Is it worth to get a Jetkit for my bike,Will it be any improvement?
Bike is:CBR 1000 F 1997,Stock exhaust,KN-airfilter for now.

 

Are you having throtle issues? Hesitation, flat spot? If so the Dynojet kit will help. If not don't bother.
I installed a Dynojet kit when I added my V&H exhaust system. My bike runs great.

 

waste of money. i bought it, then rejetted the bike with the stock needles and jets and it ran much better. it pulls like a damn train past 8k, even with a 100% open intake (i have no filters or anything, just the carbs open) and a full V&H exhaust. im running about 13.5 AFR up top (yes, i have a wideband o2 gauge on my bike) with the stock jets.

 

ok thanks,i dont bother to buy it then,i just tought that it may be a way to get a little bit more performance.

 

I wouldn't bother either. I fitted a stage 1 kit to mine when I fitted my V&H and K&N. I ended up putting the original springs back in because the new ones were too light. When i cracked the throtte open there was a lag before the power came on. It runs a treat now.

If you fit a free flowing pipe you'll probably need to fiddle with the mixture a bit but, if it runs fine now and isn't lean, spend your hard earned $$ on something else more worthwhile IMO...you know...beer, chicks etc.

 

So in other words, a good tuner can tune the bike properly with just new jets, and won't need a Dynojet kit even though the needles are not adjustable?
Would save me a lot of money, as my bike needs a tune after adding mesh filters and an open exhaust...

 

With what you're describing, stefan, you'll probably need to invest in a kit with adjustable needles. I have a faint memory of somebody shimming the standard ones though.

Whilst it might seem to run ok, if you run it lean (and it probably is with that nice free flow of air) you'll kill it in the long term.

Find a good tuner with all the testing gear and get it set up properly.

Oh yeah stefan; don't tell the other guys I said this but I like the look of your fighter.

 

I'm not telling
And yeah, it's running a bit lean, though I did plug two vacuum ports the previous owner left open, and will gear up in a few minutes to try it out again, see how it runs... but I'm sure it needs a tune, because of the free flowing intake/exhaust.
It idles smoother, so I hope it'll be an improvement.

 

you can add washers to the stock ones to raise them up if you want. it's easy enough.

you really arent going to go much fatter on the jets. im running no intake at all and im still on the stock jets. itll ride like crap if you run it too rich.

 

Well, I'm not doing it myself, will be bringing it into a shop for a good tune