Grease level in BA box

[Keith.owen]

Hi all,
On simple inspection, by removing the filler cap, what should the grease level be after top-up of a Burman BA gearbox?

Keith

[Dave.Barkshire]

I'd be interested to know the 'correct answer to this'. I know that there are many views about gearbox grease and mine are almost certainly not correct.

I used grease-oil in my 37NH although it would escape to the clutch as the bearing was not sealed and this made the clutch stick a little so clicking into first was often physical. The remedy was to be liberal when topping up and this seemed to work. I seem to remember Len Ore saying he'd chuck in some old engine oil just to fill in the gaps that hard grease might leave.

[Keith.owen]

Hi Dave,
I just want to keep it good. The box is beautiful and just clicks through the gears, almost instantly, as I change.

I initially filled it with Penrite.

Keith

[simon.holyfield]

Where do you guys buy Penrite oils? I bought some 40w/70 for the Square. I'm still having to sit down after paying for it.

[nevhunter]

For years now I have been premixing oil and grease. I use a gearbox oil and Hi temp wheelbearing grease. The seal has to be reasonable . The original is becoming hard to get so the modified one might have to be sought. Grease doesn't flow and may just channel and run the bushes dry. You can drain the CP , but not the BAP. I just top up and put the bike in a gear on the stand and run the engine a bit above idle. Add lubricant till you can see it churning through the filler hole (BA) and use a wood dipstick with the CP. and not running. Nev

[Keith.owen]

Hi Simes and Nev.

Simes, I only use the grease from penrite - it costs about £5 a bottle. I shall probably mix my own in the future.

I use Sylkolene Chatsworth SAE 40 for my engine.

Nev, thanks for the input. The bushes are a bit of a concern - mine do have a groove to help lubricant flow along their length , but pure grease would be an issue in this respect. I half suspect that wearing of the gears only really starts to become an issue when there is excess lateral movement of the shafts due to worn bushes / bearings.

[nevhunter]

Grease is only a lithium based soap with oil in it. I would rather run a good gear oil if it didn't leak. There is a modified seal retainer available and if you harden the sleeve it runs on you will get good service. The recommendation in the later boxes is( I believe) engine oil. which the main producer of vehicle gearboxes in australia said doesn't meet spec for their boxes anymore. I'm sure if you contact a respectable oil company they will tell you the same. If the bearings wear the running clearances are incorrect and the gears aren't running with the proper geometry. If you roll two straight cut gears together you will notice a point where the sliding of the surfaces goes from one direction to the other, and stops in between. It is at this point the oil film has a hard time doing it's job, so you need a reasonable oil. Nev

[Keith.owen]

Hi Nev,
I think the only problem with using oil is that it will leak out of the kick start case, past the kickstart spindle and the gear change. I know some of the very later cases had a felt washer around the kick start spindle but I can't help feeling that it wouldn't be very effective with oil. As it is my GB weeps grease past the gear change!

Keith

[paul.jameson]

The correct amount of grease in a BA box is about two of my high pressure grease gun's full. If it doesn't leak out, the level is too low. If it leaks out, the correct level is when the leak stops. Add an egg cup full of engine oil every few years, or when 3rd gear whines more than usual. These instructions assume the use of semi - fluid grease. If you insist on using the hard grease, nothing will provide adequate lubrication.

[robin.parker]

I'm wondering why no-one has mentioned Morris's "Golden Film" Semi Fluid Grease (K400EP-NLGI No 00). I expect that is what Paul uses.
I've used it for years, in Porridge Boxes (and in my GB where it stops the oil leaking out of the speedo drive).