SOBeemer service

Well I finished a bit of work on the RS last night. New "Featherlight"
throttle cables from Venhill, new carb gaskets and o-rings and a new
improved Bosch coil with leads and metal plug caps from motobins. It
already had new diaphragms last year. I have it on the 32mm Bings rather
than the 40's ATM. Put on one of those neat little cruise control
throttle screws too.

I checked the works manual during a rain shower and noticed that it
quotes the late airheads for a tickover of 800-1100RPM. I can usually
get them all settled nicely at 600 but I put it at 800 anyway. There is
still no perfect trade off between balance at high revs and clean pick
up on both cylinders off the idle, so I set it somewhere towards the
latter. I reason that CV carbs should compensate somewhat for slightly
uneven butterfly opening after a few seconds, sound sensible? it's
really nice to hear/feel that even pick up anyway. Makes no odds to full
throttle use anyway )

All in all it is running super sweetly, it ticks over without a stutter
and sat on idle for 10 minutes without a stall. Happy I am, may even
take it to IOM.

 

I still lust after that machine.

There was an *immaculate* 1978 one for sale at Kempton Park last
weekend. 22k from new, one owner since 1980, quite the cleanest, most
original one I've seen for years, full luggage, etc. Only downer was
the colour, which Timo summed up as Jewish Racing Gold - never the most
attractive RS option, that one. He was asking £3500 for it, which we
didn't think was really out of court for something so good.

 

You will get it for a spell after Cray has worked on it. Promise.

You know I just don't rate the early RS, although the late Brembo
caliper style is better, and I just can't see 3.5 worth in them. The
gold is hideous, black being the nicest IMHO with the smoke red close
behind.
Little known fact is they did a rather nasty custard yellow with brown,
yes really, though I only saw one in the UK. I did snaffle a tank out of
Park Lane in a clearance in said colour, **** knows why it had been
ordered in.
If memory serves me I was in an anti-paint period. I kept it bare steel
and regularly rubbed it down with oil.

 

Custard yellow. Nice.

I agree the old ATE calipers weren't a patch on the Brembos, but what I
really liked about the old RSs was the heavy-flywheel engine. I always
found it smoother and less buzzy than the later bikes. You could sort
of ramp the things up to 90-100, and roll off the throttle and let them
burp along.

My old 1978 RS (actually an S that had been RS-ised) had Progressive
fork springs, electronic ignition, and a 32/11 crownwheel.

Old pic here: http://www.chateau.murray.dsl.pipex.com/images/bmw.jpg

 

Sounds good.

I wasted one stock set on the RT - didn't realise they were PTFE lined
until I'd dutifully pumped several ccs of Duckhams' best down each side.

Which brings me to the question: are they *that* much better than
(non-oiled) normal ones? I see Motobins do them, did they come from
there?

Regards,

Simonm.

 

Yup from Motobins and yes they are very light and the throttles return
to the stops rather sharpish

 

Thanks. Sounds like this month's pocket money then.

Regards,

Simonm.

 

Just a thought... are the fork legs the same for ATE and Brembo brakes?
If I get my arse in gear and get the RS rolling again this summer like
I've promised my dad, I wouldn't mind ditching the ATE brakes.

Hopefully the new master cylinder I popped on a couple of years back
will suffice.

 

Nope completely different.

 

I have a friend who may be in the market for a sohc CB750. I've tried
dissuading her and even suggested a real girls bike (SV 650) she just
gave me a withering look.

Know of any? What's the going rate for a fairly good late Kx?

I had one once; it was utter shit.

 

Err... The fork legs or the master cylinder?

 

Forks

 

They are Venhill but bought through Motobins

 

I've got boxes of brand new, packaged, Venhill cables (clutch, brake,
choke and some speedo) for MZs (TS and ETZ). I really should get round
to putting them on eBay.

 

Let us know when you do, I could do with some for my
TS150...

Nick

 

Well, I finally fitted the Surefoot sidestand. Due to the exhaust
routing this is different on a mono. It took me an hour to figure it
out!! It mounts onto the back of the left footrest bolt and has a lug
which also secures to a spare hole on the exhaust/pillion frame bracket.
It sits quite far back and flips up under the pannier, this reminds me
not a little of an early MZ250. It works rather nicely however. Good
angle of lean. Can be flipped down/up with the heel while sitting on the
bike. Does not self retract but will flip back if left down on the move
and grounded. No longer made for the mono apparently, I've had it in the
box for ages.

 

They're for 250s mainly. I'll have a poke about and see if there are any
for the smaller bikes..

 

According to someone I spoke to at IIRC Motorworks, they were no longer
allowed to sell them for post-'83 bikes - something to do with C&U regs
requiring the use of the spring-back sidestand.

I met a guy up the town once who had an early RT with the Bob Porecha
version fitted. This just clamped to the frame below the footrest and
worked like a normal stand.

 

But lots of bikes here have non flip up stands shirly? maybe in
Germany? They are are goddam liability.

 

I know. It's madness.