Do your valves look like this?
 

Yikes, I was shimming my jet needles today, and I happened to glance down into the intake manifold with a light shined directly into it - this is like the 8th time I've had the carbs half-removed, but just never really looked down there before.

Holy christ, the back-sides of my valves look like crap - all brown-blackish and gunky-crusty. Is this normal? Is it a problem? If so, is there any way to clean them up besides taking the head off and taking them out?

I'd appreciate it if anyone who's had good looks at lots of valves could comment on these pics. Sorry, they're not the best, taken at night.

Attachment 7669 Attachment 7670 Attachment 7671

Use a good quality fuel like Chevron. Also rev the pee pee out of it occasionally. :mrgreen:

Fuel isn't different, the additives that are dumped in the tanks are the only difference.
Your best bet is to run something like Sea Foam every once in a while. Add 4 oz, or a quarter bottle, into the tank at fill-up and drive the piss out of it.

if there is white krusty bubbles on top of the valve you may have a little water mixed with your fuel try some new fuel

That is rather normal but the advice above is good. JIM

Yeah, intake valves usually have some crud on them. You may be able to reduce it but probably not eliminate it. Mine are a little dirty. I don't worry about it.

Yeah, thats what mine looked like when I took them out, but at least the exhaust valves were scorched nice and clean!

Doesn't the ethanol leave more deposits too?

+1, looks like good ole ethanol deposits to me. Some techron will clean that off.

AJ

Yep, mine were bad too...let me know what you find that works?

Is Sta-Bil equivalent to Sea-Foam?

no sta-bil is a fuel stabilizer you put in when you store your bike so the carbs don't get all gunked up. Sea Foam can be purchased at auto zone or other auto store. If I were you, I wouldn't be concerned about those valves.

Mine looked the same way before the top end rebuild (unrelated - bent valves). After that I started to run only quality fuels in the bike, Shell & Chevron, and have noticed that the intake valves are a lot cleaner.

Negative. Like Nath said, Sta-bil is meant to keep fuel from turning bad and gumming shit up.
Sea foam is meant to clean shit out of your engine.

Actually, I was referring to Sta-Bil Ethanol Treatment, not Sta-Bil Engine Stabilizer, sorry. Their ethanol treatment is meant for everyday use and has an engine cleaner in it.