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Carb settings cb400f with 4-2 exhaust

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Erwin83:
Hi. Sorry if this is the gazillion-th topic on carb settings.

I'm currently overhauling my carbs, and they will go on my standard cb400f (normal air filter etc).
I've replaced my original 4-4 exhaust with a custom 4-2 which I built based on the headers of the 4-4, a custom Y-piece and 2 sporty but not completely open red-tip exhausts.
There are no balance pipes.

I'm wondering if I should deviate from the standard carb settings and jettings.
For instance a different clip height to have a slightly richer mid range?

I've destroyed a 350 engine already once because of too lean mixture. 'D like to avoid another of those  :-[

Any advice?

Tnx

Erwin83:
No-one with a savvy comment or link to information elsewhere on this forum?
 :o

Laverda Dave:
I would go with normal settings for starters. Ride the bike to a dual carriageway, wait for traffic to pass, drop the bike into 2nd or 3rd gear and rev it to max revs for a 1/4 mile and then pull the clutch in and kill the engine at the same time, DONT close the throttle when doing this. Pull over and take the plugs out. If they are sooty the mixture is too rich, grey and it's too lean and you'll need to use a bigger main jet.
Its all trial and error so you'll need a pocketfull of main jets and plenty of time to keep doing plug chops. An alternative is to book a session on a dyno, it might be a quicker option. You are in unchartered territory here making your own pipe so there's no previous data to go on.
Good luck and let us know how it goes.

Erwin83:
OK, got my Taiwanese carb rebuild kit (the one which people seem to be enthusiastic about). Hopefully I'll be able to get it fitted this weekend.
I'm going for the standard jets.

Erwin83:
So, after installing the kit in the carbs, and placing the set back on the bike, the float overflow kept dripping. Quite annoying.
Engine runs immediately by the way with the base settings: standard jets, needle at 3rd position, 3/4 mixture out, synchronization eye-balled at peek-through, float heigth at 22mm (old setting was way-off by the way, at 26-28 mm...).

Took the carbs back off and checked if the float needles worked with compressed air. After setting the floats about 1 mm lower (23 mm), all seems well now.

Unfortunately the Taiwanese O-rings for the float cups seem to grow in size. I think I read something similar about the Keyster kits (brass parts OK, rubber parts NOK).

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