From: davewi@soccer.wv.tek.com (David H. Wise)
Newsgroups: rec.motorcycles
Subject: Re: chain vs belt vs shaft drive
Date: 17 Apr 92 21:26:24 GMT
Reply-To: davewi@soccer.wv.tek.com
Organization: Tektronix, Inc., Wilsonville,  OR.

In article <1283@adpplz.UUCP> martin@adpgate.UUCP (Martin Golding) writes:
>davewi@soccer.wv.tek.com (David H. Wise) writes:
>
>: This would be absolutely true, except for one little detail that sinks it
>: completely: the pinion _can't_ climb the ring.  Reason: the final drive
>: assembly is rigid and holds all the pieces in a fixed relationship.  

The first email about this slip of the finger came in a few hours after
I posted it.  All I can say is that I've said wronger things, with
more conviction.  This little boo-boo is a pecadillo by comparison.

>My dear boy, you've been dismantling the wrong part of your motorcycle
>(although you should have gotten this one right, as you had your wife's
>rear end completely stripped not so long ago. Her Virago, I mean.)

[Two barbs in one sentence.  I think you took so long to reply
because you work hard to slip 'em all in.]

I take the fifth.  I wouldn't touch this one with a ten-foot pole.
And that is ONLY a metaphor :-) .

Oh, and the Virago is back to normal.  I had to _make_ my spacers though,
by drilling out and filing down a set of nuts.

There is no such thing as dismantling the wrong part of a motorcycle.
Sometimes one dismantles a part strictly for educational purposes :-) .

>Picture for a moment your CX500 squatting like a great lump on its stand.

I prefer to picture it shouting its way down an empty road at the DoD speed.

>Consider the shaft/wheel/tirepatch relationship: about 90 degrees, more
>or less. Now imagine the shaft rising as the tirepatch sits in one place.
>Behold: The pinion is several degrees further up the ring gear. The
>engine force has raised the shaft instead of moving the motorcycle forward.
>
>But that just confuses the picture. The engine force tries to rotate the
>shaft. The shaft tries to rotate the wheel. Anything that lets the wheel
>rotate will absorb the engine force; on any ordinary shaft bike the
>wheel can do a significant fraction of a revolution by just bending
>the motorcycle at the swingarm pivot (until spring force is too high or
>something jams). Since this requires less force than pushing that great
>fat watersloshing pintsized ... Sorry, didn't mean to get personal...
>motorcycle forward, the shaft rises before the motorcycle moves.

Ahem.  Some of us get attached to our bikes, even though they are
underpowered and overweight.  OTHERS buy bikes that make it halfway
home from the sale, and still profess to love them.  The world is full
of wierd people.  Some of them's us.

Packy has never, in his entire 20000-mile career with me, _broken_ down.
I have _taken_ him down a few times, mostly to improve things.  Some of
those improvement jobs kinda grew (right, Martin?), but that was my own
fault.

>: Now, can anyone explain how the paralever minimizes shaft jacking?
>
>Given the above simplification, certainly. The paralever suspension forces
>the wheel to move in a (more) vertical path; you can picture it as the axle
>being forced backward as the swingarm rises up. Thus the wheel doesn't
>rotate, so the shaft doesn't, so the engine force is expended moving that
>great wallowing pig^H^H^H^H^H^H^H^H the motorcycle forward instead of up.

"Wallowing pig", indeed.  Remember who was tight on your R100's tail the
whole way to the coast.  And back.  Packy keeps up just fine, thank you.
I remember how sorry I was for you, that you had to perch that lumbering
mass of R-bike on those teeny square tires.

>(If you go back to the pinion-climbs-the-ring-gear, the extra shaft
>rotates the housing down to compensate for shaft rise, so the 
>shaft/wheel/tirepatch angle remains closer to 90 degrees.)
>
>
>: David Wise (DoD#427, davewi@orca.wv.tek.com, Porky -- 1980 CX500C)

Keep it up, and I'll have to retaliate by buying an FJ.  Or maybe a
Ducati, so when I break down, I know I'll have company in a minute or two.
When you catch up.  Unless you break down first.  Although I could just
stop Packy by the side of the road and wait, and get the company anyway.
Nah.  There must be something to this Ducati stuff.  Gotta check it out.

>
>
>          Martin Golding             |  I have five motorcycles, 
>DoD #236  BMWMOA #55952  WMTC #0002  |   the brands are important to ME.
>[motcsd!]mcspdx!adpgate!martin       |    :-Pthpthpthpthpth!

						^^^
Which one is running today? --------------------|||
--

--
David Wise (DoD#427, davewi@orca.wv.tek.com, Packy -- 1980 CX500C)