forks

[derek taylor]

forks keep topping (banging) have no checked oil yet do you think it wants topping up.?

[bsa-bill]

If it's been in there for some time I wouldn't top up I'd drain and refill, that way you can put in the correct amount (213 cc if mem serves -check tho)  and see how it goes.
it can get prettu grotty if water gets in there

[derek taylor]

thanx bill

[morris]

5 ½ fl.oz Bill, which corresponds to 231 cc, so your memory is still all right
4 fl oz (100 cc) for early models up to 54

Might be worthwhile to experiment with different grades of oil, to find the best ride to your taste Derek
I ended up with the oil I use in the gearbox, which is Penrite's gear oil 30 mainly because I had it on the shelve
They do have a range of specific fork oils for classic motorcycles though;
http://www.penriteoil.com.au/products-categ.php?id_categ=14&id_subcateg=75

[RichardL]

it can get prettu grotty if water gets in there

Thinking about this, I'm wonerding if it might pay to do a pre-wash with a light petroleum product like kerosene, motvating the forks, as possible, to let the bushings do some cleanup.

Now about the word "grotty", I had never heard it outside of the slang that started with California sufers in the '60's, like at Malibu and County Line, but it was "grody". I was there. Both forms originating from "grotesque" according to the internets.  Surfs up djiude!

Richard L.

[muskrat]

The problem with external spring forks is that water & dirt gets in to sit on top of the seals. Seals don't last long and the stanchions rust. In 30 odd years I've replaced the 51's 3 times.
For anyone who hasn't had the forks apart for a long while, figure in a few extra $$$$$.
Cheers

[bsa-bill]

which corresponds to 231 cc,

that's the one Morris,  my dyslexic typing again, someone explained to me , it happens when your fingers work faster than your brain --- that could well be it

Richard, your expiation from Grotesque makes sense, in UK it denotes filthy mostly but also used as a general derogatory term for anything you don't like at the time