Page 1 of 2 1 2 LastLast
Results 1 to 15 of 19

Thread: Thermostat hunting, 2014 GS

  1. #1
    On the Road
    Join Date
    Oct 2010
    Location
    Mount Vernon, WA
    Posts
    29

    Thermostat hunting, 2014 GS

    While test riding a new GS the temperature read out held steady in the 185 range. On my bike from day one is seems the thermostat hunts, just over shoots in both directions and never settles down. The digital read out varies from 180 to 192 and back to about 180 over a 15 second cycle. Does it constantly. (trouble with having too much information probably) How does your read out behave? I'm thinking a simple thermostat change out is in order to settle things down. Thanks.

  2. #2
    Cam Killer marchyman's Avatar
    Join Date
    Jun 2008
    Location
    SF Bay Area
    Posts
    3,633
    Normal AFAIK. Most of the time it cycles between two values. The limit values seem to vary with humidity and ambient temperature. Once in a great while the readout will sit at one value for some time. Don't know why. Also, on my bike the fan comes on when the thermostat hits 212. That seems to be +/- a few degrees of when others report their fan starts.

  3. #3
    Registered User
    Join Date
    Apr 2006
    Posts
    59
    beecher
    You're not alone
    Took my 2013 GSW out for a run today. It has about 7200 miles. I noticed the Engine Temp fluctuating between 176 and 192 then back. Mostly between 180 and 188. Up and down. Now, when newer it would hold very steady at around 178 and only go up to 182 under heavy load or speed. it did run around 185 when the ambient was over 100 degrees. I have a concern that something is not right--thermostat, or water level or a leak is the water system. Will check more tomorrow.

    Checked my fluid levels this AM. Oil above mid level, coolant between the marks. Conclusions is that the thermostat has started to fail. None of my autos display this hunting problem.
    Last edited by rgmanley; 12-08-2013 at 09:04 PM.

  4. #4
    On the Road
    Join Date
    Oct 2010
    Location
    Mount Vernon, WA
    Posts
    29
    Well, I'm not confident with the thermostat function. But I do have to say, a digital temp read out causes trouble on a small volume system. Too easy to see a change. Maybe a bar graph would not show this rapid variation. I suspect the fix will be software to dampen/average the read out. I have a PUMA going on it.

  5. #5
    Registered User
    Join Date
    Sep 2007
    Location
    So. Calif.
    Posts
    293
    Sorry, but what's a PUMA?
    '14 R1200GS,
    Priors: '13 K1600GT, '08 R1200RT, '04 R1150RT, '05 R1200GS, '73 R75/5.

  6. #6
    Registered User
    Join Date
    Apr 2006
    Posts
    59
    Quote Originally Posted by beecher View Post
    Well, I'm not confident with the thermostat function. But I do have to say, a digital temp read out causes trouble on a small volume system. Too easy to see a change. Maybe a bar graph would not show this rapid variation. I suspect the fix will be software to dampen/average the read out. I have a PUMA going on it.
    Agree, but consider that all the gauges in a vehicle are analog (voltage) that are then converted to a digital representation. When it starts to go up and down and up and down like ours are, which is a new behavior, something is amiss. Typically a thermostat that has trouble opening causes this yo-yo effect.

  7. #7
    Small road corner junkie pffog's Avatar
    Join Date
    Apr 2006
    Location
    WNY, Further fron NYC, than 6 entire states!
    Posts
    2,177
    Thermostat technology is, well ancient, and dates back to the early 1900's. Most modern temperature gauges are buffered, so not to "alarm" the operator. And any one who drove a vehicle back in the 70's knew gauges were worthless, as the first indication of overheating was steam from the hood, not the gauge. Fluctuation is NORMAL.
    2010 F800GS Full Ohlins package, '04 R1100S Replika
    '01 F650GS Wife's bike
    Maritime Alps and Vosges 2012
    Tuscany and Central Italy 2010

  8. #8
    On the Road
    Join Date
    Oct 2010
    Location
    Mount Vernon, WA
    Posts
    29
    Quote Originally Posted by sailorlite View Post
    Sorry, but what's a PUMA?
    It is where the dealer has no clue and officially asks BMW what the heck?
    Personally, I think it is a bad thermostat that is sticking. The dealer did not want to jump in with out feed back from the Fatherland, saying it could be a sensor. I doubt it. The dealer is a brand new one and just beginning to work on beemers. If the dealer will not address it, I'll put a new unit in myself.

  9. #9
    Registered User
    Join Date
    Sep 2008
    Location
    Wilmington, NC
    Posts
    2,145
    You don't know anything about the specifics of the gauge buffering and think its a bad thermostat You're probably not right. There are a bunch of things that can cause those trivial fluctuations you're talking about and they range from inherent in design to bubbles trapped to the location of the immediate opening in relation to flow and sensor position, and a few other things.

    The best case would be this is really an accurate system with a fast response and its showing you real data (not many temp gages are worth anything these days- see below) The worst is its showing you some minor variations for a reason you never find. Sometimes thermostats flutter a bit- whether that's a problem is mostly in the mind of the beholder as long as averages hang at or near the design point.

    I guess even a BMW thermostat is cheap enough to replace if you want to but doing that without understanding a real cause is unlikely to provide a result you'll like.

    As was said, modern oem gauges in cages are designed not to move and have hugely non-linear response curves built in- they are worthless as true temp gauges so if they make you happy, fine, but only a fool would take their cage temp readings as real and accurate. (Most gauges show the same temp over a 30-40 degree range these days- if you doubt that rig a removed one in a heated bath and see for yourself).
    There are good aftermarket ones both made for racers and enthusiasts and some of those are very good- they're also way too expensive to ever be oem.

  10. #10
    Registered User lkchris's Avatar
    Join Date
    Mar 2003
    Location
    Albuquerque, NM
    Posts
    5,187
    Regarding thermostats, here's an interesting quote from the BMW car club tech editor regarding lack of temperature gauge on recent models:

    Engine coolant temperature is now regulated electronically, varying widely over a broad scale depending on driving conditions and service demands. BMW and other car manufacturers use engine coolant temperature to tweak emissions and fuel economy ... . Coolant temperatures range from "quite high" at steady highway speeds to "sort of reasonable" during stop and go driving.

    Recent models that have engine coolant temperature gauges electronically buffer those gauges via the DME so that they read right in the middle unless broad parameters are exceeded in either direction ... .
    Kent Christensen
    21482
    '12 R1200RT, '02 R1100S, '84 R80G/S

  11. #11
    On the Road
    Join Date
    Oct 2010
    Location
    Mount Vernon, WA
    Posts
    29
    Quote Originally Posted by racer7 View Post
    You don't know anything
    Thanks for the input. It is interesting that individual bikes read out so differently. I'll keep you posted as to the end point.

  12. #12
    Registered User Paladinwest's Avatar
    Join Date
    Jun 2010
    Location
    BC South Central Interior
    Posts
    125
    Quote Originally Posted by beecher View Post
    The dealer is a brand new one and just beginning to work on beemers.
    Who is the dealer, I only know of the two in the Seattle area?
    2014 R1200GSA 33, 2008 HP2 Sport 10,000, 2008 R1200GSA 100,000 (Sold), 1990 R100GSPD 100,000, 1986 K100RS 152,000

  13. #13
    On the Road
    Join Date
    Oct 2010
    Location
    Mount Vernon, WA
    Posts
    29
    Ferndale Washington, just north of Bellingham now has a mixed brand dealer who carries BMW. He is close so I went there for the "get on the books" 600 mile check up.

  14. #14
    Still plays with trains. tinytrains's Avatar
    Join Date
    Oct 2009
    Location
    Torrance CA
    Posts
    562
    Yes, car gauges are buffered. When I plugged my ODB reader into my Mazda 3, I discovered the needle goes to center when the temperature reaches about 120 F and does not move after that. I assume it goes up somewhere around 220F. I thought it did a great job of regulating, but it turns out the gauge is just an idiot light with a needle.
    1988 K75 Low Seat
    2009 R1200R Roadster

  15. #15
    rabid reader dbrick's Avatar
    Join Date
    Apr 2003
    Location
    Santa Cruz CA
    Posts
    1,883
    Quote Originally Posted by tinytrains View Post
    Yes, car gauges are buffered.
    Been true for years. My son's 1988 Volvo 245 did that...until I bypassed the temperature compensating board in the instrument cluster.
    David Brick
    Santa Cruz CA
    2007 R1200R

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •