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Discussion Starter · #1 · (Edited)
Purchased my 97 CBR900 last August with 7800 miles on it for a good price. I knew when I purchased it that first to second gear shift was rough and that it would would need a proper jetting because of the full micron exhaust. The bike was in mint condition other wise so I didn't mind. So I road her easy through the end of last riding season and even though it killed me to do so (I ride all year around) I put the bike in the garage for the winter months to do the repairs.

I pulled the pan and found a bent left shift fork and damaged shift drum. This explained the rough shift between first and second. I also pulled the carbs off and found that the only thing the previous owner had done to them was add some dyno jet mains and shimmed the stock needles a little. Thus explaining the bikes overall lean condition and surging at cruise speeds. I have used dyno jet kits in the past and was not impressed with them so I decided to purchase a Factory Pro jet kit and while I was replacing the trans parts I also decided to throw in one of their evo shift kits.

Yesterday was my first chance to get the bike out with the new upgrades. Wow what a difference. I will start with the shift kit. The kit comes with a heavier detent arm spring, detent arm with micro ball bearing, and new shift star with improved ramp profiles over stock. All these parts are of high quality and are superior to all the Honda parts they are designed to replace. After comparing the Honda parts to the Factory Pro parts I can see why the CBR900s have so many problems with missed shifts and damaged trans parts. All these little parts add up to a huge difference. The shift now through all the gears is faster and more precise. The shift is a little stiffer with the heavier spring but it only takes a fraction of the movement that it use to now when shifting. A light push on the shifter and you get a quick and positive shift. There is no mistaking that it is in the next gear. Unless you have no skill what so ever at shifting a bike this kit will totally eliminate any missed shifts. The kit is a little pricey and can run any where between $179-$199 depending on where you purchase it from. However when you consider the work and expense it takes to drop the pan and replace the shift drum, shift forks, or even gears it is well worth the money.

One thing that drew me to the Factory pro jet kit was that they use OEM jets in all of their kits and there is no drilling of the slides required. Dyno jet on the other hand produces its own jets (which I feel are inferior to OEM Keihin and Mikuni jets) and you have to drill the carb slides to use their kit. Since the slides for a CBR900 cost $114 each I don't see this as a good option. I purchased the factory pro 1.0 or config 10 standard kit which would be like a stage one Dyno jet kit. The kit comes with 2 each of 120,122,125 and 128 main jets. The jets along with the stock ones that are already in your carbs give a wide range of flexibility when rejetting your bike. The needles look very similiar to honda stock needles except that they have groves to allow you to raise or lower them as needed to dial in the carbs. They fit in the slides as if they were OEM Honda needles unlike the Dyno jet kits that I have used in the past that moved around in the slides and led to the needles wearing prematurely. The kit also includes a very nice D wrench that is used to adjust the pilot screws on Honda carbs that is also far superior to the one that comes with the dyno jet kit. Kit also includes 4 extra e clips for the needles just in case you lose one of those little suckers.

The kit also includes sample installations from around the U.S. to help you find a good baseline to start tuning your carbs with. The list has such info as which state, what elevation, humidity, what type of exhaust was on the bike and so on when it was jetted that helps greatly if you have never jetted a bike before. I am running all stock except for a full micron SS race exhaust. I instaled 120 mains in the outside carbs and 122 mains in the inner carbs. I put the clips in the needles on the third slot from the top and set my pilot screws at three turns out. My main jet selection was perfect the bike pulls like crazy now from around 7000-7500 all the way up to redline at full throttle. The front end gets light really quick now which didnt happen before I installed the kit. My needle selection which was recommended by the kit seems to be a little on the rich side so I plan on raising the clips a slot to help clean up the midrange at full throttle. As for the three turns out on the pilot screws it seems to be rigt on as well. My surging problem at cruise and my hard starts in cold weather are now a thing of the past. The bike idles smoothly now and sounds like a beast. Once I get the right slot on the needles and get the midrange dialed in the fueling will be perfect.

I highly recommend both the Evo shift kit and the 1.0 or config. 10 jet kit. They are both high quality items and well worth the money. Well I am off to get in some more riding before I get hit by another snow storm.:D
 

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Discussion Starter · #5 ·
No I have not. From what I know about the airbox plus kit you need more than a stock motor to get any real benefit from it. Personally I believe in using OEM air filters on a street bike that has no mods other than a slip on or full race exhaust like my bike has. Now if you had aftermarket cams, a ported head and had the cylinders bored to a bigger size I would say give it a try. Because then the motor would probably be able to suck in more air than the OEM filter could provide. Another drawback that I see to the plus kit is the material they use to actually filter the air. It doesn't look like it would offer much protection against dirt and dust that an everyday street bike has to endure.
 

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Discussion Starter · #7 ·
The only benefit that I see to K&N for an everyday stock street bike is that you can clean and reuse it. However these filters can make tuning a bike a little tricky if you don't have experience with jetting carbs. I also believe that the K&N and other aftermarket filters that allow the engine to take in more air also allow more dust and dirt to enter the engine. Now for a race bike this may not be a concern but for a street bike that gets used everyday this can cause premature engine wear.

I am a firm believer in using all OEM filters on my bikes. Honda has been building and racing motorcycles for a long time and they have a reputation for building a bike that lasts. So I trust their choice in filters. So even if the K&N made 2-5 more HP or whatever it is they claim it is not worth the wear and tear on the engine in my opinion.

If you are looking to get a little more performance out of your 900 replace the stock sprockets. Try going -1 tooth in the front and +2 in the rear. This will briing new live to your old bike.:thumb:
 

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Discussion Starter · #9 ·
With -1/+2 you will probably lose about 15 mph of your current top speed. I don't know about you but I rarely see tripple digit speeds on public roads so I could careless about that 15 mph at the top end. The increased acceleration through the gears and out of the corners is well worth the trade off for me.
 

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Discussion Starter · #11 ·
dont forget that this will also increase the inaccuracy of your speedo to about 15% but this is the gearing i have on my 900 and its makes it a lot faster out of the hole. and it will even get very light in second.
That is why I have a V4 speedo healer on my bike.:thumb: I know it doesn't make the speedo perfect but at least its back to factory accuracy :D
 
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