Hawk 250 gearing. Want more top end but good low end

Camdg2010 · 04-13-2021, 02:38 PM

Looking for advise on changing gearing. I already did the 17/45 or whatever ot was (can't remember) it does decent at about 64. Ide like to squeeze a little more top end speed out but still have decent low end torque. What gearing should I do? Can I keep the 17 front and drop the rear a size?

**JerryHawk250** · 04-13-2021, 02:52 PM

I was running a 17/40 combo on my hawk. Good for the street but will kill low end for off road. Maybe a 42 or 43 rear.

Newt232 · 04-15-2021, 07:49 PM

I just pulled off the cover on mine and discovered I'm running a 17/54 and top out at 100 kph at 9500 rpm or so. I'm thinking I want to drop down to a 42 in the back. The BCD is 90mm x 4 for the rear sprocket, and it's .3" thick. I'm guessing the chain is 428, but am not 100% sure.
Would something like this work?
https://www.ebay.com/itm/JT-Sprocket...QAAOSw53dgF50-

Camdg2010 · 04-17-2021, 05:24 PM

Quote:

Originally Posted by Newt232

I just pulled off the cover on mine and discovered I'm running a 17/54 and top out at 100 kph at 9500 rpm or so. I'm thinking I want to drop down to a 42 in the back. The BCD is 90mm x 4 for the rear sprocket, and it's .3" thick. I'm guessing the chain is 428, but am not 100% sure.
Would something like this work?
https://www.ebay.com/itm/JT-Sprocket...QAAOSw53dgF50-

im using a 428 chain now. im getting about 64 on average.

XLsior · 04-17-2021, 07:40 PM

using this chart I went with 16f 45r as my first ratio test.

I personally didn't want to commit to 17t front as I don't plan on doing much highway distance and where I live is steep hills and twisties. So I went mid range.

hindsight, 44rear might be easier to come by but the seller had a 45 at the time and offered it...

They say 3 teeth in the rear sprocket = a 1 tooth change in the front or so. Also smaller sprockets wear out faster than larger sprockets and are harder on the chain, but larger sprockets result in a longer chain therefore larger reciprocating mass and friction loss... so something to consider.

my Xl185 runs a 21f 18r wheel.

Boatguy · 04-15-2021, 09:15 PM

Need 6th gear on these bikes. Badly

Camdg2010 · 04-17-2021, 05:23 PM

Quote:

Originally Posted by Boatguy

Need 6th gear on these bikes. Badly

yes these do!

04-13-2021, 02:38 PM	#1
Camdg2010 Join Date: Oct 2020 Posts: 29	Hawk 250 gearing. Want more top end but good low end Looking for advise on changing gearing. I already did the 17/45 or whatever ot was (can't remember) it does decent at about 64. Ide like to squeeze a little more top end speed out but still have decent low end torque. What gearing should I do? Can I keep the 17 front and drop the rear a size?
	0

04-13-2021, 02:52 PM	#2
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,657	I was running a 17/40 combo on my hawk. Good for the street but will kill low end for off road. Maybe a 42 or 43 rear. __________________ 2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
	1

04-15-2021, 09:15 PM	#6
Boatguy Join Date: Feb 2021 Location: Northeast Posts: 934	Need 6th gear on these bikes. Badly __________________ 2020 Lifan x-pect
	3

04-15-2021, 07:49 PM	#3
Newt232 Join Date: Oct 2018 Posts: 25	I just pulled off the cover on mine and discovered I'm running a 17/54 and top out at 100 kph at 9500 rpm or so. I'm thinking I want to drop down to a 42 in the back. The BCD is 90mm x 4 for the rear sprocket, and it's .3" thick. I'm guessing the chain is 428, but am not 100% sure. Would something like this work? https://www.ebay.com/itm/JT-Sprocket...QAAOSw53dgF50-
	0