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splatered stu

any Keihin carb tips? whats the air screw set at?

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122 or 125 main

45 or 48 pilot

Air screw 0.75 to 2.5 turns out depending on the above and atmospheric conditions.

 

 

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first thing first ,make shure the carb is clean . pilot jet prone to blocking and will make engine hunt on idle , other thing is float hight it is very easy to knock out of adjustment when removing and fitting the float bowl . factory jetting is ok for uk , some fit number 3 slide for a bit more zip at bottom end but that is a personal choice . as above about 1.5 turns out a good place to start , go a bit at a time to get it running smooth and look at the spark plug to see for a nice colour. hope this helps a little

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i cleaned the carb as it was not starting due to lack of fuel...it seemed to clear up except one time i had to tip the bike over till it dribbled out of the overflow to start it again it was not getting fuel.seems alright now ,maybe a little hard to start when cold.need more than 4 kicks sometimes.I'll try those settings and see if it helps.how does one check float height on this carb? i do mikuni's by eyeball but not sure of how this is supposed to look when dialed.thanks guys,this helps lots.

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When running well, to set the idle I’m for the smoothest and slowest achievable idle, then just increase the idle speed a 100 rpm or so which should prevent stalling. You may have to add a few more rpm but make sure that on downhills the engine doesn’t stop (throttle closed) as when you get it  to fire up again it will have put you off line. Don’t forget to blip the throttle with clutch in to prevent nipping of the rings.

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Keihin specs 18.5 mm for setting the float height if you have a reliable caliper or float measurement tool to set it. It's nearly impossible to set 0.5mm so either go with 18 or 19. It is important to set your float height correctly before attempting any jetting changes as the level of fuel in the carb effects all of it.

Make sure when setting that the carb is tilted so that the float tang that contacts the needle just touches the needle without compressing it.

Before doing this make sure the needle and its seat are clean and without grooves or wear otherwise replace them first before measuring. 

Splatshop has a good section on visually setting the floats here:

https://www.splatshop.co.uk/blog/2012/12/setting-the-float-height-on-the-keihin-pwk-28/

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excellent...good stuff guys.as of yet i have not been able to download any sort of manual on this bike.but this works for me....looks like I'll be busy in the shop this weekend.thanks so much for the information.

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