cyberpoet and friend help me! sprocket problems

[Bulletproof Enemy]

ok... CP whats up... i know i need to come to you for some help... let me explain whats going on


initialy when i purchased my kat new in 99, it was stock.... it would of never ever reached the end of the spedo (150 is it?) plus on the last gear(6) it was a dog getting any speeds....

i added a full hindle system, K&N, jetted, dyno tuned, and the power now screamed accross the RPM range, and power started much much earlier, plus it let it bounce of the rev limiter at top end now... so my kat will have enough guts to let it rev out and hit redline in 6th gear and pretty quick at that....

SO

i bought a RK 520 chain conversion kit from another memeber on here just a week ago or so..installed that and... UGH! (kit was perfect condition BTW thanks!!!! ) and what i mean... by all this, is my bike rips through the gears so fast.. when i am in 6th gear, just crusing at 90mph or so, im at 8k in my RPMS in 6th gear... my bike feels like i am riding in my PREVIOUS 5th gear from the other sprocket setup... i almost cant even some of you put this on your bike!!!! basically it feels like my other setup with extremly tight gears, meaning i just run right through every gear, then im in 6 with no more to go...

currently installed is the vortex -1/+2 combo


what should I do here? i now have a brand new chain, and the other stuff... plus install labor charge, and i did get my stock parts back... i am seriously wanting my top speed (and the fuel economy sucks...) my shop said i could just get a 14 front end it would restore it back so its good now.. what do you think? my bike with its hindle setup is so much more aggressive then stock its not funny... im not sure now why guys would want to do this UNLESS you were doing 1/4 miles or something... i can pull my front end up a bit easier, but at the loss of my top end speed.. and fuel economy I dont think so... as stated before i cant believe people put this on the bike as a good setup

I was thinking maybe on a stock bike, where the bike might have enough balls to hit the top end, thats why this setup would work, because now it would reach THAT top end... but my bike seriously has a lot more power than a stock kat and will easily bounce the needle to 150mph, its the engine rev limit that kicks in, not running out of juice...

if i went with an elongated first gear, i could hit a higher top end right? but the rev limit cant be changed... basically i want to "save" most of my new parts and only by 1 sprocket...


CP and friends please help!

[Mojoe]

it is just my opinion, but I think you are shooting too high with wanting to hit 150mph. You will have to go in the other direction with the sprockets....and to do it enough to hit 150, you will be sacrificing ALOT of the low-end torque.
I might be wrong cuz I have no experience with the smaller kats....but from what I have read in other posts, it is the conclusion I have come to.

[Bulletproof Enemy]

my kat with the stock gearing would finish the speedo off.... i was hoping of loosing MAYBE 10mph max... now i know the speedo's are not all that accurate after 100mph, but i assure you the bike would hit its 150mph mark indicated easily... meaning its really doing what, 135ish?140 MAYBE...

[Mojoe]

my kat with the stock gearing would finish the speedo off.... i was hoping of loosing MAYBE 10mph max... now i know the speedo's are not all that accurate after 100mph, but i assure you the bike would hit its 150mph mark indicated easily... meaning its really doing what, 135ish?140 MAYBE...

ya...maybe 135ish. Cyber posted something about the max speed being something like that in a recent post.

[BeekMan]

I've got +2 (49) Vortex in the rear with no modded front (14) and I don't have a problem with my revs at highway speed or a major fuel economy issue. I'm happy with my balance. Spedee has +3 rear and -1 front and he's not complaining either. We both have 530 chains and I've never thought about it but I don't think that would make a difference in the gear ratios...maybe a bit less unsprung weight to contribute to the low end pull. I guess you'll have to decide which you want more. If you want to go back a bit I'd get a 14 front sprocket.

[Spedee]

As Beekman said: No complaints here. Our engines love to rev!

[letsride]

why did you go with a 520 chain .

[The CyberPoet]

(A) A Kat 600, even with a jetkit, aftermarket exhaust, etc., will never hit 150 in the real world. Period. Given the stock compression ratios (11.5:1 on the 98+ Kat 600), the bike's engine simply can not make enough power at top RPM to overcome that much wind resistance. A stock bike should be able to do 130-135, and a jetted/mod'd bike should be 134 - 139 max (tucked down). If you see a significantly higher speed than this, either you are tiny-tiny (say 4'9" and 100lbs wet) or far more likely, you never had your speedo recalibrated (or corrected with a yellowbox or speedo healer) after changing gear ratios/tires/etc. Remember that the 98+ speedo calculates the speed based on the rotations of the output shaft of the transmission and assumes that your gears are a specific ratio (3.1333 drive ratio, based on the stock 98+ Kat's OEM 15/47 sprocket teething) and that the back tire is a specific size (Macadam 90x) during this calculation. Change the parameters and the speedo results will be off your real speed by that much...

(B) If you were happy with the performance of your old gearing, I would recommend going back to it, especially if your primary concern is top-end speed. Those who modify their gearing do so specifically to get more off-the-line acceleration and put their average speeds into the power-band better; they are not usually the type who spend much time at peak speeds (or they wouldn't have been likely to mod the gears that heavily). You didn't say what the gearing now is -- just that you stepped down to a 520 and went -1/+2 (but was it at 15/47 before, or was it already modified previously to something like 14/45, etc?).

(C) I've never been thrilled about the concept of slapping a 520 conversion kit on, for a variety of reasons. IMHO, I don't feel the weight savings is significant enough to justify it on a 500lb/70HP bike. Unless you selected the chain with the help of a manufacturer's recommendation, you probably got the wrong chain for your intended use (not all chains are the same even in the same size; for example a "racing chain" is designed to be replaced after a race or two, while the OEM chain is designed to give you at least 12k miles of life with proper maint). Most chain manufacturers actually make 3 to 8 different chains of any one type, aside from differences in length/link-count.

Good Luck!
=-= The CyberPoet