I know this has a thermostat but,
- Thread starter Semper Fi
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Help Support Yamaha FJR Motorcycle Forum:
Geezer
Parsimonious Curmudgeon
I use the voltage meter on my radar detector, so the number is not entirely accurate, but it drops a couple of tenths of a volt when the fan comes on, and continues to drop a tenth at a time if the fan runs for more than a few minutes while sitting in traffic. I normally open the throttle a bit to raise the RPMs if it drops below an indicated 12 volts to keep the voltage above 12. Normal operating voltage indicated is around 13.2 or 13.4.
I do not live in a high traffic area and I only have this problem when stuck in traffic for more than a few minutes at a time. It probably happens once or twice a year.
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Semper Fi
Well-known member
Thanks for all the help. You have made me believe that I should just ride and forget about the meter showing 3 bars.
SkooterG
Purveyor of Crooked Facts
As much as I hate to, I'm going with Iggy here. He has some experience in these matters. Farm animals too, but that is another matter.
Ride more, stress less.
Ride more, stress less.
escapefjrtist
Searching for Dry Roads
Start here ^^^^ first. My previous '06 began to run hotter than normal and a good radiator cleaning and gentle fin back flush fixed it right up. I've kept up on cleaning my current '09 and no issues...Douche the hell out of the radiator fins with a squirt bottle full of hydrogen peroxide. When you think it's saturated, douche it some more. Rinse them off with a water hose with gentle pressure. You'd be surprised at what thousands of dead bugs will do to your airflow.
Then go ride!
YMMV
--G
TomInPA
Well-known member
Your bike is not charging at an optimal rate, and it could be the battery, rectifier, or resistance in the harness. Before starting my bike shows 12.8-13.1 VDC. During operation without significant electrical loads, the bike will show 14.0 - 14.2 VDC. With the fan on, the voltage drops to 13.8, and I modulate the use of accessories to stay above 13.4 VDC at all times during operation. Like you, I use the X50 radar detector for a voltage meter, so I can only assume, you have other issues...
We all ride FJR's and post on a forum, I guess we all have other issues. I assume we have at least established the O.P. does not have a problem outside of worrying too much?
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Geezer
Parsimonious Curmudgeon
Thanks for your ideas. There are a lot of variables. In any case, it's been that way since new and I'm not changing anything now.
travelenfjr
Member
From my recent experience the thermostats do go bad. My 03 has been heating up for a couple of years. Finally ordered thermostat and when I took out the old one part of the internal spring was laying in the housing.
Installed new one and is like new. I also pulled radiator, cleaned and flushed exterior and interior. Put some paint on it looks good. You should also replace the O rings when changing the thermostat. Bought parts from CyclePartswarehouse.com.
Installed new one and is like new. I also pulled radiator, cleaned and flushed exterior and interior. Put some paint on it looks good. You should also replace the O rings when changing the thermostat. Bought parts from CyclePartswarehouse.com.
Several of you have suggested cleaning the bugs out of the radiator fins with a hose. I have done that and hopefully not damaged it by using a rather strong spray. Your comments seem to caution, use gentle flow?
bluesdog
Well-known member
Apply a liberal amount of hydrogen peroxide. Wait for 10 minutes or so. Apply another dose of hydrogen peroxide. Wait another 10 minutes. Rinse with a gentle stream of water.
Hydrogen peroxide is also the shazitz for dissolving dried bug remains from the rest of the bike
RossKean
Well-known member
Are you using full strength "drugstore" peroxide solution (i.e. 3%)? My Gen II is running a little hotter than normal this year and I suspect that airflow isn't what it used to be. Probably a combination of bugs and road tar. The peroxide should help with the bugs but I don't know what will help with the tar - maybe some engine degreaser. Anyone find anything that works for this? I know that something like Varsol will dissolve tar but I don't think I want to start soaking with solvents.
bluesdog
Well-known member
3% h202 doesn't seem to be necessary. I dilute to 50-50 with plain old water, in a spray bottle. It doesn't dissolve tar, unfortunately, but I use a good non-petro-based degreaser on painted surfaces, and found lighter fluid works well to dislodge tarry bits from difficult areas, such as the recesses atop the engine where the coolant pipes connect, (had to clean up that area when I did the valve check a while back)
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From Service Manual -- thermostat is closed below 71 degC. It's fully open at 85 degC.
Two bars on display -- 60 to 80 degC.
Three bars -- 80 to 100 degC.
Four bars -- 100 to 110 degC.
Fan comes on at 105 degC and stays on until temp drops below 100 degC (three bars).
On mine it's quite normal to see the display oscillating occasionally between two and three bars which means the operating temperature is +/- 80 degC.
You would have to be seeing a continuous three bars for the thermostat to be fully open.
Two bars on display -- 60 to 80 degC.
Three bars -- 80 to 100 degC.
Four bars -- 100 to 110 degC.
Fan comes on at 105 degC and stays on until temp drops below 100 degC (three bars).
On mine it's quite normal to see the display oscillating occasionally between two and three bars which means the operating temperature is +/- 80 degC.
You would have to be seeing a continuous three bars for the thermostat to be fully open.
bergmen
Well-known member
Be careful with hydrogen peroxide as it is a very strong oxidizer and will cause corrosion if it is not completely rinsed off. I would be very careful as to what is exposed and don't overdo it.Douche the hell out of the radiator fins with a squirt bottle full of hydrogen peroxide. When you think it's saturated, douche it some more. Rinse them off with a water hose with gentle pressure. You'd be surprised at what thousands of dead bugs will do to your airflow. Then go ride!
Dan
This ^^^
N.B. we are talking 1st gen FJR 'bars" here.
When you are stopped, in stop and go traffic, or even when following behind traffic that messes up the air flow, to your radiator like following a truck, you can expect the temp to run up to ~105 C before the fan even comes on. That would be 4 bars on a 1st gen temp gauge.
If your coolant isn't puking on the ground I wouldn't worry about the engine overheating
The Gen I radiator fan is fused at 15 amps. I'd speculate that the actual running current is approximately 6 amps or so.
I have a gripe with the FJR designers about the operation of the radiator fan. On those infrequent occasions when I've synced the throttle valves I've seen four bars on the display and the fan came on as expected.
I'll run the engine long enough for the fan to cycle off and then shut down the engine for a throttle valve adjustment. While shut down the temp will creep back up enough to trigger on the fan.
The fan comes on when I switch on the ignition. Then I'm forced to wait a while for cool down or crank the engine with the fan running which I don't want to do.
I wish the designers had blocked the fan's operation during engine cranking. Shut off all unnecessary loads controlled by relays while cranking the engine. Once it's started then bring those loads online as necessary.
When the engine is off and the ignition is switched on I don't see much value in running the radiator fan particularly when you're cranking to restart.
I have a gripe with the FJR designers about the operation of the radiator fan. On those infrequent occasions when I've synced the throttle valves I've seen four bars on the display and the fan came on as expected.
I'll run the engine long enough for the fan to cycle off and then shut down the engine for a throttle valve adjustment. While shut down the temp will creep back up enough to trigger on the fan.
The fan comes on when I switch on the ignition. Then I'm forced to wait a while for cool down or crank the engine with the fan running which I don't want to do.
I wish the designers had blocked the fan's operation during engine cranking. Shut off all unnecessary loads controlled by relays while cranking the engine. Once it's started then bring those loads online as necessary.
When the engine is off and the ignition is switched on I don't see much value in running the radiator fan particularly when you're cranking to restart.
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