Board index Flathead Power-Technical Questions, Answers, and Suggestions Knuckles Adjustment of carb

Adjustment of carb

Moderators: Curt!, Pa

Post Sun Jul 07, 2013 8:22 am

Posts: 161
Location: Radolfzell, Germany

Got my Knuckle engine back from the builder. Installed carb (M74B with Cotten's float and peek rings), manifold pressure tested. Bike starts but i need to bring the idle needle down to 1-1,5 turns only, to idle smoothly and take gas nicely when turning the throttle. Bike takes off in first gear but cannot shift to second gear since bike doesnt take gas anymore ... Hardly brought the bike back home (anyway, was only a couple of meters). Bike starts afterwards but doesnt idle anymore properly, shoots quite nicely through the exhaust ...
Any help is appreciated.

Post Tue Jul 16, 2013 5:26 pm

Posts: 530
Location: Ogden, Utah, USA
Oh boy! Been there and did that. Try these things: Drop bowl and see if the jet is blocked, see if the atomizer tube is blocked, See if the float is properly set for height and offset. Make sure the spring is good, see if there is a bit of dirt holding the needle in the closed position. Put the fuel to the "on" position and see if it comes out the needle seat OK. Look for a Non-vented cap on the gas tank. Make sure the jet is the right size. Make sure the timing is good and point gap is right. Now that you have something to do for a few days, Enjoy!
Steve H

Post Tue Jul 16, 2013 7:16 pm

Posts: 159
And try another condensor.

Return to Knuckles