Topic: 1975 cb 400f air filter questions

[Ban the Dead]

It came with air pods installed. If i go back to the stock air because i live in Florida and wanna ride in the rain, Do i need to change my jets or just tinker with idle/air?

What's a good air filter if i go back to stock?

[jneuf]

Did you find out if the previous owner had re-jetted for the pods?

[camelman]

If you have stock exhaust, then stock jets are correct. Plenty of folks on this forum have spare stock parts for that airbox if you need.

[Ban the Dead]

Yeah stock exhaust. I'm probably just gonna take the carbs off sometime this week and clean em. Minus well while they're easy to get at. Then i'll see what i need for the stock air filter.

[swan]

See what size main and idle jet are in there now. With a stock airbox, filter, headers and mufflers the jets should be #75 main and #40 idle. Most people install a larger main jet (#80 or larger)  and drop down to a #38 on the idle with pods installed. Often the needle clip is changed with pods, so you will need to put or confirm the needle clip in the middle position for use with stock confirguration.

I have built several CB400F's with both stock and pods filters and have learned one extremely important detail, use only HONDA OEM carb parts. The quality control and materials of the aftermarket carb kits are poor and cause all kinds of problems when tuning your carbs. Very frustrating and time consuming. Do it right the first time. Good luck and post your results.

[Ban the Dead]

So far one of the main jets is 75 and idle is 40. Is this useble for pods? Or do I have to get 80s?

[Bodi]

There's a big difference between "usable" and ideal.
If you're OK with how the bike runs then this is usable.
I expect you have a stumble off idle, surging at low-mid throttle, and a rather hot engine after highway riding with those jets and K&N pods. Some other pods are rather restrictive though and don't lean out at high throttle as much.
Those are the stock jet sizes for stock intake and exhaust, but the needle clip may have been adjusted for the pods.

I have pods and although I tend to avoid rain riding, I've never had any problem with rain even torrential downpours where I was just trying to find a bridge to stop under.

[Ban the Dead]

Yeah I'll probably just keep em until next summer. It barely rains anymore down here anyway I can use pods until I find air filters for stock. But I guess I'll go get 4 80 main jets then. About how much is that gonna be? And should I get 38 idle like overheard other people do or just keep em at 40? Anyone wanna link me to a good jet place?

[swan]

Honda, Jetsrus, David Silver Spares and www.siriusconinc.com have them. I recommend jets from Honda.