Author Topic: early 50"s bsa 500 twin a7 primary case query  (Read 845 times)

Offline bazooka

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early 50"s bsa 500 twin a7 primary case query
« on: 29.01. 2015 13:26 »
Hi all - I am a newbie to this forum -  *smile*

I have recently bought an early 50"s 500 twin. I was going to fit a later model casing (L/H side) over the primary chain when I noticed the oil level screws are different - original is screw at 8 o'clock and the newer casing it is the next lower screw to it. Is this correct and how can I set the oil level to match the older casing?

" if you don't ask you will never know"

Many thanks Baz

Offline Topdad

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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #1 on: 29.01. 2015 14:02 »
hi baz, saving Musky an icon , *welcome* , best provide abit more info ,year, plunger or swingarm etc. better still post an intro in members bikes and pics ,i think . We also like pictures anyay the  the guys will be able to sort this out asap.  best wishes BobH
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Online Greybeard

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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #2 on: 29.01. 2015 14:49 »
 *wave*
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Online muskrat

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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #3 on: 02.02. 2015 09:20 »
G'day bazooka, welcome to the forum *grins* (gotta get more smileys)
Is she a plunger or swingarm? The plunger likes a little more oil for the chain adjuster and the clutch is covered. If so, just grind into the higher hole inside the cover to let oil escape when it gets to that level.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Offline duTch

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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #4 on: 04.02. 2015 09:40 »

 Hi Baz- keep yer 'ookas' to yerself....

 When you say 'early '50's, I think Plunger frame (up to '57), if so, I can't see a later cover being compatible. If it's a early swingarm ('54-'58) different story, Folk with swing-arms may be more knowledgeable...I think there's a couple of different ones after '58, but I'll stay out of it
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #5 on: 04.02. 2015 10:02 »
Come to think of it, your right duTch. I have both plunger and swingarm. The two don't mix.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Muskys Plunger A7

Offline duTch

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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #6 on: 04.02. 2015 23:47 »

 All I know about Swingarm cases is (from memory) I think my '58 RR had same drain and level arrangement in the outer case as Plungers, and from discussions and photos on here, seems the later level and drain plugs were integral and screwed up from the bottom..but in which casing...??
 now I'll endeavour(spell-check questions that spelling, but my dictionary agrees) to stay out of it.. *smile*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline bazooka

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Re: early 50"s bsa 500 twin a7 primary case query
« Reply #7 on: 09.02. 2015 05:03 »
Hi all -- Thanks for all your input.

Bike is 1951 plunger. The original case has oil level on higher bolt hole. The newer case has it on lower hole. I have ground the higher hole of the new case to match the old case hole and filled with oil and all is OK. the level is correct - a simple fix as it turns out. As above there must be different holes for different bikes and the new case may be from a different model altogether.

Once again thanks for your help and I will post a picture when I work out how.
Cheers Baz