Kawasaki Sportsbike Riders Club - Australia - Online Forum

My son's GPX250 ('04) - 13,440 km - is getting a bit sluggish.

It is OK in the morning when it is reasonably cool, but in the afternoon, when the weather is hotter (32+ degrees here) the engine becomes sluggish. Today, with 35 degree heat, he said that the gearbox is getting noisier and notchy as well.

My guess is that the oil is too hot, and also that blow-by via the crank-case breather is causing the carbs to suck in other than fresh air.

Am I right?

Thanks,

Bill.

Last service was when? And what was done?
New oil may improve the gearbox. Valve clearances and a carb balance may improve the rest.

maybe the hot weather is making the bike run hotter, and the oil thinner or sumthin??

my bike runs better in colder weather- more air when its colder and denser... can run like a pig in the heat...

yea.. when was last service etc??

plus.. its a gpx.. they are sluggish at the best of times...lol

Has the air filter ever been cleaned? If it's running rich due to a restricted air filter it will get worse with higher air temperatures.

Last service - last month. New oil (Motul 15W50).
Air filter: K&N, clean.
Valves, carbs etc all serviced/adjusted/balanced.

I may disconnect the crankcase breather hose from the airbox, see if that makes a difference.

This GPX sluggish? Not for a 250, it usually goes like the clappers.
Thanks,

Bill.

billwest wrote:Last service - last month. New oil (Motul 15W50).
K&N, clean......... Valves, carbs etc all serviced/adjusted/balanced.
Bill.

Bill did you do it yourself ? or ARE your ASSUMING it was a "some intrigal component of trading Money for services arrangement" ?
sounds to me like the Armour ALL has worn off the seat from the LAST service.

LOL!

I did oil, filter, airfilter myself.

WA top dealer and service centre, Mack1 Kawasaki, did the rest! Oh ye of little faith! The bike did come back very clean, though...........

41 degrees here in Perth yesterday, and it actually ran quite reasonably.
Will post when I have found the solution, which won't be this weekend, 'cause I'm off to the Superbikes at Phillip Island.

Bill.

tis a 250, enough said

Safe trip Bill,
I've seen it done mate, The Armour all service it's called. Overbooked day, staff member short & no overtime.
"She'll be right, mate."
Let us know if you find anything, ta.

dude had a similar prob
chack that you havent over filled the bike with engine oil .
when i bought my 250 it had to much oil in it and it was idleing rough and also the throtle responce in the high gears at low revs wasnt there.
so i decided to drain the oil out and put the correct amount in and its like a different bike

Gazza

All is good now. I think it may have had a clogged vent hole on the tank. and it was especially noticeable when the weather was hot..

Bill.

billwest wrote:All is good now. I think it may have had a clogged vent hole on the tank. and it was especially noticeable when the weather was hot..

Bill.

Good to hear it was an easy fix Bill ... that wont happen again now will it
Does the bike wistle when the tank gets hot? its a good sign when she goes quiet

robracer wrote:

billwest wrote:All is good now. I think it may have had a clogged vent hole on the tank. and it was especially noticeable when the weather was hot..

Bill.

Good to hear it was an easy fix Bill ... that wont happen again now will it
Does the bike wistle when the tank gets hot? its a good sign when she goes quiet

My Gumby has always whistled when the tank is hot?? blocked breather??

Performance varies from fast to farkin woo hoo !!! (suppose extra 750cc's makes it less noticeable!?)

Sounds like you been here before rob?

Can't be too hot in Kambalda at the moment, eh?

The Freo doctor don't do much by the time it gets here LOL

Bike tank still talks to ya after a decent ride though!?