Bashan 250 Sprocket Question

[RVArider]

I recently purchased a used Bashan 250. It has stock 17/46 sprockets. From what I've read, this seems like a good combo for mostly street riding but will also be sufficient for some trail riding. The problem I'm having is first and second are very short. Going through an intersection I have to shift into second 15 ft off the line, which is kind of annoying. It also sucks when riding two up and I have to constantly shift when driving around the city.

Any recommendations for lengthening the gears a bit? My knowledge of sprocket ratios is pretty limited.

[Nyccooldude]

I to would like to know what would be best? It does have short gears but I'm also looking to reach higher speeds 70mph if possible. I know I have to get a new exhaust and reject the carb

[Cravin01]

Well there are a lot of different scenarios in which to choose your ratio.

Your stock setup is 17/46 with a basic top end at 64.2 running 7000 rpm at 60mph. a 2.706 ratio

now which way to go? more top end or more gut for off roading and which sprocket to change.

keeping the front sprocket at 17=

17/43 68.7 top end running 6540 rpm at 60mph. a 2.529 ratio
17/42 70.4 top end running 6390 rpm at 60mph. a 2.471 ratio
17/41 72 top end running 6244 rpm at 60mph. a 2.412 ratio
17/40 74 top end running 6092 rpm at 60mph. a 2.353 ratio

A 16 or 15 tooth front sprocket would make it a higher rever with a slower top end, something I'm not interested in.

there are plenty more combination to list but I hope this gets you in the right direction.


here is the link thanks to MegaDan!

http://woodsware.aciwebs.com/gears/

put in 2016 and press filter and then OK,
Choose 2016 Bashan Brozz 250 in the bike scroll down area.
(same tire size and motor)

Or choose 2016 Haosen Hawk 250 in the bike scroll down area to look up Hawk combinations!

[goat67]

I added the 2016 Bashan Brozz to the web site. I have found the calculations it provides to be be pretty accurate.

Another thing to take in to consideration is the tire it plays a small role also, a taller tire will increase the speed a bit.

[Cravin01]

Originally Posted by goat67

I added the 2016 Bashan Brozz to the web site. I have found the calculations it provides to be be pretty accurate.

Another thing to take in to consideration is the tire it plays a small role also, a taller tire will increase the speed a bit.

Then I would like to thank you, I'm going try a few combinations off your chart.

What sprocket cominations have you tried and what did you end up with? I'm thinking of starting with a 17/42.

[goat67]

Originally Posted by Cravin01

Then I would like to thank you, I'm going try a few combinations off your chart.

What sprocket cominations have you tried and what did you end up with? I'm thinking of starting with a 17/42.

Hello
All I had to do was enter the info from the owners manual, the program did the rest.

I have not changed anything yet as far as gearing it. I may change to a 520 chain and when I do that I will tinker a bit I will be going for higher top end.
I do not think it will handle to much higher gearing for me that is.

I am 6'1 and 200 lbs so that needs to be taken into consideration also.

Let us know how the 42 gear turns out.

[Cravin01]

With increased power of the aftermarket exhaust I'm hoping it will pull just fine, I also have a pumper carb on the way and hope it will help throttle response and there is a port job in the future so fingers crossed.

I'm no lightweight myself at over 220 but the bike pulls great right now.