I'M SO EXCITED!
I'm sure those of you who already use this oil already know about it...but here in Denver, it is not available in most shops. I found it at a motorcycle junkyard who specializes in shredding CB750/500/550 bikes and sending thee pieces to UK for their boneyards.
It is the Bel-Ray "MINERAL" EXL in 20w50. Since it is SM and JASO MA2 (i.e., zinc-less, compared to what we need) I added some zinc to it, too.
In 2 minutes of startup time, the bike settled to a solid, smooth idle. I have been wrestling with the old "keep it alive" throttle nudge at idle since I rebuilt it, presuming the extra-tight bearings I've installed were not yet broken in sufficiently to let it idle. I was wrong! It is/was the oil.
Here's the chronology of the oils during this break-in:
1. First 80 miles were Shell Rotella 15w40, to wash out the engine assembly goos and sealant blobs that always seem to accumulate, and deposit them in the filter. It runs thinner than I like, but has low detergent and non-aggressive dispersants, so it removes the clingy sealant blobs around the edges nicely.
2. The next 200 or so miles were Castrol 4T 20w50 "Motorcycle oil". It's not bad, but not great.
3. The filter was then changed and new Castrol 4T 20w50 installed for another 300 miles. It began to smooth out and the rockers needed adjustment twice during this time, gaining almost .004" extra clearance on some valves. This is due to the parkerizing wearing off on the almost-new cam I installed, because the valves did not recede up into the head (as they would on a brand-new engine) to take up any of this slack. My valve seats are FIRMLY planted!
4. I installed the 'new' (2 years ago it was introduced, I think?) Valvoline 20w50 Motorcycle oil for wet clutches next. Right from the outset, the clutch did not like me finding Neutral. After I hit the hiway leg of my trips to work (18 miles of 70+ MPH interstate), the oil comes up foamy in the tank, and after about 5 miles of the hiway leg at speed, the oil cap feels hot and the engine is losing its edge. Even though this build has made a lot more power, I can feel it roll back on that power after these initial miles. After a cooldown, the full power comes back, but then fades again, especially when pulling mountain grades for miles at a stretch. And, the bike is a mess from the oil mist blowing out the vent tube, so I routed it over the chain side, and have been wearing my black windbreaker to avoid the racing stripe look up my left back shoulder...
5. Then, 42 miles ago I installed the Bel-Ray. I ran it 2 minutes then, and shut off. The next AM, I touched the Start button and the engine leaped to life, and immediately settled to an idle, stone cold. It hasn't done that since XLR Castrol disappeared! In less than 30 seconds I rolled off, with no stutter nor complaint: it hasn't done that very well since the rebuild, taking up to 2 minutes to smooth out. By 2 miles up the road, the gearbox felt brand new. By 5 miles up the road, I was riding too fast and bad to back off. When I got to the Interstate leg of the rip to work, I found myself nudging 90 MPH at less throttle than I had been running 70-75 before.
THIS is just like the old Castrol XLR oil performance I rode for 100,000 miles before it disappeared! The bike will easily top 100 MPH, begging for more, in mere seconds, singing that happy SOHC4 song again. This stuff is the real deal.
So now, I have to find some more: it was the last gallon bottle they had. I need a case. Maybe two cases....