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DynoJet jet kit


Mr.XXBlackbird

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I managed to access the needles and main jets without removing the carbs. You will need to remove the seat, tank, and side trim pieces (necessitates loosening the side fairings). Remove the airbox.

The needles are accessed by removing the 3 screws that hold the black covers on the top of each carb. The choke mechanism makes access to a couple of the screws a little tricky, but it's doable. Remove the carb top and spring to reveal the diaphram. Pull the diaphram and needle free. Now take one of the screws you just removed and thread it into the top of the needle holder (you'll notice it is threaded). While holding the slide/diaphram assembly firmly, grip the screw with a pair of pliers and pull the needle retainer free. Turn the slide upside down and the needle will fall free.

To access the main jets, remove the float bowl for each carb. Again, there is 3 screws which can be accessed by using one of those phillips screwdriver bits in a socket attachment (not enough room to get a screwdriver in there). This will expose the floats. In the center of the assembly you will notice a hex-headed brass piece, with a slotted brass piece screwed into it. The slotted piece is the main jet, the hex piece is the needle 'jet'. Using a slotted screwdriver bit, you should be able to remove the main jets..

Install in reverse order (obviously).

-Pace

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OMG :!: Once you have the airbox off just pull the carbs, very easy. I can't imagine doing it with the carbs installed.

The job is easy, it's the 3 or more times you must do it to get it right.

Your fuel mileage will also suffer about 10 mpg. :cry:

I did it, didn't like the mpg loss and put it back to stock. The biggest improvement is the drilling of the slides (if needed) and turning pilot screws out 2 1/2 turns. Don't need the kit for this. :wink:

On the dyno I could see a slight improvement but seat of the pants none.

If you put on (or have) a pipe, that could change.

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I did it, didn't like the mpg loss and put it back to stock

I don't know, maybe it's just me but I couldn't give a rip about mpg loss.

If it made 200 horses and got 5 mpg, that would be fine with me. Remember, you can't have your cake and eat it too.

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OMG :!:  Once you have the airbox off just pull the carbs, very easy.  I can't imagine doing it with the carbs installed.

The job is easy, it's the 3 or more times you must do it to get it right.

Your fuel mileage will also suffer about 10 mpg. :cry:  

I did it, didn't like the mpg loss and put it back to stock.  The biggest improvement is the drilling of the slides (if needed) and turning pilot screws out 2 1/2 turns.  Don't need the kit for this.  :wink:  

On the dyno I could see a slight improvement but seat of the pants none.

If you put on (or have) a pipe, that could change.

So that's where my gas mileage went :sad: . I bought mine already jetted with pipes. Couldn't believe that I was only getting 25-32mph.

I wouldn't want to screw with it now though. The power is great, and it run tits.

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I did the dynojet kit and kept the stock pipes on my '98. After the seventh settings change I got it down to 45 minutes from seat off to seat on, so it really isn't very hard to do at all.

Mileage wise I went from 200 miles before the low fuel light comes on to 175 miles before the warning (of course, this presumes sane and not blatantly illegal speeds - spend extended time in the triple digit range and your mileage may vary, alot!)

And regarding performance, the two most noticable improvements are that the throttle response is much more crisp and instantaneous, and that the "top end afterburner" now ignites around 5000 rpms instead of the previous 6500 rpms. Also, although I don't have the dyno numbers to prove it, the acceleration seems to be improved throughout the range, but especially from 5000 to about 7500 rpms.

Another, more aesthetic improvement relates to the K&N filter I installed. It really changed the sound of the bike under hard acceleration. Its really cool and alot cheaper than pipes. But BEWARE of the K&N out of the box. They put WAY TOO MUCH oil on them and you should clean off the oil and reapply a very thin coat. Otherwise you will find that as you run the bike for the first 1000 miles or so, the filter will gradually breathe better and make your mixture gradually more and more lean. Trust me on this!

Over all, my rating of the jet kit mod is that it is definitely worth doing, but it can be very frustrating and requires alot of patience to finally get it right!

One final word of advice, if you are going to do this mod replace all the carb phillips screws with allen screws. Otherwise you will be stripping phillips heads after about the third or fourth iteration.

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Right... I can change all needle settings in about 30-45 minutes from start to finish now. No need to pull the carbs at all..

My problem with stripping screw heads is mainly with the airbox-to-carb clamps. I noted that two of them are getting really chewed up. After 5 jetting changes, my carb screws are still holding up ok (with one exception). :wink:

-Pace

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OMG :!: Once you have the airbox off just pull the carbs, very easy. I can't imagine doing it with the carbs installed.

I have to agree. since your already there. Remove the carbs.

I have also found the pilot screw original setings from the factory

were off by as much as 3/4 turn differance from carb to carb.

My .02 cents, Cal

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Remember,  you can't have your cake and eat it too.

That's funny. I just got an email about five minutes ago that said, "what's the point of having cake if you can't eat it?"

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I've heard to stay away from the DynoJet jetkits; from more than one source! I can't remember the reasons.

I just got a Factory jetkit installed a couple days ago. Today was the first chance I got to test it out. It feels so much smoother!

MJP 2000 dyno:

135.98 max hp

86.11 max ft lbs

11102 max rpm

1.098 sae j1349 corr f

2 brothers slip-ons

factory jetkit

Strange thing, though. I know I wasn't pushing her very hard today, but I expected to see a mileage drop from the rejet. Instead, I'm getting about 5mpg more!! WTF?!

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In order to "eat" my cake, the first step would naturally be to "have" it. :lol:

Yeah, I don't know what was up with that mileage increase. Perhaps, the accuracy of the pump's meter is off? I dunno. I'll run a few more tanks and keep ya posted.

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