oil tests & discussion

daveforty · Sep 22, 2023

Could someone point out where the comnoz oil test thread is posted? I read it some time ago, but cannot find it now.

Thanks in advance.

Tornado · Sep 22, 2023

Found the link here, under Resources page, "Best Oil" titled thread:

What is the best oil for a Norton Commando?

Norton Commando Motorcycle Oil Tests by Jim Comstock.

www.accessnorton.com

This used to be under the Technical Information thread, a sticky thread top of the Norton Commando forum.

robs ss · Sep 22, 2023

or... Aug 21, 2018

Onder · Sep 22, 2023

Well done! You sneakily started an Oil Thread!

daveforty · Sep 23, 2023

Onder said:
Well done! You sneakily started an Oil Thread!

I wouldnt be that naughty... I wanted to re-read it to remind myself of some of the conclusions. I have decided which oil I will now use on my Commando on the basis of those tests, I was curious how the conclusions may relate to a 70s Japanese 'superbike' with a wet clutch and shared engine / gearbox oil.

concours · Sep 23, 2023

daveforty said:
I wouldnt be that naughty... I wanted to re-read it to remind myself of some of the conclusions. I have decided which oil I will now use on my Commando on the basis of those tests, I was curious how the conclusions may relate to a 70s Japanese 'superbike' with a wet clutch and shared engine / gearbox oil.

Picture of the superbike please, to confirm oil-thread validity.

daveforty · Sep 23, 2023

not my bike, it is my mate's 1974 Z1a. A quick read of the conclusions suggests that the Royal Purple oils arent suitable for bikes with wet clutches.

It is a very tidy bike - original exhausts etc, originally registered in New York then imported to the UK some years ago.

Fast Eddie · Sep 23, 2023

daveforty said:
not my bike, it is my mate's 1974 Z1a. A quick read of the conclusions suggests that the Royal Purple oils arent suitable for bikes with wet clutches.

It is a very tidy bike - original exhausts etc, originally registered in New York then imported to the UK some years ago.

Correct, RP not good for wet clutches. The Bel Ray was the best clutch friendly oil on Comnoz’ list. Not sure of its suitability for a big Z tho?

Come on then, spill the beans, what did you decide upon ?

daveforty · Sep 23, 2023

For my Commando and T140 I have taken to using Castrol XL 20/50 - seems to have come out well on Jim's tests. And I no longer thrash the bikes around like I might once have done, or do high annual mileages. I did use GTX back in the days when it was 20/50 and was one of the oils specified in the T140 owners manual.

Z1 oil under discussion, seems that Kawasaki forums have similar threads / discussions...