Whats your max speed (flat)

[FoxMcCarther]

Hello, I've been stalking these forums for a while now, and I feel like my bike is a bit slower than many of the numbers I read here (granted not by much).

So, What are the max speeds (no incline or decline) your bike can reach in a reasonable amount of time (under 20 seconds or so in 5th gear), and what is you max downhill speed.

Also, I am not yet a very mechanically inclined person (getting better every day though), but what relatively simple things could I do to coax an extra 5-10 mph or so out of the bike all around (I'd like to be able to go along at 60-65 a bit more smoothly (I plan on installing the 16t front sprocket soon (which will help a bit with the smoothness and speed on the flats and downhill, but reduce my uphill speed a bit in 5th? (In theory, shouldn't it add ~2-3 mph on flats?)), but beyond that, what easy things can help?

I am aware of the performance mod section here, but I don't yet understand what some of them actually effect.

I am 5'10" at 175lbs, the wheels are stock, my 'average' max speed is about ~62 mph (struggles to keep up at 55 at anything more than an incline), the fastest I have been able to get it (downhill, wind at my back) was 74mph.

[JWR]

The GZ that I had would do 75 + everyday.

You can wind it out in 4th and should be around 70.

A 16 tooth sprocket will not give you more top end speed.

[jonathan180iq]

My max was right around 80mph +/-.

Your bike can go faster than 62mph. Don't be afraid to work it up a little bit. For a thumper, these bikes are pretty rev-happy.

If you have any questions about the performance mods section, just spit it out. There are some areas where common-knowledge items are left off, but we'd be more than happy to explain those to you. That being said, this bike is only ever going to go so fast. You'll never hit 90 mph on a GZ250. 16T front sprocket, intake and exhaust mods with proper jetting will net you 80mph... same as factory.

If you want to do anything, make sure your tires are aired up, your oil is fresh and filled, your chain is adjusted and, if you really want, raise the needle jet slightly to increase fuel flow in the mid range.

[Kcarvajal]

Mine can do 80+ also. My bike is all hacked up, 16T front sprocket, 18” rear wheel with 38T sprocket, Main jet to 145, needle shimmed, straight pipe, open air filter etc. I have a digital bike speedo which I guess I need to properly calibrate. I was cruising at 65mph comfortably with some throttle left and was told later that we were doing 70+.

I also recently joined a bike run of about 30+ riders. My bike was the smallest displacement and was keeping up comfortably with the rest of them. In my opinion they were flying!!!

Here’s the vid from the run. At around 0:46 (tail end), that’s me creeping up from the bottom-left of the video… tank with orange stripe.



Ken

[jonathan180iq]

Hey cool vid, man!

[Kcarvajal]

That was so much fun! I'm ready for another..

[Water Warrior 2]

You were certainly travelling with some fast company. I'll bet some of the other rides were surprised at the GZ.

[wee228]

After lowering my 2005 gz, using open ended exhaust, open carb, really low salt flat style handle bars, slimmer sportster gas tank, no speedo, no fairings or plastics, no fendersfeet on my rear pegs, chin to the tank, open smooth road, 100 low lead fuel(avgas) .. I hit 95 mph. Of course with my buddy next to me on his sportsbike tracking my speed. :lol: :rawk:

[raul10141964]

140 main jet
needle shim
open air filter
16T sprocket

cruse 75Mi flat 80+

[TheHornsmith]

I just recently bought a 2001 with low miles. I have gotten it up to 75 on flat smooth road. and chickened out at 81 going down a long hill. it maxed at 68 going up a medium incline. i think with a long stretch of smooth road i could hit 80 on flat ground. this is all stock with a light pack and i weigh 146 with my gear and my helmet.