Search found 11 matches

by pkrpkr
Thu Oct 08, 2020 10:08 am
Forum: Vintage (1948-1969) Motorcycles
Topic: Tank mounting question
Replies: 2
Views: 123

Re: Tank mounting question

Thanks Kurt!
It's clear now I'm missing the horizontal bar.
by pkrpkr
Thu Oct 08, 2020 6:53 am
Forum: Vintage (1948-1969) Motorcycles
Topic: Tank mounting question
Replies: 2
Views: 123

Tank mounting question

Can anyone enlighten me with mounting details for my standard R69S tank? At the front it attaches with a bolt but how is the tank attached at the rear? There are no lugs at the tank rear and I can't imagine it just rests on the frame tube metal to metal. On mine there where rubber pieces between the...
by pkrpkr
Fri Sep 18, 2020 10:15 am
Forum: Vintage (1948-1969) Motorcycles
Topic: WATCH OUT: New production ignition advancers
Replies: 19
Views: 2313

Re: WATCH OUT: New production ignition advancers

Thank you very much James for this great info. My R69S always ran hot, even after installing a new advance unit in 2005. So I never rode much with it. After seeing your video I measured and the difference in lift of the lobes is 0.2mm! While the runout on the shaft it's mounted on is less than 0.05m...
by pkrpkr
Mon Sep 07, 2020 11:17 am
Forum: Antique (1923-1945) Motorcycles
Topic: For which bike are these cylinders?
Replies: 1
Views: 161

For which bike are these cylinders?

Can anyone help identifying two sidevalve cylinders I have found? The piston diameter is approx. 70mm so I presume about 500-600cc on a twin.

Thanks,
Peter
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by pkrpkr
Mon Sep 07, 2020 11:14 am
Forum: Antique (1923-1945) Motorcycles
Topic: Advance timing cable hookup - r11/r12
Replies: 4
Views: 542

Re: Advance timing cable hookup - r11/r12

On mine I have another end on the cable, it's more like a small lead cylinder soldered on, that slips between the two round brass tabs. At the bottom of the tabs there is a hole drilled where the lead cylinder goes to not slip out. Perhaps your end is the correct type, I don't know. The little black...
by pkrpkr
Thu Sep 03, 2020 10:41 am
Forum: Antique (1923-1945) Motorcycles
Topic: How do R12 valve stems get lubricated?
Replies: 0
Views: 482

How do R12 valve stems get lubricated?

Can anyone tell me how the valve stems in an R12 get their lubrication? There are two 4mm holes. One is at the base of the cylinder head. The other is in the case at the bottom of the tappet chamber. However they don’t line up and they don’t form a nice open passageway for oil. On my other (older) e...
by pkrpkr
Wed Aug 26, 2020 5:51 am
Forum: Antique (1923-1945) Motorcycles
Topic: Valve guide clearance R12?
Replies: 3
Views: 343

Re: Valve guide clearance R12?

Thanks for the input. On further measurement I discovered that the valve guide hole was not exactly straight. So even with the proper inner diameter of the valve guide at all spots and it moving freely at room temperature, the exhaust valve stem could have gotten too close to the valve guide sidewal...
by pkrpkr
Mon Aug 17, 2020 2:31 pm
Forum: Antique (1923-1945) Motorcycles
Topic: Valve guide clearance R12?
Replies: 3
Views: 343

Valve guide clearance R12?

The cylinders of my R12 had the holes for the valve stems worn so one of our specialists put in brass inserts. After the first couple of minutes riding the cylinders got hot (200+ Celcius), an exhaust valve got stuck and the valve guide had a press fit which was a bit too loose so it had moved. The ...
by pkrpkr
Mon Jan 29, 2018 5:33 am
Forum: Antique (1923-1945) Motorcycles
Topic: Torque value R12 gearbox clutch sprocket?
Replies: 0
Views: 129

Torque value R12 gearbox clutch sprocket?

Does anyone have a suggestion for tightening torque of the flat nut on the sprocket on the front side of the R12 transmission (that drives the clutch plates)?
All torque tables I see are for a regular hight nut, but this is a flat nut. I don't want to screw up the threads.
Thanks.