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Discussion Starter #1
out of curiosity, how would i go about going down a few teeth in the back or (up in the front i guess)?

ultimately i want to learn how to wheelie, but my kat doesn't have enough power stock.

this once again is a research project :). im not planning to do it till way later this summer..

thanks
-d
 

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First, you have your tooth arrangement backwards... ;)

For more pull you can:
1) Go up teeth in the rear.
2) Go down teeth in the front.

As a general rule one tooth down in the front is approximately equal to going 3 teeth up in the rear.

Which one to do is debatable. Some say going down one tooth in the front causes undo chain wear as the radius of the turn is decreased a fair amount. I'd say one may be safe, I wouldn't go two.

Whatever you do, another general rule of thumb is replace the chain, front and rear sprocket together, this way they wear evenly.

Jim.
 

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And now that you're straight on which way to go.....

If you're going to need a new set soon anyway the best way is to go with the larger rear. 2 or 3 teeth makes quite a difference so don't get greedy.

But doing the front down 1 is cheap because you only need the one sprocket and a slight chain adjustment. But if your chain is about 1/2 way through it's life then you are sacrificing the front sprocket because you'll have to change it with the next new chain anyway as Jim suggested. But at least it's a relatively cheap part.
 

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Discussion Starter #4
but putting more teeth in the back is sorta like "gearing down" right ? :p

can you guys give me a very rough estimate of how much this might cost?
a rear sprocket would be a ~$100 + $70 chain + another $100 for the front sprocket?

am close?

thanks

-d
 

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More teeth on the rear (or fewer on the front) is exactly gearing down. You increase your low end pull and decrease your top end speed..

A rough estimate on price:

New Chain (go Xring, rivoted master link): $95-$120
New Rear Sprocket: $50-$100
New Front Sprocket: $15-$40

Some one correct me if I'm worng, I haven't priced these out in a while.

Jim.
 

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is there any harm on the bike by changing the sprocket? ex: putting any additional stress on the engine?
 

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Discussion Starter #7
Big Jim said:
More teeth on the rear (or fewer on the front) is exactly gearing down. You increase your low end pull and decrease your top end speed..

A rough estimate on price:

New Chain (go Xring, rivoted master link): $95-$120
New Rear Sprocket: $50-$100
New Front Sprocket: $15-$40

Some one correct me if I'm worng, I haven't priced these out in a while.

Jim.

thanks, that's about what i expected.
-d
 

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is there any harm on the bike by changing the sprocket? ex: putting any additional stress on the engine?
No harm is done to the engine at all. Only difference is while you are cruising around your Rpm's will be a bit higher giving you the extra low end power. But our bikes were ment to rev high so its all good. Depending on the amount of teeth you go up in the rear your Rpm's should raise between 500 to 1000 higher. Not really a big deal at all.

Oh and for AlphaQ here is a link to one of my previous threads that may help you out a tad if you need it. And cost on the upgrade seeing that you have to replace the chain and both sprockets, will depend on weather you go with steel or aluminum. I got a quote from Bill at 5th Gear in white rock for about 250 bucks for a lighter weight 520 gold chain and hard anodized aluminum sprockets. That price is 20 bucks higher for me cause I want a gold chain though. Regular chain would make it 230. But if you go with aluminum sprockets, then make sure they are hard anodized aluminum rather than just plain aluminum. They are way stronger and are way lighter than steel. Bill said that after the full conversion I should loose about 8 to 10 pounds of weight from it. And that is off the drive train so it equals less horsepower loss and is more efficient.

Anyway hope i didn't confuse you with all that, here is the link...

http://www.bcsportbikes.com/forum/showthread.php?s=&threadid=140
 

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Gimmie whatcha got on gearing?

Changing sprockets is probably the cheapest modification when it comes to affecting performance. So what does going up/down teeth do? Well obviously something about top end speeds with trade-offs in accelleration? Someone quickly sum it up for me with pros/cons!

What about changing the chain to a lighter one?
 

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Check out AlphaQ's "new sprocket" thread below. It's all there.
 

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520 is a little lighter and some people say they can feel a difference in the spin up speed but I suspect what they're feeling is a hole in their wallet and the need to confirm that it was worth it. Admitedly it is better but I doubt anyone but a racer can feel it and then only with a stop watch.

One very important item. Stay away from aluminium rear sprockets. Someone over at SBN, YZFRob I think, had pics of a better name aluminium one with only a few thousand miles and it looked like a toothless old hag. Seems the anodizing holds up well for a while but when it lets go the base metal is about as hard as cheese on a warm day.

Here again aluminium is fine for racers looking for the last little bit but for street it's a bad selection from a mileage standpoint. But if you've done all the rest of the mods and you're looking for the last little bit then 520 and aluminium is the package to get but don't expect high mileage. Probably be lucky to get 8 or 9000 kms. 520 on steel sprockets wouldn't be TOO bad but there's less face area on the teeth so the sprockets will still wear a little faster than the 530 stuff.
 

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Discussion Starter #17
bah now im confused as hell
im asuming the size of the chain depends on the size of the sprocket?
what im looking here for, mostly, is not weight loss, or super mega performance. im looking for cheapness, quality and longevity. plus i want to be able to wheelie.
i mean kats weigh a whole lot. (450lbs). I doubt +-1 pound would be a big deal.
thanks
-d
 

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AlphaQ said:
bah now im confused as hell
im asuming the size of the chain depends on the size of the sprocket?
what im looking here for, mostly, is not weight loss, or super mega performance. im looking for cheapness, quality and longevity. plus i want to be able to wheelie.
i mean kats weigh a whole lot. (450lbs). I doubt +-1 pound would be a big deal.
thanks
-d
Then stay with the stock chain size (that 520 or 530 or whatever your's is) but get a REAR sprocket 2 or 3 teeth BIGGER. This means a new chain but it sounds like you're replacing the whole lot thanks to wear anyway. Right?

If you're just wanting to try it out then cheaply then get a FRONT sprocket only that is one tooth SMALLER. Put it on with the existing chain and rear sprocket and just adjust the tensioner.

Assuming you have roughly a 1:3 front/rear tooth count ratio like most then the one tooth down in the front is the same as 3 up in the back.

Your cruise rpms will be a little higher for any given speed but the acceleration will be better and it *should* give you a bit more for wheelies. Don't expect 2 gear midrange rollon wheelies though. It's just no going to happen with a Kat. Even first gear ones will still need a couple of tricks probably. Like a quick off-on to bounce the front and stuff like that.

It's not a liter bike after all :flip
 

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absolutdm said:
As a general rule, about how long do most chains last? How do you know when it's done?
Well cared for chains can last for 50 to 60,000 Kms. Badly care for as little as 10,000. But realistically our sportbike chains and sprockets being ever so lightly used by us :rolleyes are doing well if we get 30,000 to 40,000 kms.

Tight links from internal rust is something to watch for when you're cleaning and lubing. A sure sign of a new chain in your immediate future.

Any amount of visible hooking of the sprocket teeth is a sure sign the whole system needs replacing. And I mean ANY visible sign. But that doesn't mean you can't go away for another weekend or run it just fine until the next paycheck if it's just barely noticable. It's just that the system will consume a bit more power than a brand new one. And just because you see the first signs of hooking the sprocket isn't going to go bang in the night or anything. When it gets to this point you'll often hear more of a buzzing than a good system. But it sneaks up on ya slowly so you may not notice it but the next time you go riding with someone they may tell you that you're bike's chain sounds buzzy compared to their's.

And if/when you notice a tiny bit of rear sprocket hooking pull the little front sprocket cover. Chances are what you see will scare ya. The front wears a lot quicker than the rear.
 
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