FJR Owners Forum banner
  • Hey Everyone! Enter your bike HERE to be a part of this months Bike of the Month Challenge!
1 - 15 of 15 Posts

·
Registered
Joined
·
24 Posts
Discussion Starter · #1 ·
2012 FJR 1300 Gen II 26,000
New York City
Monthly commute: 1,000 miles

Idle problem has returned with the cold weather.
I have tried fuel stabilizer (SeaFoam). I've changed the spark plugs recently and done throttle body sync. Air filter is 6 months old. There are no cracks in the vacuum tubes. I removed the AIS system last year, which had some gunk in it and it helped a little. Idle is set to 1,100 RPM.
I believe the problem may be with the map sensor or throttle position sensor? What can I do about this? I've looked at the MAP sensor port without seeing anything remarkable.
The following problem only occurs when the temperature drops:
The bike immediately starts then quickly stalls. The 2nd start stays on, but runs roughly at 1100 RPM. After about 4 minutes as the engine warms, the rpm drops to ~500 and will stall; even if I'm riding. It will stay on if I am giving it gas. This problem persists for about 10 minutes. Then no problem. As the temperature continues to drop moving into winter, the problem will get worse. It is inconvenient having to continually hold the throttle.
HELP!
 

·
Premium Member
Versys 1000, VFR800
Joined
·
9,591 Posts
You may have your idle set too low, 500 rpm when warm??? Normally, cold start should result in idle of ~1500 or more, then when the coolant temperature comes up, warm coolant circulates into the wax mechanism, and idle will drop to what you have it set at warm.... yes, we all say 1100.

So, in your case, I interpret that your cold idle is 1100 and then drops to 500 when warm..... you need to bump that up, again, set it to 1100 when warm.
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #3 ·
You may have your idle set too low, 500 rpm when warm??? Normally, cold start should result in idle of ~1500 or more, then when the coolant temperature comes up, warm coolant circulates into the wax mechanism, and idle will drop to what you have it set at warm.... yes, we all say 1100.

So, in your case, I interpret that your cold idle is 1100 and then drops to 500 when warm..... you need to bump that up, again, set it to 1100 when warm.
I didn't specify. After I'm riding for 10 minutes, it returns to 1100 RPM.
So, at cold, from start, it's about 1500 RPM, then after a few minutes drops to 500 RPM, then returns to 1100 RPM after almost 10 minutes. I'll try increasing, but that last time I did, I felt like it was already cranked all the way.
 

·
Premium Member
Versys 1000, VFR800
Joined
·
9,591 Posts
At that mileage, I wouldn't expect the MAP sensor nipple/hose to be crudded up, but who knows. If you're out of adjustment, have you tried a throttle body sync? It can affect your range of adjustment, however, it sounds like you're in the ballpark.... you're just out of range for futher adjustment.....

So the question is what causes it to drop from 1100 to 500....... I would check the sync just to ensure all cylinders are equal. Are the spark plugs OK.... old plugs can perhaps "suck up" juice and not be firing at lower rpms while high speed may not be affected.

Another thing to try, is remove (unscrew and pull) the spark plug adapters off the spark plug wires, trim off 1/4", spread the strands evenly and re-install...... however, while you have them off, check the resistance of each adapter... if you've got a wildly different one, they can be taken apart, resistor cleaned up and reassembled.... recheck resistance.

Try that and report back.........

You titled the thread "annual......" do you have this problem every year?
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #6 ·
At that mileage, I wouldn't expect the MAP sensor nipple/hose to be crudded up, but who knows. If you're out of adjustment, have you tried a throttle body sync? It can affect your range of adjustment, however, it sounds like you're in the ballpark.... you're just out of range for futher adjustment.....

So the question is what causes it to drop from 1100 to 500....... I would check the sync just to ensure all cylinders are equal. Are the spark plugs OK.... old plugs can perhaps "suck up" juice and not be firing at lower rpms while high speed may not be affected.

Another thing to try, is remove (unscrew and pull) the spark plug adapters off the spark plug wires, trim off 1/4", spread the strands evenly and re-install...... however, while you have them off, check the resistance of each adapter... if you've got a wildly different one, they can be taken apart, resistor cleaned up and reassembled.... recheck resistance.

Try that and report back.........

You titled the thread "annual......" do you have this problem every year?
I recently performed a throttle body sync. One cylinder was slightly off.
Is there a way to add further adjustment to the idle? I want to check as mush as I can when I lift the tank up.
Spark plugs are 3 months old. Problem occurred last winter too with old spark plugs.
 

·
Premium Member
Versys 1000, VFR800
Joined
·
9,591 Posts
The coolant sensor is on the right end of the coolant tube on top of the engine. I don't recall anyone having a bad one. Resistance check is 290-354 ohms @ 80C/176F. Submerge in hot water.
If you are seeing normal coolant temps displayed and the fans come on at a normal temperature (7 bars on a Gen2) and not at a significantly lower temperature, then the sensor is likely OK.

If this is a cold weather only symptom, the Intake Air Temperature sensor in the air box will likely affect idle more, but those don't have many issues either. Resistance check is 290-390 ohms @ 80C/176F. Submerge in hot water.

02 sensor could also affect idle, you could try unplugging it as an experiment (connector on right end of throttle bodies).

MAP sensor is basically sensing altitude, but must be able to do so.... ensure vac line is clear.

Check other vac lines for leaks/cracks, expecially those little caps on the TB sync ports as Russ mentioned.
 

·
Registered
Joined
·
183 Posts
The Yamaha 600 cc sport bikes had cold start problems that were entirely resolved by further enriching the mixture by tuning adjustments. Trying to give it throttle on start would only make matters worse because it was adding air.
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #12 ·
SOLVED
Same problem and fix as last year. I lifted the tank, pulled the tubes from the MAP sensor. I blew through the tubes and I wouldn't say I felt any great resistance; regardless, I sprayed Gum Out, waited 5 minutes, sprayed Gum Out again. I held each of the openings to independently let the spray course through each tube pathway. I sprayed again with compressed air (Dust Off), then ran a wire through each section (no great amount of gunk or dirt). I reinstalled and the bike has worked great for a week. The job took less than an hour, including lifting the tank. It was counter-intuitive to think the tubes would be clogged after only about a year, but there you have it. Such a difference in performance, acceleration, etc.

Reference item numbers 10, 11, 12, 13 in the link below:
 

·
Premium Member
Versys 1000, VFR800
Joined
·
9,591 Posts
Excellent! The old MAP sensor problem........ sometimes that triggers an error code 14, did you find any stored codes in DiAG mode?
 

·
Registered
Joined
·
183 Posts
Had collapsing vac hoses on a different model bike. The hoses were fine by visual and tactile inspection. But swapping those hoses was the only thing that permanently resolved it. Heat softened them up apparently. The store handed me windshield washer fluid line; happened to notice the "1.0 bar" printed on the line. Took it back and got actual vacuum line from a different parts store. Can't go by wall thickness of the line.
 
1 - 15 of 15 Posts
Top