Hi everyone. So I pulled the trigger on the Bill Blue 351. It should be here in the next day or so. I've been doing all the other stuff to my 09 sf in the meantime. Changed plug, deleted the smog stuff, changed brakes, sprockets and chain. I'm running Fmf mega bomb with the power core 4 and a lidless air box. Not concerned with noise. 15 years (and counting) working on fighter jets rendered me pretty insensitive to that sort of thing. So I've searched high and low on good baseline jetting for my application. I haven't found it yet. The closest I've found is in someone's signature line. He's running a lid with no snorkel, a q4, a 132 main and an N1TC on 2nd clip. Also, Klxster gave his advice. I'm going to write a detailed report with this title so it's searchable in the future. I decided to start with a #40 pilot, N1TC on the 3rd notch, and a 140 main. KLXster seems to have good luck all the way up to a 144 on stock bore. My bike as a stock bore is a 128 main, n1tc on 3rd notch and a 35 pilot and it runs great. Any input from people with prior experience would be great before I stuff this bad Larry back in that tiny hole it lives in. Also, I'm not going to be dyno testing it so I'll have to go off of the plug color, smoke, and the calibrated butt. Hope I can help a few people along the way. Feel free to ask any questions as well.

Edit: current carb setup as follows

This setup has a ton of power all through the rev range with a dead spot at about 6500 rpms. It doesn't lose power, but just goes flat for a second. Then it revs fast up to redline. Best combination so far.


Keihin #40 Pilot Jet
Screw 2 turns out
DJ needle from 2152 kit with clip on 1st notch, 2 washers on top
DJ 148 main jet
Stock spring with drilled slide
Lidless air box, mega bomb, and powercore 4 with spark arrestor


First setup after big bore: runs great up to 7000, then goes flat and doesn't do much above that.
Keihin #40 pilot jet
screw turned 2 turns out
DJ needle from 2152 kit with clip on 3rd notch
DJ 140 main jet
slide drilled

 

I will be watching this thread closely as I just picked up a 351 kit (not installed yet) and will be running my stock carb with snorkel removed and FMF Q4.

 

What is your elevation? If you find the 35 pilot works fine for you now, don't be surprised if the 35 will work with the 351. Bill Blue recommended on up on the pilot (38) and 2 up on the main. I tried the 38 and it was too rich for me so went back to 35.

Search the FAQs for 'spreadsheet.' https://www.kawasakiforums.com/forum...q-links-30733/
You should find an on-line spreadsheet detailing jetting by others.

 

I only know facts and data about fueling with a lidless airbox and performance slipon OR full performance exhaust on a stockbore.

The N1TC is a very short, very aggressive, needle compared to the 2 DJ's. We've measured all aspects of all of them, in here. This means it will tend to run the mid range rich and the top end lean. This is exactly opposite from what is needed. In the above applications, we have found N1TC to operate acceptably, when combined with a proper main jet (DJ140/K152 with slipon, DJ144/K158 with full exhaust system - all near sea level) when used on the top notch with the stock slide spring and lift hole/port.

In most all other applications and clip settings, N1TC would need a "smaller than optimal" main jet in order to not overfuel the mid range - making the top end lean and weak. What we (myself and those that use my findings/recipes) have found is that, once unleashed, the new found midrange and top end power are quite surprising- in fact, unbelievable. Until you experience it, you don't know what you've been missing.

I can think of no reason why a lidless, and "piped" 351, would require anything LESS than its' stockbore counterpart - I can think of some really good reasons why it could require MORE..

 

I apologize. I was under the impression that the n1tc was the dynojet needle. The dynojet needle is what is installed. It's not marked so I guessed. I'm keeping that. Also, I'm in Massachusetts so elevation is no more than 1 or 200 feet.

 

As IDRIDR stated above, if you are to keep the stock carb, Bill recommends one up on the pilot and two up on the main. Everything else should be fine, and would only need minor tuning. Of course it's always going to be trial and error, but if you run into any problems, you can post here or call Bill himself.

 

Ok. Just an update. The previous owner gave me the remainder of the dynojet kit when I got my bike. I bumped the remainder of the parts against the parts listing on the DJ website. I have the 2152 kit so my carb will start with a DJ140 main, #38 pilot, DNO228 needle with dynojet spring and air screw 2 turns out. Ill go from there. Also looks like the slide was drilled.

 

Will be watching with interest, I have a 330 KK kit coming and going to use the stock carb at first.

RIght now 128 main, 35 pilot, 2152 needle at 3N works great on the 250 bore. I will probably swap in the 132 MJ when i put the kit on just to "hopefully" be on the rich side and I'll dial it back from there.

 

Thinking about jetting and stock induction with a larger cylinder bore added. Wondering if KLXSTER has any flow bench data for the stock carb. I am particularly interested in a chart with volumetric flow rate vs. carb slide position expressed as a % of max height. I would think that the carb doesn't know anything about rpm, only vacuum/pressure which is controlled by flow rate at WOT. If the slide can reach full open height then I could see the RPM greater that that which causes the slide to top out will run a lean mixture since no more opening of the needle valve is possible. Or maybe rich as the chocked carb will have an elevated vacuum pressure leading to increased fuel flow through the main jet. If the carb will not reach this choked flow situation with the BB351, and DJ's needle section narrows down from the stock bore's WOT max flow slide height to the reasonably higher slide of a BB351 at WOT max flow then I would deduce that the jetting for a stock bore will have similar F/A ratio as the BB351. So my next question would be how much airflow through the CVK does it take to max the slide height out? Can a BB351 reach this flow rate? Assuming 100% volumetric efficiency the 351 will flow at a little over 7000 rpm what the stock bore flows at 10k. Most folks will not likely pull much over 7 krpm WOT on a BB351 for long periods. So at real riding speeds and situations the stock bore jetting should be OK. Sometimes I think too much.

 

The question is.... do you run @ WOT? When u do, you are out of carb! Well, proabably.

It will run on the CV carb, it RUNNS on the SC.