Fastenings, fixings and 0 rings/fibre washer sizes

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martinaccarter
Posts: 35
Joined: 20 Aug 2022 20:42
Location: Cambridge

Fastenings, fixings and 0 rings/fibre washer sizes

Post by martinaccarter »

Hi All

I have a couple of questions arising from changing the fork oil. To remove the fork caps on a disc brake Strada I'm going to need what looks like a 12mm allen key. Before I go and buy one can somebody please confirm the correct size? Thanks

This has led me ask whether there exists a form of "table" for the Strada that sets out all the sizes of the fixings etc along with sundry "circular" items like fibre washers and o ring sizes (I'll need o rings when replacing the fork caps but I have no idea what size - please can someone advise?) My query is also prompted by the fact that I also have a Velocette Venom and many moons ago someone compiled such a table which proves very useful, particularly with regard to the myriad of imperial shapes and sizes involved! Thankfully something we don't have to worry about with the beautiful MMs!

Thanks in advance

Martin
3potjohn
Posts: 1243
Joined: 02 Jun 2007 13:58
Location: Devon

Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by 3potjohn »

A useful thing is to download the parts book from the documents in the member’s area. The part number helps when ordering stuff from Mdina Italia.
There is a Marzocchi fork manual at ducactimeccanica website. On my 82 Sport I undo the fork top nuts with a 30mm long spanner, which is not quite the best fit but some bikes have different forks I believe. Someone else should be able to provide other info.
Crankcase bearing sizes we do know!
Good luck.John
mbmm350s
Posts: 666
Joined: 22 Jun 2018 10:18
Location: Reading UK
Location: Berkshire UK

Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by mbmm350s »

Hi,
For early 350s (and others with Allen socket) I find it easier to use a 3/8 drive ratchet and Allen socket 12mm rather than an Allen key as the clocks get in the way. Go easy as it's not unknown for the heads to shear off. Do undo the triple T top clamp bolts.
Most bolt nut washer o ring and seal sizes are quoted in the parts book, so no need for tables.
Mark
martinaccarter
Posts: 35
Joined: 20 Aug 2022 20:42
Location: Cambridge

Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by martinaccarter »

Thanks for your replies. Both very useful indeed
BumbleBee
Posts: 140
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by BumbleBee »

Originally 12mm hex key, but after a lot of use/abuse occasionally a bigger size fits better. One of mine is 12mm the other is likely to round out if I use a 12 so I use something bigger that actually fits that one properly, a bit of empathy goes a long way with old machinery :-)
SupermotoDave
Posts: 344
Joined: 13 Apr 2006 18:38
Location: Reading UK
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Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by SupermotoDave »

So a 1/2”
BumbleBee
Posts: 140
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by BumbleBee »

SupermotoDave wrote: 25 Oct 2022 16:43 So a 1/2”
On the worn one yes. 12mm on the good condition one :D
mbmm350s
Posts: 666
Joined: 22 Jun 2018 10:18
Location: Reading UK
Location: Berkshire UK

Re: Fastenings, fixings and 0 rings/fibre washer sizes

Post by mbmm350s »

This site gives a table of reference for the OR series of o-rings. These can be cross referenced from the parts books. Note these are not necessarily standard metric but can be obtained readily from Simply bearings etc.
I have not validated the entries in this table so you should double check and don't assume that the part
you find in your engine is correct, it might have been replaced in the past.

https://www.thisoldtractor.com/o-rings_uni.html

Cheers
Mark
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