FYI, just had my '98 out in 46 F ambient temps for a spirited backwoods ride and coolant temp was consistently in the 165-168 range, despite the fact that the thermostat is new, and that the manual specs the thermostat opening temp as 173 or 176 F or so. In other words, theoretically, the coolant temp shouldn't ever be below the minimum opening temp of the thermostat, but, practially, that is what happens.
Take-away point? If your warmup time to operating temperature is "normal" (should be 3-5 miles if it's cold out), then operating at a temp in the mid-high 160s when it's cold outside is "normal."
Also, re: volts, mine usually pumps out 13.94 at 5k once all warmed up. I noticed today when starting out that it was putting out only 13.86 until it got warm. Check output voltage at normal operating temp if you want an accurate reading, would be my guess.
I was seeing mid 160's this morning at about 50 degrees F. It was a lower temp than I expected, but the thermostat "only" has about 6000 miles on it. Could just the (cold) airflow over the engine and the temp sensor is in the front (I think) head cause the temps to be low? I guess I'm wondering if the temp at the thermostat is actually, say, 175 but the sensor is only registering mid 160's because of placement.
Last winter I happened to check the operating temp on my way home from work one morning. I'd been at freeway speed for about 25 minutes. Air temp was showing 0 degrees Celcius, engine temp was 70 degrees celcius.
As a comparison, yesterday afternoon I checked again. Air temp was 40 degrees Celcius, (it's summer here) engine temp was 88 degrees Celcius. After being stopped at a traffic light for about 10 seconds the engine temp started rising pretty quickly, it was at 96 degrees by the time I got home.
thereisnospoon, Jan 21 2007, 02:52 PMI guess I'm wondering if the temp at the thermostat is actually, say, 175 but the sensor is only registering mid 160's because of placement.
I'm thinking that must be what is happening. I know my ZRX has the temp sensor right at the thermostat and it runs 175-180 in this weather, but offhand I've forgotten where the VFR's temp sensor is located.
thereisnospoon, Jan 21 2007, 02:52 PMI guess I'm wondering if the temp at the thermostat is actually, say, 175 but the sensor is only registering mid 160's because of placement.
I'm thinking that must be what is happening. I know my ZRX has the temp sensor right at the thermostat and it runs 175-180 in this weather, but offhand I've forgotten where the VFR's temp sensor is located.
Well I looked in the book and it is the "ETC/Thermosensor" that is in the inside of the front head... right next to the water outlet headed to the thermostat. So... I dunno now. I guess one of those cool laser thermometers might be handy... it would be nice to have a second opinion on what the water temp actually is, just out of curiosity. My truck will eventually get to 195-198 (by the computer) between 8 and 90 degrees F while the bike fluctuates based on ambient temp, guess I'm just not used to it.
thereisnospoon, Jan 21 2007, 02:52 PMI guess I'm wondering if the temp at the thermostat is actually, say, 175 but the sensor is only registering mid 160's because of placement.
I'm thinking that must be what is happening. I know my ZRX has the temp sensor right at the thermostat and it runs 175-180 in this weather, but offhand I've forgotten where the VFR's temp sensor is located.
Well I looked in the book and it is the "ETC/Thermosensor" that is in the inside of the front head... right next to the water outlet headed to the thermostat. So... I dunno now. I guess one of those cool laser thermometers might be handy... it would be nice to have a second opinion on what the water temp actually is, just out of curiosity. My truck will eventually get to 195-198 (by the computer) between 8 and 90 degrees F while the bike fluctuates based on ambient temp, guess I'm just not used to it.
I'm guessing, but the ETC/Thermo thing might not be coolant temp, but engine or sensed ambient air temp used to regulate the FI's rich/lean mix. Lots of sensors on this baby, including one that sends ambient air temp to the dash panel - different from the one that tells the ECU how cold it is out?? Same? Don't know. Just know I've done everything I can, and everything's done right, and it runs at 166-68 at 46 degrees. I'm buttoning it up and calling it good.
What is, exactly, the complaint/problem? Are you concerned that your thermostat is programmed to open at a temperature higher than that which the fluids actually have when the weather is cold enough to keep them below that threshold? You shouldn't. If I'm not mistaken (disclaimer clause there), if your coolant is below the temp. at which the thermostat opens, then it's because it's not necessary. It's already cool enough due to the effect the ambient temperature has over it. Unless of course, you've managed to reprogram the thermostat's required temp for opening.
Or are you just wondering whether your coolant temp. readings are really accurate from a practical point of view??
I ask because in your first post you say (and I quote): theoretically, the coolant temp shouldn't ever be below the minimum opening temp of the thermostat, but, practially, that is what happens.
Sorry to say but "theoretically" it should, can and will be below the thermostat's minimum opening temp.depending on the time of year / ambient conditions. It happens and is meant to. The thermostat's opening threshold temp. is what it is because scientists have decided that from that temp upwards, nature can no longer do the trick and requires help from human ingenuity!! So take it easy dude, NO WUCKIN' FURRIES!!
(The author claims no responsibility for costly repairs incurred as result of one not doing their own homework!!) HAHAHAHAHAHA blink.gif
My guess is that coolant temp sensors are not all that accurate and a 4 or 5 degree F variation from bike to bike is not abnormal. I also think the temp readout is affected by the condition of the electical system.
Auspa�ol, Jan 23 2007, 05:49 AMWhat is, exactly, the complaint/problem? Are you concerned that your thermostat is programmed to open at a temperature higher than that which the fluids actually have when the weather is cold enough to keep them below that threshold? You shouldn't. If I'm not mistaken (disclaimer clause there), if your coolant is below the temp. at which the thermostat opens, then it's because it's not necessary. It's already cool enough due to the effect the ambient temperature has over it. Unless of course, you've managed to reprogram the thermostat's required temp for opening.
Or are you just wondering whether your coolant temp. readings are really accurate from a practical point of view??
I ask because in your first post you say (and I quote): theoretically, the coolant temp shouldn't ever be below the minimum opening temp of the thermostat, but, practially, that is what happens.
Sorry to say but "theoretically" it should, can and will be below the thermostat's minimum opening temp.depending on the time of year / ambient conditions. It happens and is meant to. The thermostat's opening threshold temp. is what it is because scientists have decided that from that temp upwards, nature can no longer do the trick and requires help from human ingenuity!! So take it easy dude, NO WUCKIN' FURRIES!!
(The author claims no responsibility for costly repairs incurred as result of one not doing their own homework!!) HAHAHAHAHAHA blink.gif
My post was intended to be informative, not an inquiry. There are many on here (myself among them) who replace their thermostats because the conclude they're stuck open when they run the bike below the thermostat's stated opening point. By posting here, I was giving those folks the benefit of my recent experience in order that it might save some unnecessary thermostat replacements. As part of the exchange with responders, I necessarily gave my own bike's current/past status, as well as my own thoughts as to causation, etc. Thanks for yours.
Now I see where you were heading. blink.gif That is a good question though; what negative repercussions would a thermostat that's stuck open have? Not as bad a being stuck closed that's a dead certainty.
Sorry if it looked like I was being condenscending, that was not my intention. fing02.gif Funnily I've never had problems with thermostats on bikes, but an old '71 Ford Fairlane gave me my fair share of grief.
Auspa�ol, Jan 23 2007, 09:10 AMwhat negative repercussions would a thermostat that's stuck open have?
Fuel injected bikes use coolant temp as an input to regulate fuel input to the motor. When the coolant is cold, the ECU assumes the bike has just been started and combines the "0" coolant temp with the outside air temp and feeds an appropriate amount (more) of fuel to start and run the bike in that condition. The amount fed changes as the motor warms to maintain driveability and emissions, depending on, among other things, coolant temp. A partially stuck-open thermostat that doesn't allow the coolant to get hot enough to signal the ECU to cut back on fuel "could" cause the bike to run rich, perhaps to the point allowing unburned fuel to run down the cylinder walls, removing the oil and diluting the crankcase oil. That would be a worst case scenario, while lesser issues could include problems with driveability due to richness.
My highly unscientific observations indicate my bike runs approximately 100F over ambient when at steady state cruise (like that happens very often). But being in the south, I rarely ride when it's really cold. YMMV
Unfortunately mine's in Celsius but I can vouch for it reaching 100-103�C when traffic is bad or stopped at a bad run of red lights. I'll have to verify it, but believe it gets down to the high-50s / mid-60s when the weather is cold. It doesn't generally get all that cold around here but we're currently in a sudden-drop cold spell. My concern is more whether the upper temps are too high (Summers are scorchers here).
Another curiosity...As it's "cold" here at the moment, I find myself needing the choke to get her to turn over. The bike that is!! The '98 fifth gen still had the manual choke control. Does that mean my silver viffer is under the influence of both systems and, as such, on overkill? Like any motor with the choke on, it runs rough if you place it under labour by engaging the gears, especially if you wish to throttle it somewhat. Thing is, my bike takes a while to warm up, (it was the whole contemplating what the negative consequences might be from the dilemna presented in this thread which has me putting this forward), quite a while, and the thinking here in Spain is that it's better not to wait long and set off at low speed, low gear, low revs, to at least supply lubricant, cold as it may be, to the necessary parts of the motor. My initiation into motorcycling did not take place here in Spain and I was more of the tendency to let a motor warm up a little before selecting gear and taking off.
With the VFR (mine that is) if I don't leave the choke on (at the minimum required to keep it idling at 1000-1100 rpm), it conks it (snuffs it) between gear changes on engaging the clutch or selecting neutral at lights. What is the collective's opinion as to this practice. Should I desist and hold my horses? I defer to the great pool of wisdom latently lurking in VFRD's memory banks...
End of thread · 13 posts recoveredWayback Machine snapshot 2 Mar 2007