[nixRsix]

I'm rebuilding/cleaning my carbs on my 2002 R6 (California bike) and a lot of the parts inside the float bowl are being difficult to clean. I've soaked them overnight in carb cleaner and blew compressed air through. There are still some crud deposits in there I can't get out(in the jets and jet holder). The bike hasn't been ridden in like 4-5 years so I'm thinking about just replacing all the float bowl internals but can't seem to find a good kit. Everything seems like cheap junk and Yamaha factory doesn't make a kit. If I buy the pieces individually from Yamaha, it'll be a small fortune. Are there any kits you folks suggest?

Also, In the early days I had shops work on my bike. I had it jetted back when it was brand new, about 5 years later it was running shitty, and a shop took the jet sizes back down. I'm looking at the jets myself now and they're 138's and 140's, isn't that really small? Smaller than factory? Should I go back to factory size?

tia

 

[gpounce]

My 99 has a Factory Pro jet kit in, and a Hindle pipe. The FP install sheet I got in the pile of docs shows two example setups that say the "unrestricted" 99 uses #152 on 1,4 and #148 on 2,3 and #38 pilots. The "restricted" jets use all #148's and #35 pilots. I'm not entirely sure what the difference is, might be "unrestricted" is an aftermarket free flowing pipe, and "restricted" is OEM.

I have one more somewhat mysterious additional shop receipt suggesting #40 pilots were installed at some point. I had the bike dyno'ed last year, the engine was on the rixh side but fairly consistent, so am suspecting a small AF adjustment to lean it a bit might help.

The FP sheet also suggests 3 .5 mm needle shims and fuel screws 3.5 turns out. Its kind of confusing because rsome ranges of jets are shown in a indiscriminate way.. I suppose back in the day you'd buy a kit then test & tune to find the jets that worked best.

 

[nixRsix]

Thanks for the response! I've got 35 pilots. I wonder why I have such small jets. Maybe I'll put some bigger ones in and see how it runs.

 

[gpounce]

I am guessing #40's on mine given the ambiguous receipt.. but plugs arent fouling and a little bit of enrichener is needed to start cold, so 38 to 40 seems plausible.

When I was tuning on my old Bandit once the jets were close there was significant reaction even to 1/8th turn increments so I expect a lot of possibility for adjustment.

 

[nixRsix]

I bet there is a lot of fine adjustments you can do to these carbs. I just wish it wasn't so annoying to get in there to make adjustments.

 

[gpounce]

from watching youtube it seems to be possible to adjust the AF screws without removing the tank but I'm not sure I believe it

 

[nixRsix]

That sounds like magic!

 

[Smokamoto]

from watching youtube it seems to be possible to adjust the AF screws without removing the tank but I'm not sure I believe it

With the tank off it’s very difficult to do with carbs on & running, air box off...which then things change when the airbox is reinstalled.

 

[nixRsix]

With the tank off it’s very difficult to do with carbs on & running, air box off...which then things change when the airbox is reinstalled.

So keep tank hooked up but out of the way enough to get a screwdriver and synchronizer in there for adjustments?

 

[Smokamoto]

So keep tank hooked up but out of the way enough to get a screwdriver and synchronizer in there for adjustments?

I use a Motion Pro remote fuel bottle hung from the rafters, had it for years. On my ‘02 R6 it’s truly a pain in my hands using a mirror & then a shortened pocket screwdriver to adjust the fuel screws. And a ball-tipped 3mm socket head driver for the screws on the spigot clamps to get the carbs off...what a poor design!

 

[gpounce]

Its been a while since I've had the tank off to inspect whats going on under there so I did that this evening, with a view of looking at the AF screws- looks like <very> difficult access. My bike has a sheet rubber apron down there beneath all the hoses- can't even see up to them from the sides. I have a cheapie extendable snake camera- got a visual on #1 carb AF screw couldn't even get the snake to a place to sight the #2 screw.

On the plus side nothing naughty happening under there so I'll leave well enough alone until I need the carbs off for some reason.