Heat Guage - Kawasaki KLR 650 Forum
1987 to 2007 Wrenching & Mods For maintaining, repair or modifications of Generation 1 KLR's. 2007 and earlier.

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 13 Old 08-15-2014, 01:09 PM Thread Starter
Neutral
 
Join Date: Aug 2014
Location: Williamsburg, Va
Posts: 14
Heat Guage

I've put about 200 miles on my new to me 06 klr. Going down the road the Engine Temp needle hangs out smack in the middle of the gauge. My one concern is when I shut off the engine (idling just long enough to get my feet planted) and the key is still in the ON position the needle spikes into the danger zone. Usually the fan revs up and I leave the electricity on until it disengages but is this normal with the KLR or should I be concerned about cooling?

Last edited by ChutingVa; 08-15-2014 at 01:45 PM.
ChutingVa is offline  
Sponsored Links
Advertisement
 
post #2 of 13 Old 08-15-2014, 09:03 PM
Threadjacker
 
Lockjaw's Avatar
 
Join Date: Jul 2008
Location: Benicia, CA
Posts: 6,750
Quote:
Originally Posted by ChutingVa View Post
idling just long enough to get my feet planted)
It is quite possible that I am just exhausted, but I don't understand what this means. The thermostat on your KLR should, in theory, be in the middle like a car. Stock, most KLRs spend their lives with a needle that never moves unless it is really hot or you are sitting still. You can modify it so that the fan kicks on at a lower temp, but your questions begs several Qs.

Stock, I've only ever heard of people being weirded out because the needle rarely moves. If I get you right, engine off and electrics on, then yeah, it makes sense that you would see the temp gauge rise. But I would be wary of a stock bike that has a normal riding temp that puts the gauge in the center.

Sorry, that reads like I'm drunk, but you get the idea, I hope.




"In a car you're always in a compartment, and because you're used to it you don't realize that through that car window everything you see is just more TV." R. Pirsig

PPMC #1.
Soon, we ride.

AKA JD Mader or you can call me "Dan" just not early for dinner.

Click my handle for a link to my homepage/blog...which has nothing to do with MCs. Free literature and music! Viva La Revolucion!
-------------------
2008 KLR 650
RIP DM - Soon, we ride.
Lockjaw is offline  
post #3 of 13 Old 08-15-2014, 09:43 PM
5th Gear
 
Join Date: Jan 2011
Posts: 4,710
My diagnosis, no problem!

Ignition switch off, no power to temperature gauge; power ALWAYS to fan circuit.

You kill the engine, hot coolant flows by convection, not water pump circulation, to the thermal switch at the bottom of the radiator; fan kicks in 'til coolant stabilizes at equilibrium.

Can't explain spike on temperature gauge (since sensor and meter are unpowered when ignition switch is OFF; transient capacitor discharge?
)
Whatever, don't think engine is cooking itself.

CAVEAT: Did not check wiring diagram; using flawed and perhaps erroneous memory, vis-a-vis Generation 1 circuitry; corrections and clarifications welcomed.
Damocles is offline  
 
post #4 of 13 Old 08-15-2014, 11:18 PM
Lifetime Member
 
650Stew's Avatar
 
Join Date: Jun 2010
Location: Alberta, Canada
Posts: 2,480
My bikes all get hotter after you shut them off, I always just attributed it to the water pump not circulating the coolant anymore even though the cylinder is still plenty hot.

That being said, my Gen 2 runs in the lower quarter of the gauge most of the time where'as you say yours usually runs in the middle? Just curious, does your bike have a thermobob installed? That would put your temp in the middle right off the bat.

As was already said though, no harm to your bike is occurring, sound's like normal operation to me. At work I run a diesel 6 wheeled Gator quite a bit and the fan quite often kicks in after I shut it off (the fan circuit on the Gator runs regardless of the ignition switch).

650Stew is offline  
post #5 of 13 Old 08-16-2014, 12:45 AM
Threadjacker
 
Lockjaw's Avatar
 
Join Date: Jul 2008
Location: Benicia, CA
Posts: 6,750
Quote:
Originally Posted by 650Stew View Post
That being said, my Gen 2 runs in the lower quarter of the gauge most of the time where'as you say yours usually runs in the middle? Just curious, does your bike have a thermobob installed? That would put your temp in the middle right off the bat.
That's my question, too. Never heard of a stock bike running in the middle.




"In a car you're always in a compartment, and because you're used to it you don't realize that through that car window everything you see is just more TV." R. Pirsig

PPMC #1.
Soon, we ride.

AKA JD Mader or you can call me "Dan" just not early for dinner.

Click my handle for a link to my homepage/blog...which has nothing to do with MCs. Free literature and music! Viva La Revolucion!
-------------------
2008 KLR 650
RIP DM - Soon, we ride.
Lockjaw is offline  
post #6 of 13 Old 08-16-2014, 11:51 AM
4th Gear
 
Join Date: Oct 2013
Location: Chilliwack, BC, Canada
Posts: 1,481
Stored heat in the cylinder head and exhaust heat the coolant in the head to a higher than normal temperature when engine is stopped and allowed to sit. This when temperatures are higher and/or when the engine has had other opportunity to build up heat, such as low speeds which deprive the engine of the very significant amount of direct "cooling fin" cooling by air flow.

Sounds normal in that regards.

If you have a Thermo-Bob, Thermo-Bob2, or other by-pass system a higher temperature thermostat is able to be tolerated which will raise the gauge indicator and maintain the indicator needle's position within a much narrower range. I see that on every bike using a by-pass system as one would expect.

Would you please clarify what you mean by, "the needle spikes into the danger zone."?

Do you mean that the needle is moving into the red area? Not trying to be nit picky, just wanting to insure that I'm understanding your concerns as don't want to provide bad information.

You can check the needle position compared to specified sensor temperature to determine whether your gauge might be indicating higher than real temperatures. I'll have to dig out my notes but have posted resistance versus temperature figures for the sender and can post an overlay which shows temperature in degrees for the gauge.

If you have an interest, Wattman's temperature gauge overlay is great fun to have if one likes numbers. I made one but IMO it's not anything like worth the trouble in making one.

Bike makers seem to have decided that temperature numbers on gauges aren't a good idea and I agree. People don't understand what they are reading and go in all directions.

Post back if you can't find the temperature sender numbers and I can post again.

HIH

Norm
Normk is offline  
post #7 of 13 Old 08-16-2014, 12:56 PM
5th Gear
 
Join Date: Jan 2011
Posts: 4,710
A transient spike from the temperature gauge would more likely be electrical, rather than thermal, in nature, IMHO.

Just completed a 2000-mile ride on a Versys, a Kawasaki 650 cc motorcycle, but with about twice the power of a KLR650. Kawasaki got smart; no temperature gauge on the Versys, only a dashboard warning (not unlike an "idiot light") of overheating. No radiator bypass either, AFAIK.

Unprovable theory: Fewer Themo-Bobs would have been produced, had KLR650s similarly been equipped with idiot lights, vs. temperature gauges.

Last edited by Damocles; 08-16-2014 at 12:59 PM.
Damocles is offline  
post #8 of 13 Old 08-16-2014, 01:38 PM
2nd Gear
 
Join Date: Apr 2013
Location: Woodridge, IL
Posts: 120
You don't have to leave the electrics on, the fan on a gen1 will run without the key if it damn well pleases.
kyxon is offline  
post #9 of 13 Old 08-16-2014, 01:41 PM
4th Gear
 
Join Date: Oct 2013
Location: Chilliwack, BC, Canada
Posts: 1,481
Conjecture either way regarding a transient spike of the temperature gauge. Thermostats can stick slightly which resolves and doesn't reoccur.

As for the lack of by-pass on the Versys, my friend Fast Eddie Copeman has #1 & #2 (sold to the public) ThermoBob kits on his two Versys. The desirability of a by-pass system is distinct from the excursions which may be seen on the temperature gauge. My point was similar to yours, I think, in that the gauge does tend to encourage speculation on the part of the uninformed.

On the other side of that coin, the binary aspect of warning lights means that a trend towards a problem is not anticipated and the degree (literally in this case) of the problem cannot be examined from the bike's instruments. I'm a fan of temperature gauges but do accept that putting numbers onto them is generally counter productive for makers.

A by-pass system is almost universal on automotive and larger applications, as well as higher end bikes. I'm completely adrift to understand why Kawi would knuckle under for the modest cost of a pair of drilled holes and a hose. Clearly, by-pass and higher temperature thermostat is the superior strategy.

If someone is motivated to install a T-bob out of movement of the temperature gauge alone, that is limited justification but still does achieve the same advantages.

Running the engine under cold conditions is not conducive to efficiency or longer engine life. The KLR engine sees a huge difference in temperature between top and bottom of cylinder as well as a reported 40 F difference between the temperatures at the temperature sender and the thermostat. Anyone who has studied the coolant passages has almost certainly felt the same shock over the last difference as have I.

The engine was clearly designed to operate at above 210 F. One can easily prove this by virtue that the fan switch operates at 210 F so the engine clearances had to be designed for that operating range. The temperature routinely goes much higher under hot and slow conditions with no harm so someone can speculate a number for the high temperature design limit. 235? 250? I don't know either but one doesn't have to even crack an engineering text to support the design temperature must by up there.

So, let's use 220 F as the number. Low but to illustrate: that is 60 F lower than the thermostat and almost certainly at least 100 F below the temperature of the bottom of the cylinder. Reports have shown the cylinder temperature can bridge 140 F from top to bottom and my primitive instruments seem only to support that.

Put a bore gauge into some KLR cylinders torqued to a head and watch what happens when the head is placed into near boiling water. Taper and out of round make excursions as one knows must happen.

A straw poll of T-bob users reported that oil consumption and fuel mileage improved with the install.

The misquoted: "If ignorance is bliss, 't'is folly to be wise." makes the point, IMO. People ignore the "If". It is seldom beneficial to be ignorant if one is able to act on the information., IME.

I think this illustrates that people often do the right thing for the wrong justification.

I'd put a by-pass system onto a Versys as the second modification, right after a better engine guard. Having done by-pass and higher temperature 'stat to something like a dozen KLR650's, am hoping to do a couple of KLX250's after the summer.



Quote:
Originally Posted by Damocles View Post
A transient spike from the temperature gauge would more likely be electrical, rather than thermal, in nature, IMHO.

Just completed a 2000-mile ride on a Versys, a Kawasaki 650 cc motorcycle, but with about twice the power of a KLR650. Kawasaki got smart; no temperature gauge on the Versys, only a dashboard warning (not unlike an "idiot light") of overheating. No radiator bypass either, AFAIK.

Unprovable theory: Fewer Themo-Bobs would have been produced, had KLR650s similarly been equipped with idiot lights, vs. temperature gauges.
Normk is offline  
post #10 of 13 Old 08-16-2014, 01:44 PM
4th Gear
 
Join Date: Oct 2013
Location: Chilliwack, BC, Canada
Posts: 1,481
Much like my wife moving furniture?

My Gen1 fan only operates with the key on as have modified the system. It was an experiment so I can listen for peculation, which so far has not been evident.



Quote:
Originally Posted by kyxon View Post
You don't have to leave the electrics on, the fan on a gen1 will run without the key if it damn well pleases.
Normk is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki KLR 650 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Heat grips MotoPhoto 1987 to 2007 Wrenching & Mods 3 12-09-2013 08:48 PM
Heat Help Please tat2matt 1987 to 2007 Wrenching & Mods 4 05-06-2010 08:14 PM
After Market guage cluster mods? Breck Gadgets & Gizmos 0 03-18-2010 09:37 AM
Heat Shield basement 2008+ KLR650 Wrenching & Mod Questions 16 12-11-2009 10:59 PM
Temperature Guage Failer jwoodj 2008+ KLR650 Wrenching & Mod Questions 2 07-24-2009 09:15 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome