Jump to content

Engine Break-in Procedure


what

Recommended Posts

So it seems there are 2 camps on this topic - the "By the book, ease it in over the first 600 miles" group and then this group: http://www.mototuneusa.com/break_in_secrets.htm, which essentially says to wring the bike's neck for the first 20 miles, change the oil, then ride it as normal for the next 1180 miles (with another oil change at 600 miles) while varying RPM to properly seat rings seals/etc. 

 

Curious what views people have on this board about the subject. 

Edited by what
Link to comment
Share on other sites

33 minutes ago, JustinNck1 said:

I always just went by varying RPM. I don't take a bike to redline much anyways, so that isn't much of an issue for me.

I don't normally either. I'll ping the rev limiter briefly now and then when passing someone but it's not a common occurrence and not on purpose :p 

 

12 minutes ago, TimTheAzn said:

Never owned new...

I'd rather not own new myself, however this guy's claims of adding/losing up to 10% horsepower by properly/improperly breaking in an engine makes me wonder. His website looking like it was made in 1992 doesn't lend to me believing his claims, but that's just me and my shitty designer brain judging someone from their poor taste. 

Edited by what
Link to comment
Share on other sites

11 minutes ago, Isaac's Papa said:

Follow the manual. 

 

Now thats out of the way... Hot, cold, hot, cold. Avoid prolonged sustained RPM. (think interstate) Regular riding with short bursts of high RPM to creat heat and seat the rings and valves is how it should be done. No need to redline the engine, but it needs to spin up when it's warm now and then. 

Or follow the manual. That's also safe. Just avoid droning the engine. 

So if someone were to say, buy a new bike and go out for 600 miles of twisties while staying off the interstate, things should be in good order? Essentially. 

 

Link to comment
Share on other sites

That's the original purchaser's job. privilege?

With a hacksaw blade the harder/hotter you push the faster you dull it.

Wouldn't the worse break in procedure cause more emissions and be constrained by the EPA?

http://advrider.com/index.php?threads/motoman-rough-break-in.813543/ " I'll go with the guy who is going to warranty my bike for 2 years, not someone who isn't. "

 

 

 

Link to comment
Share on other sites

Fuckin ride it FFS.  I bought my bike, drove it 5 miles to home and loaded my shit in it and drove it 525 miles on freeway to get to the dragon. Then I drove the hell out of it for 3 days on the twisties.

50 thousand later it runs like a top and uses zero oil.

Now, granted my bike isn't one of those f'd up Italian or Brit things. Maybe those are different. :dunno:

  • Upvote 1
Link to comment
Share on other sites

3 minutes ago, Isaac's Papa said:

Yeah, but your bike falls under the "tractor" category. The same rules don't apply. We're discussing finely-tuned machines here. Not some overbloated Harley wannabe. 

Don't you have some valves to adjust? When you get done @what needs a hand with a battery change.

  • Upvote 2
Link to comment
Share on other sites

This is all so stressful, can't I just pay a premium for a new bike , then pay someone to break it in for me.

Re: hacksaw

Just responding to his claims of manf break in.causing crosshatching dulling and no longer wearing the rings to seal from lack of heat and pressure. 

" there is a lot less heat build up in the cylinders from ring friction 
due to the finer honing pattern used in modern engines "

Link to comment
Share on other sites

21 minutes ago, Tonik said:

Don't you have some valves to adjust? When you get done @what needs a hand with a battery change.

Hey I'm an expert at changing batteries, ok?

 

I should note, I don't have a new bike, I just stumbled on the motoman thing while perusing other motorcycle-related websites at work today and figured I'd see what people here thought. 

Edited by what
Link to comment
Share on other sites

A guy I work with got very intrigued with the motoman hard break in concept, then went out & bought a new Wee Strom. A week later, the bike was in the shop having the engine replaced (under warranty).  I stick pretty much to what the manuals say & haven't had any troubles.

  • Upvote 1
Link to comment
Share on other sites

3 hours ago, Isaac's Papa said:

Hot, cold, hot, cold. Avoid prolonged sustained RPM. (think interstate) Regular riding with short bursts of high RPM to create heat and seat the rings and valves is how it should be done. No need to redline the engine, but it needs to spin up when it's warm now and then. 

This is exactly the philosophy and practice that I have followed...makes the most sense to me.

Link to comment
Share on other sites

Brand new off the showroom floor.

Read your owner's manual and then get a FACTORY SERVICE MANUAL. (Fuck Chilton's)  Read it.  Bet there's a section commenting on breaking in at least the top end (pistons, rings, maybe seating valves.)

Re-built to new.

Whoever did your work (assuming he's competent and yes; they're out there) will have a chat on how to break it in, and probably what he does with fools who wring a new motor out, drag it back in with the pistons imbedded in the fairing or other body panels.  If you did your own work, you pretty much know already.  Unless you're rich and enjoy buying replacement parts over and over, having the bike trucked home; you'll damned well do it properly.

While we're on the subject, I am full well aware I am the dumb-assed knuckle dragging greasy Harley freak.  But I am also a mechanic of sorts, and cannot stand to see equipment abused.  Nothing uglier than spun bearings, busted rods and busted engine cases.  Dealer or independent shops who do your "warranty repairs" when you make scrap metal out of their product feel pretty much the same.  You who say ride it like you stole it...well, good luck.  I hope the OP figures out better than that.

Let the flaming begin... :D

Link to comment
Share on other sites

Most of the anecdotal advice on break-in is based on old wives tales from decades ago before cylinder bore machining and low-friction cylinder wall coating was as advanced as it is today, and before oil chemistry was as good at keeping things lubricated.  The old saw about running a motor hard after a rebuild--or from new, for that matter--comes from the old racer mentality that you had to "mate" the cylinder bore to the rings quickly, else once the motor had gone through several heat cycles the rings would never seat properly.  Of course, you gotta remember those old racer boys needed to quickly have their engine running smoothly on Friday night after spending all week rebuilding it...and of course, they were also rebuilding it a second and third time later that season!  Not a whole lot of time for that 500-1000 miles of gentle break-in.

May have been a small kernel of truth to it 50 years ago, but it's as false today as the other old wive's tale that you should never use synthetic oil to break in a new engine, because the oil is "so slippery" that the rings won't ever seat properly.  I suppose that must be the reason why Ferrari, BMW, Mercedes and GM's Corvettes are all filled with Mobil 1 synthetic from the factory, because....well, never mind.  What do they know?

The recommendation to run the engine at mid-RPM with less than sustained full throttle for extended periods while using varying throttle inputs during the first few hundred miles does several things:  first, full-throttle acceleration produces lots of upper cylinder pressure, actually pushing the rings AWAY from the cylinder walls allowing unburnt fuel to leak down into the crankcase and dilute the oil, as well as putting excessive loads on rotating parts like main and rod bearings and crankpins which are still wearing in; second, by varying throttle input, you create a partial vacuum in the upper cylinder when you close the throttle plate, which helps pull crankcase oil past the still-seating rings, helping to lubricate the rings, cylinder walls and combustion chamber early in the engine's life.

If you like your new bike and want to get the best performance from your new motor, follow the manufacturer's recommendation.

Edited by Bubba
  • Upvote 2
Link to comment
Share on other sites

Never owned a new anything. I have however rebuilt the top end of one of my bikes. 

Before the first real ride it spent a lot of time idling and revving, not high revving, but maybe 6k rpm. 

 

First few real rides I got up into the power band, not too deep into it and not for too long, but I put some good pressure on the rings. 

 

Did a lot of in town riding, lots of shifting, not much cruising. Did that for a few hundred miles. 

 

After that, I'd take it out and flog the monkey-dog shit out of it, pretty much every ride. Just abuse the fuck out of it, 10k redline? That was stock. Hold it open till it stops pulling hard. 

 

Damn motor runs like a Swiss clock now. Sure, I used overbore pistons coated in nicasil, and had the bores professionally honed before my build, but most modern engines have those coatings, right?

 

 

Link to comment
Share on other sites

First 600 under whatever rpm with varying engine speed. Changed oil next 400 miles a little bit more rpm but going a little higher then a few redlines for grins and now I ride it same way I drive my car. Normal shifting under a certain rpm unless I want to go fast then I'll stretch its legs twice a day or so when commuting on entrance ramps. Of course only when it's warm. 

Link to comment
Share on other sites

On 1/16/2017 at 8:15 PM, Wandering Soul said:

Didn't see whether he brought new or not.  When I'm unsure I ask.  :dunno:

I didn't buy anything, I just saw the motoman thing posted on another forum and was curious what people here thought. I followed the manual for my first bike (SV) to the letter. /shrug

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...