From: alanf@eng.tridom.com (Alan Fleming)
Newsgroups: rec.motorcycles
Subject: Re: How to break-in new rings?
Date: 7 Oct 92 19:31:26 GMT
Reply-To: alanf@eng.tridom.com (Alan Fleming)
Followup-To: rec.motorcycles
Organization: AT&T Tridom; Marietta, Georgia

The following is an excerpt from a Feb 1991 article in Motorcyclist concerning
"Give it a Break-In"...breaking in that new motorcycle.  I'll repeat the parts
concerning proper break-in of new rings.  For more information, get the
magazine form Motorcyclist or your friendly library.

...Realize that an all-new or newly rebuilt engine has oil only in the sump and
none in the top end, filter and circulation system.  This means that during
those initial crank revolutions many of the bearing surfaces are metal to metal
until the oil reaches them, causing extreme wear and possible damage.  Leonard
[Jim Leonard, Vance & Hine's chief mechanic] suggests pulling the spark plugs
(to reduce compression resistance) and pushing the bike around in second gear
to circulate the oil under no engine load and bring the oil pressure up.  A
high-quality petroleum based oil (low-viscosity Valvoline 30-weight was a 
popular choice) should be used.  Synthetic oil lubricates too well to allow the
rings to seat in properly, and according to the information we received, if 
it's used during intial breakin, the rings are sure to glaze.  Since heat
builds rapidly, our experts suggest that the initial run be limited to bringing
the engine up to temperature (both oil and coolant) with little or no load,
then shutting it down to cool off and checking for coolant and oil leaks.  Such
precautions may seem unnecessary with a new bike, but more than one of our
experts said otherwise.  (Of course, it's likely that a new bike was run at the
factory and ridden by the dealer's service techs during setup, so the new bike
buyer may reasonably skip this step.)
   After a through cool down (ideally back down to ambient temperature) and
throughly check[ed] for leaks, start the engine and ride it under light loads
at relatively low rpm; from 3000 to 5000 rpm is suggested.  Nigel Patrick of
Patrick Racing cautions against getting into top gear too early at this point
in the break-in.  Since the rpm should be kept low, using top gear is tempting
in order to get up to speed, but according to Patrick, lugging the engine is
more detrimental than high rpm, so resist the temptation to use top gear.  One
key piece of advice is to constantly vary the load on the engine, a constant
load is not ideal for breaking in the bearing tolerances.  This run should last
only 10 to 15 minutes before another complete cool down.  In other words, take
it easy on the ride home.
   The next run shojld be at slightly higher rpm, 5000 to 7000, and under light
to medium loads using short bursts of acceleration to seat the rings in early.
Again, 10 to 15 minutes ofrunnning should do it, and continue to avoid top
gear.  The third run should consist of light to medium engine loads with a few
more bursts of medium-high rpm, 8000 to 9000 rpm maximum,and last just 10 to
15 minutes, varying the engine load and avoiding top gear.
   Next, while the engine is still warm, drain the oil and change the filter.
Why so early?  Well, remember all those peaks and valleys throughout the engine
that we're carefully wearing away?  All of those tiny metal particles and any
stubborn metal shavings left over from manufacturing are now floating around in
the oil and not helping its ability to reduce friction.  Draining the oil while
warm may feel uncomfortable to the fingers unscrewing the drain plug, but it
helps get more ofthe oil out and in less time.  Vance & Hines' Al Ludington,
who with the riding talent of David Sadowski earned the '90 AMA 600 Supersport
title, feels that most of the metal particles that break loose will do so in
the first 50 to 75 miles and suggests getting them out quickly thereafter.
To ensure that the rings seat well, it's probably best to replace the oil with
the same high-quality petroleum based oil used initially, and don't be shy
about short-duration, high-rpm blasts through the lower gears after the oil
is changed.
  A few more 15 to 20 minute sessions should be used to work up to the engine's
redline, gradually increasing the engine loads.  After some definite hard
running and 250 to 500 miles total, it's a good idea to check the valves.
[reasons and methods deleted...this is too long already!]  After 500 miles
Patrick suggests retorquing the head.  [more deleted].  The switch to a 
synthetic oil was suggested by most of our master mechanics, but only after
500 to 1500 miles onn a petroleum based oil.
  Most of our experts warned of the danger of breaking in the engine too easily
and consequently ending up with an engine that will always run slow whether it
be from tight tolerances, inadequate ring seal or carbon buildup.  Engine load
is more detrimental than rpm, so avoid lugging the engine but rev it freely
especially in the lower gears.

[The above advice is not to be taken as the final word, just some tips from 
folks who have logged hours rebuilding engines.  If it helps, good, if not just
file it whereever you find appropriate.  I make no claims about the 
effectiveness of any of the above.]

Think Peace.
-- Alan (alanf@eng.tridom.com)
KotBBBB (1988 GSXR1100J)  AMA# 634578  DOD# 4210