G: Gearbox (Twin) Gearbox Lubrication

[vibrac]

I was about to use EP90 oil in the racing twin gearbox as I always have for many years (originally on my first twin I followed Richardson and I used the same oil as engine oil). I use standard bushes in the box so I guess I dont have to worry about bush corrosion. The engine (of course) runs on R
I just wondered what the current thinking is, has anything else got an edge for racing (std box) bearing in mind the low but very hard mileage this bike will get (NB dont worry about clutches and primary contamination)

 

[Bill Thomas]

I have done it for years,
Never thought engine oil was good enough,
It's all in the Name ! , Gear oil ?.

 

[greg brillus]

Tim Your a castor man.........Run it in the box as well.......that's what Reg Bolton told me he ran in his racer for all those years........i did the same in mine running the 5 speed cluster, never missed a shift. On a rebuild a couple of years back , the internals looked like new........ And less drag than gear oil, give it a shot..........Cheers.

 

[roy the mechanic]

The manx box in my racer was very happy on R 40 for around 30 years. I got fed up of stripping it and finding no problems. The street rap uses Fuchs light gear oil. Roy.

 

[Gerry Clarke]

I can vouch for Castrol R as a wonder oil in gear boxes. I stripped a Velocette KSS gearbox recently, that I know has very mileage and hasn't been apart since 1970 with R40 in it since that date. The gears were astonishingly clean and free from wear, and the bearings were all reusable.

Gerry

 

[Peter Holmes]

I have been using this oil for years, I have a magnetic drain plug and there is never any bronze particles on it when I check it.

(wait for the reaction)

 

[Keith Martin]

We use Royal purple gear oil. rpo-01300
With the oil being purple you can see right away if it is gearbox oil or engine oil leaking.