A shameless image thread for the enginephiles

[Tommy Cookers]

it is a dyno fact in one plot that I linked during that 'discussion' (p 130-2 in 2 strokes thread) on port timing
http://www.rd350lc.net/CurveBad4L0.jpg
(btw these CW? Cycle Guide ? torque plots showed some British bikes as similarly patchy) - yours seems to be smoothed
we need in top gear enough WOT torque to 'overcome' drag including headwinds and motorway hills
the UK RD350'A' had 6th gear blanked off but the UK RD350B didn't (so I test-rode the A but bought a B)

anyway I'm now (after seeing others' posts) glad to have missed the rotary valve Kawasaki & Bridgestone (& the '350' Suzuki)
shame the UK didn't get the 305 (4 stroke) Kawasaki (till years later the GPZ 305)
and the Hondamatic 400 (28 bhp) at 1099 sterling just didn't sell - the conventional 6 speed (40 bhp) was 799 sterling
I offered 899 for the 'matic and was refused - later Honda cut the price to 699 and they all sold in days

btw another British radial valve engine was the BSA 250 single MC1 race prototype built in the 1950s but kept secret

[J.A.W.]

T-C, the dyno chart you presented - clearly indicates a carburettor/fuelling 'glitch' in the early RD350LC,
which was the cause of a 'dealer recall', for a jetting 'fix' - to be applied..

It was a fine-tuning issue, & by no means a fundamental characteristic - of a flawed engine design.

I'd suggest the riding problem you alluded to - is indicative of a failure to adapt riding style, from just rolling
a throttle open on a plodding dobbin 4T, to positively using the gearbox - on a spritely, spirited, pursang 2T..


The early `70s RD 350 - which you noted, did not show any such problem - in fact, it was a significant
advance over its essentially similiar R5C predecessor, by dint of reed-valves, disc brake & a 6th gear.

As for the BSA MC1... it Is yet another sorry example of British 'defeat - snatched from the jaws of victory'..


However, designer-engineer Doug Hele later used that stylish 'perimeter' frame in the F750 Tri/BSA 3's..

Yamaha also used the BSA's triangulated tube cantilever swingarm design in their RDLC,
& followed it up with - a very like full 'perimeter' loop frame - for the subsequent YPVS model.

[Powerslide]

Here's an image for you BT:

https://audimediacenter-a.akamaihd.net/ ... 1461574344

Reckon anyone in F1 do the same?

https://www.audiworld.com/news/04/a8tdi ... tdi-10.jpg

not good with electronics but i read it needs double the voltage of a normal car for them to run that electric supercharger?

[Big Tea]

T-C, the dyno chart you presented - clearly indicates a carburettor/fuelling 'glitch' in the early RD350LC,
which was the cause of a 'dealer recall', for a jetting 'fix' - to be applied..

It was a fine-tuning issue, & by no means a fundamental characteristic - of a flawed engine design.

I'd suggest the riding problem you alluded to - is indicative of a failure to adapt riding style, from just rolling
a throttle open on a plodding dobbin 4T, to positively using the gearbox - on a spritely, spirited, pursang 2T..


The early `70s RD 350 - which you noted, did not show any such problem - in fact, it was a significant
advance over its essentially similiar R5C predecessor, by dint of reed-valves, disc brake & a 6th gear.

As for the BSA MC1... it Is yet another sorry example of British 'defeat - snatched from the jaws of victory'..
http://www.bsmotoring.com/story_img/big ... 8B6456.jpg

However, designer-engineer Doug Hele later used that stylish 'perimeter' frame in the F750 Tri/BSA 3's..

Yamaha also used the BSA's triangulated tube cantilever swingarm design in their RDLC,
& followed it up with - a very like full 'perimeter' loop frame - for the subsequent YPVS model.

http://www.bellesbecanes.fr/media/yamah ... 042015.JPG

The BSA, is that a solid rear end? no suspension at all on a race bike?
Interesting front end too, reminds me of something that will not come to mind.
Gordon Blare was working on something similar with Seeley but with hub steering on a G50
Did a quick google but can not find it

[dren]

Here's an image for you BT:

https://audimediacenter-a.akamaihd.net/ ... 1461574344

Reckon anyone in F1 do the same?

https://www.audiworld.com/news/04/a8tdi ... tdi-10.jpg

not good with electronics but i read it needs double the voltage of a normal car for them to run that electric supercharger?

It should be 48v system.

[dren]

Here's an image for you BT:

https://audimediacenter-a.akamaihd.net/ ... 1461574344

Reckon anyone in F1 do the same?

https://www.audiworld.com/news/04/a8tdi ... tdi-10.jpg

An interesting idea to promote swirl but that could be done with cam timing. I'm not sure they would have a reason to switch between 1 and 2 valve mode. This intake works with the 'vtec' on exhaust that allows them to run on one or two turbos.

[Tommy Cookers]

the BSA MC1 front fork seems to be resemble the Earles type except that .....

Earles complete specification patent (application) filed in Dec 1951 refers to construction from tubes
(interestingly his provisional specification is for his well-known leading link type but also a similar trailing link type)
clearly the complete spec shows the leading link type made for MV via Les Graham and used in GP seasons 1952-3
the LG MV forks (and frame) were made from magnesium alloy
Vic Willoughby wrote that their geometry was dubious

so the BSA might appear to be outside the Earles patent

the BMW forks used in racing and production from 1955 - 1970 may have been within the Earles patent (was it granted ??)
see http:/bmwdean.com/earles-fork.htm

[Big Tea]

the BSA MC1 front fork seems to be resemble the Earles type except that .....

Earles complete specification patent (application) filed in Dec 1951 refers to construction from tubes
(interestingly his provisional specification is for his well-known leading link type but also a similar trailing link type)
clearly the complete spec shows the leading link type made for MV via Les Graham and used in GP seasons 1952-3
the LG MV forks (and frame) were made from magnesium alloy
Vic Willoughby wrote that their geometry was dubious

so the BSA might appear to be outside the Earles patent

the BMW forks used in racing and production from 1955 - 1970 may have been within the Earles patent (was it granted ??)
see http:/bmwdean.com/earles-fork.htm

Been stretching my brain (does not take much) and can not pin it down. I keep thinking of a race outfit (sidecar) but not sure. Been googling like mad

[J.A.W.]

Yamaha also used the BSA's triangulated tube cantilever swingarm design in their RDLC...

The BSA, is that a solid rear end? no suspension at all on a race bike?

Hardly likely, is it.. B-T.. &, as it happens.. there's another one.. the Brits had 'done earlier'*..



*Albeit, to be fair, this one is.. an Aussie new-build.. upgrade of an upgrade - 'grandad's axe' - example..

[Big Tea]

Yamaha also used the BSA's triangulated tube cantilever swingarm design in their RDLC...

The BSA, is that a solid rear end? no suspension at all on a race bike?

Hardly likely, is it.. B-T.. &, as it happens.. there's another one.. the Brits had 'done earlier'*..

https://eglivincent.files.wordpress.com ... ent-04.jpg

*Albeit, to be fair, this one is.. an Aussie new-build.. upgrade of an upgrade - 'grandad's axe' - example..

At least I can see the big ohlins damper in that one . did I miss it in the Beeza or is it really not there?

[J.A.W.]

Ok B-T, I think you'll just have to 'ask yourself'.. as the old saw goes..

But.. since the then mighty BSA/Triumph organisation.. did have their 'brilliant' sprung-hub.. available..

Triumph T100 G.P. racer - also appears rigid, but its not quite..

[J.A.W.]

Seems as if famed racer-fabricator Colin Seeley..
juat might've found something useful to emulate - in that wee BSA, too..

[Big Tea]

I think this may be the BSA above
https://www.motorcycleclassics.com/clas ... cz12ndzbea






248.5cc air-cooled DOHC horizontal single-cylinder with bevel-gear camshaft drive,
four radial valves and external flywheel,

[roon]

That bike has the same stance as the rider.

[Big Tea]

That bike has the same stance as the rider.

Would be 5mph quicker without the combined screen/number/airbrake on the headlight