[Shotimes] Re: help.....valve chatter and rod knock...

[Ron Porter]

I disagree, there are NOT that many rod bearing failures. There are many
cars running around with 200K+ miles on original bearings. FWIW, if bearings
wear out over 200K, that sounds like normal maintenance to me......

If someone buys a used SHO with a questionable service history, and it has
75K+ miles, I would change the rod bearings. Otherwise, for original-owner
cars, or well-maintained cars, I wouldn't worry about it.

Ron Porter

-----Original Message-----
From: shotimes-admin@autox.team.net
[mailto:shotimes-admin@autox.team.net]On Behalf Of David P
Sent: Sunday, October 27, 2002 9:51 AM
To: Erik Balser; shotimes@autox.team.net
Subject: Re: [Shotimes] Re: help.....valve chatter and rod knock...


    Rod bearing replacement should become part of the 60k service, or at
least by 100k. Main bearings should be done every other 60k, or 150k at the
most. Some motors may not need the bearings, but the motor needs the oil
pressure to maintain other things, like the valvetrain. I replaced my rods
and mains at 70k and gained 3-11psi depending on the rpm.

    All this talk of rod bearing failures (through the years) has me
wondering why there are so many. What I am questioning is whether or not the
journal places enough pressure on the bearings to keep them seated to a low
enough psi to be considered reliable. Maybe for Yamaha's engineers. Most of
the stuff Yamaha builds is high maintenance, low duty (racing motors,
motorcycles, boats, etc...).



David P

95MTX