So finally our esteemed leader lifted our local down last Friday and the weather aligned, so on Monday I could go for a ride after not leaving the city in over 9 months, probably closer to year.
The first thing, science experiment (101), was to determine how the HiCam would behave on the open road in clean air.
Since putting in the Griso spring I also added a bit over a litre of oil to bring the level up closer to the underside of the Roper Plate, prior to this I'd been running at around 1/2 on the dipstick. Trawling through 40 pages of posts on the COG forum looking at oil threads specifically. I discovered the sumps should be filled up to the underside of the Roper Plate, around 10mm higher than the high point on the dipstick (COG quoted figures of 17mm above the high mark on the stick approx equal to the underside of the plate). Yet another lesson learned (thanks @Lucky Phil for posting about this earlier which initially drew my attenion to it).
TBH I'm still a bit sceptical about the broadsump design, my Sporti has the same setup and it tends to run on the hot side as well (not in the same league as the HiCam though).
Anyway, I found with the addtional oil it's a bit slower to heat in traffic, but still too fast for comfort.
Completed over 150miles, ambients in the low 20C. Once running in clear air my pressure varied, typically around 55psi 4k rpm in the 40-50mph region and 60-65psi when running 60mph and above again around 4k rpm. After running in clear air if I did get held up the pressure would drop into the mid 50s or thereabouts, but once back into clear air recover pretty quickly to 55-60 and if extended running I'd get back up close to 65psi. I'm relieved that on the open road the bike runs well and the pressures are high enough for it not to be a concern. Had a lot of fun getting it out into the bargain what a hoot that bike is to ride.
Idling after a clear air run pressure around 15psi at 1200 rpm.
I never got the chance to get data on the temps, but I'd hazard a guess (from experience with pressure and temps) in clear air oil temp is somewhere between 105-115C, high but not excessive enough to cause damage to the engine.
Once back into the city in a 30mph zone for 7 miles (or a bit more) with quite a few traffic lights, but no horrendous snarl ups, the bike was back to its old evil ways and about 2 miles from home was stalling at idle, the heat coming from the engine was obvious. Literally yards from the house the low pressure light came on at idle and revving a little showed the system was struggling to maintain pressure around 20psi as I recall at a little over 2k rpm. Checking the sump temp when I got it in showed 130 C on the gauge.
Going to check tappet clearances and open them up to 0.15 and 0.20 as recommended by Karsten per Lucky Phil's post (page #1) and recheck oil level. I still can't see oil at the base of the Roper Plate, pretty sure it can't be far off though.
I just cannot understand why it runs so hot, I'd heard that these engines have a reputation for it, but searching the COG and on here, all the evidence points to the opposite being true.
Over the Winter I'll be looking at a larger cooler and changing the 15/50 in her at present to a 10/60. The 10/60 will probably do very little but if it lowers the starting pressure and raises the running pressures even a little its all going in the right direction.
Hopefully I'll get it out again this summer to confirm the data