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Discussion Starter · #1 ·
Hello everyone,

If there is already an existing thread on this, I apologize. Please direct me to it.

No mods that I'm aware of - just a Big Gun exhaust. Waiting for my TPS adapter to arrive so I can test the voltage. K&N air filter, while I wait for the OEM to arrive. Spark plug gapped correctly. Just replaced fuel filter with a brand new one.

Choke is 22 clicks to the left, and needs a little throttle to get going - and even then, it won't always idle by itself if I let off. When I can get it to idle, its starts to idle really fast after about 40-60 seconds. Also, as soon as I push the choke back in, it shuts off immediately. What should I look at next?

Also, I think I can get it to run a rough slower idle with the airflow sensor unplugged. Is this weird?

Thanks in advance!
 

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Can we post videos on these threads? I would think that would be helpful, no?
Welcome to the Forum...!!!

Make sure your battery is fully charged 12.8v standard

Yes you can post videos here from video platforms like youtube & provide a link to your thread...Video posted below

Yes, check your TPS to be in range, when the adapter arrives..!

Check if your ECU is OEM or procom..? OEM circled in pic..

OEM ECU you can't touch the throttle once the key is turned ON & motor is running...will cause the TPS to be out of range, FI error & force into limp mode will not run/start...!!!

Does your F.I light remain on or flashing when trying to start...?

Make sure your vehicle down sensor is mounted with arrow pointing up..!

Low compression can cause your symptom due to valves needing adjustment.. see pic for location

 

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Discussion Starter · #5 · (Edited)
While I'm checking these things, is there a certain amount of clicks the idle knob should be set at, as a starting point?

F.I. light was staying red for a couple of starts, after I reinstalled the fuel filter. But it went away. Only comes on for the first 3-4 seconds now, when I turn the key to ON.

ECU is OEM. Vehicle Down Sensor is sitting correctly in the slot, in the upright position.
Motor vehicle Electrical wiring Gas Auto part Wire


I can get her started with the idle screw pushed in at 22 clicks, but I have to hold the throttle in just a liiiittle bit, otherwise she shuts off.
 

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Discussion Starter · #6 · (Edited)
Also, I'm not following you:

"OEM ECU you can't touch the throttle once the key is turned ON & motor is running...will cause the TPS to be out of range, FI error & force into limp mode will not run/start...!!!"

I'm obviously missing something..., but if the motor is on and running, that means the key position is also on - how would someone be able to drive the bike without using the throttle?
 

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Discussion Starter · #8 ·
I can get her to run, 22 clicks, pushed in, on cold start. Making some progress on identifying the issue. I think the radiator fan wire is melted - its not coming on, and the cooling system doesn't seem to be working properly. Maybe that's why she is not starting when hot?
 

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I can get her to run, 22 clicks, pushed in, on cold start. Making some progress on identifying the issue. I think the radiator fan wire is melted - its not coming on, and the cooling system doesn't seem to be working properly. Maybe that's why she is not starting when hot?
To delete a post see picture...!!!

Factory setting for Idle is turn clockwise until it stops then back out counter-clockwise 22 clicks or 1800 RPMs standard speed...

If it not starting hot,

Check your valve clearance for being too close preventing the valve to completely close..!!!

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.) for best performance around 0..21mm...
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.) for best performance around 0.14mm
 

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Also, I'm not following you:

"OEM ECU you can't touch the throttle once the key is turned ON & motor is running...will cause the TPS to be out of range, FI error & force into limp mode will not run/start...!!!"

I'm obviously missing something..., but if the motor is on and running, that means the key position is also on - how would someone be able to drive the bike without using the throttle?
The TPS has to be in range when the key is turned ON until the motor is running...see pictures
 

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Discussion Starter · #11 ·
The TPS has to be in range when the key is turned ON until the motor is running...see pictures
Thank you! My adaptor arrived today. Going to check the voltage tonight if I have time.

Update on the bike: Since changing the fuel filter, and putting an air filter on (I know this may not matter as much), I can finally get her cold started. She idles decently, but gets hot quickly. Going to check the cooling system in addition to your advisement above.
 

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Thank you! My adaptor arrived today. Going to check the voltage tonight if I have time.

Update on the bike: Since changing the fuel filter, and putting an air filter on (I know this may not matter as much), I can finally get her cold started. She idles decently, but gets hot quickly. Going to check the cooling system in addition to your advisement above.
Check your radiator level & make sure it's circulating...there may have air bubbles in the cooling system & needs them air burp out...

Too burp, open the radiator cap, take pliers & squeeze the lower cooling hose while the motor is idling...

Also Does your motor oil look normal or a milky color...???
 

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Discussion Starter · #13 · (Edited)
If I'm sitting on the bike, right side of the radiator get hot, left side doesn't.

Engine oil is milky. Don't tell me that coolant getting mixed in, cause we know what that means...😆

So, I just did some reading, as my TPS adaptor arrived yesterday and I'm getting ready to inspect the voltage. If I understand correctly, there is no option to adjust the voltage, correct? Sounds like if the TPS is out of range, I have to check the sensor resistance. If the resistance is ok, but bike is having the same issue, replace the ECU. If the resistance is NOT ok, I have to replace the throttle body assembly. Is this accurate?

Update Getting to know the bikes behavior a little better. Everyday I start her up once. The first start, she fires right up. I dont run her too long, because it seems to get hot, quick. I shut it down after about 2 minutes. The next attempt to fire it up, and all attempts after, require me to give it a little throttle for about 10-15 seconds, and it will stay idling. If I don't give it a little throttle, it won't start.
 

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If I'm sitting on the bike, right side of the radiator get hot, left side doesn't.

Engine oil is milky. Don't tell me that coolant getting mixed in, cause we know what that means...😆

So, I just did some reading, as my TPS adaptor arrived yesterday and I'm getting ready to inspect the voltage. If I understand correctly, there is no option to adjust the voltage, correct? Sounds like if the TPS is out of range, I have to check the sensor resistance. If the resistance is ok, but bike is having the same issue, replace the ECU. If the resistance is NOT ok, I have to replace the throttle body assembly. Is this accurate?

Update Getting to know the bikes behavior a little better. Everyday I start her up once. The first start, she fires right up. I dont run her too long, because it seems to get hot, quick. I shut it down after about 2 minutes. The next attempt to fire it up, and all attempts after, require me to give it a little throttle for about 10-15 seconds, and it will stay idling. If I don't give it a little throttle, it won't start.
(your quote)
Engine oil is milky. Don't tell me that coolant getting mixed in, cause we know what that means...😆

Yea! I was suspecting you have a blown head gasket causing low compression & your water temp sensor sending the ECU faulty readings ... You'll need to smell the exhaust for coolant & look for white smoke

Bad head gasket symptoms
  • White smoke coming from the tailpipe.
  • BUBBLING IN THE RADIATOR AND COOLANT RESERVOIR.
  • unexplained coolant loss with no leaks.
  • Milky white coloration in the oil.
  • Engine overheating.
 

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I think I got my work cut out for me. Drained the oil and it looks like there could be coolant in it. Also, drain plug has this milky substance on it. Almost looks like lube of some sort. Weird.
View attachment 29429
View attachment 29427
View attachment 29428
The drain plug is not OEM & is for stripped threads & has silicon on it to prevent leaking...

Sparkplug looks fine a running a little rich A/F mixture...But doesn't show coolant in the combustion chamber...It would be white not carbon black...! See picture of a coolant fouled below...

Oil & coolant will separate like water bubbles on oil do you see the separation in your oil...??? If not your fine put it back in...!

You'll need to check the compression 49~82 psi useable...

You need to check or replace your water temp sensor...

Here's the service manual
 

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Discussion Starter · #20 ·
Thanks DD. I noticed that the actual drain plug was stuck to the bigger plug too. It should have screwed off that the copper gasket. Why do you think that bigger bolt was install? You think maybe the previous owner put a hole in the oil pan while riding it, and didn't want to spend the money on a new pan - so then he just made a bigger hole, threaded it, and put that in? That's the only thing I can think of.

I will check the water temp sensor next.
 
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