2006 gz turns but won't start.

[BonChaton]

Hey Everyone,
I have a 2006 Gz with about 17,000 miles.
My bike slowly developed a starting problem over about 3 weeks going from starts up no problem, to a bit harder than usual to start, to does not start. :??:

1) It turns over no problem, and air puffs out of the exhaust.
2) I charged the battery up the best I could. It didn't seem to act any differently. Also, I got busy and couldn't work on the bike for 10 days. I went to try to start it after all that time, and it was only too happy to turn and turn and turn. I don't notice any big dimming of the headlight when it turns either.
3) Took a quick look at the carb today and it looked squeaky clean inside. Although a more thorough look may be necessary.
4) The fuel screens on the intake in the gas tank are nice and clean.
5) The spark plug sparks with no problem.
6) I use the choke when I try to start it. I always have.
7) I can get it to roll start if I get it rolling pretty good, although that's getting harder to do too. It runs ok once I get it going. However it idles a little rough and kind of wants to die at traffic lights. I also noticed in the weeks that it was getting harder to start, that the idle was getting a little rough along with it.

I saw the post for the 2001 gz before this one. I'm going to see if one of the jets got slowly clogged. It seems to me I have air and spark, and gas is all that's missing from the equation. I was just wondering if anyone else had an cool input.

- Thanks All
BonChaton

totally bummed my bike won't start :(

[BonChaton]

Took the carb out. Took a look at the jets. Cleaned them out with a little B12.
Put everything back together.
Turns but won't start.

Roll started it. Fires up and runs well. :skeptical:

Annoying. :tdown:

Does anyone know much about the ignitor? I'm guessing I'm going to have to go after the electrical system. Maybe the ignition spark is just not getting timed right due to a faulty ignition circuit.

I have the following theory. When I roll start the bike, maybe when I pop the clutch the ignition circuit gets cut out because the clutch lever is open - the ignition circuit stops screwing up the timing - the distributor takes over the timing and the bike starts. :crazy:

[alantf]

7) I can get it to roll start if I get it rolling pretty good, (

Just a thought - clutching at straws, really - but it occurs to me that by rolling it, the engine is causing suction to open the petcock. Have you tried starting it in "pri"? If it starts, then you have a problem with the rubber pipes to the petcock. As to your suggestion about the ignition circuit, it's got me really stumped. Could be, but it sounds unlikely. However - stranger things have happened. :??: It really sounds more of a fuel problem than electrical. As a general rule of thumb, if it's an electrical thing, the bike will either run or not. A fuel fault will cause rough running. Carb cleaning is not my area of expertise, so perhaps someone could come in at this point, to explain if there's any more bits of the carb that you should check.

[jonathan180iq]

Agree with Alan.

If there was an electrical issue, you wouldn't even be able to roll start it. It wouldn't even come close. Now, if the bike smelled heavily of gas and didn't start, then we would assume something electrical, but that's not the case.

Test it in PRI.

[sqrimp]

hey bon, in reply to your question about my issue, mine turned out to be the pilot jet causing the issue. a quick clean out and running some carb cleaner through the lines did the trick. looks like it wasnt any help to you though :(

[raul10141964]

install a new spark plug

[alantf]

install a new spark plug

He said "the sparkplug sparks with no problem". :)

[raul10141964]

a bad sparkplug will spark off the engine but with misfire when instale

I kep a spare on the bike

[BonChaton]

I have to check closer for a gas smell.
After playing around with the carb, there is gas all over the place and its hard to catch gas smell from the bike.
Although I can tell you, when I open the float bowl drain to work on the carb there is plenty of gas in it.

Here is the weirdness of the weirdness.
I roll start the bike and ride it around. Everything is fine. Maybe a little stuttery on idle but not too bad, especially after it warms up.
I stop and turn the bike off.
Two seconds later I try to start it.
It turns and turns and turns but doesn't even cough once. Not even one pseudo - start. Nothing but turn turn turn. :shocked:
But if I roll it again - vroom. Starts right up again. :skeptical:

I guess when the engine is running maybe there is enough vacuum to overcome a cloggy carb, which starting might not be able to overcome.
I might try to drop some carb cleaner into it and take it on a long spin to see of it gets any better.

The ultimate of confusion to me though, is that when I try to start it, regardless of conditions, it doesn't even get close to firing. Not even one cough. sputter, skip. nada. For a bike that will run, something about that screams 'bad timing on start' to me.

Thanks for your comments. They have me thinking.

More later.

[alantf]

Dunno what Suzuki are playing at. My mate's got a Suzuki 125cc scooter. Even that's got FI. But they could never instal it on the GZ. Oh well..... :??:

Remember that the carb is the achilles heel of an otherwise decent GZ. You'll find that once you get it running, you'll need regular doses of carb cleaner in the tank to keep it in tip top order. :)

[jonathan180iq]

I think you're sniffing the right dog's ass, about vacuum.

You alluded to bad timing on start, which can be marked off easily enough by checking the timing and doing a valve adjust if necessary. But, if that were the case, it would also be difficult to start when rolling it. (Harder than normal, I mean.)

Since she seems to run fine after you get her going, I still feel like it's vacuum. (You mentioned sputter and slightly off at low idle)

Drain the tank down to maybe 1/4 or 1/2 and run a high concentration of cleaner. Like you said, roll start and give her a good stretch. I would even pull those vac lines and blitz the inlets with a shot of the stuff too.

Once that variable is completely eliminated, if it doesn't solve it, you can move onto something else, like the timing.

[schooler94]

Try seafoam in the tank. And check the air filter, maybe it starts when its rolling because more air is getting in, but its too clogged when just sitting

[Road_Clam]

A quick test to see if you have a restricted fuel flow issue is to yank the air filter and spray some starting fluid into the intake. Start the bike, if the engine quickly starts, then dies, you have a fuel flow issue. I'm thinking you have a sticky carb inlet needle. Ethanol is notorious for causing inlet needles to stick.

[jomama]

Just a thought here. Is it possible the starter motor is drawing to much juice ? There may be enough juice to for the plug while ontside the engie and just laying on the block for a ground but not enough for it to fire under compression if the starter is drawing to much.

[Water Warrior 2]

Just a thought here. Is it possible the starter motor is drawing to much juice ? There may be enough juice to for the plug while ontside the engie and just laying on the block for a ground but not enough for it to fire under compression if the starter is drawing to much.
Excellant thought. Get another plug and screw it in. Repeat the spark plug test with the hole plugged and creating compression. Do make sure the battery is fully charged for best results.

[BonChaton]

Here is an update.

Tried a million things.
Checked electrical stuff. Cleaned carb. Charged battery. Yada-yada.
Gave up. Took bike to repair shop that works on Suzuki's.
They traced the problem to the exhaust valves not closing.
Estimated lots of $$$ for a repair.
Decided to get a new bike instead.
Bought a new-ish 2012 Suzuki Boulevard S40. (It is awesome to ride!)
Was going to trade GZ250 in.
Went to finalize deal with pink slip in hand.
However suddenly found sales was not going to cover the repair costs incurred up til then.
Kind of made bike not worth trading in.
Decided to have shop fix bike and sell it myself later.
Will update again when I have precise info on the repair.

So anyway ...
Now I have two bikes! :rawk:

[Water Warrior 2]

Cool, the S-40 is a nice bike. Just a bit heavier than the GZ with a bunch more engine to play with. One nice feature is the belt drive rather than a chain. This makes things a lot more difficult if not impossible to regear the bike but Suzuki is pretty close with their gearing on most bikes. You will probably like it as is.
Have fun and post some pics soon.

[alantf]

They traced the problem to the exhaust valves not closing.

So, did they say what might be causing the valves not to close? Did they even try to adjust them? There's a lot of "ifs & buts". Something doesn't smell right here. Is there another shop you can take it to, or even a friend who can help you to try adjusting the valves? :??:

[jonathan180iq]

Or do it yourself:

viewtopic.php?f=8&t=5061 (http://gz250bike.com/forum/viewtopic.php?f=8&t=5061)

[mrlmd1]

Why would the bike start with a roll start and run fine and not start with the ignition switch and starter turning it over if the "exhaust valves were not closing"? That makes no sense. Go to another shop and get the valves adjusted if they're out of spec, or do it yourself.
Or just go out and buy another bike.

[Water Warrior 2]

A bit strange. I wonder if the ignition system is weak and tends to fail when the starter is drawing power. You have proven the bike runs with a push start so everything else seems to be in order. Valves not closing sounds like some one is grasping at straws. I would be looking at E-bay for a replacement on the cheap.

[blaine]

If the valves get too tight,it will cause the condition you describe.When the valves are out of spec you don't have enough compression for the bike to start on it's own.But will start on a push,because the engine is spinning faster.Not saying this is your problem.But the first sign of valves too tight & needing adjustment,is hard/no starting cold.Valves usually get tighter with use, not looser.As the valve & valve seat wear,the distance between valve stem & adjuster decreases.
:) :cool:

[BonChaton]

Before I took it in, I checked the valve adjustment several times.
I even tried making them slightly loose to make sure the adjustment wasn't the problem.
I have a feeling that the person that owned the bike before me just rode it for a long time and never adjusted / maintained anything.
The valves may be burned and poorly seated and not closing fully.
I had to get it rolling at a pretty good rate to get it to start before I took it in.
It may run with bad valves, just at a loss of horse power.