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Pete Murphy
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Can anyone point me at the English description of the numbered parts in the attached parts illustration? Also can someone confirm What type of metal part 44 is made of? Is it brass?

Cheers,
Pete

  • fork.jpg
schrader7032
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VBMWMO #7032
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Consider this PDF

Consider this PDF file:

http://www.beemergarage.com/documents/R515306.pdf

The diagram looks like the same...find the German words and use Google's translator to find an English equivalent.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

Pete Murphy
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Thanks

Thanks Kurt, that's a great help.

VintageSalesand...
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VBMWMO #7368
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material

Hi,

The material that was originally used is a Babbitt bearing material. I have seen reproductions in brass / bronze.

Jeff

Pete Murphy
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Questions Questions

Still a couple of questions.

Looking at the attached illustration above; how do parts 28 and 22 relate? The spring screws into part 22. Does part 28 cover the spring holder (22) and sit on top of the lower leg cover - part 52 (between 51 and 27 as shown on the other leg)?

Also the material for parts 44 and 5? Is part 44 brass? In pictures I've seen it doesn't look like steel. Also part 5? I can see why 44 would benefit from not being steel as it is static, but not sure about part 5.

Pete Murphy
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oops!

Hi Jeff,

Thanks for the info!

Just posted that question again at the same time as your reply Smile Is part 5 the same material or is it just steel?

Cheers,
Pete

VintageSalesand...
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VBMWMO #7368
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HI, Part #5 is made of either

HI,

Part #5 is made of either aluminum or phenolic. The spring screws into part #22, #28 threads onto the lower fork slider and covers part #22. The grey colored material that you have seen the lower bushing made of is Babbitt.

There is a long and thorough explanation of how to assemble this cloud of parts in Chris B's book.

Jeff

Pete Murphy
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Thanks again

Thanks for the info Jeff.

Pete Murphy
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out of interest, why?

Why would part 44 be made out of a bearing material like Babbitt? It's a static fitment. I can understand brass or another alloy that won't corrode with the steel tube. Is Babbitt just a cheaper option?

VintageSalesand...
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VBMWMO #7368
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Lower sliding bushing

Hi,

Part 44 is the lower fork sliding bushing - it is attached to the bottom of the fork tube, and slides up and down inside the lower leg. It must be only slightly smaller than the ID of the lower leg, because it also keeps the fork tube in a straight line. It does wear, and profits from being slippery. It is held onto the fork tube by a circlip ring.

Jeff

Pete Murphy
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aah!

Doh! I see! Thanks again Jeff.

I have a NOS Chinese fork on my bench now. All steel construction, and poorly machined in part. But otherwise pretty much identical to the early BMW. With a little work, and re-manufacture it'll do the job I think.

I'll share some pics here, as the fork is re-worked and goes back together, if anyone is interested? If you are building a bike from a bunch of scrap with lots of missing stuff, as I am, these parts, with a little work are a life saver!

Another question:
Should part 21, the little 'piston' that fits inside the plunger (part 48) be a softer metal also? It is steel on the Chinese fork, as is part 48, which doesn't feel right? How close a fit to the inside wall of part 48 should part 21 be? I have 3 examples of these parts, that were made in China now, and they are all slightly different, and I wouldn't be comfortable fitting any of them

Cheers,
Pete

VintageSalesand...
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VBMWMO #7368
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Damper Parts

The little metal part #21 is steel. It fits in #48 not tightly.

Jeff

Pete Murphy
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Thanks again

Thanks Jeff.

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