Featherbed frame design went against all engineering princip

Chris · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

My friend sold his drainpipe to the National Motorcycle Museum.
One was raced by a member of the CRMC at our races.
Jamie Walters has one.
Whos got number 4?
There is a frame with pannier mounts/road brackets.
Paul said there was never a plan to do a road frame

Chris

ps my Dresda Dommie with straight upright with (as Ken says) No crack YET!

Featherbed frame design went against all engineering princip

74ok · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

thoughts on this frame?

grandpaul · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

84ok said:
thoughts on this frame?

Needs shocks.

acotrel · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

The Drainpipe Norton .

I like that near straight tube which goes from the steering head down to the pivot mount - that can only be good, the spine oil tank is ugly :

https://www.youtube.com/watch?v=QreNam7_wmY

74ok · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

i was wondering what you folks that understand this stuff thought,

off topic but was just curious

the pix shows a stock harley fxr frame that is considered ~ the best handling big twin street frame they ever made (had a ~ 10 year run),
https://www.google.ca/search?q=fxr&ie=u ... =fxr+frame

huge aftermarket and clones/copies options are out there
https://www.google.ca/search?q=fxr+fram ... d=0CCcQsAQ

bit of history
http://en.wikipedia.org/wiki/Harley-Dav ... uper_Glide

The FXR Super Glide II was introduced in 1982 and sold alongside the existing FX models. The FXR chassis was essentially an FLT Tour Glide chassis with lighter frame tubes and a more conventional design around the steering head.[10] As such, it offered a rubber-mounted engine and a five-speed transmission, as opposed to the solid mounting and four-speed transmission of the original FX chassis.[10]

The FXR range was expanded in 1983 by the introduction of the FXRT Sport Glide, a Super Glide variant with a fairing and saddlebags, and the FXRS Low Glide, which was the FXR equivalent of the FXSB Low Rider. Upon the discontinuation of the corresponding FX-based models, the FXR Super Glide II became the FXR Super Glide and the FXRS Low Glide became the FXRS Low Rider. The Wide Glide was discontinued because the FXR frame was not suitable for the wide forks.[10]

The 1984 Disc Glide as it was known was a very rare motorcycle it had the first offering of the "Chrome Package" meaning it came with chrome rocker boxes, nose cone, and primary cover. It was called the FXRSDG.[citation needed]

http://www.motorcyclespecs.co.za/model/ ... _glide.htm

The FXRT's steel-tube frame has a mammoth, welded-up backbone, with deep, double downtubes and a square-steel swing arm. It's a fairly common design, very strong and very roomy—exactly why Harley adopted it last year for the R-family. The frame leaves plenty of room under the seat for the easily serviced battery, oil tank and rear suspension air coupling. The 64.7-in. wheel-base and 32° steering rake contribute to excellent straight-ahead stability. Still, the FXRT is reasonably nimble on the corners. The weight of the narrow, short V-Twin is concentrated low and in the middle of the bike; consequently, only moderate effort is required to lean the FXRT through most turns. Ridden on sun-baked pavement or rain-slick tarmac, pointed straight ahead or flicked back and forth through backroad turns, the Harley always feels stable. The narrowness of the engine, the high-mounted pegs and the 6-in. of ground clearance lets the rider really exercise the edges of the Dunlop K291 Touring Elites (19-in. front, 16-in. rear, mounted on nine-spoke cast aluminum wheels). At angles that would have many touring bikes scraping and sparking, the FXRT just floats around corners.

http://www.cvoharley.com/smf/index.php?topic=25417.0

“Team FXR” designed the new frame for maximum stiffness. Like the FLT frame, the new frame’s backbone was comprised of two-inch boxed tubular steel with massive stampings to add strength creating a large box-section that linked the steering head to a triangulated rear section and used round tubing at all points where the frame showed. To make the new frame even stiffer than the FLT’s the engineers added more gusseting between the steering head and both the backbone and down tubes. In the end, it was claimed to be 5 times stiffer than the old FX frame, yet added nothing in weight.

this part is for hobot, somewhat related

The new frame of the FLT was the first to use the “exclusive” Harley-Davidson Tri-mount chassis with the three-point maintenance-free automotive type elastomer engine mounted system

Hobot · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

Seeley spinal version

sheet aluminum boxy kind

Rohan · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

That looks like a good design.
Bet if someone built them, they would sell like hotcakes....

hobot said:

wakeup · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

hobot said:
sheet aluminum boxy kind

I thought the monocoque JPNs were either stainless or mild steel?
cheers
wakeup

Hobot · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

Its the sexy-est looker to me. I'm hoping with the isolastic overlapping rubber dampened back up of Peel's tri-links she can take the power loads on and off road and not crack though jumping off high enough stuff may, so for that use she'd have the triple triangulated exterior crash braces installed.

pommie john · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

wakeup said:
hobot said:

sheet aluminum boxy kind

Click to expand...

I thought the monocoque JPNs were either stainless or mild steel?
cheers
wakeup

Yeah, they were stainless, not sure why though.

lcrken · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

wakeup said:
hobot said:

sheet aluminum boxy kind

Click to expand...

I thought the monocoque JPNs were either stainless or mild steel?
cheers
wakeup

And you were correct.

The one in hobot's post is stainless steel.

Ken

Rohan · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

pommie john said:
Yeah, they were stainless, not sure why though.

To make it heavy, hard to work and expensive to make ??
Won't rust though.....

Note that that is before someone cut holes in it - to make it possible to change the plugs.
Without dropping the engine out....

They built it first, and designed it later ??

pommie john · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

Rohan said:
pommie john said:

Yeah, they were stainless, not sure why though.

Click to expand...

To make it heavy, hard to work and expensive to make ??
Won't rust though.....

Note that that is before someone cut holes in it - to make it possible to change the plugs.
Without dropping the engine out....

They built it first, and designed it later ??

LOL. Yep. That must be it... they succeeded in those aims.

Hobot · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

I found the photo in google images with Aluminium label but just now followed it to source URL page to find it was an accessnort thread titled Aluminum frame as was photo, sorry.

Cd's bent tubes can have some desirable flex tolerance compliance. All's I know is I can't get No Satisfaction on others for addicting multiple hammer head groin spikes corner orgasms Peel delivered on endro tires aired almost 60 PSI, just got better-easier by letting isolastic frame and Roadholders do their thing more purely perfectly. If you've never air'd up over 50 PSI on good surfaces on good unlinked Commando Oh LA LA, real flying carpet sense as iso have firmer countering reaction force that allows wonderful isolation but the vital road texture. For me Peel has solved=satisfied a. the compliance 'sideways suspension' mystery and where is should occur from tire force-vectors conflicting with desired aim, b. energy storage w/o extra pilot effort for controlled release in 3 ways >>> over time >> what direction and how intense>, c. transparency to outside influences, wind gusts to ruts that pass through distinctly like waves through a flag but it don't bother the flags firm anchor nor ability to pivot in place freely. Peel feels and gets as animated under me as the knees of mogul slalom skier. Words fail to convey how Flabbergastingly Fabulous Uncanny a Commando is to me.

Aluminum tube and cast pyramids & arches of my stiff corner cripple.

acotrel · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

Rohan said:
pommie john said:

Yeah, they were stainless, not sure why though.

Click to expand...

To make it heavy, hard to work and expensive to make ??
Won't rust though.....

Note that that is before someone cut holes in it - to make it possible to change the plugs.
Without dropping the engine out....

They built it first, and designed it later ??

How do you weld a stainless steel frame and get the metallurgy right ? Even making a chrome-moly frame is not easy, - if you steel-weld it, you are probably obliged to stress relieve it in the jig. If you bronze weld it, that brings other problems. The monocoque looks good, however attaching the swing arm so that it stays related to the steering head seems all too difficult to me. I really like that aircraft construction which uses aluminium honeycomb bonded between sheets of aluminium. We used to do that when I worked at Government Aircraft Factories. That was before the bonding facility got sold off to Boeing.

Rohan · Oct 12, 2014

Re: Featherbed frame design went against all engineering pri

acotrel said:
How do you weld a stainless steel frame and get the metallurgy right ?

You stainless weld it in argon.
Probably need to be annealed a few times along the way though.

This is not exactly new technology.
Lawrence of Arabia is reputed to have specified stainless tanks for his BroughSuperiors.
circa 1920s....

http://i.dailymail.co.uk/i/pix/2012/10/ ... 38x490.jpg

plebs had to make do with nickel-plated mild steel.
You'd need x-ray vision to spot the difference ??

But we diverge from JPN monocoque frames.
Wonder why they didn't just use mild steel ??

worntorn · Oct 13, 2014

Re: Featherbed frame design went against all engineering pri

Stainless tig welds very nicely, nicer than mild steel. It is not heavy, my Egli frame weighs 22 pounds including the oil tank and very sturdy mono-shock swing arm.
And it is very stiff. The effort required to bend 1" x. 065 304 stainless tubing in a pipe bender is approximately four times the effort required to bend the same dimension mild steel tubing.
It is a lot of extra work to deal with thermal shifting during welding. I felt the extra work was well worthwhile when cleaning the bike this spring. The alloy rims suffered pitting from road salt while the stainless steel frame still looks as new after a running a cloth over it.

Not sure if Norton was concerned about corrosion with a race bike, however.

Glen

acotrel · Oct 13, 2014

Re: Featherbed frame design went against all engineering pri

worntorn said:
Stainless tig welds very nicely, nicer than mild steel. It is not heavy, my Egli frame weighs 22 pounds including the oil tank and very sturdy mono-shock swing arm.
And it is very stiff. The effort required to bend 1" x. 065 304 stainless tubing in a pipe bender is approximately four times the effort required to bend the same dimension mild steel tubing.
It is a lot of extra work to deal with thermal shifting during welding. I felt the extra work was well worthwhile when cleaning the bike this spring. The alloy rims suffered pitting from road salt while the stainless steel frame still looks as new after a running a cloth over it.

Not sure if Norton was concerned about corrosion with a race bike, however.

Glen

I thought that 18/8 stainless is austenitic and that physical properties after welding steel depends on the ratio of austenite to martensite. Is stainless steel OK for frames ? Has anyone ever ridden one to destruction ?

Rohan · Oct 13, 2014

Re: Featherbed frame design went against all engineering pri

acotrel said:
Has anyone ever ridden one to destruction ?

Didn't 'Crasher White' cartwheel one of the JPN monocoques off the track (Brands ?),
and someone commented that something that took months to build was reduced to a lampstand in seconds.

But thats not maybe what you mean by 'destruction' ? !

BTW, that lampstand was recently ressurected back into a bike, after the fire in the NMCM reduced the others to ashes ?

nickguzzi · Oct 13, 2014

Re: Featherbed frame design went against all engineering pri

"Stainless Steel" is about as generic as "sweets" or "candy" for the USians.
Without a grade or spec, discussion on welding is moot.