R60/6 - Which Progressive Suspension Spings SHOULD I have?

[gossamerjohn]

I just received my Progressive Suspension fork springs and there is a discrepancy between the sellers website and the information I received.

Can someone please tell me what the part number or length and width specs of the progressive suspension fork spings SHOULD be for an R60/6 (1976)?

Thanks

[vanzen]

I have lengths for /5 and /7 springs ... but not /6 unfortunately:
R60/7 – length of fork carrier spring (relaxed) 567mm, 22.32in
BMW manual does not list a diameter ...

sorry, not a definitive answer – but in the absence of reponses from others that know the answers ...

wouldn't it be possible to compare the Progressive springs to the stock ones ?
diameter should be the same –
or, the I.D of the stanchion must be at least 5mm larger than the diameter of the spring (from Progressive)
length will be approximately the same –
allowing for the fact that the old stock springs might be worn and slightly shorter than stock length.
if the Progressives are a little shorter, a PVC-pipe spacer can be used to take up the slack
PVC pipe is used to adjust preload, in any event.
if the Progressives are significantly longer –
my experience with Progressive springs and airheads is that their springs are extremely STIFF (!),
and do not want or need much preload, if any ...
...if they are significantly longer, you probably got the wrong part# !

from my limited and incomplete experience:
Progressive made 2 length springs to fit the Type247 BMW –
the shorter of the 2 were for 1981-1984
(I know this because I purchased a set for an 81 years ago, got the wrong set ... and had to cut them down)

hope that helps.