Constant Frustration...Why won't it start!?

[nike_soccer]

1991 Yamaha FZR 600r

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I laid down my bike a few days after Christmas (in 2k5) and it hasn't been running since. 5 months with no bike, I'm pretty mad...Anyway;

At first, I just had to replace the clutch starter cover, because it was punctured badly in the low side. I fixed it. Still didn't run.

Cleaned the carbs, still doesnt run.

Had a blown fuse, so I repalced it, wouldnt start.

Got a new battery wouldnt start.

Starting relay got shot out, so I replaced it, still wouldn't start.

All my sparkplugs fire, I've tested them. My engine turns over, and sometimes if I'm lucky I can get a backfire.

I've tried doing a running start and popping the clutch in all gears.

I'm so lost...I'm about to take it to a shop, and just let them sort it all out, and pay a hefty fee...

[TechTMW]

I worked on a similar bike where everything was OK ... but the bike wouldn't start. Puzzled over it for a few hours. Then by chance I discovered the problem - The Idle speed screw was backed out of its socket.

I'm not saying this is your problem, just that sometimes it's just something so glaringly simple that you miss it

[Tyrone ORourke]

Just a general tip for motorcycle maintenance:

If the engine won't run(and you dont suspects any internal damage) it is likely down to three possible problems:

Air supply
Fuel Supply
Spark System

Since your sparks are fine, look at the air system( which should be ok, but u never know, I had a bike which I was doing some touch up spraying on, stuffed a rag down the air intake, and then layed the bike up for a few months, forgot about the rag and come time to start her up, she wouldn't)

Most likely then is the carbs, check that all the settings are right.

[CORSCO]

I don't know why this would happen after you laid it down, but FZR600's have a bad case of soft valves. High mileage bikes where the valve adjustment was neglected will have valves that have pretty much pounded themselves into the head. This will cause the valves to be tight and will have pretty much distorted the seats. The valves pretty much mushroom themselves out, no more sealing angles and the edges become razor sharp.
I had one where I did a valve adjustment, they were all tight, got them right, ran it, checked them again and they were way off from my original settings. Nothing to be done but replace the valves and recut seats.
I hope this is not your problem. Check the valve clearance or do a leakdown or compression test to see. Good luck.

How many miles are on it, anyway?

[nike_soccer]

As for the engine's miles, I'm not sure, when I bought it, it didn't have an instrument cluster.

Also, my carbs are nice, but I dunno about the jets, they seem fine. When I put fuel in the opening of the carbs ( a little bit of gas ) the engine will crank and backfire.

My air filter is clean, and airbox is sturdy.

As the for the idle screw, I think that could be it. One of my buddies thought that it was an issue ( and it kinda was ) so he told me to screw it one direction, and then try, and then another and try. I got lost on how many turns was which way and what not...

How can I test the idle screw thing? Is there a way to reset it? How do I fix it?

[nike_soccer]

bump

[NorthernPete]

I dont knwo if youd be able to reset the idle screw without the machine running.

[nike_soccer]

can a motorcycle shop even fix that?

[old-n-slow]

check th etimeing. It could have gotten screwed up.

[TechTMW]

Try screwing the idle screw all the way in and then backing it out in 1/2 turn intervals each time you try to start it.