Cold idle at 4,000 rpm's! Need help!

2005RedRider

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:eek: When I do a cold start up of my 2005 ST, it idles at about 2,000 rpm's for about 1 1/2 minutes. By the end of 2 minutes it roaring at 4,000 rpm's. After about 8 minutes it begins working it's way down to normal "warm" idle of about 950 rpm's.

I've put a new thermostat in and flushed the cooling system. No joy! :mad:

The only thing that I can guess, is that the Wax Thermal Valve (SE Thermal Valve) is bad. I don't understand why it will go from 2,000 rpm's to 4,000 rpm's.

Has anyone else had this problem? What is the solution? I'm at a loss.:confused:

Any help would be greatly appreciated.

Thanks in advance,

Dale :(
 

STArnie13

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I haven't heard of that happening. It must be a sensor of some sort that is bad. I would have the dealer check it out as you should be under warranty.:03biker:
 
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2005RedRider

2005RedRider

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:D I believe I've resolved the problem. What caused it is beyond me. :confused:

Here is what I did to resolve the problem:

1. DAY ONE: Once the engine was dead cold. I opened the upper gas tank and removed the air intake chamber along with the rubber intake tubes in order to access the throttle body area. I started the bike. When it climbed to 4,000 rpm's, I adjusted the lock nut at the end of the SE Thermal valve shaft until the rpm's dropped to 2,000. I let the bike warm up to operating temperature and it eventually idled down to about 950 rpm's, I shut the bike off and waited until the next day when the engine was dead cold again.

4. DAY TWO: I started the bike. It's cold idle never exceeded 2,000 rpm's, and eventually reached operating temperature at 950 rpm's. I shut the bike off.

5. DAY THREE: I started the bike. The cold idle never exceeded 2,000 rpm's. Once it reached operating temperature, I took it for a 200 mile ride with an ambient temperature of about 52 degrees F. No problems.

I don't know why this adjustment had to made ... but it worked!:cool:

Dale:biker:
 
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This is exactly what my bike is doing. I just noticed it over the past few months. I'll have to try the adjustment you did. I'll keep you posted.
 
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I am a new ST13007 owner of just about 5 weeks. 3200 mi on the machine to date. I had the warm idle set back by the dealer. It was about 1250 and we took it to 900 rpm with the small screw/black knob on the right side just over top the cylinder head.

The temp has been around 32 deg F for the past few mornings and the fast idle does seem fast at about 2500 rpm. After the bike is hot, shut off and restarted, the idle never exceeds 1000 rpm. Since the bike is so new, I'll take it back to the dealer for adj, even though I am basically a do-it-yourself kind of person. I am thinking these Honda's won't need much adjustment or maintenance (formerly a BMW owner that had to do a lot of work on the bike).
 

ST13Fred

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I did the thermal valve adjustment today. Temps in 40s, air outside damp and cold feeling. Had no fastener incidence during the process.

Am very happy with the final result. I marked a flat on the 5mm nut as a starting point and turned in out (cc) 2-1/2 turns.

On my 04, if I let it cold idle w/o riding, the revs stayed manageable. But if I get on the bike right away, which I always do, the revs go way high when I pull the clutch, after riding away, until it warms up a bit.

Now the revs never got above 1800, which is perfect and the warm up a full temp idle was normal. I want to get it out in a 20s morning for the real test.

:04biker::D
 
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I did the thermal valve adjustment today. Temps in 40s, air outside damp and cold feeling. Had no fastener incidence during the process.

Am very happy with the final result. I marked a flat on the 5mm nut as a starting point and turned in out (cc) 2-1/2 turns.

On my 04, if I let it cold idle w/o riding, the revs stayed manageable. But if I get on the bike right away, which I always do, the revs go way high when I pull the clutch, after riding away, until it warms up a bit.

Now the revs never got above 1800, which is perfect and the warm up a full temp idle was normal. I want to get it out in a 20s morning for the real test.

:04biker::D
Cool, I'll be doing this soon also. I don't wait till 1 bar shows to ride it either. warming gets 0 mpg. I just start it and take off. I do baby it till fully warmed up though.

Does the thermal valve push or pull the mechanisim open? I'm amazed it took 2.5 turns to get it where you wanted it.
 

ST13Fred

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Does the thermal valve push or pull the mechanism open? I'm amazed it took 2.5 turns to get it where you wanted it.
It appears it is pulled open. Turning the nut counter clockwise releases the mechanism, closing it. It doesn't move w/throttle action, so am not sure how it affects throttle position, but apparently does.

Red Rider Dale said 2 turns gave him 2K RPM. I went 2.5 turns thinking even a 1500 RPM cold idle is OK. This V-4 motor is smooth and could probably warm idle at 500 RPM with no problem. I started the bike before closing things back up, just to be sure I didn't go the wrong way w/the adjustment.

Good luck.

This is a P.S. to the above, 09 Dec 08. At 50 degrees + I do know my bike will not fast idle. Perhaps something less than 2.5 turns may be better, but it warms fast and will hold idle, if I'm careful.

:04biker:
 
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2005RedRider

2005RedRider

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Re: Cold idle at 4,000 rpm's! Problem Solved!

My 2005 ST1300 began a warm-up high idle problem last winter. This means that it would the warm-up high idle would run up to 4,500 rpm's for about 4 to 5 minutes. This is way too much, for way too long! It should have a warm-up high idle of about 2,000 to 2,500 rpm's, for no more than about 1 minute to 1/2 minutes (depending on how cold the ambient temperature is).

I also found, that even after it finally idled down to the normal 1,000 +/- 100 rpm's, I still had a problem. If the ambient air temperature was below about 45F, when I would come to a stop and pull in the clutch, the idle was high again (4,000+ rpm's).

Since I don't trust the STealers, I've been working on the problem for about 1 year now.

This is how the warm-up is supposed to happen:

1. When the ambient temperature falls below whatever solidifies wax, the wax inside the SE Thermal Wax Starter Valve (SETWSV)will solidify and contract.

2. The contraction of the wax will pull in the valve plunger and shaft. As a result, this will open ports on each of the throttle bodies via linkages.

3. When you start the engine, the butterfly vavles in the throttle bodies are closed, so now the opened ports allow air to enter the throttle bodies and mix with the fuel. Without this, the engine would be "choked" and wouldn't start.

4. Once the engine is started, coolant begins to flow through the hoses connected to the base of the SETWSV. As the engine begins to warm-up, the butterfly valves begin to open, and the wax in the SETWSV begins to melt and expand.

5 As the wax expands in the SETWSV, it pushes the valve plunger and shaft outward and starts closing the throttle body ports. (If the wax doesn't expand, the ports will not close and the increased volume of air from the opening butterfly valves and the open ports increases the rpm's excessively.)

THE PROBLEM SOLVING BEGINS:

I started by adjusting the nut on the end of the SE Thermal Wax Starter valve. This reduced the rpm's at warm-up, but then I couldn't achieve the necessary high (2,000 to 2,500 rpm's), dropping to the normal 1,000 +/- 100 rpm's. I adjusted the nut back to it's original position.

I then tested to see if the SETWSV was actually functioning. I applied heat directly to the SETWSV with a heat gun. The valve plunger pushed out. I applied cold with a lot of ice directly to the SETWSV. The valve plunger pulled in. Conclusion: The SETWSV was functioning correctly!

I knew that when the ambient temperature was cold the valve plunger was pulled in, but as the engine warmed up, the plunger didn't not readily push out. So, this meant that there must not be any warm coolant running through the hoses connected to the SETWSV. The wax was only melting as a result of heat rising off of the engine, and as I rode a few miles in the cold, the SETWSV was no longer being exposed to the engine heat. It was exposed to the cold ambient air - causing it to contract and pull in the valve plunger.

Since the warm water for the SETWSV comes from the warm/hot water outlet fittings on the top of the engine, just underneath the throttle bodies, there must be a clog or a kink in the hose. I dreaded disconnecting the throttle bodies and lifting them out. SO I DIDN'T!

When you look at the attached image, called the SYSTEM FLOW PATTERN, you will see that SETWSV hose outputs to a "T" fitting, and then to a fitting on the right side of the radiator, just under the radiator cap.

Before starting the engine, I removed the right-side fairing. Then I removed the radiator cap. I started the engine. You should see flow inside the radiator neck at the fitting mentioned above. Next, I clamped the hose (as shown in the attachment), to isolate the flow from the engine, so that only the flow from the SETWSV would be visible. Guess what? - NO FLOW! Aha! My suspicion is correct! Now what do I do? :cool:

Here's what I did:

1. I turned of the engine.

2. I disconnected the hose at the radiator fitting, and connected a brake bleeder suction device to the hose. No matter how much suction I applied, I couldn't get any coolant into the hose. NOW WHAT?! :mad:

3. I turned and saw my air compressor, and a crazy thought entered my mind. If I can't suck it out the clog or kink, maybe I can blow it out! I started my compressor and waited until it reach 160 lbs. I put the blower fitting of my compressor into the hose and squeezed the trigger ... what a mess! Coolant shot out of my open radiator - all over me, the bike, and the ceiling of my garage! What and idiot! :eek::

4. I reconnected the hose back onto the radiator fitting. With the other hose still clamped. I said a little prayer and started the engine. SUCCESS! I now have flow through the coolant line for the SETWSV! :D I let it run for about 20 seconds to purge any air, and shut off the engine.

5. I cleaned my glasses, mopped the bike and the garage floor. Then I removed the clamp from the other coolant line, and reinstalled the radiator cap.

6. I drove to the Honda (car) dealer and bought the pre-mixed blue honda coolant, and refilled the radiator. That's what I have used since I replaced the thermostat about six months ago.

7. With the engine still cold, I started it up. It high idled at about 2,100 rpm's for about 1 to 1/2 minutes and then eventually dropped down to about 1,000 rpm's.

8. I thoroughly cleaned the bike and took it out on the interstate for a 40 mile round trip test. The ambient temperature was 37F. I tried pulling in the clutch several times. It maintained the normal 1,000 rpm low idle!

Unfortunately, I don't know if there was a clog or a kink. I don't know if it will come back. But for now, I'm one happy ST1300 owner! :D

Dale
 

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Joe
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Also, did you refill the radiator or do another flush? Just wondering if whatever was clogged in the first place is still circulating.
 
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2005RedRider

2005RedRider

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Mellow,

I got tired and lazy. I just did a refill. If it happens again, I'll go through the same procedure and also do the flush.

I rode about 60 miles yesterday with no problem.

Fingers are crossed. At least it's not a problem that would disable the bike.

Dale
 

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Joe
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Understood.... maybe if you're lucky whatever it is will end up in the bottom of the coolant bottle.
 
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Dale,Great Stuff ! You should think about holding a tech session to teach owners your mental approach to problem solving. Don't know what your background is but your methods are faultless. Thanks, Angus.
 

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Very intersting... Since installing my Audiovox CCS-100 Cruise, my cold idle has been about 2,500 until warmed up. I had read of others making this adjustment after the Cruise install...perhaps I'll tweak it and see if I get a more comfortable 1.8k-2k cold idle.... :headbang:
 
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