Throttle Body Sync Photos

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broodwich

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Location
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Okay let me just start by saying there is already a great article on how to do the throttle body sync by Warchild on FJRTech.com. Plus you could follow the instructions in the factory service manual. I'm not trying to replace either of those resources here. I just thought it might be helpful to have some more detailed images of the thottle body caps and the throttle body air adjustment screws. Things are packed in pretty tight under the gas tank and it might be tough to identify these items the first time you do this procedure.

These pictures were taken with the gas tank tilted back and held up with some rope tied to the rear luggage rack. Here is a photo of how I hold the tank up.

fjr_tank_lifted.jpg


What you can't see in the photo is I also loop the rope around the metal flange at the top of the tank just to make sure I couldn't nudge the rope loose and drop the tank on my hands or something.

The photos of the caps and air adjustment screws shown below for cylinders 1 and 2 where taken from the left hand side of the bike, the clutch side. The photos for cylinders 3 and 4 were taken from the right hand side of the bike, the throttle side. Also, these photos were taken after I had removed the left and right side rubber covers that sit below the gas tank.

Left Side Photos

Cylinder 1 Air Adjustment Screw

fjr_tb_1_screw.jpg


Cylinder 2 Cap

fjr_tb_2_cap.jpg


I don't know how I missed taking a photo of the cap for cylinder 1 but you can clearly see the cap in the photo below.

Cylinder 2 Air Adjustment Screw

fjr_tb_2_screw.jpg


Right Side Photos

Cylinder 3 Cap

fjr_tb_3_cap.jpg


Cylinder 3 Air Adjustment Screw

fjr_tb_3_screw.jpg


Cylinder 4 Cap

fjr_tb_4_cap.jpg


Cylinder 4 Air Adjustment Screw

fjr_tb_4_screw.jpg


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.

Here is a photo showing my throttle body measurements prior to making any adjustments.

fjr_tb_sync_before.jpg


Before making adjustments there was a 20 mm difference between cylinders 1 and 2, a 15 mm difference between cylinders 2 and 3, and a 5 mm difference between cylinders 3 and 4.

Here is what the Carbtune looked like after I made adjustments.

fjr_tb_sync_after.jpg


The service manual says that difference in vacuum pressure between two throttle bodies should not exceed 10 mm Hg. After making my adjustments cylinders 1, 3 & 4 were all sitting at about 245 mm Hg with cylinder 2 sitting a little bit high at 250 mm Hg. Still within spec at less than 10 mm difference between any two throttle bodies

Edit:

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.





 
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Very nice clear photos, good job. +1 on the Morgan Carbtune II, the best one out there IMO.

Bill

 
Thank you very much for the clear photos, precise locations of screws and caps, and photos of the Carbtune. I've a TBS coming up in a couple thousand miles and I will use your post as a reference.

Dale

 
Thanks guys, I'm glad you find it helpful. Check the bottom of my fist post I just added a link to a video showing the Carbtune.

 
Great write-up and pics. :clapping:

The video was boring but could be spiced up some. How about a scantily-clad umbrella girl pointing to the various rubber caps etc.? :dribble:

No, seriously. It's pretty good stuff. You might want to send the link to morgan AT carbtune DOT com so it can be made available to other

English-speaking FJR1300 owners. The Morgan website has a My Bike section showing how it's done on a number of different bikes.

Stef

 
Great write-up and pics. :clapping: The video was boring but could be spiced up some. How about a scantily-clad umbrella girl pointing to the various rubber caps etc.? :dribble:

No, seriously. It's pretty good stuff. You might want to send the link to morgan AT carbtune DOT com so it can be made available to other

English-speaking FJR1300 owners. The Morgan website has a My Bike section showing how it's done on a number of different bikes.

Stef
Maybe next time I can do some CG to make the bars in the Carbtune bounce up and down as if they were a spectrum analyzer in an EQ and make a music video out of it. :D

Thanks for the suggestion on submitting the info to Morgan. Done.

 
Broodwich - That is awesome, thank you!! :yahoo:

If I may make a suggestion: To improvce this I would have you come down and sync (and film) my throttle bodies and post that. Now that would be great! :lol:

Next Tech day will be up in NoCal!! :dribble:

Thanks again, ride safe. B)

 
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Nice work!! +1 on the Morgan CarbTune. It's what I use. Well worth the money compared to screwing around with mercury and having the potential to make your garge an environmental hazard area!!

 
question, is there one cylinder that is set and then the other are adjusted to it or are all 4 cyliners adjustable?

On my Bandit the number 4 cylinder is set and 1, 2 & 3 are set even with that cylinder's reading.

 
question, is there one cylinder that is set and then the other are adjusted to it or are all 4 cyliners adjustable?
On my Bandit the number 4 cylinder is set and 1, 2 & 3 are set even with that cylinder's reading.
The service manual suggests using cylinder 3 as the baseline but they can all be adjusted. I adjusted them all. The acceptable range is pretty large. The key is to make sure that no two cylinders are have a difference of more than 10 mm Hg. I think you'll be happy and things will be pretty smooth if you can get them all to be pretty close like I did.

Someone with some more technical background may correct me on this one. I don't claim to be an expert here. I just followed directions.

 
+1 on the Morgan carbtune. I bought one a year ago and used it on my first carb sync on the FJR.

 
Thanks! Another thread that cost me more money - I just went to their site and purchased one. Oooooooo this is a dangerous place. :rolleyes:

 
Next time you do a Synch, you might want to check the Carb Tune, and make sure each gauge is the same. I did one on one of my bikes and found the Carb Tune was not showing the same results on the same cylinder. It was off by as much as 20mm on 2 of the ports. The way the unit is calibrated is, he turns it upside down and makes sure each rod hangs at the same distance. This is not very accurate, I used one cylinder and calibrated each rod to the exact same.

Todd

 
Thanks, I just bought a Morgan from one of the forum members and I hope to tackle this real soon.

 
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