It can't be the journal diameter that makes the Triumph rods expensive, it's
got to be the width. They are not particularly large diameter bearings,
they're just very wide.
There's a lot of ways to fit a narrower rod, including aluminum or steel
spacers. They could be split and screwed or they could be wound on. They
don't need to be much or they can be done away with completely since the rod
can be located by the piston with thrust washers on the gudgeon pin rather
than by the edges of the crank journal--that's a better way anyway. Many
high rpm motors use that approach.
The biggest problem in all of this is that someone has to be the guinea pig.
Any solution tends to surface at least two new problems
-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net] On Behalf
Of Jack W. Drews
Sent: Thursday, August 26, 2004 3:52 PM
To: mordy dunst/ gasket works; fot@autox.team.net
Subject: Re: bearing width
I would not be nearly as interested in potential hp gain or ability to rev.
What I'm interested in is making available to the Triumph community some
high quality rods at a fraction of the cost of Carillos.
At 10:01 AM 8/26/2004, mordy dunst/ gasket works wrote:
>Granted, the TR tractor motor has a stout three main crank.. it's ability
to
>tolorate what we through at it is really amazing. But, the key here is
>three mains. I am not convinced that decreasing the rod jo diam is a
>good thing. It would seem that the advantage is reduced bearing speed
>but, disadvantage in increasing the unit bearing load? So, if our
>cranks are made with smaller rod journals will this be a problem in
>three Main cranks? -especially with flex harmonics?.
>
>But, if the bottom end of the rod is narrowed the crank journal would
>either have to be welded up or spaced would this then distribute the
>load and mitigate against this increased load?
>
>
>
>M. Dunst
uncle jack
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