idle screw and balancing

[b4cruz]

What is the proper way to adjust the idle speed screw?
I have it turned to the lowest opening: just before the screw pops out.
When I adjust it to open more the idle jumps to really high RPMs.
I make 1-full-circle-turn-adjustments when the engine is off.

I can't balance my carbs until i can get the idle to stay put.
The carbs are clean and perfect now all passages are clean
and the needles move properly; seated at the stock position.

I have really healthy spark and a fresh new battery.  The throttle
cable is properly adjusted and neither it nor the choke cable
are getting tugged or locked up.  Fuel and vacuum lines are good too.

[b4cruz]

ok after lots of fiddling I have a good idle

it will rev up once but then it won't anymore.  
it will only rev to 5000rpm then only 3000rpm and sounds awful.  
I have the airbox off so i can look at the needles.  
On the first clean rev everything moves properly and evenly.  
When the revs go bad the engine sounds horrible
and the needles start moving differently and gas starts spitting up.

this is definitely a carb balancing problem right?
the balancing tools are expensive $50-100; and they run on mercury?
Should I just buy new carbs or will they need to be balanced too?

is there anything else that could cause the bike needles to act strange
after they get revved up to higher RPMs?
could it still be the o-rings or the jets?

does everyone hate my scatter-brained posts already?

[Zhi]

How was the bike running before you started working on it?
Have you given the carbs a good look over and cleaning? Clogged idle mixture passages can cause rough idle.

[b4cruz]

Before all this mess the bike ran good; let it sit a month
and it started having the start & idle problems

yes carbs have been cleaned twice now
everything moves and slides perfectly
The needles sit right where they should on the stock clip

Its just when you give it a good rev over 10000rpm
after that it won't rev up past 3000-5000 RPM
no more idle and start issues
its all in the high RPM now

[PitterB4]

After all that messin' around with the carbs, they certainly need to be balanced.  New ones likely would need syched, too.  The Motion Pro Economy carb tool can be had for <$50 and works great.  You'll also need a way to feed fuel.  I just bought a long tube and use my tank (on a high shelf) set on prime.  (The Motion Pro aux tank is about another $50.)  You also need to make sure you block the vac tube.  For that I fold it over and use a small vice-grip.  

It does still sound like you have some weird carburation problem, though.  Do all 4 header pipes get and stay hot?

[b4cruz]

yes all four pipes start hot and stay hot
evenly and they cool down evenly too
all 4 are firing

i also learned if i roll easy on the throttle it stays alive better
all that blipping gave me a BIG backfire so I stopped that
i'll try to ride it around tonight and see if rolling will
get the engine back to a respectable state

i think i'll just pay someone to balance the carbs
it costs like $50 for the tool and then
you have to buy mercury for it
the shop won't charge much more
and they can check if there is
something else wrong
the local shops down here are just
so damn slow
so many bikes in line before me
usually takes at least a week to get anything done

[PitterB4]

FWIW - the $50 includes the mercury.

[b4cruz]

I just got back from riding the b4 its got a bad dead spot @ 5000rpm.
its so random. it sounds like a dying gargoyle when it gets stuck there.
I have to drop to another gear and rev up slowly and hope it passes.
outside of that the bike runs fine; well, i do have to straighten the rear
wheel its kinda pushing me sideways

There is no space at any of the shops. Nobody wants my bike right now
& it'd take over a week before they'd even look at it!

So I'm gonna buy the Econo-Carb tool and see what i can do.
I think I can jimmy something for the tank line.
This way I can set the carbs myself everytime:
after valve jobs, new carbs ect. ect.
Looks like mercury refills aren't very expensive anyway.

its so sad - for me and my last minute to go attitude
good bike shops are never not busy
they are all totally booked
especially the honest ones!

[stormi]

"I have the airbox off so i can look at the needles. "

I was once told by a "bike guy" that came to see my Dita, that she wouldn't run properly without the airbox on.  That she depended on some sort of vaccuum that would be generated with that in place.  He made a special point of telling me that, so that I wouldn't panic if (when) I ever tried it. :)

of course, he's used to CBR 600 and 900s,.. but he's fixed a lot of bikes,..

YMMV :)

HTH
stormi

[echomadman]

http://www.powerchutes.com/manometer.asp

cheap home made carb balancer.
I have a 4-way Carbtune2 balancer and its really handy, but for a quick on the spot fix, that one there should let you get your carbs in synch.

put the airbox back on when you're setting the idle and balancing the carbs, it makes a big difference.

[b4cruz]

It cost like $3 at home depot to build the carb tool. I used shorter free paint stirring sticks for easier use If your carbs are really out of whack then a yard stick is probably better because my shorter version sucked the oil up really quick.  Once I got close though it was perfect!

THANKS echomadman

I also rebuilt a loose connector on my headlamp; it was cooking the wire.
Don't know if its the iridium plugs or the stock needle setup but it seems like I'm getting over 55mpg!
Using Kawi chain foam; I think I like it so far (cheap too).
Also using diesel syn oil and it hasn't burnt up.
It took a whole season, but I can't believe i actually learned how to do all this crap!  I mean if you saw my garage and methods and my depressed defeated complaining state you'd think I was crazy.  I still can't believe it runs as good as does right now.

thanks to everyone
for putting up with my "turbo typing" and all my blunders in the garage

As far as the idle problem I also learned that the tank can really tug and snag the throttle cable when its not positioned in the proper place.  I route it under the air outlet hose and now it works perfect.

side tank repair setup & repaired connector
http://flypicture.com/p.cfm?id=55228

the carb balancing tool
http://flypicture.com/p.cfm?id=55229

finished product
http://flypicture.com/p.cfm?id=55227

tool kit under the seat
http://flypicture.com/p.cfm?id=55226

[PitterB4]

Dude - I'm glad you finally got her running!