Hawk transmission gear ratios

[kirkallen143]

Searched on here, but got a bunch of different ratios. Any one know the primary reduction, 1st thru 5th, and final for the Hawk 250 engine? Wanted to know what rpms I am running with different sprocket combinations at given speeds. Thanks.

Kirk

[AresROC]

Probably best to open up and count the gears... you never know.

In the meantime, here is another set of data from Bashan BSR :hehe:
Factory sprockets 17 front, 46 rear (No I didn't count them, yet)


Sure would love to find out where my "Betraying" light is...:D

[JerryHawk250]

I entered all the Hawk information in this calculator. Just type Hawk into filter then pick the 2016 Haosen Hawk 250. http://woodsware.aciwebs.com/gears/

[kirkallen143]

Jerry, you just made my day! Now folks can see what rpms they are running with different gear and rear tire setups. Might have to sticky this up to the top of the DS forum.

Really appreciate what you have done...

Kirk

[JerryHawk250]

Jerry, you just made my day! Now folks can see what rpms they are running with different gear and rear tire setups. Might have to sticky this up to the top of the DS forum.

Really appreciate what you have done...

Kirk
Glad to help.
I had Megadan put in his Sticky in the DS section.

[kirkallen143]

Great! Yeah now it will be pretty neat to know what the engine sounds/feels like at certain rpms while riding.

Kirk

[Noobie101]

I put in the gearing i would like to run..
Could anyone chime in on this setup?.
Tbh i have a 20-25 mile comute to work and
would like to stay in my 6k-7k rpm range..
I do plan on doen the better carb and pod filter
and remove the oem air box to accomidate
Better storage space

[JerryHawk250]

What speeds will you be looking at?

[Noobie101]

Hwy speed is 70 posted and everyone
Stays around 75ish if not a little more

[JerryHawk250]

Hwy speed is 70 posted and everyone
Stays around 75ish if not a little more

16/39 should be good. I'm running a 17/40 and can hit 75 with ease but I also ported and decked the head. On stock engine with a few mods 70 mph is doable but will be almost wide open throttle.

[Noobie101]

I wouldnt have the funds or the know how to do the pnp but i do plan on getting the hawk head so idk maybe

[Noobie101]

There was another head that was interchangeable but ibcant find it atm plus at wotk its hard to look for long

[Noobie101]

Do you think there would be much issuses getting it to 80 if i wanted being im doen almost every mod on here exept the pnp

[JerryHawk250]

I've only hit 80mph (GPS) once and was enough for me. Never tried a top speed since. These bikes aren't designed for that kind of speed and the CG engine aren't designed for high rpms. I found anything over 70 mph and my bike starts to get squirrely because I'm running stock nobbies on it. Maybe with street tires it would feel more stable. If you're looking for something to 75-80 then something that has 25hp or more. Even something like the KPR200 can top out about 80mph.

[OneLeggedRider]

A 2.6 ratio is the sweet spot for these bikes and you'll never see more than 70mph unless you pnp the head and put a bigger carb on it. If you weigh less than 150lbs 2.5 will be your sweet spot. Just divide the number of teeth on the rear sprocket by the number of teeth on the front sprocket. :tup:

[Noobie101]

I only have a maybe 5-8 mile stretch of hwy 70mph posted
The rest would be 60/65 posted

[franque]

I'd get something bigger if the goal is running 70 at a distance, especially if it gets windy. With the higher height of a Hawk, I'd want a bigger bike for more stability, and at least a more powerful motor. It could work, but it's pushing the design envelope. I would look at something with at least a 300cc motor.

[Megadan]

I have held 70mph on my old bike for a few miles (Full bolt on mods, no head porting and a mikuni clone with 17/43 sprockets). It is possible, but as previously mentioned, it will be pretty much wide open the whole time. I could hold 60-65mph almost all day on flat ground without the throttle being pegged though, at least as long as I wasn't fighting a strong head wind. Realistically speaking, that is about the practical limit of these little motors.

Head porting, bigger carbs, even cams, can extend those limits a little bit, but it's only a little bit. The real perk of doing that kind of work is to gain back some of the lost acceleration by running those higher ratios, or stretch out the useable rpm range of the motor with an existing ratio (cam). If you took a Hawk with basic bolt ons and my bike, put the same sprockets on them, and had me ride both and recorded their performance, my bike would definitely perform better in most aspects, but their top speeds wouldn't be that dissimilar, with maybe 4 or 5mph more at the very top end of things.

If you need to hold speeds like that on the regular then you will really want to look into a bike with more power, or better aerodynamics. Dual Sports aren't meant for speed, they are like riding a 2 wheeled parachute.

[Emerikol]

I have done some of the simple things to my Hawk (rejetted the stock carb, pod air filter, and aftermarket exhaust) and I struggle to do anything over about 67mph. I had one time back in Georgia where I hit nearly 72, but then I got a serious case of the death wobbles and almost came off the bike in a spectacular conflagration. That was on the stock knobbies. I'm running a 17/39 setup, and it does great for blasting around town on surface streets, and absolutely tractors through the desert sand. I'm with everyone else who said a bike like this will likely be too small to keep you safe on your commute. Maybe look into something bigger. Hope this helps.

[Noobie101]

How much trouble would it be to fet to 80 is need be tho? With the 16/39 gears and trying to keep it at 6k-7k
Would be doen a pod filter and the pz30 carb and jetting i have no idea yet im still prepping before i buy it still have some to save up..
Has anyone put smaller rims and tires not by to much maybe 2-3 inches smaller

[franque]

If you need to run 80, just get another bike. You might have to save longer, but with those flexible forks and mild steel frame, which are designed more for low speed maneuverability than for high speed stability, and relatively low weight, you'll be hard pressed to safely get the performance you want.

Smaller wheels won't help stability, better frame geometry/suspension will. It'll be tank slapper city if you try to maintain 80; even if you manage to eke out the power to maintain that speed, it'll cause extra mechanical wear from having to run it at 8k to (theoretically) maintain that speed.

Even a CBR250R would have an easier time of maintaining that speed, though you'd still be wringing its neck. I'd start shopping for a Ninja 250 or 300, and I prefer Hondas and dual sports.

[Noobie101]

I have many many stupid questions lol but thank you for chiming in on my thoughts as well as telling it straight up and being realistic ..

Tbh i only thouggt of the tbr7 for the comute as it was fairly cheap and iv read that when done right it is reliable..

Iv looked at the ninja 250 and the cbr250 as well and im a big fan and would totaly get one but funds are rare for me with bills i end up liveing day to day but i managed to get close to my goal and i still will be getting one as iv made up my mind and like the rest of yall.. i to will be working daily to make it as safe and fast and fun to ride as possible

[Noobie101]

Just how much of the hawk and tbr7 are interchangeable tho iv seen many things just swap over like the head and swing arm and much more

And i do apologize if i have ran this thread of course im very interested and totaly beside myself

[Megadan]

Well the real question is, do you want the bike to be a good dual sport, or is this mainly going to be a commuter bike? If off-road capability isn't really a primary concern there is a bike out there that gives you the same basic bike, but with 17" wheels and a counter balanced motor that makes for a much, much, much better road bike.

There are a few places that list it for sale, it's known as the CR250 or DB-47-250.
https://www.shopapmc.com/New-Bashan-Extreme-250-47-Motorcycle--Inverted-Shocks-Counter-Balanced-Engine-Free-Home-Delivery-wLiftgate-in-the-State-of-Georgia_p_71.html

[Noobie101]

Megadan.. it would be more of a comute bike but would love the option to be offroad as well as i can drive the truck till i get it right its only like 5-6 miles tho how much could it hurt to get the 17/34-35 gears and tweak carb and do all the mod this form has to offer?
Evan thought about the 34mm carb as well.. i would truely love to get
It to where i can dri mve this thing daily to work and back and have the truck as my bad weather day backup

[Noobie101]

Its nothing to swap gears over to make it more offroad friendly but they would be under the seat as a just in case thing

[CaesarVis]

I just wanted to post somewhere on here that the old gearing/speed calculator site doesn't work anymore. I just found the one below:

https://www.gearingcommander.com/