carb cleaning

[andyb]

A good solid wheelie from 3k to 9k, bottle out and let it hit the deck hard, or drive off a curb (speedbumps at speed work in a pinch) will also sort it out.

That can also fix a bike that starts bogging down and running pig rich after a +145mph blast when the slide(s) stick in the raised position.

Don't ask.   

[fjrpierre]

ah hell you were too late with the wheelie advice; i used a long thin piece of hardword and a mallet and tapped each bowl gently as you suggested and voila no more overflow/leak. she's now idling properly and am about to do the sync.

[andyb]

Now you know for the future!!

While you're at it, you obviously have sticky carbs (you poor sod).   It's possible for the slide assembly to stick in an UP position, which causes horrible drivability as the motor goes pig rich and farts and stumbles a lot due to the excess fuel.   This condition is caused by a lack of lubricity between the slide assembly and the carberator body.  The only good way to check for this condition is to put the carbs in an extended session with the needles fully raised and see if they retract correctly.

In summary, take that bitch out and wind it up until you see 155 on the dial.  After you come down to a stop, if it won't idle for crap, you'll need to wheelie it to reset the carbs to a functioning condition.

(maybe once you're home you can put some oil on the slides....)

-andyb

giving unsafe advice since 2005

[fjrpierre]

ok someone walk me through this
bike idles more or less 1k
idle screws 2 1/2 back

homemade syn tool hooked up to 4 ports

at rest the liquid sits nicely at th bottom

on startup

#1 tube is full, the rest empty (so much for my bench sync skills)

by fiddling with the  syn adjust screws i can get the liquid to move to fill #3 or #4 but i cant get liquid in all 4 tubes...

how do i reestablish a baseline at the syn adjust screws so as to get liquid in all 4 tubes while its running , and then   

[fjrpierre]

ok i thought that my homemade sync tool was not holding vacuum properly so i borrowed a morgan carbtune, the queen of the manometers. Hooked it up and presto, strong reading on #1 and nil on rest. played fo several hours with the adjustments and managed to get readings on #1,2 and 3 but nada on #4. Used my last life and called a friend who told me to keep the idle high at all times and keep trying a wide range of adjustments on #4. Finally got a reading on #4 and all the others stabilised suddenly and I was able to sync 1-2 and 3-4 and then the set.

One minute chaos and a weird running bike; the next minute calm and smoothness....



I kept iterating and it eventually sounded so good I buttoned it up, reinstalled everything, got my gear on and went for a ride (after I took the gas tank off one more time to set the fuel petcock correctly so it would actually start with the tank on ). It hasn't run this well in years; no surging, no stumble, even the vibes seem less.

Thanks for all your help guys; I couldn't have done it without you (and especially David's kit and instructions)!

[racerman_27410]

One minute chaos and a weird running bike; the next minute calm and smoothness....

Well done Pierre,

that right there is the look of satisfaction!

it's all not so much a mystery now is it ?

KOokaloo!


Frank

[Arnie]

Pierre,

Now you know how to sync the carbs, you'll find that you do it every time you remove the tank.
Takes only a couple of minutes and makes so much difference.

Congratulations,
Arnie

[mst3kguy]

(sorry, minor thread hijacking in progress)

holy crap, pierre, you've lost a crapload of weight!  you're a lean mean fj machine!

ok i thought that my homemade sync tool was not holding vacuum properly so i borrowed a morgan carbtune, the queen of the manometers. Hooked it up and presto, strong reading on #1 and nil on rest. played fo several hours with the adjustments and managed to get readings on #1,2 and 3 but nada on #4. Used my last life and called a friend who told me to keep the idle high at all times and keep trying a wide range of adjustments on #4. Finally got a reading on #4 and all the others stabilised suddenly and I was able to sync 1-2 and 3-4 and then the set.

One minute chaos and a weird running bike; the next minute calm and smoothness....



I kept iterating and it eventually sounded so good I buttoned it up, reinstalled everything, got my gear on and went for a ride (after I took the gas tank off one more time to set the fuel petcock correctly so it would actually start with the tank on ). It hasn't run this well in years; no surging, no stumble, even the vibes seem less.

Thanks for all your help guys; I couldn't have done it without you (and especially David's kit and instructions)!

[fjrpierre]

actually it's a well known FJ mod; my power to weight ratio went from 1: 7.3 to 1: 6.5 or on increase of roughly 15 HP! So my FJ is running 145HP ! The beauty of this mod is that it carrys over somehow to any bike you ride; my FJR is now running 160HP FJR 

[the fan]

(sorry, minor thread hijacking in progress)

holy crap, pierre, you've lost a crapload of weight!  you're a lean mean fj machine!

I was thinking exactly the same thing, and we only really met once. The heck with the carb tune, whats the secret to the transformation?

[pdxfj]

If you still have the carb tune, sync the throttle bodies on your FJR. 

[fjrpierre]

tomorrow (along with my other sons YZF1000  )