Throttle Body Sync Photos

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That's some excellent photography and a really good writeup. You need to get a commission from Morgan as you just sold another Carbtune. :)

 
I didn't know you needed a pencil for a TB sync? What does poking everything with a pencil do? :rolleyes: :p
Using a pencil is just cheaper than using a tube of powdered graphite lubricant.

Wait, no, graphite is conductive. He's using the pencil to ground himself to bike to prevent a static discharge.

It's dual purpose!

Sometimes you have to explain the simplest things to some people...

 
Hello All.

I do have a M-Carbtune and did use it successfully on my 07.

As it's almost time to sync them again, a question.

Is there a special tool that is used to remove (without loosing) the wire retainer around the rubber caps?

I modified a stiff wire to hook onto them, but there must be a better way?

Thanks.

Kirk

 
Good stuff. Very clear pictures and video.

However, in my mind, synchronizing the throttle bodies at idle via the air screws is only part of the job. It will primarily effect the smoothness of the engine at idle, since as the throttles are opened the air screw's contribution becomes less and less significant.

The second part of synchronizing the throttles is making sure that as the throttles open they do it in unison. This is somewhat controversial as messing with the mechanical linkage can get things completely out of whack. However, this really isn't rocket science, just basic physics, so we should be able to figure out how to do it without messing things up to badly.

Here's a link to an old discussion about throttle body syncing and there is a link in the first post on that page to a Word document that I find to be very helpful.

 
Yes, when I did the TB sync on my 06 AE. Things didn't change too much. I noticed that the air screws are very loose, and probably would change over time with engine vibration. Also, I feel that you must put the engine undar a load to get a proper sync. So next time I will do that and find a way to make the air screws not so easy to turn. Any ideas would be helpful.

 
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Thanks Broodwich,used your pics as a map to do my first time throttle body syc. The way things are covered up in there, I could have spend more time searching than working.

 
Yes, when I did the TB sync on my 06 AE. Things didn't change too much. I noticed that the air screws are very loose, and probably would change over time with engine vibration. Also, I feel that you must put the engine undar a load to get a proper sync. So next time I will do that and find a way to make the air screws not so easy to turn. Any ideas would be helpful.
They make some wicking loctite (220) that is a penetrating type for small preassembled fastners that may work.

Clicky

Wrench

 
Is there a special tool that is used to remove (without loosing) the wire retainer around the rubber caps?I modified a stiff wire to hook onto them, but there must be a better way?
I used needle nose pliers to remove the wire retainers, but your way is probably safer. I saw no need to replace the retainers after the job, however, so it got easier after the first time.

dbx

 
Yup, I would agree that a stiff piece of wire is the way to go. I just did a TBS this last weekend as well, and I used apiece of wire that was left over from when we ran some electric fencing. I would be very concerned about trying to get the clips off with a pair of needle nose. Especially that damn #2 position, what a ***** that one is.

That being said, I have been very surprised each time (4total now) I have done a TBS at how little adjustment they need.

 
For the initial 600 mile TBS, I used one of the hooks from a hook and pick kit (found in any automotive tool section) to remove the wire retainers. These tools are much easier to hook onto small wire retainers in cramped areas and prevent the retainer from being dropped into the engine space while pulling it off the rubber vacuum cap.

Additionally, I also replace the factory rubber vacuum caps with longer caps that can usually be found at any automotive supply store for a couple of bucks for a set of 5. These replacement caps are easier to grasp and remove by hand. As noted earlier in this discussion, I also do not use the wire retainers once initially removed.

 
I just uploaded my first YouTube Video ever. I have titled it, the "Worlds Most Boring FJR Video" ever. I filmed the whole 12 minute process of syncing my throttle bodies. Don't worry I edited the video down to just over 2 minutes. So if you ever wanted to see what the Carbtune looks like in action, and I use the word "action" quite loosely here, check out the video I uploaded.




Quicky question....

Looks like #2 was a ******! It read "high" from the get-go. Were you never able to get it "exactly" the same as 1, 3 & 4?

And how many "turns" out from seated, especially compared to the other 3 air screws?

Oh, BTW...your Feej sounds smoooooooooth. Good job!

 
I just ordered a Morgan sync tool from the UK... At the current exchange rate, I got it for $88.00 :yahoo:

If anyone is thinking about ordering one, now is the time to get it.

 
Just used this thread, Warchild's, and my new Carbtune, to dial my bike in before heading up to Denver next week. Thanks for taking the time! :clapping:

 
I use the Morgan Carbtune II calibrate the throttle bodies. The service manual calls for the vacuum pressure to be between 220 and 280 mm Hg, the middle of that range would be 250 mm Hg. The solid lines on the manometer are spaced at 20 mm apart. Each of the dashed marks in between a solid line are 5 mm apart.
Great info; thanks. I have not done this yet on mine, but need to learn how to; this makes it very understandable.

I have a Q tho; you mention above the 220 to 280 range; is there any advantage of going to one end of the range? Towards 220 or 280 vs in the middle?

I have an issue with mine that it stalls sometimes when I come off the throttle usually to come to a stop/slow turn, something like that. The bike idles OK when you're just sitting there albeit a little rough IMO. I would really like to correct the stalling and I do not know that this adjustment has anything to do with it, but I'm curious about the Hg readings regardless.

 
Do not worry what the absolute vacuum is. Just balance the 4 cylinders to each other (actually balance all the other cylinders to #3) with the idle speed at 1100 rpm. The vacuum in that condition will be what it will be, and what it actually is matters not at all.

For the stalling issue, set your warm idle to 1100 rpm. Not any lower.

 
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Do not worry what the absolute vacuum is. Just balance the 4 cylinders to each other (actually balance all the other cylinders to #3) with the idle speed at 1100 rpm. The vacuum in that condition will be what it will be, and what it actually is matters not at all.
For the stalling issue, set your warm idle to 1100 rpm. Not any lower.
Thanks

 
Good stuff. Very clear pictures and video.
However, in my mind, synchronizing the throttle bodies at idle via the air screws is only part of the job. It will primarily effect the smoothness of the engine at idle, since as the throttles are opened the air screw's contribution becomes less and less significant.

The second part of synchronizing the throttles is making sure that as the throttles open they do it in unison. This is somewhat controversial as messing with the mechanical linkage can get things completely out of whack. However, this really isn't rocket science, just basic physics, so we should be able to figure out how to do it without messing things up to badly.

Here's a link to an old discussion about throttle body syncing and there is a link in the first post on that page to a Word document that I find to be very helpful.
This is exactly correct and there should be a way to correct the linking at part throttle also. more important than idle to me.

 
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