Running in new engine techniques

[bwringer]

I'd ask the guy who built the engine, but it sounds like he might not be available...?

For me, it's more about managing the risks of part failures or assembly errors. A slightly different set of priorities than they had back in disco era Hamamatsu.

Out of something akin to paranoia, I usually change the oil at about 50 miles just to look for excessive sparklies and chunks (some sparklies and bits on the drain plug magnet are perfectly normal, of course). Then do the next at around 500 miles, then oil changes as normal after that.

And yes, ordinary riding and heat cycling, load and unload the rings, don't lug it. A varied and healthy diet of load and RPM. Maybe avoid hours of droning at the same RPM, so maybe don't set off on an Iron Butt ride right away. Check the oil frequently in case it's using more oil than expected, or springs a leak. I don't know that I'd spin a fresh build to redline right away, but once you've done that first oil change and all seems well, zing away.

The sticker the Suzuki factory placed on the tach advised avoiding redline for the first 600 miles. I don't think that level of restraint is really necessary. And the speed/RPM shift points given in the manual are ridiculously low, so ignore that.

[ukjules]

OK . 20m done as per method.
No leaks whatsoever.
Thanks for answers.
(now I gota fix my original engine
that compared to this one has been butchered.)

[Rob S.]

Just as in normal (post-breakin) running, lugging will likely do more harm than over revving.

The absolute safest breakin? According to the owner's manual. Here's Cycle World's reasoning:

New motorcycles are under warranty. The owner's manual instructions will result in the fewest warranty-covered repairs.

[Nessism]

Cycle World's test was for a brand new engine. Not a used engine where someone lapped the valves and honed a used cylinder. For that some additional cylinder pressure helps the ring seal.

[GS1150Pilot]

This is a good video:

[ukjules]

Tis fascinating .
I am going for the mid way .... basically what said on here.
assertive town driving style after engine warm.
engine braking and not being sluggish on engine.
and gradually building up.

[I must do a compression test tomorrow for analysis)

be good to compare to my old engine test )

Dont think there is anything terrible wrong with it
bar a lack of care (due to time) when doing a previous
top end rebuild ... stripped threads , gaskets in poor state
and I recall lapping valves myself .
but it worked and works now ! just had an oil leak.

[Rob S.]

Interesting. Like he said, improved metallurgy. Also like he said, it wasn't tested on a high performance engine.

Question: Are new rings, even pistons considered a 'top end' job?

[ukjules]

70 miles and 3 heat cycles running it in done.
(wet and cold here in uk now!)
Used method on here (assertive town riding and engine breaking)
Will gradually increase from now and chuck oil
at 500m and check valves and re torque.

no issues, no leaks , re torqued head to spec.
More power than old engine.

[over xmas I'll pull to bits the old engine
but take readings as I do , as I wanna know
what is wrong with it] look forward to that as
xmas reading.

[GS1150Pilot]

Very cool, Jules. I like your attitude.

[ukjules]

No need for books to read or films to watch over xmas period
as daily there will be updates on the old engine
renovation ... by someone who has never split
a crankcase before.

I can barely wait to start the novel .

I can foretell it will be rings , gaskets
and poss stripped threads not allowing
correct torque.
the main issue top end.
I refuse to believe I ballsed up the valves .