Author Topic: Gear change cam plate plunger or swinging arm?  (Read 1192 times)

Offline spanersc

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Another question to our knowledgeable readers. Are the gear change cam plates interchageable between a plunger gear-box and a swinging arm one? The BSA part numbers are different but does anyone know what the differences are and whether they can be swopped? Thanks again. Peter
Peter C    Cambridgeshire. UK   1935 Blue Star. 1950 A7 Rigid.  1952 A7ST.  1953 A7ST.  1953 A10 Super Flash.  1954 A7ST.  1955 A7SS.  1955 A10.  1956 A10RR.  1962 RGS.  1962 DBD34

Offline trevinoz

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Re: Gear change cam plate plunger or swinging arm?
« Reply #1 on: 13.03. 2011 19:47 »
Peter,
               They can't be swapped  as they have  different indexing apparatus.
  Trev.

Offline cosmikdebriis

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Re: Gear change cam plate plunger or swinging arm?
« Reply #2 on: 24.04. 2012 11:48 »
Ok so... How can I tell the difference from a photograph? I ask because there is one on eBay that looks the same from the... erm... side with the cutouts for the selector forks to fit in to. But no photo of the reverse, which, I'm assuming is the side you refer to as indexing?

Would it be possible to fit a cam plate from a later box along with some other associated parts or do I need the right plate?

Offline duTch

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Re: Gear change cam plate plunger or swinging arm?
« Reply #3 on: 24.04. 2012 13:14 »
Two photos front and back of PLUNGER camplate. Swingarm box has 'gear' type teeth on back, instead of the three 'grabby things...? '
 Inner covers are  different as is correspondingly associated mechanism, but I don't have examples to demonstrate.
 That's best I can do. cheers, duTch

NB this plate for some reason has two 'neutral notches' -?
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 cosmikdebriis

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Re: Gear change cam plate plunger or swinging arm?
« Reply #4 on: 24.04. 2012 18:29 »
Huge thanks for this as it confirms the one I've seen is the correct one... Whoopee

Only two neutrals... That's not a proper Brit bike box. *smile*

Online muskrat

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Re: Gear change cam plate plunger or swinging arm?
« Reply #5 on: 24.04. 2012 21:43 »
 PO might have tried to make a reverse cam plate. That would be a bugga to use. Gap between 3rd & 4th ain't big, and then to throw in a neutral  *problem*
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
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Muskys Plunger A7

Offline duTch

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Re: Gear change cam plate plunger or swinging arm?
« Reply #6 on: 25.04. 2012 09:37 »
Oh yes, I'm hearing you there!! Might as well grind in another one betwixt 2& 3,and make it 'REAL' fun, heck even though I've been running 'round on left foot change for about 25yr, I still get mixed up with feet-L/R/u?p/do?wn..where was I..?? , 3 neutrals'd be ultra- exciting-where's the next *beer*??

   Hey Pete glad to help, didn't realize it was you (but if I had would've done the same!!). Cheers duTch
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