Cool oil

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    • #11707
      David Lord
      Participant

      A quick 20 mile dash on the Trident this afternoon (because I felt the urge!). Ambient temperature was 8 degC and the oil never got above 50deg and it took all of the ride to get that far.

      20201106_133314

    • #11708
      richard beard
      Participant

      A good case for fitting an oil thermostat IMHO.

    • #11709
      David Lord
      Participant

      Ah, but where Richard?  There is no oil cooler on this bike!

      David

    • #11710
      richard beard
      Participant

      So–no oil thermostat on your bike then, David.

      However most triples have an oil cooler fitted and instead of 50C that you attained their maximum temperature would have been less than 50C–all other things being equal.

      IMHO if you have an oil cooler fitted (as most triples do) then it is a good idea to fit an oil thermostat.

      Just my two cents worth of course.

    • #11711
      michael roberts
      Participant

      Hi Richard,

      I’m in the process of building a Rickman framed T150. I’d value your opinion on whether I’m going to need an oil cooler, given that the Rickman has oil in the frame, although less than the 6 pints in the original tank. I’m in the south of the UK.

      TIA,  Mike

    • #11712
      David Lord
      Participant

      Michael, notwithstanding anything Richard might add, it may be helpful for you to know why it works well without a cooler on my bike :  The oil tank capacity is 5 litres and the oil tank is a big “box” across the width of the bike so there is a lot of surface area exposed to air flow.  A high flow oil pump is fitted and I’m running 20w50 synthetic oil.  I can monitor oil temp in the tank and on a hot English summer day it can reach 80 deg C, which is no problem for synthetic oil. The cooler was only left off because without the full race fairing intended for the P&M frame there is nowhere sensible or convenient to mount a cooler.

    • #11714
      richard beard
      Participant

      Hi Mike,

      The original spec for the cooler was to maintain a maximum oil temperature of 85C under conditions of an ambient temperature of 52C using WOT (wide open throttle) to thermal equilibrium (which we reckoned to take 10-15 minutes).

      So under the vast majority of operating conditions the cooler overcools the oil.

      Some people in temperate climates (such as UK) not fully exercising their right hand can get away without having a cooler fitted.

      However you would only need ten minutes on the autobahn in summer to need some (but not all) of the cooling capability of the cooler.

      And that is the rub—for the vast majority of the time you could probably be OK with no cooler but there could well be some instances where you need some of the coolers performance—but in all probability not all of its capacity.

      In your situation I think I would play it safe and fit a cooler—but would also fit an oil thermostat to prevent the cooler overcooling the oil.

      That is my view and my recommendation but– at the end of the day–the decision is yours.

      HTH

       

       

    • #11716
      michael roberts
      Participant

      Hi Richard and David,

      Many thanks for your replies – really helpful. I’ve ordered the frame with oil in the frame fittings, but I might see if I can fit the original Triumph oil tank, as I suspect it holds a bit more oil. Also, the oil should warm up more quickly on short runs. In that case, I will fit the original cooler and a Madigan thermostat. Oil in the frame saves some hassle in fitting stuff, but I’m still a bit concerned about how clean the inside will be. I’ll be fitting a filter on the return line, but I see the ability to get the tank off and give it a good clean as an advantage.

      Mike

    • #11718
      David LordDavid Lord
      Participant

      Richard, out of interest where was the 85deg measured?. I’m asking because I’m measuring oil temp in the tank and I wonder how much higher it is within the engine e.g. at the bearing surfaces.

    • #11720
      richard beard
      Participant

      Hi David—the 85C oil temperature spec referred to the bulk oil temperature—that is the temperature of the oil in the oil tank.

      Very localised oil temperatures –for example between the crankshaft and the shells would of course have been higher. But that oil would then be mixed with other cooler oil –for example spill from the OPRV –before returning tio the tank–either directly as in your case or via a cooler as per the standard configuration.

      HTH

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