Carbs carbs carbs (Buddha!)

[The Buddha]

You boiled the carbs ? Whose idea was that ?

The O rings could be eaten, those guys actually react the worst to bleach. They can stand up to almost anything except bleach.

4 turns out - well try 1/2 or 1 more. If the O rings are not dead.
Cool.
Buddha.

[romulux]

Not bleach, a little lemon juice.  And no orings were boiled.  They were disassembled first and only the metal parts went in.

It's just something I read somewhere.
http://www.google.com/search?aq=f&sourceid=chrome&ie=UTF-8&q=boil+carbs


joshr08, I'll clean the carbs again if it comes to that, but it's a multi-hour job and I'm lazy as hell.  If I'm going to take them apart, I'm going to do it right and completely disassemble them.  I would like to avoid that if I can.


Here's what I'll do: I'm going to adjust the float level so it's level with the edge of the bowl or so.  That will test what joshr08 said about the floats being high enough to supply fuel even though jets are obstructed.  It should run worse if I do this.


Thanks for all the suggestions.  Buddha, I'll reset the mixture screws out to 5 turns while I'm at it.

[acid]

Forgot to mention this is 4 to 5 turns out with the mixture screw.  I don't want to screw them out much further.

That's far too much. Standard is around 2 turns o_O

[romulux]

I spent a few hours today to do the following

- set floats right where they should be (top of float 14mm above edge of carb rim when inverted)
- added 2 washers to each needle from the jet kit from Buddha, since I hadn't done that
- pulled the brass jets to look at them -- they all look clean and let light through where they should.
- bowls are clean, no varnish or gas crud

I have not had a chance to see how it runs other than to let it warm up a little bit before it began to rain.

[romulux]

Rode around a bit today.

No change in behavior - a little choppy when starting from a stop.  The plugs are dark when warming up with the choke on like you'd expect them to be.

Turn choke off and ride around, and they become very white.

So then I waited for it to cool down and I removed the air screws from the carbs.

The air screws' springs had white residue or corrosion on them and the washers were rusty.  And I lost one of the o-rings getting them out, so now I have to order stuff anyway.  I will get a cheapo air compressor with a blow gun so I can blow air through the passages, too.

In conclusion, I'm an idiot.  I didn't want to believe the carbs were dirty because I didn't want to clean them.

I will
- order the parts I need
- clean the carbs + spray out with compressed air

[joshr08]

thank you for taking them down again.

[romulux]

Ok, so I cleaned them again and replaced the corroded pieces of the pilot screw & oring.

Really, no change in terms of leanness.  Pilots are ~4 turns out.  I let it idle for a while after riding around and checked the plugs.  They're as white as can be.

If I screw the pilots in, the closer to in all the way, the worse it runs.  RPMs lower and it sounds rough and will eventually stall if I turn them in far enough.

Turn them out, and it seems to run much more smoothly except for some misfiring at 2000rpm (usually for a minute or two after starting the bike, even when hot).  It seems the further out the pilots, the less misfiring, but it isn't eliminated completely.

There is still hesitation from when first rolling on the throttle from a stop.

Even though I like to do all my work myself, I would almost take it to the shop at this point just to see if they can diagnose it, but cash is very tight and they're $85/hour.

[romulux]

The only other clue is that when I first start the bike with full choke, if I try to use the throttle at all, it wants to die and stays around 1500 rpm.

Then if you wait 10 or 20 seconds, you're able to use the throttle without it dying.

No more ideas from anyone?

[OilSooner]

clean your petcock.  esp the gasket on the inside of the diagphram.  Takes 15 mins.

make sure all the fuel hoses are routed down hill, consistent with being gravity fed. (also, not crimped anywhere, including breather hose)

make sure the vaccuum hoses are ran correctly.

Pull your dipstick to ensure the crank case doesnt have gas in it.

check the positioning on the choke and throttle cables as they are connected to the carb.

You can do all of this in about 30 mins, and it will rule a lot of stuff out, or point you in a more useful direction.

Also, open your gas tank at start up and see if that helps.  Leave the lid open when you start it.


what the charge level on your battery?
good luck.

[romulux]

clean your petcock.  esp the gasket on the inside of the diagphram.  Takes 15 mins.

make sure all the fuel hoses are routed down hill, consistent with being gravity fed. (also, not crimped anywhere, including breather hose)

make sure the vaccuum hoses are ran correctly.

Pull your dipstick to ensure the crank case doesnt have gas in it.

check the positioning on the choke and throttle cables as they are connected to the carb.

You can do all of this in about 30 mins, and it will rule a lot of stuff out, or point you in a more useful direction.

Also, open your gas tank at start up and see if that helps.  Leave the lid open when you start it.


what the charge level on your battery?
good luck.

Thanks for the ideas.

The petcock is from an '04 that I've ground the tab off of to use gravity feed to bypass the diaphragm and it's clean.

Vacuum hoses should be correct and given that the symptoms have not changed over several disassembly and reassembly, I have to assume they're where they should be.  The other options is that I could be reassembling it consistently wrong.

I check oil frequently.  It's at the full mark and doesn't smell of gas.  I'm curious why you suggested this -- how could gas get in the crankcase aside from past the piston rings?

Choke and throttle cable action is smooth.  I just assembled it on the weekend, so I know they're tight and OK.

Next time it's cold, I will try with the gas tank open -- that's one I haven't tried.

I use a battery tender, so the battery should be good.  I've never had trouble with it, but I haven't really done any diagnostics on it (due to lack of problems with it).  It's the one that was on the bike when I bought it, so I don't know its history.  Fluid levels are good on it.