Hard engine breakin

[Ridefree]

Hi all,
I have just had my engine rebuilt in my R3T and have about 150 miles on it (just haven't been able to get out since I brought it home two weeks ago). I am reading in other places about not taking it easy while breaking in a new engine but rather throttle it hard to make the rings seat. I am of such old school on this matter but can change my way of thinking, with a good investigation and evidence from others.I grew up being taught to take it easy at first so as not to scuff a piston or scor a bearing. It seems like I read somewhere that carpenter racing is in favor of the hard breakin but can't find it now.I am interested in hearing everyone's thoughts on this. Warp I know you are very familiar with these engines, your thoughts would be appreciated and everyone else's as well

Ridefree

 

[scot in exile]

Ride it like you stole it that is how I break in all my vehicles(and a few lady friends)

 

[HansO]

must admit like you I was always told to break them in slowly but in recent times they say not to baby it to much, so I take it steady dont go over 3,000 first 500km (300 mile) then gradually extend it revving it out steadily with no snappy throttle till a about a 1000km (600 mile) then ride it normally but avoid staying at a constant rev to avoid glazing also run a slightly lighter oil for the first 1000km and then change it, I am not saying that is the right way but how I would run in a fresh rebuild, I'm sure someone will shoot holes in it but that is it ..... there is always someone that knows more

 

[Claviger]

How I broke mine in last month (some would say it's still breaking in):
First 100 miles, easy, no full throttle, use engine braking as much as possible, vary speeds constantly.

101-400 miles, still want to vary speed constantly, however, now you want to use all throttle positions including full open and dont pull clutch and coast, use the engine braking. Gradually raise the RPM you run up to, until by 400 RPM you are hitting Redline or just shy of it.

401-500 miles, ride it, ride it hard, ride it like you fking mean it. Don't abuse it, but do use all of it. Getting on a freeway? WOT in 2nd gear till redline, 3rd too if you're feeling fruity
Getting off a freeway? WOT in 2nd gear till redline.

Get your service at 500, then ride however you want to.

There is a plethora of anecdotal evidence and some hard evidence that babying an engine early in its life is the worst way of breaking it in. The goal is to get maximum cylinder pressure/vacumm applied to the rings, it slightly flexes them and cleans off the edges of the cylinder scoring and the rings themselves. This creates a good mating surface and will last a life time.

Additionally, bearings, you will want to be gentle very early on (0-100 miles) to ensure the assembly lube gets time to be washed away and any imperfections are smoothed out, this absolutely doesn't take 1000 miles. The reason my method slowly ramps up the intensity is to allow this early friction surface cleaning throughout the engine. The 101-400 period is for the benefit of the rings/bores. The 401-500 period is really to identify weak or out of tolerance parts. This is the period where I want it to break if it's going to so it will be caught at the first service.

Bottom line is: All vehicle companies have good reason to say "baby it the first xxxx miles".
First: It is in their interest for you to ride easy as you get used to the bike, safety reasons.
Second: It ensures if you do have a critical part failure, you wont be going super fast.
Third: It disuades tards from going out and buying a bike and tracking it the same day then trying to claim warranty work on an un-proven motor before the first service.

My method has worked great for my last 3 vehicles, including the rocket, which I have the dyno sheet posted on this board done with only 681 miles on the odo. putting down 127/145 stock bike with a downloaded tune not a custom one.

Last performance engine I did was a Turbo 2.0L 4 cylinder making about 410 hp that I drove daily, raced often, and lasted 60,000 miles before it finally broke a ring land when I was drag racing in Arizona on a 105f day, whoops:-/

 

[IMFASTTOO]

SO you had the bike rebuilt or modified ?

 

[Ridefree]

It was rebuilt stock under warranty at 14,600 miles. Trans wasn't rebuilt but was torn down and measured out. In the engine the only things that weren't changed were the crankshaft, balance shaft, and cams. Even got a new cylinder head. The engine had a bad rattle mostly when cold in the middle of the engine that was still there after it warmed up but not as bad as when cold.

Ridefree

 

[Ridefree]

Also they put in the castrol synthetic and I have always been one to break in an engine on conventional oil. I'm thinking it would be a good idea to drain out what they put in and get some regular oil in it to continue the break in.
Claviger, your method would be about right with my engine now at 150 miles on it, it would be time to start getting on it some.

 

[Claviger]

Yep, really it's just about not being abusive while still working it. Hope all goes well, and I am both shocked and happy that they covered your motor under warranty!

 

[HansO]

definitely be changing that oil

 

[Ridefree]

Triumph couldn't get out of it because it was still under factory warranty. Bike is less than two years old