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77 750f2 Jetting question

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xnatex:
First off Hello to ALL.  Hope everyone is well.

     I'm building a 1977Cb750f SuperSport and I'm thinking of going to Pods instead of the airbox. I've got stock 105 main jets right now, what's the deal with jetting? Is there a way to figure out what I'd need to bump them up to?  I've got a 4-1 Kerker and a stock engine.
Also, other than the obvious benefit of it cleaning up the bike, and just looking pretty bad-ass, is there any benefit to running these?

Thanks in advance,
                    Nate

jvalbuena:
Hey, Nate. Sorry, can't help with the jetting question but I'm just finishing a total rebuild of my '77 F2. I've done a bit of work locating parts and have some good sources. Let me know if you need info about where to get parts for your bike. It can be a bit of a pain to find parts for these bikes ('77 and '78 F2s and F3s).

juan

fergie:
Nate, a motor is really just a big air pump, the more correct air/ fuel mixture you can pass through it in a given time the more power you will have. getting the air fuel mixture correct is critical to your engine running properly and its longevity.by increasing air flow you obviously need too increase fuel.getting it right can be tricky and frustrating and is best done when you have access to a dyno .Start with the main jet,that will get you in the ball park . When increasing jet size always start on the big side and work down.when you get it close then adjust the pilot size.as far as sizes go someone in the group with a 750 would better aswer that question as im a 550 guy. good luck,fergie.

Mr. Grimm:
XNATEX,
I'm in the midst of building a F2 also. I've not ran mine yet, but have read a few opinions on how to callibrate your bike. I'm going stock engine, K&N filter in airbox and likely Mac or modified Mac exhaust. Have 115s in for the start.

If you're running pods on your bike, you'll need to go up 1-2 sizes. After market exhaust another size. Elevation can also play a factor,(Higher up is thinner air-less gas needed, drop 1-2 sizes...lower elev. opposite applies). I would start with a 120 and work to a 115. If you can find one, there's a 117.5 available that might be just what you need. Also if your top end is good, but you lack midrange punch, try adjusting your needle jet clip. If it's adjustable, move the clip down 1-2 steps. This will have the needle jet up higher out of the jet opening allowing more fuel to flow. Hope this helps.

Mr. Grimm:
Forgot to tell you,

If you run pods, only use the K&N brand. All others will have each carb flowing different, making it impossible to synch. They don't straighten the air as it passes into the carb.

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