mercury). The actual cmHg readings are not as critical as is the synchronizing of throttle bodies #2, #3, and #4 TO #1 ( #1's starter valve is fixed/non-adjustable). I also purchased Snap-On's TM-64 adjustment tool (recommended by member who first started the thread of Starter Valve Synch, DanDRR? Sorry can't remember who, maybe he'll chime in).

So. if anyone's interested, here's my details of how I did my spark plug replacement and Starter Valve Synchronization.

1. Set bike up on rear stand (optional)

2. Remove seat

3. Remove 2 front tank bolts and 1 rear tank bolt

4. Prop the tank up by string method, or I used tie downs extended from open ceiling joist in my basement to hold tank up by the (2) open bolt openings. I also removed the small vent line from under the tank to allow easier/more movement.

5. Remove the (8) screws around the upper airbox and the (2) screws in the middle. A pen light is very handy. Disconnect electrical connector and pull upper airbox cover off.

6. Remove air filter element, and start removing (6) philips head screws of the (2) pairs of velocity stacks. Remove velocity stacks.

7. Pull off (3) hoses on bottom portion of airbox and disconnect another electrical connector. Pull air box up and back to get passed air inlets, now flop the air box over the left side of bike (clutch side) watching for the flapper cable slack. I even used another tie down to support the airbox from above.

8. Pop each spark plug cap, I used leverage from large screwdriver and pryed it up. The plug caps are alot larger than I thought (maybe 4" in length). Pull electrical connection off cap. Remove all (4) caps and plugs, install new plugs, reinstall caps and electrical connectors. Make sure caps are all the way on and secure to spark plug.

Note: Morgan Carbtune recommends that you have everything in perfect working condition and any other work completed before adjusting throttle bodies, ie., new air filter, new plugs, etc.

9. Start removing the (4) vacuum bleed screws from just under the throttle bodies. They are both phillips head and 8mm hex head. Use the best method you can to gaining access to these screws, a magnetic screwdriver would be recommended (I dropped 3 of screws along with 3 of their washers, took awhile to locate and get them out). Flexible screwdriver would be ideal, although you still have to initially break the tight screw/bolt. Note: Also remove the PAIR valve hose at the reed valve and plug the reed valve nipple so to not give false vacuum readings?. Not too bad to get to.

10. Attach the (4) remote hoses for the Carbtune II, the hoses have brass adapters at the end that will thread back into the vacuum bleed locations. Use the hose to guide it to there, and spin the hose to help start threading the adapter (it's freakin tight in there). Make sure #1 bleed screw is #1 hose on Carbtune and so forth.

11. Start the bike and let it warm up to normal temperature, manual recommends using the throttle stop adjustment to raise the idling if necessary to keep bike running at idle and not stalling during synch adjustments. Note: FI light will blink 3 times, then go off, and blink 3 times, etc. This is because of the unplugged electrical connection of upper airbox.

12. After warmed up, document the starting readings of Carbtune. Mine were something like
#1-16cmHg, #2-19cmHg, #3-18.5cmHg, and #4-19.5cmHg.
Use the SnapOn TM-64 tool with a 7mm socket to adjust #2, #3, #4's starter valves to #1's settings. The starter valves are spring loaded and do not have a lock nut to loosen. The Morgan manual states acceptable synchronization is within 2cmHg of each cylinder. I got mine to equal out across the board at 16cmHg (just about perfect).


13. Adjust and wait for reading, gently blip the throttle to set the adjustment. Turn the starter valve clockwise to bring reading down. Adjust until all are equal or close to #1's reading. Turn off bike and reverse procedure.

Done, now throw away all the empty beer bottles!

Let the bike cool down before attempting to remove the Carbtune hoses/adapters, not only will the bike be hot but the adapters will be easier to unthread once cooled.

I have definately felt and heard the difference with my new plugs and synchronizing the starter valves. Idles smoother, crisp response, doesn't seem to vibrate as before - but, I haven't been able to test ride it yet (rain, rain, and more rain). I will reply with opinions of ride afterwards.

Feel free to correct anything I missed or wrong.

Later

I have a problem starting my bike in the morning could this be my problem. i have to jump start my bike with start fluid in the morning after that it will run all day.

[Frog4aday]

Originally Posted by cedric1050

I have a problem starting my bike in the morning could this be my problem. i have to jump start my bike with start fluid in the morning after that it will run all day.

--------
I'm thinking a TBS is not what you need to solve your issue.
I think you would want to look at the cold start doohicky. For the life of me, I can't think of the name now, but as I understand it, it's a waxed filled thing and it tells the bike "you're cold" so the FI knows to give it more gas. Then when the wax gets warm and melts, it tells the bike "You're warm" so it adjusts the FI accordingly.

I've read on the VFR list that this thing can go bad at times. Get a new one and all is right at cold start time again. (Sorry I can't think of the name right now...)
Pat in Monument, CO

[cedric1050]

Their are three holes hooked to the bottom of the tank, does anyone of these holes connect to the cold air doohicky?

[cedric1050]

can you tell me were the 3 hoses on the bottom of the tank connect to on the motor. i took the tank and hose off for paint and now i forgot were the 2 little hoses connect to as far as the motor. in other word can you tell me what hose connect to the motor.