Hi Templer,
...and here is my write up on my thoughts as per my post a few months ago....
"""Firstly, forgive my rambling on.
When I built the tow behind trailer for my bike, I had a stainless steel cowling fabricated to direct more air through my radiator and assist with a extra cooling. (Pictures in Photo Gallery section). This mod has worked extremely well and maintains the coolant temp fractionally below centre on the gauge, towing a packed trailer in + 95degF ambient temperatures, at a cruising speed of +/- 75 - 80mph. My problem now is that my oil temperature with the extra load etc. is certainly a lot hotter than what I believe we would deem as a normal operating temperature. I have not actually measured the oil temperature, but based on the following, have come to my conclusion:
1. I use silkolene 20W50 oil
2. Normal use of my bike (without trailer) stop/start in and around town, high speed highway runs etc. the oil pressure warning light may flicker on/off at idle (8-900rpm)
3. when towing the trailer the light will come on permanently at idle and only go off at around 12-1300 rpm!!!
4. My relief valve appears to be working as stated in the manual - cracking slightly over 5bar.
This lead me to the conclusion that the hotter than normal oil will obviously have a lot less viscosity, be a lot thinner causing my pressure drop!
I have read posts where our members have spoken about header wrap and the like to direct excess heat from the headers and exhaust away from the block and sump, but there is the concern of damaging the headers. Most of our members talk about DG pipe etc. which I don't have! I have a Cowley 6 into 1 and have no idea if the headers will withstand the excess heat retention once I wrap them, so I have now decided to install an after-market oil cooler and will explain my thought process below, but would love to get some input (thumbs up or criticism) from our fellow technically minded members prior.
Parts I want to purchase for Mod
1. 10 Row Oil Cooler
2. 3.7 GPM 12v Oil scavenge gear pump
3. AN6 SS braided hose and relative fittings
4. small 'spin on' oil filter
5. thermo fan switch On 85DegC - Off 80degC
Installation:
Place Oil cooler below radiator. Oil suction to come from a modified 'O' ring sealed banjo fitting replacing existing sump plug. Run hose from sump plug fitting through to small spin on filter with custom machined filter head, to gear pump and then on to the oil cooler. From oil cooler back to a second modified 'O' ring sealed banjo fitting replacing our oil filler plug on clutch housing. So in a nut shell, take oil from the sump plug, cool it and then feed it back into the clutch housing.
Operation:
To maintain a normal operating temperature, we don't want the oil pump running continuously, so a thermo switch is fitted in the sump and connected through a relay to the pump - starting and stopping the pump as and when required.
I have also given thought to the fact that the pump may still kick in and out frequently with this set up and then pondered on the thought of machining a custom relief valve (replacing the OEM valve) that can be installed with a fitting to direct 'overflow oil' out to the oil cooler line, T'd in after the gear pump. The relief valve should vent some oil at normal cruising speed and therefore should add a little extra cooling of the oil, preventing the gear pump from kicking in and out as frequently. Obviously there is a lot of machining and mods to the sump to accommodate my thought process.
Placement of the Oil Pump and filter:
The stock air box will be removed, and converted to pod filters as described by zed_thirteen (thank you zed_thirteen) in the carburettor section. The now free space in front of the battery will accommodate the pump and filter.
I hope all makes sense to our members and would really like to get some feed-back.
I have attached a basic circuit diagram, but note that I haven’t yet finalised the fittings required, so please don’t take those as confirmed yet."""