Ah ok, I completely misunderstood jetting. So does changing the "tightness" of the actual part that screws in change the A/F mixture? Like when I changed the smaller low speed screw?

I have a feeling I might just be a little picky. Really, my bike drives pretty great. I just forget sometimes that its only a couple years younger than I am. There are sure to be some quirks on an 18 year old bike.

Also, one question I really would like answered. When I am testing my carbs and accelerating from 2k rpms, should I just twist the throttle all the way as fast as I can, or give it gas as my engine "takes" it? Should I be able to just twist it wide open before my motor can catch up without it bogging? Thanks so much, i'm learning a lot from your novel that is your brain. lol

 

I can't answer that, honestly. On both my F3 and now my F4i, if I go from dead stop to WOT (wide open throttle), I'm going up on 1. And I don't do wheelies

Oh and forgot, tightening / loosing the main jet won't do anything. Unless you overtighten it, which would be bad. AF mix is done with the D shaped screw (mostly at idle and a little bit of low speed), jet size and needle height. And that's a bit more (a lot actually) than tossing in a jetkit and riding off into the sun if you want to do it right. Different parts of the jet system affect the AF mix at different throttle positions.

Rather than re-write the book, take a read of this: Carb Tuning Guide - Symptoms and Troubleshooting

 

That was incredibly useful. So I guess the right thing would be to check if my main jet is the right size?

I started in second and accelerate from 3k rpm to 10k rpm then let it off and come down on its own. Is it normal for it to pop and backfire when letting it come down from such high rpms? It ****ing rips from 6k to 12k rpms, but when I let off it does backfire a bit.

 

Alright, after rereading that link and http://www.factorypro.com/tech_tunin...m_engines.html i'm gonna go into it again tonight and change a couple things assuming my main jet is within 2 sizes- which I think it is.

My float bowl level is set to too high, which is rich. I need to lower it 1mm. And I think my idle and low rpm cruise (d shaped screws) are too rich as well. I don't know if I should just change my float level, then see how it is, or go ahead and change both.

Also, how important is it that my air filter is oiled? On it, it says to never use it un oiled. And what type of oil?

Thanks

 

Err... ok we're getting deep in now. First out: Carb tuning is impossible over the net. 2nd I think one of the first things I sauce was check your air filter. 3rd if your air filter has to be oiled, its an aftermarket air filter.

Have you done any mods recently to your bike? Any changes to the exhaust or air systems can cause problems if the bike wasn't tuned. 2nd if you suspect a rich condition and you haven't changed anything then its NOT a rejetting issue. It's most likely a basic maintenance issue. Which is checking the air filter & hoses. And making sure the carbs are clean and synced.

You may be overcomplicating things here. IF you're gonna attempt tuning your bike, first you must get the basics out of the way. Filter, clean and sync the carbs. Then as that guide I posted said , you do 1 thing at a time.

 

I have done nothing to my engine or intake since the last 3 years ive owned the bike. The carbs are clean, it is driven quite often. It came with a K and N filter and full muzzy exhaust. I am not sure if it had a jet kit put in or not. I have it apart now and could check I guess, but I don't know what to look for to tell if it's OEM or not.

I am wondering how you change the float levels? Wasn't sure if I should make a new topic or not. I took the floats out and the little rubber cone/ slider that seats in the tube. Can I just put a shim in between where the float connects to the rubber cone thing? Would that raise or lower the float level?

lol, yeah I guess asking lein or rich over the internet is sorta dumb. I am pretty sure my main jet is good though, which is why I am now going to tinker with the float level then if necessary, the idle/ low speed level. I think with a K and N filter and a full exhaust, there would have to be a jet kit to be running so well in the top end? I should call the old owner, I think I still have his number.

So yeah, how should I go about fiddling with my float levels?

Thanks a ton for all the help. I'm learning a lot.

 

Don't think you can adjust the float levels on the f2. I know you can't on the f3.

 

You can't adjust float levels. You can adjust needle position.

In all honesty though, you don't know what you're getting yourself into. You're taking blind shots into the dark. Get the thing on a dyno, or get a proper A/F reading across your entire power band so you know what's going on. Bring the document here and then we can let you know what's probably going on. Also anyone at a dyno aughta be able to give you advice. Cost is $60 or so for a dyno run, and well worth it if you got o sell it in the future.

 

Yeah, I decided not to dick around with the float levels. I seem to have plenty of power throughout my RPMs, I think I just need to sync my carbs. It's been 25k miles with no carb sync whatsoever. I am getting bad gas mileage, running hot, and jolts about in the lower/ idling RPMs. I really didn't even think about it, but all signs point to needing a carb sync. Once my bike cools down, i'm gonna start it and try and feel the headers. Now I just have to get my hands on some carb synch adapters. You may have seen my other thread I started... (im hogging this site right now lol)

I brought my one vacuum plug to my honda dealer and the kid obviously didn't know his way around their computer interface. He said he "couldn't find it". I'm not sure where to go to get a good fitting vacuum plug? Does it even have to fit that well? I would think as long as it's air tight, its fine considering its being sucked on. I really only need one more because i'll just sync two at a time. Not sure what I should do here.

 

update?