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Discussion Starter #1
So im looking to make some upgrades to my '99 ex500. Its my first bike so im not an expert at all when its come to this, cars are more my thing. But ive been looking at getting a 2-1 exhaust, k&n, stage 3 jet kit and new sprockets, clip-ons. First how hard is it to rejet the carbs? Also, what sprocket should i get to improve take-off? Any help, brands recommendations or info would be appreciated!!!!

thanks
 

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You mentioned some good mods there. I've never needed to do a rejet, since I have my stock exhaust, so I can't comment on that. But as for the sprockets, I can give some advice. If you want faster takeoff, you need one or two of these things:
1. smaller front sprocket. This is cheaper than a rear sprocket, and easier to install. But it makes the chain turn a little tighter, which adds a little extra wear and tear to the chain. Most people will drop one tooth, and a few people will drop two teeth, but that's quite a bit.
2. larger rear sprocket. This is more expensive and a little harder to install. You might need a longer chain, depending on how big you make that sprocket. Most people will go up about 3 teeth or so in the back.

Changing your sprockets (smaller front or larger rear or both) will improve your first gear take-off. But there are three disadvantages. First of all, since first gear revs up faster, you'll hit redline faster. And that means you have to shift to second. So it's not really much better for first gear, since it makes first gear get used up so quickly.

Secondly, changing the sprockets this way also tightens up the gearing. So that means that you'll have to shift more often than you used to, because you'll reach sixth gear quicker. I think that's kind of a pain for city driving.

Thirdly, your highway RPM's will be higher. I think that's also a disadvantage on an already high-revving bike.

If you want to know how much difference you will make with different gears, it's all simple ratios. For instance, if you change a 16 tooth front sprocket to a 15 tooth, that's one tooth difference from 16 teeth. By percentages, that's 1/16 or 6.25% difference. Or to get the same amount of change you could change the rear sprocket from a 42 to a 45. That doesn't sound like much, but you'll sure feel it in first gear. And you'll feel it on the highway.

Personally, I think you can get a bigger difference by just revving the bike higher. That gives you a lot more power (that's power, not gearing), and power is what you need for fast takeoffs. Changing sprockets is playing around with the gearing, but it doesn't add any real power. Some of your other mods do. You might cut 20 pounds off your bike by changing the exhaust and removing the centerstand. And anytime you can get more air (K&N) and more gas (rejet) into your engine, you'll get more power.
Curt
 

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Removing

Remove all the dead weight,,,centerstand and shave some of your rear fender (acting as a drag chute on a funny car), you will lose some serious weight by going to a lighter single exhaust, geting rid of the airbox and going with individual air filters, and get a taller windscreen, the stock one is shorter than a racing one. Get better tires, Metzler, Dunlop there are several great 16" tires now,,,,don't forget to check out Conti...they have a new camapagn going...perhaps mischelin...anything you can to to become more aerodynamic,,,no loose clothes flopping in the breeze, carb rejetting, even changing out the rear sprocket about 3 teeth ...it will equire a longer chain, but it's worth it for bottom end power. Look for anything protruding from the sides or under yoru bike that will mess up/disturb airflow...if you can get by with a couple rubber spacers to push the sides of yor fairing out a bit it will further keep you in the airpocket and out of the flow. Increase yor cold tire pressure byabout 3 pounds and use chalk across the tire to see if you are using the entire tire or not...to much pressure you won't be and to little and you will be scuffing and sliding, that too should be obvious by looking at the chalk mark that it isn't chewed up to the complete edge of the tire ..if it is just right you will have even chalk marks across the tire...be careful and warm them up first. Frame sliders or even handlebar sliders are cheap, although frame sliders are a litle difficult to intsall on a 250R/500R. If you are pretty serious g to a boat/reupholster shop and have them make you a sadddle out of closed cell foam whre it fits you in your length of the seat when you are "IN" position. It may even be lower but that is okay too. You can get the Service manual and adjust he front forks with different weights and amounts of oil, even change the springs in them if you want...but change the seals if you do. Seal any gaps that you may have on the front fairing, that allow the airflow to be disrupted, The usual stuff like lube the chain, frame, wax the bike, use a thinner 100% synthetic oil and change your filter often (whe the oil starts to turn almost dark-dark brown, but before black), and try different brands of gas. Even the same octane will act different in your bike...and get the gas early in the morning, while the ground at depth is still cool. Keep great records of EVERTHING you do. when time day and mileage, even the gas and any weather info that you can keep...see weatherbug...
 

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AND

Some things like smaller profile but legal mirrors, semi-flush turnsignals, shaving even more off of your rear fender...or just unbolting and removing it...you can always just hang a tag from the tail light bolts, and let it swing...Make sure you re torque your swingarm to the proper setting and also your axle bolts need to be checked...they almost always seem to be to tight...and check that the alignment from the rear sprocket to the front sprocket is EXACT. you can do this with a straight edge piece of aluminum, a yardstick, a laser alignment tool...tyhe closer the better, and make sure that you have the proper amount of chain slack. You may get to real close things like resetting the front fender closer to the tire...but things like that wont be noticed on the road...only on a timeclock
 

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larc68 said:
So im looking to make some upgrades to my '99 ex500. Its my first bike so im not an expert at all when its come to this, cars are more my thing. But ive been looking at getting a 2-1 exhaust, k&n, stage 3 jet kit and new sprockets, clip-ons. First how hard is it to rejet the carbs? Also, what sprocket should i get to improve take-off? Any help, brands recommendations or info would be appreciated!!!!

thanks
www.geocities.com/scottbri409/Dynojet.html That is a site I made when i rejetted. The hardest part is getting the carbs off the bike. I have a stage one, but D & D says their exhaust works best with stock air filter and a stage one jet. If you get a dynojet kit, it will have the parts for a 1 or a 3 jet. The pictures on my page will help either way since stage 3 is just a different sized main jet. I noticed a huge difference in power with just a stage 1 and 2-1 exhaust!
 

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Start by dropping the front sprocket 1 tooth. My new sprocket cost $14, and for that amount of money, it was a great improvement. The bike accelerates harder in every gear, responds better on the highway, and the only downside is it is seems to be a little bit noisier, but once you get moving, wind noise is a lot louder anyway.

You lose about 3-5 mph on the top of gears 1 through 3. I don't pay attention to the tops of 4th, 5th and 6th. The bike will still break 40 in first, 60 in 2nd, and falls just shy of 80 in 3rd. As far as cruising on the highway, 75 in 6th goes from about 6200 RPM to about 6500 RPM. It's VERY difficult to notice that. I can't remember what 5th is, but if you like to cruise in 4th at 75, it goes from about 8200 RPM to 8700 RPM. A little more noticable, but if you're willing to cruise down the highway in 4th, I doubt you care :)

Thats stuff I remember from riding the bike, but I calculated it all as well. If I can dig that up, I'll post exact numbers.

As far as feel, I had a friend ride the bike (the person I bought my EX500 from about a year ago) and he could feel a difference as well, so I know it's not just in my head. It makes the bike a lot more fun.
 

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Discussion Starter #7
if i drop a tooth is a new chain required? that little bit of rpm increase wont bother me. where did you get the sprocket from? thanks for the replys everyone...keep them coming..all opinions are welcome..

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I bought the sprocket from my Kawasaki dealer, and it came from a huge parts distributor. If you have a local dealer you like, I would talk to them, or get in touch with the forum sponsor, Beartooth Kawasaki.

If you drop one tooth in the front, you won't need a new chain. I reused mine, based on my dealer's recommendation, and it's working fine.
 

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larc68 said:
if i drop a tooth is a new chain required?
Nope. One tooth matches one link, but when you consider geometry (the chain only contacts half of the sprocket), you would need to change the chain length by less than one link. Since you can't drop one link from a chain (you have to do pairs of links) you can keep the stock chain. If your chain has stretched so much that you are already at the end of your adjuster, then you would need a shorter chain, but if your chain has stretched that much, you are way past the point of needing a new chain anyway.

So to answer your question, you don't need a new chain. Just take up the tiny bit of extra slack by moving the rear wheel back.
Curt
 
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