Engine breaking in

Grant said:
When I run in a new Laverda engine I take it steady but am more concerned with not putting the engine under big load for a few hundred miles rather than obsess about a rev limit.
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Number one concern with a break in is not loading the engine especially at low revs. ....... and as Steve quoted some of the Lycoming site then there is not a lot I can say.

I have broken in a couple of aero engines and the technique for the first two flights was using mineral oil ..... a very slow application of power but then a full power climb to about 6000 feet ....... then ease back the power so as not to shock cool (mainly an aero thing) and descend as low as possible then full power again up to 6000 again then come in and land. Then check the magnetic plug for chips and change the filter. Then add the same oil and go fly at high power settings for the next 10 hours of flight ...... then change the oil and she is broke in!

The directions from Moto Guzzi for my MGS-01 were to break in the bike by riding on a track and using all the revs available but not to use full throttle for the first 5 kms. Then 5 kms of full power and then change the oil. Then she is broke in! If track not available then a dyno is recommended for break in.
 
We're all pretty much on the same page. But running in on a dyno is something I would not do unless it was a programmable load type - and those are rare now, most being inertia type.

I have actually used a hydraulic direct coupled to the hub type which was fully programmable. Dynapac 2000 - NZ made too.
For a straight acceleration run we programmed it to hold load every 250rpm until stable then advance rpm to a fixed figure which it would not exceed. Just for fun as it was a speedway car - bike engined - we set it up to do laps on a 1/4 mile and were able to sort the best gearing to suit the power curve. Most interesting.
 
Grant said:
so it would be pointless comparing automotive engines to ours.
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Same dog, different leg. Just a piston and rings going up and down in a cylinder searching for the same end point, ie the correct bedding in of the rings.
 
This is a minefield, with perhaps dozens of 'correct' answers.

I did find this interesting article that advocates both scenarios to a certain extent (break in slowly or thrash it):
https://www.2addicts.com/forums/showthread.php?t=1128783

I believe my new car engine was run in at the factory. According to the salesman the engines are run hard for a short period with lots of gizmos analysing heat balance etc. I was advised that no special provisions are necessary for me at all after delivery,  just use it normally with a synthetic oil change at the first 10,000 miles.

I did run in my Yamaha RD250 air-cooled as per the book and it was a bit slow. My mate thrashed his Suzuki X7 from new and that thing was a flier!
 
Davo said:
Same dog, different leg. Just a piston and rings going up and down in a cylinder searching for the same end point, ie the correct bedding in of the rings.
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I don't think so.
Water-cooled engines run tighter tolerances than air-cooled engines.
Looking at water-cooled engine bores they seem more finely honed than air-cooled, from the limited number I have seen.
I have no idea if piston and/or ring metallurgy or technology is different too.
 
There will be many scenarii and I'm convinced that the running in of a race
or tourism engine are different. After all, a well built race engine must break on the finish line.

When Gijs van Dijck handed me my rebuilt TT2 engine, it was: 4000 revs for 500 km, then progressively from there.

Paul
 
I wont be able to run in the motor under load until I get the timing and carbs dialed in, and that means running the motor up and down the revs without load for a while until we get the jetting right. I hope this wont be the time we get any glazing so I should probably make sure we let the lump stay cool while doing this. Any other thoughts as this process involves some stalling, quick rev changes up and down, and varying idle ranges.
 
You may find that jetting works best when determining mixture under load as well as very little load .......... just don't give too much throttle at low revs ..... but the higher the revs .... the harder you can run her ..... and it's all good.
 
why re invent the wheel just do what moto laverda advised in there operation and maintenance book, which was probaly porn 40years ago so go steady when you open her up :P
regards andy 
 
helicopterjim said:
... slow application of power but then a full power climb to about 6000 feet .......
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Does that mean we'll have to strap a set of wings onto our bikes to run them in?

Running in an air cooled engine on a dyno can risk overheating, which is not a good thing. 

Unless your dyno is in a wind tunnel it'll never have a supply of cooling air anything like what you get when travelling at speed out on the road.
 
Dellortoman said:
Does that mean we'll have to strap a set of wings onto our bikes to run them in?

Running in an air cooled engine on a dyno can risk overheating, which is not a good thing. 

Unless your dyno is in a wind tunnel it'll never have a supply of cooling air anything like what you get when travelling at speed out on the road.
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Agreed ..... my friends dyno has a large fan but he will only do 3 runs max before shutting down for a cool off period.
 
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