'82 GPZ 550 overheating easy / can't idle?

Hiya,

So I have an '82 GPZ 550. I finally got rid of most of the problems, fixed the rear signal lights, the horn, and got me a plate.

My friend and I were riding it around for a bit of practice (for me), and we noticed that it seems to have an overheating and idling problem. The problem is, after riding for 5 - 10 minutes and then coming to a stop, the bike would stutter (I'm not sure of the correct term, but the engine would just stutter and skip unlike running continuously in regular riding operation) and then stall. So...that's a problem for someone riding on roads with traffic lights, heh.

Any ideas on what may be causing this, or how to find out, and maybe how to fix it? Thanks!

My friend thinks it might be the fuel filter that the previous owner had unprofessionally installed, which he thinks is not delivering the fuel correctly. What the previous owner did was first connect a short tube (just regular tubes) to the fuel filter, because it's not long enough, and then the fuel filter to the carb.

Remove the fuel filter, it's unnecessary

Fuel starvation is one of several possible causes for the reported driveability problem, and might be caused by a malfunctioning vent in the fuel cap.

An easy method to rule out a clogged fuel cap vent is to test run with the cap ajar (not snapped down) to determine whether problem persists.

Imo, a fresh in-line fuel filter is a good idea. And there's usually an arrow to show the proper direction of fuel flow through the filter.

Good Luck!

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Patton wrote:

Fuel starvation is one of several possible causes for the reported driveability problem, and might be caused by a malfunctioning vent in the fuel cap.

An easy method to rule out a clogged fuel cap vent is to test run with the cap ajar (not snapped down) to determine whether problem persists.

Imo, a fresh in-line fuel filter is a good idea. And there's usually an arrow to show the proper direction of fuel flow through the filter.

Good Luck!

Thanks! I'll make sure to test that when I have time tomorrow or something. How would I tell if it's clogged or not, with the fuel cap open? Sorry, I'm new to motorcycle.

I'll definitely also get a new and proper fuel filter and install it the right way.


One off-topic question, I also need to change/add the fork oil in my fork, because it's getting way too low (just sitting on the bike makes the front fork goes down). Can I change the oil just at home instead of bring it to a shop, when I only have regular tools like ratchet, wrenches, screwdrivers and whatnot?

reinhart_menken wrote:

...How would I tell if it's clogged or not, with the fuel cap open?...

One off-topic question, I also need to change/add the fork oil in my fork, because it's getting way too low (just sitting on the bike makes the front fork goes down). Can I change the oil just at home instead of bring it to a shop, when I only have regular tools like ratchet, wrenches, screwdrivers and whatnot?

Running with the fuel cap ajar vents the tank regardless of whether the cap vent is functional or not.

A fuel starvation problem resulting from a clogged cap vent often disappears when the tank is allowed to vent through the loose cap.

Front forks usually have some normal "sag" from weight of bike and rider, which is primarily determined by spring condition (supplemented by air pressure where so fitted). Am thinking oil and viscosity thereof determines rate of damping, but not the amount of sag.

While front forks may be serviced with common tools, it's best to have a factory service manual at hand for the procedures involved, and so the spring free length may be verified within specified service limits for the particular model, along with oil type, viscosity and volume.

Good Luck!