2004 w/82k miles Will not idle

The bike starts fine and will stay running if slight throttle is applied. The second the throttle is released the engine dies. Will re-fire immediately but continues to exhibit the same problem. Even once the engine is warmed up the problem persists.

Happened out of the blue.

Bike was stored for the winter, removed from storage, then ridden on a few occasions with no problems.

This started happening after a very short ride of a few miles. Rode for about 3 miles, parked the bike for about 2 hours, went to ride home and the problem started :scratch

Rides normally so long as the throttle is never returned to full off.

Any ideas of where to start diagnosis are appreciated.

Idle speed setting? Try 1100 to 1200 rpm.

Check battery connections as well as plug wires fully seated.

Corrosion in big connector under tank? Photo stolen from another post...

Gravy, Missed seeing you lately!

+1 on raising the idle to 1150 or so. I store the bike w/ Chevron Techron and/ or seafoam in the gas. Maybe add some now and 'blow the carbon out of it'.

CU on the Spring ride?!?!

Idle speed. Connector referenced above. TPS.

What happens when you start it cold? Idles 1500-1800 ? Then slowly drops? Is it higher -lower ? Turning idle screw opens throttle plates. Any air passing plates will raise idle speed.

Need more info.

Hey Roger! Family is cutting into my riding time these days. You know the drill.

I did try messing with the idle speed mostly in an effort to keep it running for the ride home. You can sort of mask the real problem with that but there's more going on. It was stored with fuel stabilizer and besides that it's on a fresh tank so I really don't think fuel is the problem.

I took that connector you pictured apart. Everything looks good. No corrosion or obvious pin/socket damage. I gooped it with some dielectric grease just in case. Problem persists.

It never does go to high idle upon start up. On a cold engine: it fires, lopes along for a few seconds then dies.

I can keep it running by applying slight throttle but even once warmed the engine will die if the throttle is released. Unless I turn the idle up way too much. Then it will race at 1500 or so seemingly forever.

That's not an acceptable 'fix' for me.

Thanks for the input. This one has me baffled. A friend from another forum suggested a vacuum leak somewhere.

A defective TPS can cause this symptom.There was a recall about..

Ηave you ever replaced this thing?

Also,have you installed a Powercommander on?

Just put it into diag mode. TPS numbers are good. Starting number was slightly high from adjusting idle up but came down to normal range when twisted back to starting position.

Still searching.

No power commander

Diagnostic mode might not be a good indicator of TPS health. Could look smooth and with good continuity while testing but things may change with heat and vibration.

Doesn't sound like a TPS problem.. I had a bad one didn't do that, just a mis stumble opening throttle. I would bet on a large vacuum leak.

If it was fast idle valve it would idle when hot off base setting. The idle screw.

I'm hesitant to toss a $150 part at the problem.

Searching the interness brings up mention of a 'wax motor'. Something to do with the coolant and controlling idle speed based on flow and temperature. The information I've found has been less than stellar but a coolant flush wouldn't hurt and there's a remote chance it could help

:dunno

This one's a strange boy. Maybe it's time to get my old cx500 back on the street. All the complexity of a hammer.

Wax motor -valve controls fast idle. Cold idle. After warmed up the base idle screw sets the idle speed.

Its not a motor as in electrical type.

Any engine noises before after-this happened. something rapping rattling??

The bike has had what I would call top end noise since I've owned it. I replaced the cam chain tensioner a couple years ago and it quieted down some but has progressively gotten louder again.

Skipped tooth on timing chain?

I hope not but I suppose anything's possible.

Is the sm easy way to check?

So...

Is this skipping teeth a thing on these or are you just spitballing possibilities?

Doesn't seem like the kind of thing that just happens out of the blue.

You had mentioned some noise that might have been cam chain related. Doesn't seem likely that the CCT gave up again since you had already replaced it but you never know. A skipped tooth is going to be the result of a faulty CCT or an error in reassembly after a valve check or similar service. Doesn't randomly happen and is not common except as stated above.

Damn! Was really hoping to post here and have one of the salty members holler at me to do a search because it's x,y, and z and we've covered that 1000x.

Maybe call me a noob and end his post with a pissed off smiley.

Just like the old days of bike forums.