Improvement to Throttle Body Synch

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New member
May 5, 2024
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Waterloo, Ontario, Canada
Spent some time today to improve access when doing throttle body synchronization. My bike is 2007 model.
Here are a few pics to show how.

Need to lift up the tank and support it with a piece of wood, remove the T-Bar and the under tank heat shield.

Pulled all 4 of the old vacuum caps along with retaining ring off of the 4 posts.
#1, 3 and 4 are easier to access, number 2 a bit more difficult due to the large diameter hoses just above the post, shown in pic 6.

Last pic show the Napa part numbers I used, don't know if the US part numbers or elsewhere for that matter, are the same as here in Canada.
The vacuum caps are Napa part number 715-1835, a Dorman product, they came 10 to the box, made of rubber.
You can of course use your old caps, but since my bike is an 07, I preferred new longer rubber caps.
The straight connectors are Napa part number 9862, made by Gates.

Cut the tubing to 4 different lengths, (sorry, didn't measure), so they can be tucked into the sides that will eventually get covered by the heat shield.
Obviously #2 and #3 are longer than #1 and #4.

Added the connector and new cap to one end of each hose. The new vacuum caps are longer than the caps that were removed.
Then insert the open end of each hose onto their respective posts.
They are all a super tight fit, so didn't put the retaining rings back on the new tubing, although could have.

So the next time you go to synch the throttle bodies, the access to hook up the synch tool will be quite easy.
And it will prevent you from dropping your old cap with the retaining ring into the bowels of the engine never to see them again.


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