Topic: Baseline jetting suggestions?

[Mattydiah]

Well, I finally got a full Kerker system today.  No dents, no holes, just some surface rust.  70 bucks!!!  Not a bad deal, I'd say.

Anyways, I'll be running that kerker with the stock airbox, but with a Uni foam filter inside it.

The bike, a 77 CB750K, currently has stock jetting.  Any ideas where I should be for jetting with this setup?

[hapsh]

It should not make much difference. However if you want to know for sure I would do a plug chop before you change pipes and then after.  That way you can see if there is any difference.  I would do the plug chop after cruising at around 40-60 mph.  You can just do one plug to make it easy.

[pddpimp]

Yeah, test and tune is the way to go. The Carb FAQ board has a lot of useful info on jetting.
Everything matters on a carb tune:
Air filter: Stock, K&N, or pod filter
Exhaust: Stock, 4-2, 4-1, which baffle you have in your Kerker
Timing, Valve setting, Cam chain tension, float height, make sure idle jet is clean, and carb sync are also very important.
Get all of that tuned in and then go for broke.

Just for reference, I have a 77 750 K, stock motor, 4-1 with supertrapp, no defusers in the muffler, K&N filter in a stock box, box has (4) 2" holes drilled in the back of it, Dyna S ignition, stock coils, stock valve setting and timing. I have 135 main jets and Im at the second to bottom clip on the needles. Im also a @900ft elevation.

Carbs are fun, but can also be a headache. Good luck and have fun.

[Vinylwasp]

Here's some handy information on Pipe rejetting: http://www.motorcycleproject.com/motorcycle/text/cows-jetting.html

It's a good read.

There's a really long thread which discusses the pro's and con's of Pods vs Airboxs in the forums here too that's really worth reading if you're thinking of buying some pods.

[333]

Another factor is that older Kerkers had a selection of baffles, ranging from mild to radical.  I agree on the plug chop.  It's the only way to know for sure.