Author Topic: Spacer disc between primary cover and crankcase  (Read 1811 times)

Offline Peter in Aus

  • Valued Contributor
  • ****
  • Join Date: Feb 2014
  • Posts: 431
  • Karma: 2
  • South West, West Australia
Dose some one know or can measure the thickness of the 42-7518 spacer disc between the inner primary cover and the crankcase on the A7/10 SA please, I want to make one.
Peter

Busselton West Australia
49 A7 longstroke
58 A10  SA

Offline BagONails

  • Valued Contributor
  • ****
  • Join Date: May 2021
  • Posts: 310
  • Karma: 4
Re: Spacer disc between primary cover and crankcase
« Reply #1 on: 19.06. 2021 05:38 »
Hi Peter, Just so happens my one is fully exposed currently and it measures 2mm thick and seems to be aluminium or aluminum if you prefer  *eek*

Now I'm not saying that is the correct thickness, its just what is fitted on my m/c...also my scale says 'standard at 20C' and it is a bit brass monkeys here today in Adelaide, well cool for here at 15C ... but I think 2mm would be fine.

Cheers Ian
Ian
59 GF A10
67 Spitfire under resto
2013 kwaka W800 Desert Sled (ex write off)

Nil Desperandum

Offline RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 6483
  • Karma: 55
Re: Spacer disc between primary cover and crankcase
« Reply #2 on: 19.06. 2021 06:07 »
Original is steel.

Richard L.

Online berger

  • Wise & Enlightened
  • *
  • Join Date: Nov 2017
  • Posts: 3218
  • Karma: 22
  • keith.uk 500sscafe.norbsa JDM honda 750fz
Re: Spacer disc between primary cover and crankcase
« Reply #3 on: 19.06. 2021 13:34 »
steel one is 3/32 or about 2.3 milligrammeters

Offline bikerbob

  • Resident Legend
  • *****
  • Join Date: Feb 2011
  • Posts: 680
  • Karma: 8
Re: Spacer disc between primary cover and crankcase
« Reply #4 on: 19.06. 2021 16:44 »
I would check first to see if that spacer is needed, on my 1956 A7 S/A I had to remove it because it was putting to much pressure on the inner casing between the crankcase and the bracket on the frame beside the footrest.
56 A7 s/a
63 A65

ironhead

  • Guest
Re: Spacer disc between primary cover and crankcase
« Reply #5 on: 19.06. 2021 23:43 »
Without the spacer, you need to make sure the 3x 5/16" screws holding the front section of the outer cover do not protrude through
the crankcase too far & foul the crankshaft.

Offline Peter in Aus

  • Valued Contributor
  • ****
  • Join Date: Feb 2014
  • Posts: 431
  • Karma: 2
  • South West, West Australia
Re: Spacer disc between primary cover and crankcase
« Reply #6 on: 20.06. 2021 00:38 »
Thank you all, a few good tips there. I will make a 2mm thick one and see how it goes. from memory, the last SA I did I had to pack washers out where the inner primary cover bolts to the frame, will find out when I fit it to the frame and that is a long way off yet. *beer*
Peter

Busselton West Australia
49 A7 longstroke
58 A10  SA

Online chaterlea25

  • Wise & Enlightened
  • *
  • Join Date: Jun 2009
  • Posts: 4130
  • Karma: 54
Re: Spacer disc between primary cover and crankcase
« Reply #7 on: 20.06. 2021 12:42 »
Hi Peter,
The spacer was introduced when the full rear chaincase became an option , I think in 56? The position of the rear case is dependant on where the clutch scroll fits into the sliding plate.  There were /are different depth tapers on the clutch shaft adaptors..
It can be a PITA  to build a bike from bits and get this right
Recently when going about fitting an electric start kit to my SR, the instructions said to check with a straight edge along the crankcase/primary joint face to see if it is parallel to the gearbox plate/ frame mounting...
A very small difference here causes a much bigger distance between  engine and clutch sprockets

John
1961 Super Rocket
1963 RGS (ongoing)

Offline Peter in Aus

  • Valued Contributor
  • ****
  • Join Date: Feb 2014
  • Posts: 431
  • Karma: 2
  • South West, West Australia
Re: Spacer disc between primary cover and crankcase
« Reply #8 on: 21.06. 2021 01:02 »
Thanks John, I started this project with a bent frame and building it up from there so I can see I will have some fun when I get to that stage  *eek*
Peter

Busselton West Australia
49 A7 longstroke
58 A10  SA

Offline Colsbeeza

  • Resident Legend
  • *****
  • Join Date: Aug 2015
  • Posts: 734
  • Karma: 5
Re: Spacer disc between primary cover and crankcase
« Reply #9 on: 21.06. 2021 04:19 »
Hi John,
Apparently my bike did not come with the optional chainsaw. I had to buy my own *roll*.
Col
1961 Golden Flash
Australia

Offline BagONails

  • Valued Contributor
  • ****
  • Join Date: May 2021
  • Posts: 310
  • Karma: 4
Re: Spacer disc between primary cover and crankcase
« Reply #10 on: 21.06. 2021 04:58 »
Hi John,
Apparently my bike did not come with the optional chainsaw. I had to buy my own *roll*.
Col

 *fight*

 *yeah* *beer*
Ian
59 GF A10
67 Spitfire under resto
2013 kwaka W800 Desert Sled (ex write off)

Nil Desperandum

Online chaterlea25

  • Wise & Enlightened
  • *
  • Join Date: Jun 2009
  • Posts: 4130
  • Karma: 54
Re: Spacer disc between primary cover and crankcase
« Reply #11 on: 22.06. 2021 01:20 »
Fixed,
that what happens when the phone decides to predict the next word  *razz*

John
1961 Super Rocket
1963 RGS (ongoing)

Offline RDfella

  • Wise & Enlightened
  • *
  • Join Date: Aug 2017
  • Posts: 2210
  • Karma: 15
Re: Spacer disc between primary cover and crankcase
« Reply #12 on: 22.06. 2021 12:08 »
I HATE predictive text. Now and again my phone reverts to that, whereupon typing a text message results in utter gibberish. Then takes a minute or two to switch the damned programme off. Why do they have such irritating functions?
'49 B31, '49 M21, '53 DOT, '58 Flash, '62 Flash special, '00 Firestorm, Weslake sprint bike.

Offline bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Spacer disc between primary cover and crankcase
« Reply #13 on: 22.06. 2021 12:47 »
Why do they have such irritating functions?

because old bikers tend to have big thumbs and phones have small keyboards.
If left to my own I can make far more mistakes than my phones predictive do dah does
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline RDfella

  • Wise & Enlightened
  • *
  • Join Date: Aug 2017
  • Posts: 2210
  • Karma: 15
Re: Spacer disc between primary cover and crankcase
« Reply #14 on: 22.06. 2021 13:32 »
"If left to my own I can make far more mistakes than my phones predictive do dah does "
Not on my phone! Just reverted to predictive and typed 'weather'. Up came 'wealhidesss'. Typed 'going' and got 'Homogigoni'. Like I said - utter gibberish and the irritating thing is the phone often decides to default to that cr@p.
'49 B31, '49 M21, '53 DOT, '58 Flash, '62 Flash special, '00 Firestorm, Weslake sprint bike.