Carb Trouble

I bought a 10k miles 640E with a BST 40 carb that ran fine. I took the carb apart and found the needle was almost worn through so I replaced it with new plastic and metal washers. Bike runs fine except at idle will stall and occasionally die (when stopped at lioght, etc). I messed with the fuel screw with little change. I did notice when I turned the screw all the way in the bike didn't die like I thought it should.

Any Ideas? Want to get it ready to sell.

I got a 5,000 mile 2002 Duke II carb (BST) if you are interested. Nothing wrong carb, removed for a FCR install

PM Sent, sounds like something Id be interested to rule out or confirm that its my carb that is the problem.

Also check the enrichment circuit (BST choke).

I had the stupid plastic nut back out and I was running with

partial enrichment. Also the spring in the enrichment plunger

assembly has been know to come out when the nut backs out.:thumbsup:

Thanks to Thumper996 and his old BST 40 the LC4 is now running great. Didnt even have to touch the jetting. If anyone is interested I have a ton of brand new parts in my old carb for sale. The bike is going to be for sale in the northwest area soon as well.

Please do turn this thread into a wanted/for sale/barter. That goes against the TT TOS and would require the thread to be removed.

After running the bike for a while and warming it up all the way I discovered the problem still exists, at least I feel rairly confident I can rule out the carb. I threw a FCR in it for a while as well with the same problem but I wasn't confident about that because I know they can sometimes take alot of adjustment to make the FCR work right.

Checking the coils next.

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