1961 BSA Super Rocket Rebuild

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Yes had those piston's in a hotted up P11 motor I pulled apart in the late '80s, the motor had come from USA so maybe an aftermarket period performance product?
 

Jerry Doe

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I would be curious about the pistons too.

Today I split the cases. The cam does not look too bad. It’s the 0357 high cam. I think it looks good enough to use, but I have to figure out how to measure it properly. They used larger crank journals on the later a10s, so I hope I have one of those. Crazy balancing holes on the crank too. In general other than grime, things look as expected. I don’t like how they center punched around the sump trap plugs. One things for sure the crank has been split before me as you might expect in 60 years.

Here are some more pics






 
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That camshaft looks good considering the glutinous state of of some of the rest of the engine....
Re: 'Large journals'... I've just been reading an article quoting Dave Degens in the 60's building race engines, and he questions whether larger diameters and high revs go well together (all to do with 'peripheral velocity')
Irrelevant to a cooking BSA, of course :)
 

MikeG

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The radially placed bolts holding the flywheel tell me it's a large journal crank. It does look like it's been balanced, and I noticed a big difference in mine after I had that done. It dod not diminish vibes that much, but it moved it to an RPM range out of where I normally am at cruise. Sludge trap has definately been out a few times. Look for new hex head plugs to replace them.
 
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it may be specs for North America were different , but my 1961 super rocket did not have a spitfire cam as standard... ( it was only 5 years old and unlikely to have been changed)Do get a comb for locating the push rods . and as its all apart investigate having an end fed crank conversion. Make sure the sludge trap is clean and be warned mine suffered from serious brake fade ie if braking down from 70 or so there was absolutely nofront brake from 30mph on .. I suspect the grade of iron used inthe hub.
Simple way to tell what youhave is from the numbers. Ithink all DA10 R had large journalcranaks and of course the heavier flanged base flanged cyclinders.
 

Onder

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+1 on the oil but one wonders if a lot of this is blow by pollution. You can have black oil in a thousand miles
if you suffer from this. Back in the day many bikers just soldiered on as long as the bike still ran.
 
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You can find some cam data here.
AGTS-library-bsa
FWIW I hate this zenforo stuff where they substitute the meta data for the link I insert!
The books show DA10R engines 60-63 came with 357
59 and earlier SR was 356
 
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You can find some cam data here.
AGTS-library-bsa
FWIW I hate this zenforo stuff where they substitute the meta data for the link I insert!
The books show DA10R engines 60-63 came with 357
59 and earlier SR was 356.

Surely it was only engines fitted to the Rocket Gold Star that had the 0357 spitfire cam as standard. My 1961 had the 0356 cam derived from the Road Rocket . It may be the 0357 was available as an option or fitted to export models , but certainly I remember changing my 0356 cam as fitted for an 0357 in 1967.

A10 1956 valve clearance - a7a10.net

www.a7a10.net › fo
is worth looking at for it posts EDDIE DOWS tuning note for A!0 engines
 
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Jerry Doe

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Its nice to break away from the computer every so often and head in the garage. Yesterday I was able to install the swinging arm along with new bushes and shaft. It was not easy as these a10s have stupid swinging arm setup, but I did it!

I removed the rods and it seems like its on standard grind, but well pitted. So I will probably have to get it ground all the way. The rods are shot.

I really need to find someone locally who can do machine work on my cases (Denver). Jim doesn't do BSA's
I need a good chrome company and can ship. Seems there is no where near me. I called a place and they want $700 to plate my rear mud-guard/ Fender. Seems a lot.
 
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FROM Roy Bacon book:
A10 Super Rocket
1958-59: .008/.008 (67-356)
1960-63: .008/.010 (67-357 probably export only in 60-61, 67-356 for home, used for all from 62)

I have 4 BSA factory parts books circa 1949-53, 1954-57, 1958-59, 1960-63.
No notes for exceptions.... like "export only".
I accept the BSA book for 60-63 DA10R-101 on parts applications

I would like to see some authentic BSA literature saying they had home market versions.
 

Craig

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For any that may be looking for the red and gold “pear shaped BSA badges” , found them in Walridge flyer that landed in mailbox today (sale ends Feb 28/21) , Mike is selling pairs of them for $79.95 CAD , not sure if that a good price or not ... they are available ..... Also a few used steel Norton tanks that appear to be decent ....
 
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2 badges 14.95 GBP Armours 1991
2 badges 23.95 GBP Classic badges Redditch UK 2001
:)
 

texasSlick

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I need a good chrome company and can ship. Seems there is no where near me. I called a place and they want $700 to plate my rear mud-guard/ Fender. Seems a lot.

Quality chrome plating is expensive. The management and disposal of waste water and satisfying EPA adds 25 to 30% to the cost. Quality chrome is a three layer copper - nickel - chrome, with decent thicknesses of each.

I gave $300 US several years ago to chrome my primary cover. The cost is all related to the square inches. Do the math, relate the sq. Inches of your mudguard to an Atlas primary cover, that will give you an estimate of the fair cost of plating the mudguard. I would say $700 is in the ballpark.

North Texas Quality Chrome in Gainsville Texas did my primary cover and some other details.

Slick
 
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