Tuning my carb help!

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Jmp
Posts: 7
Joined: Sat Mar 11, 2017 11:30 pm
Rides:: 1970 c50

Tuning my carb help!

Post by Jmp » Mon Mar 13, 2017 1:28 pm

Hi, I have a Honda c50 with a race (road legal) exhaust, and the bike is running very lean as expected. There is two screws on my carb, one for idle, and the other the afr. Could I turn the afr screw to make it run a little better, and which way would I turn it? It's a KenJen Japan carb or something like that.
Thanks, JP

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knapdog
Posts: 3927
Joined: Mon Oct 22, 2012 12:51 pm
Rides:: '95 C90 e/s, '11 CB1300, '09 NT700
Location: Barry, Vale of Glamorgan, Wales

Re: Tuning my carb help!

Post by knapdog » Mon Mar 13, 2017 2:09 pm

That'll probably be a Keihin though it may be a copy.
Im very general terms, the idle mix screw on the left you should turn inwards for richness and outwards for lean.
1 1/2 turns outwards should give you the "norm" but every set up is different due to the size and condition of the jets,
etc etc.

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Diesel Dave
Posts: 10667
Joined: Tue Oct 13, 2009 7:25 pm
Rides:: 1965 Enfield Diesel, 2017 Sterling, Modenas Kriss and CT200 - the only Cub left
Location: Brentwood, Essex

Re: Tuning my carb help!

Post by Diesel Dave » Mon Mar 13, 2017 3:28 pm

Jmp wrote:Hi, I have a Honda c50 with a race (road legal) exhaust, and the bike is running very lean as expected. There is two screws on my carb, one for idle, and the other the afr. Could I turn the afr screw to make it run a little better, and which way would I turn it? It's a KenJen Japan carb or something like that.
Thanks, JP
The other screw is the IDLE mixture setting - doesn't change anything else.

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