Big tube swingarm

[Mal S7]

I am getting ready to disassemble the R100/7. I only have til April before I live a little and take off for a week down South!
OK April may seem a longggg time away to some, but I don't get many leisure hours these days.

Anyway, I am thinking of easy improvements while its apart so I am on the lookout for a big-tube swing arm off a later model. I have located one cheap on ebay, but its in Germany (by Gummikuh) and the postage, of course, tempers the deal. http://www.ebay.com.au/itm/Schwinge-Kar ... 500wt_1414

My question is, are they the same swing arms on the later model twin shock R65?

Thanks
Mal

[SteveD]

Different according to pn'S Mal. The 650 might be shorter in the wheelbase...maybe seen by a shorter swingarm

R100
33 17 1 240 459 REAR WHEEL FORK BLACK (to 09/80) 6 NLA
33 17 1 242 236 REAR WHEEL FORK BLACK (from 09/80) $601.20

R65
33 17 2 301 233 REAR WHEEL FORK BLACK (from 09/80) $282.83

[Mal S7]

Thanks Steve.
I found a seller on US ebay with one from an R65 saying it fits the other models but I will stay away.
Another one off a 84 RS has turned up in Texas, bid starts at $8,looks like they pulled it from a lake but.

[vanzen]

Just to clarify:
The R65 SA is, in fact, shorter than that of other R models.
However,
to say that the 65 SA will "fit" other models is,
with qualification,
also a true statement.

The SA (with drive-shaft) will "bolt-right-on"-
but also shortens wheel-base
and alters effective suspension geometry.

[Major Softie]

Vanzen, how much shorter are we talking here?

[vanzen]

My notes (i.e. maybe not accurate)
list the WB of a 2-shock R100 @ 1465mm
R45, R65, R65LS @ 1400mm

I will suspect that MOST of the difference
is a result of SA length.

[barryh]

At 1390mm 78-80 R45/65's are shorter than the 81- 84 models which may mean an even shorter swinging arm as the part No's are different.

[vanzen]

The R65 SA part # difference in 1980 certainly indicates
the change in design we refer to as "big tube".

Even as the WB also increased by 10mm in1980.

So the question I must ask is this:
Is it SA length or some other relevant factor
such as
the change of forks design / manufacturer
that is responsible ?

[Mal S7]

Thanks fellas. My guess too is the shorter wheelbase is more than just the SA length.

But what wonderful cafe's they make!


BMW_cafe_racer2 by pipeburn.com

[Mal S7]

Well, I finally got me a big tube swingarm from an 82RS on ebay. It's being posted from Cairns, delivered for around $90. If it's straight as described I will be happy.

But .... I don't think I am going to make it in time to have it fitted for the ride to Victoria . The clock is ticking.

Will need new later style bearings - Munich in Perth want $100 each! They are about $80 a pair with seals from Motorworks in the UK, but that's going to be another two week wait. gahh patience patience ..

I also need to modify the brake light switch and the hardest part, swap over the driveshaft.

Tried today to pull the splined bell off the taper.



I used heat and modified an old puller, a machining exercise when I was an apprentice. It took an awful lot of force to break my old puller.