shercoman2k8 Posted September 5, 2009 Report Share Posted September 5, 2009 (edited) Well, basically found a carb off an old gasser lying in a mates shed, on closer inspection it turned out to be a keihin flatside! Offered to buy it from him and he said a tenner and its yours, its only gonna lie there otherwise. It seems to be in great condition and is now stripped on my bench being cleaned out properly. Just gonna try it out on my 125 before deciding wether to keep it or ebay it. Just a quick query on jetting though, best base point? My sherco's pretty much basic apart from the standard paxau modifications. The bike it came off was a 125 gasser with ti frontpipe, high comp head and piston and a load of other little goodies, im guessing the jettings gonna be way out for a straight over transfer? Its a pwk28 Help please (Copey, I see your online?) Regards, Jamie Edit: Hows 118, 45 sound? Probably go down one on the pilot? Edited September 5, 2009 by shercoman2k8 Quote Link to comment Share on other sites More sharing options...
copemech Posted September 5, 2009 Report Share Posted September 5, 2009 Well, basically found a carb off an old gasser lying in a mates shed, on closer inspection it turned out to be a keihin flatside! Offered to buy it from him and he said a tenner and its yours, its only gonna lie there otherwise. It seems to be in great condition and is now stripped on my bench being cleaned out properly. Just gonna try it out on my 125 before deciding wether to keep it or ebay it. Just a quick query on jetting though, best base point? My sherco's pretty much basic apart from the standard paxau modifications. The bike it came off was a 125 gasser with ti frontpipe, high comp head and piston and a load of other little goodies, im guessing the jettings gonna be way out for a straight over transfer? Its a pwk28 Help please (Copey, I see your online?) Regards, Jamie Edit: Hows 118, 45 sound? Probably go down one on the pilot? Sounds about right to me, JJH needle? Some others have their prefs for the bigger bikes, but the 125 seems less sensitive. Now all you have to do is somehow figure out just how to cram the thing in there. I do not care for the fit against the cases. And I shall restate"If Paxau had liked them, there would already be one on it!". Play with it if you like, yet I suspect you may go back! Quote Link to comment Share on other sites More sharing options...
shercoman2k8 Posted September 5, 2009 Author Report Share Posted September 5, 2009 Sounds about right to me, JJH needle? Some others have their prefs for the bigger bikes, but the 125 seems less sensitive. Now all you have to do is somehow figure out just how to cram the thing in there. I do not care for the fit against the cases. And I shall restate"If Paxau had liked them, there would already be one on it!". Play with it if you like, yet I suspect you may go back! Yes, JJH... the carb has had the bowl ground already, and some foam attached so it should slot in with a bit of effort. I suspect I may go back as with the 28mm you lose some bottom end, made up for by top end power... Just thought i'd experiment as i seem to use my top end a lot more, normally revving a lot. A lot of the 125 riders seem to be using the keihin round here and getting on with it so Im going to give it a shot myself, although I beleive you cant beat a well setup dellorto! Will report back sunday evening/monday morning. Quote Link to comment Share on other sites More sharing options...
baldilocks Posted September 5, 2009 Report Share Posted September 5, 2009 I think you'll need a spacer to move the inlet back Chris at Splatshop should be able to help Quote Link to comment Share on other sites More sharing options...
sdeane01 Posted September 6, 2009 Report Share Posted September 6, 2009 What jets with a 290 sherco then. it is an 08 and i have the JJH needle as well. I have the 48, 120 currently and it is running so bad!! Quote Link to comment Share on other sites More sharing options...
shercoman2k8 Posted September 6, 2009 Author Report Share Posted September 6, 2009 What jets with a 290 sherco then. it is an 08 and i have the JJH needle as well. I have the 48, 120 currently and it is running so bad!! Describe your problem, could be something else? Not sure of the jetting for the 290 though, but will go through everything else if you describe what your experiencing. Quote Link to comment Share on other sites More sharing options...
sdeane01 Posted September 6, 2009 Report Share Posted September 6, 2009 sounds like it is running out of petrol and it pings at high revs. To keep it from stalling the mixture screw is nearly all the way in. if i wind this screw out it gets even worse. tried a new plug and the needle clip is in the middle position. Quote Link to comment Share on other sites More sharing options...
shercoman2k8 Posted September 6, 2009 Author Report Share Posted September 6, 2009 45-48 pilot, 125 main, 3.5 slide, JJH needle and middle clip position. Air screw wants to be about 3/4 to 1 1/4 turns out depending on conditions. Quote Link to comment Share on other sites More sharing options...
copemech Posted September 7, 2009 Report Share Posted September 7, 2009 sounds like it is running out of petrol and it pings at high revs. To keep it from stalling the mixture screw is nearly all the way in. if i wind this screw out it gets even worse. tried a new plug and the needle clip is in the middle position. Sounds as though a good cleaning would be a start! As per the original question, these things do not really seem to vary much on jetting between a 125,250 or a 2.9., or even a Gasser. They just apply fuel for a given amount of air. Revving out cleanly on a 125 can be more critical, as they operate more at those rpm's, therfore the main jet would be more critical. Quote Link to comment Share on other sites More sharing options...
sdeane01 Posted September 7, 2009 Report Share Posted September 7, 2009 I have cleaned it out with the air compressor, changed the fuel and the tank has been cleaned. I do runn an in line filter and maybe that needs to be replaced or not used at all Quote Link to comment Share on other sites More sharing options...
trialsnutterman Posted September 7, 2009 Report Share Posted September 7, 2009 When I got my 08 bike I had to lift the needle a notch i.e move the clip down one from the middle. In the UK I nearly always run a larger main i.e. a 125 in winter and a 122 in the summer but you may need the 120 with you been in Australia. I also have always run a number 4 slide but they are quite expensive and they don't make a huge amount of difference. I'd start off by giving your carb a proper good cleaning, remove all the jets, the mixture screw, the main jet holder and the little needle jet behind this. Then use some carb cleaner to flush all the passages out before blowing clean with a air line, now do the same with all the parts you have taken off, hold all the jets up to a light to make sure they are clear, oh and make sure your hands are clean and all the tools you are using. If your still having problems check the float height, I've always run mine a bit high as I never found a good explanation of where or how it should be measured, then at the SSDT one of the Sherco factory mechanics was cleaning my carb I noticed he made the float level lower, end result my bike was pinging like hell all day, way too lean so rightly or wrongly it had to be put back to how I had it before, since then I've lowered the level and re-jetted it to suit. Quote Link to comment Share on other sites More sharing options...
shercoman2k8 Posted September 7, 2009 Author Report Share Posted September 7, 2009 Set it up tonight, got it on the bike after an hour or two of trying, fitted the cable, adjusted it and I must say, it's amazing! Very fast throttle response, I noticed a bit more bottom end, aswell as lots of top end, shoved her in fourth on the track, opened her out and it accelerated as if in third. Lots of power! Very fiddly though! Beats the Dellorto hands down! Quote Link to comment Share on other sites More sharing options...
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