[ST] high mileage sprint -- follow up

["pete licht" <aloishus@xxxxxxxxxxx>]

I posted earlier about the high leakdown of my 44k mile still-warrantied ST. 
  Since the subject of break-in has been raised:  I followed the factory 
break-in procedure and had the first service done at 630 miles.  Since then 
I have mostly been riding it "like I stole it."

Today the shop got into the engine and determined that all of the intake 
valves are severely worn, one of the exhaust valves is burnt; the 
rings/pistons/sleeves are all fine.  Triumph is paying for a valve job as 
well as the diagnostics.

I do not look forward to having to break in the engine again.

Pete
99ST


>
>Date: Sat, 01 Dec 2001 18:30:44 -0800
>From: Rich Hartwick <hartwick@xxxxxxx>
>Subject: [ST] Oil Consumption and Break-In
>
>I would agree with "Rick in Oregon" on the need for some strong use of the 
>engine to
>help seat the rings properly.  These are powerful engines, and it is hard 
>to strain
>them enough to get things properly seated.  The pressure of the rings on 
>the walls
>comes from "inflation" by the combustion gasses behind them, and not from 
>the
>springiness of the metal. It is important to have some full throttle 
>operations
>under load to generate high enough combustion chamber pressures to push the 
>rings
>agains the cylinder and break the oil film and glaze.  In the northeast US 
>here, it
>is easy, since we have so many hills.  On a new engine, I will run it in 
>normally,
>with increasing loads and short bursts of full throttle.  After the 500 
>mile
>breakin,  I find some long hills, and basically allow the motor to pull at 
>full
>throttle and high rpm for longer and longer periods.  Doing this 2-up is 
>even
>better.  With this procedure on both the Trophy and Sprint, I have had 
>motors with
>essentially 0 oil consumption.
>
>These motors need to do some work now and then.  Babying them is worse than 
>goosing
>them.  By far, the worst thing to do to any motor is lug it.  For the 
>Sprint, I
>consider anything below about 3,500-4,000 rpm under load, as lugging the 
>motor.
>Also, I could never understand criticisms of the Triumph motors as having a 
>flat
>spot at 3,500 rpm.  Who cares?  Nobody does any serious work there anyway, 
>and a
>flat spot there is almost meaningless, and I believe the EPA tests focus on
>emissions and noise near that rpm.  OTOH, I don't like redlining any motor 
>except
>very briefly and occasionally.  Lots of stresses generated at 10,000 rpm.  
>In my
>mind, these motors live in the 4-7,000 rpm range.
>
>Anyway, I am looking forward to putting 100,000 on this Sprint.  My Trophy 
>had
>30,000 when I traded it, and ran absolutely perfectly, and the Sprint is 
>doing just
>as well with only 12,000 miles this year.
>
>Rick Hartwick
>00 Sprint ST
>
>
>
> > From: "Rick & Joyce" <wescottr@xxxxxxxxxxxxx>
> > Subject: Re: [ST] high mileage sprints
> >
> > Likely the rings haven't properly seated, often the result of a
> > too-literal interpretation of the break-in sticker tying RPM to
> > distance travelled.
> >
> > In MY opinion:  (donning Nomex suit)
> > a) Triumph's break-in recommendations are too conservative.
> > After the first couple hundred miles and multiple heating/cooling
> > cycles, an engine should experience several full-throttle "pulls"
> > BEFORE the running-in oil is drained at the first service.
> > b) If you don't routinely "ride it like you stole it" or live in
> > a very hot climate, then it's more likely that the rings will
> > seat properly if full-synthetic oil is avoided until after 3K
> > miles.  Want more oil information?
>
>


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