barnesy Posted April 1, 2013 Report Share Posted April 1, 2013 Hi All, After getting my last bike nicked I managed to get a very clean 04 315r a few months ago. It's got a keihin PWK fitted as oppose to the standard dellorto. I've not been able to get out on it for one reason or another until this weekend ... Anyhow I was itching to finally go for a blast on it !! It started fine (second kick) and ran fine on the choke but as soon as I knocked that off the bike would run for a few seconds then die. If I ran it on the choke it would run for a bit longer then die. The only way to then start it would be to bump it off down a hill. Today I've drained the petrol off (as the bile has been standing) and put a fresh tank in. It now runs a lot better, it will run off the choke but it pinks a bit about quarter throttle and the throttle response is not as sharp and clean off the bottom as my old dellorto quipped bike was. Is the bike running a bit lean (to account for pinking) as when the chokes on my old bike used to race a bit until the choke was knocked off as this one doesnt. If so what do I need to fix the mixture !! I dont have a clue about carbs as I never had to do anything with the dellorto equipped bikes. so any advice om setting up the card is greatly appreciated. I was expecting the bike to be have turned into a rocket ship but thats far from the case. Apart from the keihin issue I'm well chuffed, no clutch drag the engines jewel smooth as is the suspension. Ta Guy Quote Link to comment Share on other sites More sharing options...
baldilocks Posted April 1, 2013 Report Share Posted April 1, 2013 glad you have another bike Guy. Keihins are much more sensitive than dellortos. Id start by lowering needle clip. how far out is mixture screw ? Quote Link to comment Share on other sites More sharing options...
bambam_n_chunx Posted April 1, 2013 Report Share Posted April 1, 2013 (edited) Sounds like a blocked pilot jet to me! Edited April 1, 2013 by bambam_n_chunx Quote Link to comment Share on other sites More sharing options...
barnesy Posted April 2, 2013 Author Report Share Posted April 2, 2013 Thanks for the advice fellas.. Im away with work now so it will be a couple of weeks before i can fettle the bike again!! I'll let you know how I get on Cheers Guy Quote Link to comment Share on other sites More sharing options...
chuck4788 Posted April 2, 2013 Report Share Posted April 2, 2013 Record the jetting when you clean the carb, that way you'll have info to help you decide future tuning. Some new GasGas, and others, use the Keihin PWK flat slide so jetting info is available. I have Keihin PWK ready to go onto my '04 315R, just need to find the time. LOL Quote Link to comment Share on other sites More sharing options...
barnesy Posted April 3, 2013 Author Report Share Posted April 3, 2013 Excuse my ignorance but does that mean the various jets have a size stamped on them ? Quote Link to comment Share on other sites More sharing options...
chuck4788 Posted April 3, 2013 Report Share Posted April 3, 2013 (edited) Yes the carb parts are marked, sometimes you'll need a magnifying glass to read them. Genuine Keihin parts also have a copyrighted Keihin logo. Some recommended jets for 250cc Trials use. 122 main 42-45 pilot 3.5 slide JJH needle - middle clip position 1.5 turns out on mixture screw (initial) Do a search in the GasGas, Sherco, and Montesa forums for Keihin PWK carbs. Edited April 3, 2013 by chuck4788 Quote Link to comment Share on other sites More sharing options...
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