Hawk 250 - Is It Ok To Just Change Rear Sprocket?

[HawkTwoFifty]

So I would like to do the 17/45 sprocket changes that everyone recommends to gain some top-end speed on the highway on my Hawk 250. But I am nervous about going bigger on the front sprocket in the event of a chain failure resulting in a damaged case. Probably a one-in-a-million-rare chance but I dont want to chance it.

So I was informed that I can go with a 40-tooth rear sprocket and leave the stock front sprocket in place for the same gearing result as 17/45. Does this sound accurate? And will there be any disadvantage to changing just the rear sprocket to a 40-tooth? Just wondering if there are any disadvantages since people usually change both sprockets for this change, thanks.

[JerryHawk250]

40 tooth rear will be very close to the 17/45 combo with 15/40 being slightly lower. That's what I run when I go strictly off road. You can always change the front to a 16 or 17 later on if you plan on just street riding. Here is a link to a sprocket calculator. just type in Hawk in the filter and then select Hawk 250. http://woodsware.aciwebs.com/gears/ You can play around with that to figure out what you want to do. I'm currently running 16/40 because I have been doing about 50/50 on and off road cruising 55-60 mph on the highway.

[HawkTwoFifty]

40 tooth rear will be very close to the 17/45 combo with 15/40 being slightly lower. That's what I run when I go strictly off road. You can always change the front to a 16 or 17 later on if you plan on just street riding. Here is a link to a sprocket calculator. just type in Hawk in the filter and then select Hawk 250. http://woodsware.aciwebs.com/gears/ You can play around with that to figure out what you want to do. I'm currently running 16/40 because I have been doing about 50/50 on and off road cruising 55-60 mph on the highway.

Thanks a lot JerryHawk250. If I run a 40-tooth rear sprocket with a stock front sprocket, how do I determine how many links my chain should have? Because I also plan on buying a high quality chain for my Hawk 250 and wondering how many link chain I should order for a stock front + 40-tooth rear sprocket setup. Thanks!!

[JerryHawk250]

Thanks a lot JerryHawk250. If I run a 40-tooth rear sprocket with a stock front sprocket, how do I determine how many links my chain should have? Because I also plan on buying a high quality chain for my Hawk 250 and wondering how many link chain I should order for a stock front + 40-tooth rear sprocket setup. Thanks!!
I'm still running the stock chain and only removed 2 links which makes it 128 links. 128 works with 15,16 and 17 front with the 40 rear.

[HawkTwoFifty]

I'm still running the stock chain and only removed 2 links which makes it 128 links. 128 works with 15,16 and 17 front with the 40 rear.

Great! Thanks so much for your help!!

[JerryHawk250]

Only reason you would need to change both sprockets and chain is if your current sprockets are showing some wear.

[JeremyC]

I find this website to be handy: http://www.sprocketcalculator.com/