Hi - couple of weeks ago took carb apart & replaced white spacer with one 2/3 as thick. @ same time took out 2 little washers (not on diagram & seem to me superfluous) between the clip on the needle & the washer above the spring.

bike would only run on full choke & then very poorly - any opening of gas would kill it.

so, put it all back as it was. & it seemed to be back to normal - odd pop when snapping shut throttle but that was about it.

lately has been more temperamental to start in mornings (when I leave for work it is in the upper 30s) - needing choke then running down road only on choke (or dies) popping & banging. after longish ride stops banging & can put choke in.

today was worse - would start but any gas would kill bike - went down road but hads to come back for car.

tried later today when warmer - still a pig & would only run poorly on choke. have a 150 main (put in by mechanic before I got up the courage to rip into carb), pilot left standard according to him @ 52.5. air/fuel screw is about 2 & 3/4 turns out. like I said standard white spacer.

bear in mind am in desert @ 4,500 feet so usual sea level jetting doesn't apply.

I have a slip on K & N filter & a slash cut hard chrome muffler.

so - any assistance out there would be gratefully received.

thanks in advance for help.

Sounds like it is broke to me.

I read your post but my brain is too  tired to think right now ... I tried to go through it but I am forgetting a line as soon as I read it.
I will come back in the morning when I can think normally.
Sorry for the delay.

Was the slide very clean - no oily finger prints no anything ?

thanks for help everyone.

will try screw further out, mick.

no, know I put slide spring in as almost didn't & noticed @ last minute!

maybe need to clean slide, reelthing & steve530 - was not overly careful to not get fingerprints on it. thanks.

steve530 - know got diaphragm lined up OK as friend & fellow countryman mickthelimey advised on need to do so in e-mail, pre my stripping carb.

lancer - would appreciate your revisit to this & any input you can give. thanks.

forgot to say last time I use iridium plug if that is any consequencies & last time I looked it might be a little sooty.

please note - took apart carb, had immediate trouble & put all back as was. 2 weeks later then started to get more difficult to start, accumulating in yesterday's real issue.

Only running on choke, then dies or run/choke and then runs but poorly........

Pilot circuit clogged up somewhere,  check all passages and pilot jet itself.   If you have not done so already, you need to get lots of carb cleaner and compressed air to blow out the lines.  Be very careful about pushing wire into the passages to clean them out, it can damage the passages and block them with metal from the walls.
Also check pilot air adjusting screw and it's seat for dirt and damage.

As already mentioned, it sounds like the slide is not operating properly.  You said you installed it correctly so the rubber diaphram is seated properly, but did you do a REALLY GOOD CLOSE UP INSPECTION of it to see if there are any tiny holes that would affect the vacuum operation?    Hold it up to a light buld and scan for little holes.  The overly rich running condition makes this a possibility, not allowing enough air to pass through for the amount of fuel & creating an overly rich mix.

Actually, since you will have the carb off the engine again you should take the carb down to its' naked nothingness.  Every tiny piece. ... clean and blow out every orafice from from every angle 10 times, to insure all passage lines are as clean as new.  Spend a good 30 minutes on this alone.
This should be the FIRST STEP for anyone who is trying to fix a carb problem.

are you getting gas in the petc0ck vac line?

no offense but did you suck on it?

I think lancer has a clue, with no vacuum hooked up, it's running... are the vacuum ports open allowing air into the engine?  Then the slide might be stuck.  

I did my carb a couple of weeks ago (go for it george, it's not that hard) the routing of all the ports and sub-systems was convoluted, anyway I couldn't follow them all.  Just learn to duck when you spray the cleaner.  There is a number of o-rings and gaskets throughout.  Take your time, print out one of the micro fiche from one of  the parts sites to lay parts on and clean everything.

I wish someone made a rebuild kit like they do for every thing else.  I feel like I'm being raped buying one part at a time.  Of course it was 20 some odd years ago, but I only paid $10 bucks for a VW rebuild kit that included everything.  Now I pay 30 for a freaking needle.  Ouch!