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First off i have tried to get the Renthal 368-5250-13GP with no luck from ATV shops and Dealerships, cycle gear alike.

SO MY QUESTION IS IF YOU HAVE IT AND ORDER IT WHAT IS THE EXACT PLACE WITH CONTACT INFO?

I have received a Sunstar sprocket with some crazy as spline design from the 80's era. I may even slip you $2.00 paypal for your info!

Thank you lord watch over my friends, family and my dog TURBO!

AMEN
 

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Discussion Starter #6
That is where i got the number just typed it wrong here, i hi-jacked your photo from your thread a few weeks ago when i started my search. So since i have your attention where did you order it from?
 

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... So since i have your attention where did you order it from?
Aufitt is in Australia... shipping would be a small fortune to the U.S. I'm pretty sure you can find this sprocket in the states. If you don't find the Renthal sprocket, the JT Sprockets (P/N JTF1321-13) is just as good, for half the price of the Renthal. Search for it using 1996 - 2005 Honda XR250R as the model application... searching using CBR250R won't get you anywhere.
 

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You want to raise the ratio of an already under-geared bike? :D (don't hurt me)
 

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What will this do?



Sent from my Desire HD using Motorcycle.com Free App
 

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Make your bike lose its top end speed...........
Er... no, ever redline in 6th often?

If that was the case my highest speed at one track would be back struggling to get 130kph instead of the 142.2 it is now.
bet if I went lower again it would be near 150.

the gps does not lie.
 

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Discussion Starter #15
You want to raise the ratio of an already under-geared bike? :D (don't hurt me)

Yes i do! not worried about a few mph, rather have a lil more torque in my lower gears as it suits my drive to work and play time.:)

Make your bike lose its top end speed...........
Wait the salesman didnt tell me there is a "top end speed" option,when i bought my bike!

But all in all people usually dont understand how much gears change the overall characteristic of a anything. Untill the them selves have spent time before and after the modifications.

So we should stop here, so nobody starts getting all engineer on us. My calculators say this and that, b.s. is for the birds. Although i would like to thank all the engineers in the automotive industry as a technican fixing there ******************** now for 16yrs, i have made a hell of a nice living and built a really nice IRA:D:D:D!

Thanks for the info on where to get them, i was going to pay the extra for the Renthal but i like $ on the JT!
 

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Ok, so it gives you more torque in the lower gears? and a little less of a top speed?

I'd be happy with that since I don't really need to go faster than 80mph (and that's still breaking the limit) on my daily commute...but I do like to have that extra pull from the lights so I can get away from the traffic.

Any other pros and cons? Gas mileage change?
 

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It cascades the lower gearing across all gears. Changing final drive (sprocket) ratios will bias the the bike towards acceleration or top theoretical speed per gear. The fuel economy change is marginal if anything. I've done 3 different ratios on the bike and got 68mpg no matter what.
 

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Ok, so it gives you more torque in the lower gears? and a little less of a top speed?

I'd be happy with that since I don't really need to go faster than 80mph (and that's still breaking the limit) on my daily commute...but I do like to have that extra pull from the lights so I can get away from the traffic.

Any other pros and cons? Gas mileage change?
To add to what Rusty says above, I've found that I can use the next higher gear for a given road speed with the 13T front sprocket, while running at an RPM that is closer to the meat of the power band.

For example:
Gear _______ Road Speed (MPH) ______ 14T RPM _______ 13T RPM
6 ....................... 70 ........................... 7000 ................ 8000

6 ....................... 60 ........................... 6000 ................ 7000

6 ....................... 50 ........................... 5000 ................ 6000

5 ....................... 40 ........................... 4500 ................ 5200

Overall the engine runs better at these higher RPM's, and responds much better to further throttle input. The whole bike just seems more efficient... I haven't noticed any significant change in fuel consumption with the 13T sprocket.
 

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'raising' ratios may take some edge off acceleration, plus lower rpm
in 6th gear, thus better mpg and easier on engine = longer life..
this may be 'good' for novice riders, and for the motorcycle..
you of course might wish to retain the edge on acceleration
plus bring 6th gear closer to 5th, away from 'overdrive'..

effectively, lowering countershaft teeth can increase, speed,
in the real world incl, on the flat, uphill, two-up, no long runups..

its not hard to imagine honda designing in ratios to include
considerations for novice riders and fuel economy/engine life..
esp for this motorcycle oriented to include novice riders..

lowering, countershaft sprocket teeth adds loading on chain and teeth,,
compared to changing ratio by adding teeth to driven sprocket..
also, apparently, odd teeth numbers are better than even numbers...
 

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The bikes come stock with a general purpose gearing that would be usable to all people without modification. Changing the gearing to bias it towards how you want to use the bike's finite supply of horsepower is personal preference. Some want better highway fuel economy and a calmer ride; some want more acceleration and low speed control. Either way, the pro/con arguments on the physical effects on the bike are splitting hairs, honestly. That and sprockets are very very cheap compared to regearing say, a car.
 
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