GZ 250 Forums - My GZ 's top speed seems low

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Re: My GZ 's top speed seems low

Quote:

Originally Posted by paulisnofun

Thanks for the advice Kcarvajal and B1pig. I will take a look at the throttle and clutch cable, and make sure they are just right. I dumped some carb cleaner in the engine hoping to clean the carb up a bit. Since I am not mechanical in any way, I probably shouldn't take the carb off and clean it.
One other question. When I ride to work and I am going around 45 or 50 and need to stop at a traffic light, when I stop the bike the revs seem really high. I mean really high. I don't have a tac, but it sounds like the engine is still running does when riding at a higher speed. That's not good, right? What could be causing that?

Likely a vacuum leak or the carb is hanging up. Does the throttle grip close smoothly by itself? The cables may need lubing.

Re: My GZ 's top speed seems low

I checked for a leak and couldn't find one. Checked all of the hoses and sprayed some WD 40 on the boots and connections. The throttle grip does close smoothy by itself.

Re: My GZ 's top speed seems low

Sure sounds like she is running lean. Check the plug color.

Re: My GZ 's top speed seems low

I am 6' 2" 230 lb my have similar problem before i mode the carb now I can cruse at 75mi and with good conditions 80+
my settings
main jet 140
pilot 3 turns
16T
mode air filter ( do not mode the filter without change the main jet )

http://s18.postimage.org/rl4jnh1f9/I...830_110644.jpg

Re: My GZ 's top speed seems low

Quote:

Originally Posted by Water Warrior

Quote:

Originally Posted by paulisnofun

Likely a vacuum leak or the carb is hanging up. Does the throttle grip close smoothly by itself? The cables may need lubing.

Agreed. Something is sticking....

Or

People have also complained of the carb boots (the rubber things that connect the carb to the engine) not being tight enough and letting in way too much air.

Re: My GZ 's top speed seems low

You said a number of posts above that you turned "that screw thing" and increased the idle because your biker stalled. You probably adjusted it too high, and that wasn't your initial problem anyway. That idle adjustment screw is only to be used when the engine has fully warmed up, and then set to about 1300 rpms, then you don't touch it again. Ride your bike, warm it up, and turn down that white knob until the idle sounds right, then leave it alone.
And make sure you are also not riding around with the choke on.
You may need the choke to start the bike after it sits a while and this is normal and may be why your bike would only run for a second and then stall, being up in cold Pennsylvania. As you ride and the engine warms up, slowly turn it down 'till it is off after a few minutes or about 1 mile of riding.

If you haven't yet, read the owners manual and it will answer and solve a lot of problems before you start making new ones. It can be downloaded off here if you don't have one.

Quote:

Originally Posted by raul10141964 (Post 65174)

I just picked up my GZ a week ago. I just got it over 65 for the first time and I have to admit I was a bit anxious. About how long are you able to hold 70+?

I installed a 16 tooth front sprocket and can reach 80 mph on my GZ barring any wind or hills, but with the stock 15 tooth front sprocket you should easily cruise at 60 mph for extended trips with the same caveats. Just remember that you are creating a lot of wear and tear on that single cylinder engine at those higher revs. Safe riding.