CB160 Steering Damper Knob Restoration.

[AshimotoK0]

Well I got lumbered (only joking Jim  ) with one of a good mate's problems again. He's restoring his 1965 CB160 but the steering damper knob top was only half there when he bought the bike and he didn't get the missing broken bit 

Here in pictures is my 'restoration' of it.

The knob was originally made of hard black phenolic thermoset plastic. (like the body of old 13A plugs).
I decided to restore it with epoxy heavily filled with ultra-fine ceramic powder that sets rock hard. (the same RS 2-part epoxy I use for my coil refurbs).

The problem is the underside of the knob has convolutions that act, along with a springy clip thingy, as a detent mechanism, so I had to come up with a method of faithfully reproducing them.

I used hot melt adhesive  run into the underside of the knob to make a mould part for the convolutions. I used a slight smear of silicone oil (same as I use in gauge dampers) as a release agent to stop the adhesive sticking to the damper knob plastic.

Here is the broken part with the hot-melt profile pictured next to it.

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Then the mould part fitted to the broken knob

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I drilled the knob and glued in 1mm pins to give reinforcement.

Then I used Blu-Tack to form the outside of the mould and filled with the ceramic filled epoxy compound

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The part with moulding bits removed and rough finishing before final fettling and paint.

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After fettling and painting...pleased with the result ! Paint needs knocking back a bit but I will leave that to Jim !
 
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[AshimotoK0]

Underside after repair but before paint.

Forgot to say almost identical knob on the CB250/350K0 models.

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[McCabe-Thiele (Ted)]

Neat work Ash.👍👍👍

[Spitfire]

Very neat and precise work, love it when a plan comes together.

Cheers

Dennis

[K2-K6]

Good work Ash and interesting combination of materials etc.

Sounds like a good amalgam of parts in the mix of ceramic and epoxy base to give that characteristic rigidity in final product.

[Rozabikes Tim]

Brilliantly well thought out as one would expect from you Ash.

Have to say at one point I thought you'd dropped your dentures onto your work.😜

[McCabe-Thiele (Ted)]

That would be the first photo Tim the primordial soup.😁

[AshimotoK0]

Brilliantly well thought out as one would expect from you Ash.

Have to say at one point I thought you'd dropped your dentures onto your work.😜

Ha ha ... thought someone would pick up on the dentures lookalike moulding. Still have my own gnashers thank God

[JamesH]

You're a clever sod Ash. Love it.

[Johnny4428]

That’s a great repair! Excellent job Ash!

[Laverda Dave]

Is there no end to your talents Ash! Microwave dent pullers, capacitor mods, sealed ignition coil overhauls, false teeth repairs and now steering damper knob rebuilds, amazing work and attention to detail 👍.
If I give you a fully working CB160 steering damper can you build a complete CB160 around it for me please🙂

[AshimotoK0]

Is there no end to your talents Ash! Microwave dent pullers, capacitor mods, sealed ignition coil overhauls, false teeth repairs and now steering damper knob rebuilds, amazing work and attention to detail 👍.
If I give you a fully working CB160 steering damper can you build a complete CB160 around it for me please🙂

Needs must sometimes Dave. Some stuff is just not around any more or when it is , at a price that is pure extortion.  My next 'project' and one for myself this time,  are  the pesky alloy blocks that mount the flyscreen to the headlamp on the CB92 Benly sport.

I have a lot of history with these... acquired two pairs for my own '61 CB92 (one pair I found in a box of non-motorbike related old crap I got with the stash of bits/bikes I got from a garden in Crawley, long before I got my CB92 project) and the other pair came with my bike project. Got a mercy call last year from a friend of a friend who was severely depressed and needed to finish his CB92 so I donated a pair for free. Then, gathered the bits together for my own bike and couldn't find the 2nd pair after endless searching, so, in desperation I begged a dealer I know to sell me a set for £60 (normally a lot more than that but he took pity on me).

Now I am in need of a second set (don't ask me why, and NO I didn't lose the pair I bought) BUT no way am I throwing myself to the vultures that sell CB92 parts, so I am going into the place my brother used to own, that has a non-ferrous metal foundry, to cadge some fine moulding sand and I am going to cast myself a set.

Here are the little b*stards:-

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[taysidedragon]

Should be able to mill those from solid aluminium.

[AshimotoK0]

Should be able to mill those from solid aluminium.

They have double curvature surfaces on them ... well beyond my machining skills and to pay somebody to draw up and make them would probably be as expensive, or even more, than tracking down a used OEM set.

[taysidedragon]

Should be able to mill those from solid aluminium.

They have double curvature surfaces on them ... well beyond my machining skills and to pay somebody to draw up and make them would probably be as expensive, or even more, than tracking down a used OEM set.

Fair enough.