Air filter & rejetting

I put a Uni foam filter on my VFR750 and now the power seems to have gone. I'm thinking (hoping) I'm just running lean? What jet kits has anyone used to correct for filters? Stage 1 or 2 kit or something else?

 

stage 1 unless you have a full exhaust. you may simply be able to shim the stock needles and go up a little on the main jet if need be. IMO

 

Thanks. Sounds like a good thing to do when rebuilding the carbs.

 

i have unifilter on one of my '86s, works fine.

did you follow directions?? Use spray filter oil and blot out excess with a rag....

 

Yeah, did all that. I did go kinda light on the oil though. Wasn't sure how much to use. Maybe I went too light? I was having an issue with it not wanting to start in cold weather, and the choke was being a PITA. Maybe its carb cleaning and fuel system maintenance time too.
Will an in-line fuel filter help?

 

should not need to jet the carbs based on just an airfilter. I run a k/n with V/H exhaust with stock jets no problem. I would say that you have carb issues that need to be rebuilt or sync.

 

If you turn on the choke when riding and it helps, you're running lean.

Now whether that's due to not big enough jets, or partially clogged fuel orifices...you have to find out for yourself.

 

I do have issues starting it in the cooler weather. If I turn on the choke, it'll idle at low rpm, but die if you touch the throttle under anything other than choke full off. It seems to take forever to warm up enough to run without the choke off. It sat for a while before I bought it, but I ran it all summer. Starts right up in 80* and up weather.

I think I'll spend the money to redo the carbs, then see how it runs before I do anything else. I have a few months to play with it.

 

Hey man your problem sounds just like my new problem. I cut the dual supertrapps on my 86 and like yours the bike dies when you touch the throttle without the choke fully pulled. Let me know if you find your problem as i will let you know what i find. next i gonna try to sync them. i hope that is the solution since i've tried everything else that i could think of short of taking the carbs off rebuilding. The bike ran great until i cut the exhaust cans. I am interested to see what you find with yours

 

Syncing the carbs is useless unless you know the condition of the carbs.

The order for properly tuning these bikes is:

1. Valve adjust
2. Carb Cleaning/set floats
3. Bench Sync
4. Carb Sync
5. Pilot screw adjust