'01 4k Service - Carb sync'n

[JDinRI]

Hi !
I'm coming up on my 4k Service.
I'm confident that I can do most/all of it myself and I'm looking forward to it - but I've never sync'd carbs. Anyone done this before? Any tips? Where can I get the special tools necessary?

Thanks in advance !
JD

[GoSquidGo]

It's actually very easy, you will need a carb synchronizer (I use mercury carb stix that I bought over 10 years ago, were like 30 bucks then) and probably a long flex handled screwdriver would make it very easy. You will need to take the airbox off to get to the screws that are found in between the carbs. All you do is get the bike up to operating temperature, and synch 3 of the carbs up to the one that is running directly off of the throttle cable. You can blip the throttle slightly to check the adjustments, but to not rev it up and close the throttle quickly, as you may suck mercury into the intake ports at high vacuum. Make sure you recheck your settings after you tighten down the locknuts on the adjusters.


Good luck!!

[winders]

GoSquidGo,

That's not how it works.

Yes, you want to warm the engine first but you want to make sure the idle speed is set to 1050 RPM to 1150 RPM.

Then, you adjust the balance screw between the #1 and #2 carb to balance them. Then you adjust the balance screw between carbs #3 and #4 to balance them. Finally, you balance carbs #1 and #2 to carbs #3 and #4 by adjusting the balance screw between carb #2 and carb #3.

The balance screws don't have any locknuts to tighten down.

Scott

[GoSquidGo]

Sorry 'bout the locknuts, haven't done my R1 yet (it wasn't out of sync)

Also I wasn't aware that the order effected the outcome as long as when you got done, the carbs were all pulling the same vacuum. Thanks for the detail.

[winders]

Well, you could balance carbs #3 and #4 first. Then balance carbs #1 and #2. The key is that the adjuster between the #2 and #3 carbs balances the right and left carb pairs.

Balancing the '02 R1 throttle bodies is really weird.....

Scott