17/40 sprocket setup for hawk 250

Zapkin · 08-27-2024, 08:54 AM

Well, since it has become abundantly clear that I won't be taking the Hawk off road anymore, I am interested in getting the RPM's as low as possible for street riding. I've seen several people on Amazon switch to the 17/40 setup. I understand I will lose some oomph. But my question is, will my 128 tooth chain fit? I've seen on Amazon that the 17/40 and 128 tooth chains are often bought together, but I wanted to ask you guys before ordering. Thanks.

**JerryHawk250** · 08-27-2024, 10:36 AM

A 128 link chain will work.

Bill Hilly · 08-27-2024, 11:41 AM

In my opinion , a 40/17 is not going to be a very good combination for you , nor for most people. I know you changed rear tire, and it reduced your gearing a little, but a 42-43/17 is really about as high as you should go. Some people that use the 40/17 have bikes like the TBR7, which has a smaller rear wheel, but on a Hawk, with an internally stock motor, and a hefty rider, living in a hilly part of the country, it's just going to make it hard to take off, and especially hard to take off from an upward slope. I think it would be harder on the bike than the few extra rpm that you want to reduce. I see post on the Facebook groups were people are recommending " crazy" combinations like 34/17. Jerry ran sprockets that ,if I remember right were 40/17, and was one of the few that was able to benefit from them, but he had a hotter motor, is under 200lbs, and lives in Louisiana.

ProDigit · 08-27-2024, 12:02 PM

Quote:

Originally Posted by Bill Hilly

In my opinion , a 40/17 is not going to be a very good combination for you , nor for most people. I know you changed rear tire, and it reduced your gearing a little, but a 42-43/17 is really about as high as you should go. Some people that use the 40/17 have bikes like the TBR7, which has a smaller rear wheel, but on a Hawk, with an internally stock motor, and a hefty rider, living in a hilly part of the country, it's just going to make it hard to take off, and especially hard to take off from an upward slope. I think it would be harder on the bike than the few extra rpm that you want to reduce. I see post on the Facebook groups were people are recommending " crazy" combinations like 34/17. Jerry ran sprockets that ,if I remember right were 40/17, and was one of the few that was able to benefit from them, but he had a hotter motor, is under 200lbs, and lives in Louisiana.

What rpm range you're getting at what speed?
You should be aiming towards 1k rpm every 10 mph, or 5k rpm at 50mph.
On my Xpect I run a 17/36t as ideal lowest gear. Been asking if the hawk has the same gear ratio as the Xpect, or not, and if it does, you should go with a 36-38t rather than a 40+t.

**JerryHawk250** · 08-27-2024, 12:28 PM

Quote:

Originally Posted by ProDigit

What rpm range you're getting at what speed?
You should be aiming towards 1k rpm every 10 mph, or 5k rpm at 50mph.
On my Xpect I run a 17/36t as ideal lowest gear. Been asking if the hawk has the same gear ratio as the Xpect, or not, and if it does, you should go with a 36-38t rather than a 40+t.

The Xpect has a smaller diameter rear tire than the hawk. The 40 tooth on the Hawk will be close to the 37-38 tooth on the xpect.

Dusman · 08-27-2024, 01:55 PM

I ran a 17/40 sprocket set-up on the Hawk for about 4 years after porting and polishing the head of my CG250 engine and loved it. I could comfortably run 65-70 mph all day long on my local highways without overstressing the engine. If you're running primarily on the street and doing occasional light off roading (i.e., double track dirt or gravel roads, riding across fields, etc.), then 17/40 is excellent.

Zapkin · 08-27-2024, 12:17 PM

Quote:

Originally Posted by Bill Hilly

In my opinion , a 40/17 is not going to be a very good combination for you , nor for most people. I know you changed rear tire, and it reduced your gearing a little, but a 42-43/17 is really about as high as you should go. Some people that use the 40/17 have bikes like the TBR7, which has a smaller rear wheel, but on a Hawk, with an internally stock motor, and a hefty rider, living in a hilly part of the country, it's just going to make it hard to take off, and especially hard to take off from an upward slope. I think it would be harder on the bike than the few extra rpm that you want to reduce. I see post on the Facebook groups were people are recommending " crazy" combinations like 34/17. Jerry ran sprockets that ,if I remember right were 40/17, and was one of the few that was able to benefit from them, but he had a hotter motor, is under 200lbs, and lives in Louisiana.

thanks Bill, perhaps I will try the 42 but I have pretty much lost my desire to do any exploring and just want easy to ride around town now. I have the 17/44 on it now and its buzzing pretty freakin hard at 55-60. Annoying. It was not as pronounced before I put the new tires on. next weekend my friend and I are going to give it a good looking over. I can do most of it myself, but he is younger, stronger and has more mechanical skill than my elderly, atrophied brain. hehehe (i might be exaggerating on that part)

**JerryHawk250** · 08-27-2024, 12:24 PM

With the 40 tooth rear sprocket, you can always drop down to 16 or 15 tooth front if you find it to tall of a gearing. I use to swap the front sprocket when going from street to off road. Easy to swap back and forth.

Do©Hawk · 08-27-2024, 02:54 PM

Quote:

Originally Posted by Zapkin

Well, since it has become abundantly clear that I won't be taking the Hawk off road anymore

Did something happen?

Zapkin · 08-27-2024, 07:38 PM

Quote:

Originally Posted by Do©Hawk

Did something happen?

having about 1 out of 3 days when my equilibrium is up to it. I went back on the trails with my son in law a while back and nearly dropped the bike several times due to my balance being off and I am just overall weaker this year. Been to the doctors but nothing is resolved.

Do©Hawk · 08-27-2024, 09:31 PM

Quote:

Originally Posted by Zapkin

having about 1 out of 3 days when my equilibrium is up to it. I went back on the trails with my son in law a while back and nearly dropped the bike several times due to my balance being off and I am just overall weaker this year. Been to the doctors but nothing is resolved.

That's a bummer. I feel for you. My wife has a lot of balance and mobility issues. It limits what she and we are able to do. Her issues have been long running and unresolved. I have little faith in the healthcare machine due to struggles my wife has had.

Zapkin · 08-28-2024, 06:43 AM

Quote:

That's a bummer. I feel for you. My wife has a lot of balance and mobility issues. It limits what she and we are able to do. Her issues have been long running and unresolved. I have little faith in the healthcare machine due to struggles my wife has had.

It's my fault. I've treated my body like an amusement park since I discovered alcohol and recreational drugs, and now I suffer the consequences. I have some plans to mitigate the damage, but we'll see what happens.

Zapkin · 09-10-2024, 02:11 PM

Okay, so I installed the 42-tooth sprocket and those fancy green-hued sprocket studs from Amazon.

So far, I like it. It definitely makes riding at 55 less dramatic. Later, I will hit the backroads and see how badly it affects my ability to get up hills. I don’t really mind because 90% of my riding these days is back and forth to Wheeling on Route 2, where I do 55 the whole way, or around Moundsville. It also felt good to take off the wheel, inspect everything, and just give it a good once-over.

Zapkin · 09-12-2024, 02:51 PM

I wish we could change the thread title to 17/42 setup. Anyway, I rode a nice ride today, it's hard for me to believe that two teeth can make as much difference in overall riding experience. And it can still get my big booty going just fine. If you don't ride offroad much and you want a smoother experience, try it. worse case Ontario you can take it off.

Deckard_Cain · 10-03-2024, 10:38 AM

Quote:

Originally Posted by Zapkin

I wish we could change the thread title to 17/42 setup. Anyway, I rode a nice ride today, it's hard for me to believe that two teeth can make as much difference in overall riding experience. And it can still get my big booty going just fine. If you don't ride offroad much and you want a smoother experience, try it. worse case Ontario you can take it off.

17/42 sounds like a good combo. I run 16/40, which is about the same as a 17/43 ish. I also have a fully worked over engine, which, without the extra power, I think it would be too much of a good thing.

I geared it to be usable on road, able to cruise the 55mph river road to work and back, and up north and around Northern MI without buzzing at a million rpm. I'm roughly 5500rpm at 55mph with power and gearing enough in 5th gear to just pull up to 70 if needed (never needed yet).

If I need more low end, I just drop the 15t front back on, or if the opposite, I can plop on a 17t front and readjust chain tension.

good call on the 17/42.

08-27-2024, 08:54 AM	#1
Zapkin Join Date: Sep 2022 Location: Ohio Valley Posts: 745	17/40 sprocket setup for hawk 250 Well, since it has become abundantly clear that I won't be taking the Hawk off road anymore, I am interested in getting the RPM's as low as possible for street riding. I've seen several people on Amazon switch to the 17/40 setup. I understand I will lose some oomph. But my question is, will my 128 tooth chain fit? I've seen on Amazon that the 17/40 and 128 tooth chains are often bought together, but I wanted to ask you guys before ordering. Thanks. __________________ 2022 Hawk 250
	2

08-27-2024, 10:36 AM	#2
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,723	A 128 link chain will work. __________________ 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

08-27-2024, 12:24 PM	#8
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,723	With the 40 tooth rear sprocket, you can always drop down to 16 or 15 tooth front if you find it to tall of a gearing. I use to swap the front sprocket when going from street to off road. Easy to swap back and forth. __________________ 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

09-10-2024, 02:11 PM	#13
Zapkin Join Date: Sep 2022 Location: Ohio Valley Posts: 745	42 tooth and new studs Okay, so I installed the 42-tooth sprocket and those fancy green-hued sprocket studs from Amazon. So far, I like it. It definitely makes riding at 55 less dramatic. Later, I will hit the backroads and see how badly it affects my ability to get up hills. I don’t really mind because 90% of my riding these days is back and forth to Wheeling on Route 2, where I do 55 the whole way, or around Moundsville. It also felt good to take off the wheel, inspect everything, and just give it a good once-over. __________________ 2022 Hawk 250
	3

09-12-2024, 02:51 PM	#14
Zapkin Join Date: Sep 2022 Location: Ohio Valley Posts: 745	I wish we could change the thread title to 17/42 setup. Anyway, I rode a nice ride today, it's hard for me to believe that two teeth can make as much difference in overall riding experience. And it can still get my big booty going just fine. If you don't ride offroad much and you want a smoother experience, try it. worse case Ontario you can take it off. __________________ 2022 Hawk 250
	0

08-27-2024, 11:41 AM	#3
Bill Hilly Join Date: Feb 2021 Posts: 1,003	In my opinion , a 40/17 is not going to be a very good combination for you , nor for most people. I know you changed rear tire, and it reduced your gearing a little, but a 42-43/17 is really about as high as you should go. Some people that use the 40/17 have bikes like the TBR7, which has a smaller rear wheel, but on a Hawk, with an internally stock motor, and a hefty rider, living in a hilly part of the country, it's just going to make it hard to take off, and especially hard to take off from an upward slope. I think it would be harder on the bike than the few extra rpm that you want to reduce. I see post on the Facebook groups were people are recommending " crazy" combinations like 34/17. Jerry ran sprockets that ,if I remember right were 40/17, and was one of the few that was able to benefit from them, but he had a hotter motor, is under 200lbs, and lives in Louisiana.
	1

08-27-2024, 01:55 PM	#6
Dusman Join Date: Jan 2018 Location: NC Posts: 237	I ran a 17/40 sprocket set-up on the Hawk for about 4 years after porting and polishing the head of my CG250 engine and loved it. I could comfortably run 65-70 mph all day long on my local highways without overstressing the engine. If you're running primarily on the street and doing occasional light off roading (i.e., double track dirt or gravel roads, riding across fields, etc.), then 17/40 is excellent.
	1