Insight on synchronizing throttle bodies?

[Tailgate]

Yamaha service manual refers to "vacuum gauge carb synchronizer (YU-44456)" to sync the throttle bodies. I'm trying to find one--I'm a do-it-your selfer (purchased the 2007 FZ-6 service manual) and don't mind learning a new procedure. My last bike had carbs. FI is all new to me.

Is there a comparable tool that performs the same job? Sombody mentioned a "motion pro carb stick" in an earlier post. Anybody have tips on synching the throttle bodies on an 2007? I need to buy the tool. Can't seem to find much info on-line about where to buy the Yamaha tool---maybe I have to go to a dealership and pay $$ but might there be a universal tool to do the job?

I'm back on a bike after 25+ years. Love my '07 FZ-6. Last bike: 1971 Honda CB 350. What a difference! Can't wait 'til warmer temps (yeah, even in CA).

 

[Fred]

Motion Pro Tools - SyncPro^™

That should do the job.

 

[Tailgate]

Thanks!

Fred:
Thanks for the info! Checked the site out and ...perfect. I sure like this website; it's invaluable.

 

[ped]

unless the bikes idling rough, they shouldnt need synched. thats what my mechanic told me anyway. i got 20k without them done, everythings fine.

 

[Fred]

It never hurts to synchronize the throttle bodies.

Look at it this way. Your FZ6 is four single cylinder engines, each one is 150cc and has fuel injection and a throttle body. These four engines are connected at the crankshaft.

Synchronizing is a way of making sure that these four engines are working in unison as much as possible. If one throttle body is out of synch, that cylinder will be working a little more or a little less than the others. This isn't bad for anything, but it does make the engine sound less smooth, and will make the engine vibrate more

Synching's main advantage is reduction of vibration and a smoother sounding engine. When I worked as an independent mechanic, I got into the habit of synchronizing every bike I had in my garage. A customer gets his bike back and the annoying vibrations are gone, and all of a sudden you're a miracle worker! :rockon:

I'm rambling. In short, it doesn't hurt anything to check the synchronization on a regular basis.

The one time that you know you have to do this is after a valve adjustment. If you change the valve settings, you can be assured that your throttle bodies are now out of synch.

 

[Nelly]

It never hurts to synchronize the throttle bodies.

Look at it this way. Your FZ6 is four single cylinder engines, each one is 150cc and has fuel injection and a throttle body. These four engines are connected at the crankshaft.

Synchronizing is a way of making sure that these four engines are working in unison as much as possible. If one throttle body is out of synch, that cylinder will be working a little more or a little less than the others. This isn't bad for anything, but it does make the engine sound less smooth, and will make the engine vibrate more

Synching's main advantage is reduction of vibration and a smoother sounding engine. When I worked as an independent mechanic, I got into the habit of synchronizing every bike I had in my garage. A customer gets his bike back and the annoying vibrations are gone, and all of a sudden you're a miracle worker! :rockon:

I'm rambling. In short, it doesn't hurt anything to check the synchronization on a regular basis.

The one time that you know you have to do this is after a valve adjustment. If you change the valve settings, you can be assured that your throttle bodies are now out of synch.

Hi Fred,
Is it standard practice for the workshop to sync the throttles after a valve check? Or is it considered an optional extra?

 

[DefyInertia]

The one time that you know you have to do this is after a valve adjustment. If you change the valve settings, you can be assured that your throttle bodies are now out of synch.

It's the valve check/adjustment that is due at ~26,000 miles, right? TBs are just general maintenance?

I could :rtfm: but it's not handy.
________
HotDiana live

 

[reiobard]

now i have never done this process, how difficult/time consuming is it?

 

[Kakashi]

I'm like you man, back on a bike after 20 yrs. I used to ride an '82 XT500. I find enjoyment out of doing as much of my own work as possible so I purchased an older model Motion Pro mercury carb stick. The only thing I noticed was that it was calibrated in centimeters instead of inches but once I made the calculations (21.9 cm) it was a relatively easy process. I used a volleyball to prop up the tank and a jewelers screwdriver to adjust the airscrews. I bought my '06 FZ in April of '06 and have put almost 18,000 miles on it so far. I started with the standard 4,000 mile service interval and noticed by that time a little roughness of idle and lag in throttle response,so I started syncing the throttle bodies between 3,000 and 3,500 along with an oil change and notice that it keeps the bike running smoother. Invest the money for a service manual, it's great help.

 

[Fred]

Hi Fred,
Is it standard practice for the workshop to sync the throttles after a valve check? Or is it considered an optional extra?

Hard to say.

I was a bit misleading in my post, I think. I'm not a professional mechanic, never been to MMI or any other school, although I do have a certificate in motorcycle repair from the local community college. :thumbup:

I worked in one real shop, which was a Harley dealership. There was no need to synchronize those bikes since they only have one carb.

The multicylinder bikes with multiple carbs/throttle bodies were ones that I worked on out of my garage during a stint as a freelance mechanic.

I don't think that shops normally synchronize after a valve job. You'd have to pay them extra for that service. Mechanics make a flat rate and they're not likely to do work for free.

I was taught to synch the TB's after a valve adjustment because by adjusting the valves, you're altering how each cylinder breathes. Valve clearance has an affect on valve timing, with tighter clearances opening the valve earlier and closing it later. And the valve timing changes the breathing.

Synchs were a lot more critical on boxer engines like BMW airheads and oilheads. On both of those, the throttle bodies are separated from each other and operated by a Y shaped cable. As the cable stretches, the synchronization would go out, so it was a frequent and fairly necessary thing to do. And on those big twin cylinder engines, it had a pretty major effect on the feel of the engine.

And once you get the hang of it, it only takes a few minutes to get the TB's synchronized.

 

[reiobard]

the service manual is in our technical section for download. Don't pay for it.

 

[enjoytheride68]

I use a mercury filled sync tubes. I got my several years ago form JC Whittney. Hope this helps. Justed picked up my new FZ6 yesterday, wife got it for me for my B-Day:]. I am the luckiest man alive. Enjoy the ride, life is too short not to spend it on two wheels, Jim

 

[reiobard]

I use a mercury filled sync tubes. I got my several years ago form JC Whittney. Hope this helps. Justed picked up my new FZ6 yesterday, wife got it for me for my B-Day:]. I am the luckiest man alive. Enjoy the ride, life is too short not to spend it on two wheels, Jim

i should have your wife talk to mine, nice B-day present.

 

[Tailgate]

Hard Copy

On-line manuals are nice and even nicer when offered free. Myself, I'm a hard copy man when it comes to service manuals. It's just not the same, getting oil spots and grease smudges on loose pages printed off the on-line manual.

 

[ender]

This forum is great. Thank you all for taking the time to share your knowledge. ender

 

[stroker]

Check out the Morgan Carbtune. I bought one last year and its the easiest, most accurate sync tool I have used. I can sync my throttlebodys in about 30minutes. :thumbup:

 

[rfkicker2000]

I have a question on syncing myself...sorry post is so long, gotta get the story out.

have an 07 yamaha r6s, bought the morgan carbtune, did the sync, bike vibrated like crazy afterwards. Tried the sync 3 more times, same thing. brought it to the shop, paid $200, bike came back the same and they told me it ran like all other r6's they worked on before. of course, i know different. bike has been silky smooth since i bought it 7k miles ago. tried the sync again, same thing...vibes still there. checked all motor mounts except the rear ones (going to do that this week)...all torqued to spec. idled smoothly at first, now idle is bouncing around alot again. no power or performance problems, just sounds like crap on warm up and vibes like crazy when you rev it up. when riding it, the vibes disappear almost entirely when u pull the clutch in, so i know it is engine-related.

notes: changed oil, oil filter, cleaned air filter, and changed spark plugs...bike ran w/ very minimal vibes (hardly noticeable) until after i messed w/ the sync...then they were very noticeable.

MY QUESTION: shop manual says throttle body 3 should be "Standard" and that 1,2, and 4 should be sync'd to match it. well, i messed w/ tb 3 not thinking it would harm anything. I'm curious if that 3rd tb screw is the culprit. is there any way to set screws to their "Default" position? can you sync by ear? btw, these screws adjust air flow at idle for the throttle bodies.

thanks for any insight you can provide. i don't want to bring it back to the shop seeing as though they soaked me for $200 and didn't help the situation at all.

 

[stevesnj]

YouTube - How to synchronize your throttle bodies.

 

[Fred]

The R6 is a bit different from our Fizzers, despite that fact that everyone here claims that the fz6 "has an R6 motor"

I know the FZ6 more than I know the R6, but hopefully this info will help you out.

If #3 cylinder is the standard, what that means is that this is the cylinder that your MAP (Manifold Atmospheric Pressure) sensor is connected to. On the FZ6, Cylinder 1 has the MAP sensor. This is one of the main inputs for your bike's fuel injection. It should be left alone normally. If you've changed it, you'll need to reset it. For the FZ6, the manual says to hook up a vacuum gauge, and with the engine warmed up and at the correct idle speed, adjust #3 cylinder until it's pulling the right amount of vacuum. For the FZ6, that's 29.0 kPa. The R6 will probably be different, so check your manual. But the general procedure should be the same.

Once you have cylinder 3 back to normal, resynch the other three throttle bodies to match it. Hopefully that will sort things out.

If you still have too much vibration, try synching the throttle bodies with the engine revving (and holding steady) at a higher RPM. I synched mine at about 6000 RPM and it made a huge difference.

Oh yeah, when you're revving the engine with the synch tool connected, don't let the throttle slam shut or the engine will suck up all the fluid in your carb synch tool!

I hope this helps you out.

Fred

 

[TownsendsFJR1300]

Check out the Morgan Carbtune. I bought one last year and its the easiest, most accurate sync tool I have used. I can sync my throttlebodys in about 30minutes. :thumbup:

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I also purchased the Morgan Carbtune. Works really good and there's no mercury/fluid to worry about. I had to buy mine direct from England, maybe $87 total shipped to my door. Do a search for Morgan Carbtune. I've done both my FJR and the FZ6 as well as a customers bike so Its paid for itself already....