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Tuning 1975 cb750f with pods

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youngmr99

Tuning 1975 cb750f with pods

Hello, Im not sure if this has been asked.

I have a 75 CB750F, I've taken off the air box and installed Uni's pod filters. I currently have the stock main 105 jets and 40 slow jets installed.

Does anyone have any recommendations of the "proper" jets need to make it run better. I have read other things and there were suggestions of moving to a 120 or 122.5. Just thought that was a huge jump?

Thanks

Re-run

Re: Tuning 1975 cb750f with pods

Administrator

Ultimately, there is no "right" jet size. On the older carbs like yours, the mains increased but so did the idle jets. If you are at a lower elevation, then I could see 120 mains and increasing the idle jets to 45.

Higher altitude might require a 110 main with no initial change in idle jets.

You can do some searching here, just make sure you find out if it is a sohc or dohc. Their carbs are different.

The ride IS the adventure. The destination is just to get gas!

TOOLS1

Re: Tuning 1975 cb750f with pods

Administrator

In reply to this post by youngmr99

Since it is a "75" it should have the "Roundtop" carbs. 120 mains are not really that big when you consider the difference between the gas of 1975, and the crap they call gas today. The stock 105's will barley keep the bike running with today's gas.
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shinyribs

Re: Tuning 1975 cb750f with pods

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125's and 42's seems to be a really common setup with pods on roundtops.

One size fits all? Of course not, but its darn close.

youngmr99

Re: Tuning 1975 cb750f with pods

Thanks for all of the responses.

I'm at 2000 ft above sea level in Spokane WA.

Yes the are the roundtop carbs of SOHC bike.

Sounds like my assumptions about going bigger are wrong. I was not aware that I may have to change the slow jets to a 42.

Will get some mains and slows order.

I will update once I get some results.

Thanks again!!!