Trevor S once dipped the oil tank of every bike arriving at a National Rally, and showed the results to a friend in the "oil applications" business. Based on these temperature readings (some bikes had done 10 miles, some 300) HIS FRIEND - NOT ADVISED OF WHAT THE READINGS HAD COME FROM (sorry, hit Caps Lock by accident) suggested that SAE 10 was appropriate.
Not an attack on Vic, who merely reports, but IMHO, Maughans are covering their arse(s). I'd like to see their evidence that 40 is the best grade, and how many miles THEY covered establishing this.
I'm running Morris 30, have done for 10,000 miles. "Naturally" the UFM is lagged with radiator foil to keep the oil temperature UP - which means that emulsification is miniscule - and when the Morris 30 runs out, I'll go to 20. Mobil1 is a bit pricey, although really an ideal 0-50.
Not that I think any of this is life-threatening. Vincents will run on anything with "oil" on the label. But don't feed me this stuff about running it on the oils available 60 years ago. The oils you buy now aren't the oils you would have been buying then anyway.
(I've always admired the Tim Kingham approach. Tim recognised that if R was good enough for race bikes, it was good enough for his Rapide. He also (probably) recognised that that Castrol made more money from selling mineral crap than by selling everlasting R. So they invented any number of reasons for not using R in road engines. Bullshit. The only downside is that it leaves orange stains on tee-shirts that cannot be removed. Don't ask. I've used it in my Rudge (three times through the Manx, then demoted to Rudge duty) for 10 years. Change? Every blue moon. Top up? As necessary. Problems? None. Drain the crankcase (it sumps), and it'll start first or second kick after months of inactivity. )
Not an attack on Vic, who merely reports, but IMHO, Maughans are covering their arse(s). I'd like to see their evidence that 40 is the best grade, and how many miles THEY covered establishing this.
I'm running Morris 30, have done for 10,000 miles. "Naturally" the UFM is lagged with radiator foil to keep the oil temperature UP - which means that emulsification is miniscule - and when the Morris 30 runs out, I'll go to 20. Mobil1 is a bit pricey, although really an ideal 0-50.
Not that I think any of this is life-threatening. Vincents will run on anything with "oil" on the label. But don't feed me this stuff about running it on the oils available 60 years ago. The oils you buy now aren't the oils you would have been buying then anyway.
(I've always admired the Tim Kingham approach. Tim recognised that if R was good enough for race bikes, it was good enough for his Rapide. He also (probably) recognised that that Castrol made more money from selling mineral crap than by selling everlasting R. So they invented any number of reasons for not using R in road engines. Bullshit. The only downside is that it leaves orange stains on tee-shirts that cannot be removed. Don't ask. I've used it in my Rudge (three times through the Manx, then demoted to Rudge duty) for 10 years. Change? Every blue moon. Top up? As necessary. Problems? None. Drain the crankcase (it sumps), and it'll start first or second kick after months of inactivity. )
