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45 project bikes

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dalaymond

Posts: 304

Joined: Mon Oct 25, 2004 12:01 am

Location: Jonesville, Louisiana, USA

Post Tue Oct 12, 2010 12:30 pm

Re: 45 project bikes

Gonna be a cool looking scoot.
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irishbaker

Posts: 168

Joined: Sat Jul 26, 2008 2:59 pm

Location: Cork ,Republic of Ireland

Post Tue Oct 12, 2010 4:32 pm

Re: 45 project bikes

Ben nice motor!

did all BSA's have their rear brake/pedal mounted on the Left side?
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jib

Posts: 572

Joined: Sat Dec 10, 2005 3:36 pm

Location: devon,england

Post Tue Oct 12, 2010 4:58 pm

Re: 45 project bikes

only before they changed them to the right :D :D :D how facetious of me,sorry steve couldnt help myself...
but yes the early ones did, i think all the preunit ones were and probably into the late 60's early seventies.
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Tue Oct 12, 2010 11:04 pm

Re: 45 project bikes

very early foot-pedal layout was typically to have a right-footbrake, because the practice of taking the drive from the left side of the engine was almost universal from a very early stage. The general standardisation of left-side primary drive chains in the 1920s led to right-side footbrakes becoming common, although not universal, partly because drum brakes were becoming the norm and these were typically fitted on the opposite side to the drive sprocket which was normally on the same side as the primary drive ( the cross-over drive on a Harley 45 and Sportster is plain bad engineering and very much an anomaly in the wider world ).

The general introduction of positive-stop mechanisms in the UK and Europe meant that the gearchange was typically accomodated within a revised gearbox casting on the 'free' end of the gearbox ie the right, with left-side footbrakes being the norm as a result. The general introduction of integrated brake drum/sprocket castings meant that the left-foot footbrake was more logical anyway.

BSA actually swam against the tide rather here, because their small rigid-framed machines kept their pre-war style rear wheels for a long time, with resulting cross-over shafts for the rear brake mechanism. Even the pre-unit swinging-arm frames ( such as the A10 and B31 models ) had this feature, although not the rigid-frame heavyweight sidevalves like the M20.

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Shoot, a man could have a good weekend in Dallas with all that stuff...
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Tue Oct 12, 2010 11:15 pm

Re: 45 project bikes

European machines tended to have certain design trends such as flat-twin engines with in-line car-type gearboxes and small unit-construction two-strokes with engine-speed clutches and kickstarts and gearchanges on concentric shafts

H-Ds heavyweight non-unit gearbox with the clutch and gearchange operating mechanisms entering from the top is again, very much an anomaly.

Unit-construction British machines were typically a re-hash of pre-unit engineering designs, so the right-side gearchange stayed. The Sportster acquired a right-side change to compete with the British machines of the day. The very last versions of the British twin and three-cylinder machines acquired internal cross-over shafts to provide US-style foot-pedal layout for marketing reasons, as did the the Sporty which still has it.

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Last edited by 45Brit on Sat Oct 16, 2010 7:49 am, edited 1 time in total.
Shoot, a man could have a good weekend in Dallas with all that stuff...
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Tue Oct 12, 2010 11:24 pm

Re: 45 project bikes

So, virtually all British machines since the late 1930s to the mid-1970s have left side footbrakes.

Japanese machines of the post-war era were derived from a mixture of imported European ( mainly German ) practice, with a strong influence from car practice and the opportunity to do a basic rethink on a clean drawing-board. Japanese also drive on the left. Hence the general emergence from the beginning, of the generic Japanese format of the horizontally-split crankcase with the gearchange shaft across the front of the mechanism, brought out the left side for various reasons ( although you can go either side quite easily with a design of that sort ). Japanese kickstarts were and are, mainly on the right side. Likewise a horizontally-split crankcase makes it easier to have a chain-driven sohc or dohc engine than pushrods.
Shoot, a man could have a good weekend in Dallas with all that stuff...
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Piet Jan

User avatar

Posts: 48

Joined: Mon May 21, 2007 7:26 am

Post Fri Oct 15, 2010 1:50 am

Re: 45 project bikes

45Brit: ...and Europeans drive on the left...


Hello 45Brit, it seems you've never left the British isles! Everybody in the rest of Europe drives on the right side of the road (and I mean the right right side). So, if you ever go there please don't drive on the left side, as that will end in tears for sure :-)

PJ
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irishbaker

Posts: 168

Joined: Sat Jul 26, 2008 2:59 pm

Location: Cork ,Republic of Ireland

Post Fri Oct 15, 2010 2:36 am

Re: 45 project bikes

We're on the left side in Ireland too - seems some also like the right side here when it suits them :shock: :mrgreen:
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Sat Oct 16, 2010 7:48 am

Re: 45 project bikes

Piet Jan wrote:
45Brit: ...and Europeans drive on the left...


Hello 45Brit, it seems you've never left the British isles! Everybody in the rest of Europe drives on the right side of the road (and I mean the right right side). So, if you ever go there please don't drive on the left side, as that will end in tears for sure :-)

PJ


yes, lost the thread a bit there.... I have to admit that like a lot of people in the oil industry, for me Europe is a blank on the map containing Charles de Gaulle and Schiphol airports, the first seemingly constructed so that everywhere is as far as possible from everywhere else, and the latter apparently designed to send you through passport control at least twice between any two gates!
Shoot, a man could have a good weekend in Dallas with all that stuff...
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rd.king

Posts: 54

Joined: Sun Jan 08, 2006 8:31 am

Location: Ontario, Canada

Post Sun Oct 17, 2010 4:07 pm

Re: 45 project bikes

Just had to question this
H-Ds heavyweight non-unit gearbox with the clutch and gearchange operating mechanisms entering from the top is again, very much an anomaly.

I don't believe you can call 100 years of consistent practice an anomaly :D
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Tue Oct 19, 2010 1:29 am

Re: 45 project bikes

it's anomalous in the sense of being a departure from practice elsewhere. It's essentially a car-style selector mechanism using a bolted-on selector mechanism actuating a cam drum, as opposed to the "rotating shaft within the selector forks" or "ratchet-actuated cam plate" type mechanisms more common on motorcycle gearboxes of the period.

you could say the same about the panhead's bolted-up rocker pedestals and hydraulic tappets, straighforward car engineering of the time as opposed to the knucklehead's conventional motorcycle-style design which is pretty much the same as the then very popular JAP units.

"anomalous" doesn't mean "short-lived", nor does it mean "unique", although it often applies to things which are either or both.
Shoot, a man could have a good weekend in Dallas with all that stuff...
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rd.king

Posts: 54

Joined: Sun Jan 08, 2006 8:31 am

Location: Ontario, Canada

Post Tue Oct 19, 2010 3:34 pm

Re: 45 project bikes

I think You have missed my point.
Harley Davidson chose to develope their gearbox this way
and stuck with it up to the present.
it's anomalous in the sense of being a departure from practice elsewhere.

It's hard to follow the lead of others in an industry when your the leader. :D
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Wed Oct 20, 2010 7:03 am

Re: 45 project bikes

no, your point is covered.

"Anomalous" doesn't mean unique, superior, obsolete or irrelevant, or any one of a number of another terms it is commonly equated with. It simply means "different from the norm" The current separate gearbox is anomalous because it is the only such unit still in production. It was anomalous when it appeared because the top-mounted, detachable selectors and flat mounting plate were , and still are, rare if not unique.

I would say it would be difficult to justify either feature as particularly superior in engineering terms

The Sportster is a much more conventional design and has neither feature. The 45 is anomalous in having the input and output shafts at opposite ends, but its suspended mountings are conventional in the sense that they resemble the pattern used, for example, by the Sturmey-Archer gearboxes which were widely used when the design was first introduced.

I'd say the idea that H-D is, or ever was, an industry design leader was subject to the obvious caveat that others have long since ceased to follow. The original style bottom-link forks were widely licenced under the 'Castle' brand name, but the VL and subsequent springers are unique apart from oriental copies of the complete machine built ( pre-war ) under licence. The Sportster is an obvious attempt to copy British practice of the day. The practice of having one cam per valve was usual on side-valve engines everywhere, and grouping them together on a single shaft ( as on the knucklehead and subsequent ohv big twins ) was already being done by engine manufacturers such as JAP and Motosacoche.
Shoot, a man could have a good weekend in Dallas with all that stuff...
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rd.king

Posts: 54

Joined: Sun Jan 08, 2006 8:31 am

Location: Ontario, Canada

Post Wed Oct 20, 2010 4:55 pm

Re: 45 project bikes

Once again you missed the point
:D Humor :D
I think I'll avoid it in the future.

And the Knucklehead was developed from radial engine designs of the time
and had little to do with what J.A.prestwich & co. where doing.
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Wed Oct 27, 2010 12:34 pm

Re: 45 project bikes

If you look at the various details of the rocker gear design of the knucklehead you will find it is very similar to what JAP were doing with their racing engines in the late 30s - the cast pillars for the rocker arms and separate built-up, cast aluminium valve enclosures in particular. The single-shaft cam design is similar, although the use of angled followers is not.

JAP experimented with a vacuum-driven oil return from the rockers, but did not pursue it as their racing engines were by that time almost exclusively used for track racing where total loss lubrication remained in use till the 1970s, outliving JAP altogether. The oil nominally returned down the pushrod tubes although in practice much of it simply leaked out.

BSA had an internal throttle design in the 1930s, brought in as a styling feature in conjunction with discontinuation of the older 'inverted' style of clutch and brake levers
Shoot, a man could have a good weekend in Dallas with all that stuff...
<<

jib

Posts: 572

Joined: Sat Dec 10, 2005 3:36 pm

Location: devon,england

Post Wed Oct 27, 2010 2:50 pm

Re: 45 project bikes

hi ben ,not wanting to get involved with this at all,(but i just cant resist :lol: :lol: :lol: ) harley released the el in 36.. that means at least one years farting about in the shed of wackyness before it was rolled out. so it doesnt really equate to anything j.a.p were doing a couple of years later. :wink:
unless of course j.a.p racing engine were copied from harley el's. :shock:

will say though those sportster forks and brakes were very like the triumph ones of the same era :lol: :lol: :lol:
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years
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45Brit

Posts: 1416

Joined: Tue Nov 27, 2007 2:29 am

Post Thu Oct 28, 2010 1:35 pm

Re: 45 project bikes

I don't believe there was any relation at all between JAP and H-D, except that various parallel trends could be seen in several countries around that time.
Shoot, a man could have a good weekend in Dallas with all that stuff...
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Pa

Site Admin

Posts: 4715

Joined: Sun Mar 12, 2000 1:01 am

Location: Ohio USA

Post Thu Oct 28, 2010 4:14 pm

Re: 45 project bikes

Odd you fellas don't consider how folks, at times, invent the same ideas at the same time or in the same period. This has occured numerous times throughout history. People often plan inprovements over existing inventions. Gee ??? How can I make this better ? Pa
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George Greer

User avatar

Posts: 961

Joined: Wed Aug 28, 2002 12:01 am

Location: Markt Einersheim, Germany

Post Thu Oct 28, 2010 8:38 pm

Re: 45 project bikes

Pa...

I wish sometimes that aircraft engineers thought that way..

But most times, it is how can I make this more difficult to remove once installed.

George
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Pa

Site Admin

Posts: 4715

Joined: Sun Mar 12, 2000 1:01 am

Location: Ohio USA

Post Thu Oct 28, 2010 8:47 pm

Re: 45 project bikes

George Greer wrote:Pa...

I wish sometimes that aircraft engineers thought that way..

But most times, it is how can I make this more difficult to remove once installed.

George


I hear you George. Look at todays automobiles. Vans are even worse. I junked a van even though I had a replacement engine for it. After learning to how replace it, the bone yard got it. The whole front suspension, axle, steering components, frame cross member, and all the polution control goodies had to come out first. To top that off, the van had to be suspened high enough to drop the engine out from underneath. I'd say the engine when into the rolling chassis before the body went onto it.
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