Author Topic: A10 Engines  (Read 863 times)

Offline Ron B

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A10 Engines
« on: 28.01. 2012 21:41 »
A general question- What year or serial number did the A 10 engine get a thick flange barrel?  And what year or serial number did the A10 get a 356 cam?  And lastly, when did the three bolt crank enter the picture.  Somebody must know this bit of trivia. 
Thanks Ron B. 
Fridley, MN USA
1949 A7 Long Stroke
1950 B31 w/ M21 engine
1954 A10
1967 BMW R60/2

Online beezermacc

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Re: A10 Engines
« Reply #1 on: 29.01. 2012 09:17 »
The 356 cam was introduced at the beginning of the A10 in 1951 for the sports models A7ST and Super Flash and the A7SS when introduced in 54. The 334 cam, used on basic models, was dropped at the end of 58 and the 356 was then used on all models whilst the 357 was adopted for the sports models in 61. Thick flange barrels (67-1210) were used by all 650 models from 1958 and by the Sports models from 54. The use of three-bolt crank matched the thick flange cylinder application.
Priory Magnetos Ltd - A10 spares, magneto and dynamo refurbs. www.priorymagnetos.co.uk

Offline Ron B

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Re: A10 Engines
« Reply #2 on: 29.01. 2012 17:37 »
Thank you for the info.  I have a plain new no number crankcase with a 356 cam and three bolt crank plus  thick flange barrel.  I did not know what year this thing represents, now I have  an idea if what I have.  Thanks again Ron Bohm
1949 A7 Long Stroke
1950 B31 w/ M21 engine
1954 A10
1967 BMW R60/2

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Re: A10 Engines
« Reply #3 on: 30.01. 2012 00:51 »
The crankcases should have a year date stamping on the outside/front/bottom/nearside. Have a look at this expired ebay item http://www.ebay.co.uk/itm/290649718237?ru=http%3A%2F%2Fwww.ebay.co.uk%3A80%2Fsch%2Fi.html%3F_from%3DR40%26_trksid%3Dp5039.m570.l1313%26_nkw%3D290649718237%26_sacat%3DSee-All-Categories%26_fvi%3D1&_rdc=1
 scroll down to bottom of listing for pic of date stamping.
Priory Magnetos Ltd - A10 spares, magneto and dynamo refurbs. www.priorymagnetos.co.uk