Will start and idle beautifully, but makes no power and will die when taking off

[The Buddha]

OK issue fixed (I hope)

I set floats rather low (leaving too little fuel in the bowl) - Issue persisted.

Then I took off the floats and dropped em in gas - no sinky. All floaty. Grrrr

That last time when I pulled the carbs I tipped em over into the gas can (to empty the bowls - yea they say never to do that, but I have cleaned the carbs 300 times and opened it up 350 times the last 4 days, so I knew it was not going to get any more junk into the jets). And I blow tested it. It blowed through fine, and it nicely sealed up too.
Then I put it back on and tried it ... and vroom vroom.

Ergo - I either had a blocked vent to air from the carbs, or had a fuel line block ... or a gremlin climbed in and ruined it, and it ran away and its fine. If it ever comes back, I'll be in trouble.

Cool.
Buddha.

[Big Rich]

You need a gremlin bell. Ha.

Well, it's good the bike is up and running again!

[The Buddha]

It was bad for over a year, and it got suddenly unuseable. It would still idle perfectly.
I am leaning toward that top vent, cos a blocked fuel line wont flow better when the fuel useage is a tiny fraction of the max @ speed.
Cool.
Buddha.

[The Buddha]

And its gone back to the way it was before it completely went kaput.
I suspect something is clogging up the fuel passages.
Cos the last few times I pulled it apart, I got something in the fuel line that looked grey sediment like.
And not coincidentally, the tank is coated with POR15.

I suspect its coming loose.
I may re run it with that black tank I ran it a few yrs and try checking this one.

Cool.
Buddha.

[The Buddha]

Tank is clean. POR15 isn't coming off and gumming up
OK ... this is a first (for me) but someone has sent me a carb rack they said had a leak @ the butterflies. I used it for parts and tossed the carcass a few yrs ago. There was a leak in that @ the pivot.

Also how can that affect both carbs. I suspect whatever it is, is pertaining to both carbs. I'll trouble shoot more and post back.

Cool.
Buddha.

[The Buddha]

It also sounds/feels like the slides are coming up too fast.
Except, they have been @ this setup for 3k miles, and it was always acting up when cold, but 30 sec after trying to take off, it would get normal and stay fine till the next cold start.
Cool.
Buddha.

[rg500gamma]

Buddha  ,  will bike go up a  steep hill (  i.e. Colima road by me in whittier ca.)  at  60 m.p.h.  ? 

[The Buddha]

Buddha  ,  will bike go up a  steep hill (  i.e. Colima road by me in whittier ca.)  at  60 m.p.h.  ?

No It wont even go up a not too steep hill. It barely goes up my driveway.
Cool.
Buddha.

[vipster76]

do you have another set of carbs to try?

[rg500gamma]

do you have another set of carbs to try?

+1  really need to try a second set of carbs. if bike cannot go up a hill at 60 m.p.h.

[The Buddha]

I know its the carbs. The thing is, the cable has been modded for an 01-02 carb set. So I'll need a 01 or later, but I am pretty good @ doing repairs 1 at a time and testing it out. How else do I learn
Anyway - My next stop is to slow down the slide's lift rate.
Cool.
Buddha.

[lucas]

Buddha, have you verified that you are getting spark to both cylinders?

Also if you check the temps of the exhaust tubes you might  narrow your search down to one side of the engine.  If you have a meat thermometer, kitchen thermometer, or even touching the exhaust tubes with an oven mitt and comparing the heat transferred by each.

[The Buddha]

OK now that the weather is warmer (I guess) it seems to take for ever to warm up, and as it does it will start accepting throttle, it will rev to 3k before choking or gasping, a few mins later it will rev to 4k, few mins later 5k, few mins later 6k and 7 and so on.
I have not tried to ride it. It may still not make power. Revving is different form making power.
Cool.
Buddha.

[lucas]

You could try pulling the spark plug wires while it is idling to see if the rpms change.  While you're doing this you can visually verify that you are getting sparks by holding the open end of the wire close to the end of the spark plug and watching for arcs to jump out of the open plug wire.

[The Buddha]

And this morning it didn't even seem to act up at all. I dunno what I even did to fix this, if I even fixed it.
Its got both cyls running, it falls on its face when you rev it but not lose a cyl, the thing just feels like its getting too much air, that was when it was acting up.
Its rather similar to the symptom when your slide rises too fast. But that usually happens 1/4 throttle and up, and you can get it to work right with slower opening of the throttle.

Cool.
Buddha.

[The Buddha]

It acted up a wee bit today. But 2 mins of idling after 1 min of choke - and it was running like a champ.
I am still a shade lean @ 1/2 throttle, cos I got rid of 1 washer from the needle. Gotta get back to the thing and put it back in.
Cool.
Buddha.

[The Buddha]

And on my way back from work today it acted up for a good 3-4 mins. But about 1/8th mile and 2 lights of screaming on choke later, it caught its breath and ran like the proverbial scalded bat out of hell - for a GS that is.

Is it possible the slide is lifting just a shade too fast when cold, but the bike is able to process the extra air and fuel when hot ?
I'll slow the slide down and try next.

Oh yea, float level is low too. Gotta fix it next try I'm in there.

Yea the valves are wee bit loose. But just a little racket, that's all. Compared to the Yoshi Tri oval howling away, its just a little music.

Cool.
Buddha.