Bike won't run over 20 mph, sputtering idle

[Shipman515]

Hey ya'll.

My gz250 recently stopped running normally. The bike now sputters when in idle and will not accelerate above 20 mph. It sounds like it is not getting fuel properly (I've tried seafoam and another cleaner, but to no avail). Just curious where y'all would recommend starting to remedy this problem.

Edit: It's an 01 with approximately 8000 miles if that helps.

[alantf]

Have you tried running the bike in "prime"? If this gets it running normally, then your problem is a vacuum leak from engine to petcock. If you haven't already tried this, then give it a go, & let us know the result. :2tup: However, it seems to point to a carb problem.

[Shipman515]

Same behavior when run in prime.

[blaine]

Disconnect your fuel hose at the carb and see if you have good fuel,with the carb on "pri".If you have good fuel flow,than you will need to clean your carb.If you don't have good fuel flow,than your petcock screens are plugged.
:cool: :)

[Shipman515]

Which is an easier problem to remedy?

(I'm new to working on motorcycles).

[alantf]

Which is an easier problem to remedy?





I think you're missing the point. Easier or difficult - you have to remedy whichever the fault happens to be. :)

[jonathan180iq]

Also, check all vacuum lines.
A disconnected vacuum hose somewhere will cause this problem as well.

Being an '01, I would replace them all anyway.
Just head down to your local auto parts store and buy 2 little boxes of hose. There are only two sizes on the whole bike.

[Shipman515]

Could a fuel filter do this as well?

[Shipman515]

And how do I clean the carb? Do I buy some sort of fuel additive for the carb or do I disassemble it?

[jonathan180iq]

The fuel filter probably isn't the problem, but they are easy enough to replace and it's a good habit to keep an eye on it.

For carb cleaning, to do it correctly and thoroughly, you need to remove it.

To get a pretty good carb cleaning, pour in the proper amount of Seafoam or Berryman's b-12.

[Jvacustoms]

If you cant get it running I work in Greensboro, Ga and can ride up there when I get my brake pads in take a look at it.
I am new to motorcycles but mine has given me a good education on things that can go wrong first long trip go to Watkinsville, GA an the vacuum line popped off the petcock so i had to get a clamp from the guys at Boxerwerks They are behind Ducati and service all makes of Bike! Tell them I sent You the name is James Ammons "aka the guy that got a clamp from em when they opened on Friday morning about a month ago." Haven't known these guys long but they seem like some real nice guys, and are knowledgeable from what I can tell

[birdmove]

Has the bike been sitting for a while just before the problem happened? I'd suspect a plugged, or partly plugged, pilot jet. Doesn't take much tolug one.

JN