idle surge (bad throttle cable?) and stator cover gasket
 

hi all, just got my bike back from a local mechanic, who (hopefully) fixed on my leaking petcock and carb problems. been about two months since i had the bike out. $150 to replace the petcock (my part), replace the seal between the two halves of the carb, change the oil and filter (my parts), replace my horn switch (my part), and check the rear tire and suspension (it feels a little uneasy to me in turns, sometimes; the tires are 6 years old, but the mechanic said they seem soft enough, and he rode it a bit and said it felt fine).

when i picked the bike up, i noticed a little oil dripping; after removing the sprocket cover, the mechanic said it was the stator cover gasket. i get the bike home (had AAA tow it for free) and then notice that the oil is overfilled, probably by about 0.2 quarts. a 16-or-so year old who works for the mechanic had changed the oil and oil filter, and gave it about 1.5 quarts, judging by how much was left in my second bottle; i found out the kid didn't know there's a window that you're supposed to use to judge the oil level.

could overfilling have caused the leak, or a gasket failure? i painstakingly got some oil out (it might still be slightly overfilled, but it's not by much) and rode it around a bit, but it still seems to be dripping oil very slowly.

another problem i just discovered is that the engine revs wildly when i turn the front wheel to the right; i assume it's a problem with the tightness of my throttle cable, or the cable itself. is adjusting it easy? i'm worried it might be more than just the tightness of the cable: yesterday after riding, the idle, though it was good when i started my ride, was way too high when i parked the bike (with the wheel pointed straight forward) - though today after a ride of similar time and length the idle was fine afterwards.

as always, thoughts much appreciated.

The wild throttle could be the cables are getting hung up on something. If the tank was removed during repairs a cable could get snagged between the frame and tank. I would look there 1st before doing a cable adjustment that make not be needed.



Oh, and I would also check the cable attaching mechanism to the carb itself. They worked on the fuel system so there might be a SNAFU in the mix.

Yes, an overfilled engine can cause gasket blowouts. The excess pressure is looking for ways to escape to relieve itself, and if it doesn't happen quickly enough, then any weak link in an aging gasket will get exposed.

You might be able to snug up your bolts and see if that stops the leak. Is it a dribble or a gusher?

The engine rev is undoubtedly a kinked throttle cable. As WW suggested, check the route to ensure it's not bound up in a little crevice somewhere and go ahead and lube it up to help ease binding in the future.

Kid: Make sure to let the kid know after you figure it out, he still has to learn.
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Idle: I wouldn't worry about that, mine does that too, when hot, it idles much higher.

And re: the throttle cables, check their route asap for them being stuck somewhere.

That's why you should always set the idle speed (with the big white knob under the carb) when the engine is HOT. (Suzuki recommend 1200 to 1400 RPM) :tup:

thanks again, all!

turns out it was the clutch cable getting caught...woops. mechanic zip-tied it and a few others, and the idle surging problem went away.

oil and gas seem not to be leaking now, though i'll still have the stator gasket replaced, since it seemed to be leaking slightly before.

a new symptom today: right as i was finishing a ride back from the store, i heard this strange metal-y sound - like a light rubbing sound with this sort of faint metal squeal to it. i couldn't tell if it was coming from the engine/clutch/etc. area, or if it was occurring while i was turning my front wheel. it happened for a block or two, then i couldn't get it to happen again while idling the bike and giving it gas, nor when i went for a short ride later. if it matters at all, it was very hot today - close to 100, and humid - and the ride i had just finished when i heard the sound was only a few miles. oil level looks to be where it should.

as an aside, if suzuki had ABS on the gw250, i'd buy one tomorrow! cheapest new non-sportbike with ABS looks to be honda's CB500F at about $6,000, which is above my budget. hope more small bikes see ABS soon.

Have you checked the brake pads for wear? Seems to sound (from your description) that the pads have worn away, and are rubbing on the caliper.