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View Full Version : Cleaning up the fuel system in my '96 CBR 600 F3



rifleshooter
Sat Dec 21st, 2013, 07:08 PM
With classes out yesterday (I'm a teach) I've decided to get to the root of my full-throttle problem. Symptoms? Running lean in hot weather in top gear between 5-6k.


Bike is 18 years old, so I figure it needs a little help. I looked into the tank and saw what I thought was a bit of the old red stuff. A further look into the tank reveals that it's pretty clean, with perhaps a tot of rust near the seams (where they always rust.


I spent the last 4 hours removing plastics, taking the tank off (I've never done this on a bike, and it was not all that fun), and taking off the very complicated intake system. I am now down to loosening the screws on the carb boots (the manual refers to them as the "insulators") and cannot see any but the left-most screw. I see #2's if I really get the flashlight in there but see no way to access it. Any tips or hints as to how I can find these bad boys?


I pulled off the fuel filter and emptied it into a gas can. I wanted to tap it on the table-top to see if any debris would come out, and was surprised to see it producing rust...


Wads of rust. More, and more, and MORE - it was like that weird hard zit you get that you just touch and it shoots pus, then 10x as much crap comes flying out of it than you ever imagined could fit in there.


The pile of rusty dirt was close to a tablespoon! No wonder why I was running lean!

rybo
Sat Dec 21st, 2013, 08:53 PM
A lot of times the screws on the carb boots are linked together so turning to outside one loosens two at the same time. If that isn't the case I've had good luck loosening the outside two an wiggling the rack of carbs loose. Once the carbs are out of the way you can loosen to boots and position them for easier access in the future.

Certainly rust and bad gas can be a big part of your problem. We chased it for almost a whole season on Sarah's CB1 (1989). It ended up being the tank, so we ended up cleaning and coating the inside.

rifleshooter
Sun Dec 22nd, 2013, 12:25 AM
I am hoping that with daylight I can see a way to make the inner screws. I'm just not getting it in the dark. A lot of stuff is in my way, stuff I can't just take off - so I'm at a loss for what to do at this point.

Perhaps I'll see the answer tomorrow morning.

rifleshooter
Tue Dec 24th, 2013, 02:06 AM
Well, I found out what I was going on about - I was trying to unscrew the carb-side of the boots, instead of the head-side. The carb-sides are all up high, the head sides are deliberately kept/trapped against mini-rubber stanchions on the boots themselves so they can't twist when loosened or tightened; this keeps them oriented correctly for access from either side.

I got the bands loose (but not loose enough, then I did something stupid (that, after the cursing and the kicking of the trash can) that I discovered wasn't too bad and could be fixed for about $25. I've taken down carb #1, cleaning all the jets (just not the pilot yet, I'll get to it tomorrow when I figure out the crazy D-shaped mixture screw tool (or cut a slot with a dremel for access with a flathead). Carbs were not lacquered too badly, much less than some pics I've seen on the net.

Everything's soaking in kerosene right now. I figure this is the best way to prevent harshness of something like a ChemTool from messing up rubber if I have missed stripping something from the carb.

Does anyone here have a temporary gas tank and a carb synchronizer I can borrow?