So, after the maiden ride on the new suspension, I pulled the carb on ye ol’ WR426 again. It had been running pretty well (other than lack of idle) when I blew the fork seals, so I wondered what was up. Well, after dropping the bowl, I discovered a ton more green crap in the bowl. Yup, time for another clean out. When I picked it up from Santa Cruz Suspension, Rich did point out the all of the rubber venting in the gas cap had decomposed and landed in the tank. That was a new development, that I should have investigated further, but I was in a hurry to ride! Anyway, Rich was kind enough to drain and rinse out the tank, even giving me all the rubber back (in a plastic baggy).
Well, at this point I’m done screwing around. I’ve ordered a new gas cap, all new fuel line, and a petcock rebuild kit. Meanwhile, the carb is in the mail to Zip-Ty Racing. They’ve developed a carb mod to cure the back firing problem and provide crisper throttle response. As an added benefit, before they get started they drop the carb in their Ultra Sonic Tank for a good thorough cleaning.
The carburetor rebuild will probably give you the most bang for the buck. At least I hope so.