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Discussion Starter #1
So I found a shop that sells the Z125 Pro around me for a good price. I hear a lot about how there's proper ways to break them in and how you shouldn't redline it until it's broken in. The road that the dealership is on is a 55mph road and it's maybe 5-7 miles long. Is it okay to ride that speed on the first drive? Maybe I'm overthinking it lol
 

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A lot of people here (and other bike sites) swear by breaking a motor in "hard and fast."

I don't - all those machined surfaces have to mate to one another. I would run it gently for the first hour and then below 5000 rpm for the first couple hundred miles.

THE most critical time is the first half-hour or so. Beyond that, the importance tapers off a bit. Everyone pretty much agrees that by 600 miles, you're probably okay for highway speeds.

You WILL not hit 55 on a new, tight, un-broken-in engine. Best you will do, wide open, which is abusive on a green motor...will probably be about 48.

I would try to get a friend to haul it to your place, or else stick to the shoulder with your turn-signal on, showing a slow-moving hazard. Or, ask the shop if they can deliver - five miles isn't that far.

Or as a last resort, borrow or rent a pickup truck. This machine is LIGHT; two persons can easily load it with ramps, even.
 

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A lot of people here (and other bike sites) swear by breaking a motor in "hard and fast."

I don't - all those machined surfaces have to mate to one another. I would run it gently for the first hour and then below 5000 rpm for the first couple hundred miles.
I broke mine in by running it for 2 hours HARD at the kart track. Then I wrapped up the day and dropped the oil.

I've done before and after compression tests on several new bikes. Break in in hard and your compression goes up nicely. Break it in as per the manual's instructions and compression won't go up as much.

I've done teardowns on engines broken in as per the manual instructions and they never look at clean as someone who got on it hard and early.

In general, people who say "obey break in limitations in the manual" don't have the practical experience to know how bad that can actually be.

Did you guys know that every single engine is run up to redline several times at the factory during their quality control tests?

The break-in limitations in the manual are written by lawyers who have ulterior motives, and they don't have what's best for your engine in mind.
 

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The old "Break-In Method" argument is one I'm not going to get into. Bottom line is...your dollar, your choice.

Every major motor manufacturer, from every nation on every continent, recommends gentle break ins. I don't think they have a worldwide conspiracy.

Your money, your choice. The reality is, most of these machines won't see more than 20,000 miles over their lives, so it may not matter much...but do you want to have the choice of using it more, and longer, or see it burning oil or sidelined with bearing failure, at that point?

My take: Machinery is not muscle. You want to grow muscle, you use muscle. No pain, no gain.

Machinery is material. Material wears. New material has to mate to rolling/sliding surfaces.

Just my take, FWIW. Were I in that situation, I'd haul it home in a truck.
 

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"Oh, do you think you know more than the engineers at Kawasaki?" No, but think again if you think Kawasaki's best engineers are the grunts writing the manuals. There's a pretty good chance that the break in advice in manuals is they way it is because that's what they have been writing since the 80's. But there's other speculation that lawyers don't want new riders on new bikes riding hard and fast because it's a liability. Never underestimate how much lawyers affect what you see and read. Why do you think there are so many stupid warnings in the manual, especially the end user owners manual. Think about it - what would happen if the manual said "Be sure to make many hard trips to redline to properly break in your engine." Newbies would be crashing everywhere.

Gentle breakin creates machines that burn more oil. Pretty much for the same reason that engines with gentle breakin have lower compression. This is especially true with thumpers. Some worse than others, like the KLR650 dual purpose. Pop the head off and you know immediately if that bike had a gentle break-in. Not to mention that some of the KLR650's broke in gently tend to burn a quart of oil every 1000 miles.

Yeah, it's the old break-in argument. It's been beaten to death over the years. My advice, listen to people who actually work on engines, do teardowns and internal inspections, and run compression tests on engines of various break-in methods. 95% of the internet does not have that experience and base their opinions on the fear of not doing what they're told.

Anyway, I'm not one to ride a debate into the ground, so I'll leave it at that. OP: go ahead and ride it home I say.
 

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Discussion Starter #6
Who knew this could be such a divided topic lol. I think what I'm gonna do is drive it for a while on the side streets and then drive it home after I get a feel. That way I am lightly driving it for the first but and then being a little harsher later on. I'll try not to redline it much. Breaking in engines is such a tricky topic it seems
 

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Who knew this could be such a divided topic lol. I think what I'm gonna do is drive it for a while on the side streets and then drive it home after I get a feel. That way I am lightly driving it for the first but and then being a little harsher later on. I'll try not to redline it much. Breaking in engines is such a tricky topic it seems

Good choice. Breaking it in easy is not going to hurt it; breaking it in by running it wide-open with fifteen minutes on the engine...you can see the difference in opinion on it.

The thing to measure is, risk/reward. High risk, basically no reward...suggests you need not take the risk.

The thing everyone agrees on with break-ins, are...vary your speed and RPMs; and allow a lot of warmup-operation-cooldown cycles. Doing a steady-speed moderate-RPM marathon to get your miles in, is probably not going to break it in properly.
 

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The thing everyone agrees on with break-ins, are...vary your speed and RPMs
Even I agree on that. See, we can agree on at least something. ;)

Also get some good engine braking deceleration in. It helps seat the rings at least as much as getting on it hard.

For those that do the hard break-in, I better mention that it's important to drop the oil much sooner. Like 50-100 miles.
 

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For those that do the hard break-in, I better mention that it's important to drop the oil much sooner. Like 50-100 miles.
Do that no matter how you break it in.

I changed the oil at about 200 miles and I was SHOCKED at how dirty it was. It was almost as if they'd filled it with used crankcase drainings...does Kawasaki ship the bikes dry, or does it fill the crankcases on the assembly line? NASTY crap.

Oil and filter. Do it at the first hundred miles. My OWN opinion is to use mineral oil with the first change, because you DO want some normal friction to wear in parts, and you'll be changing the oil at 600 miles again.

See? We can agree on lots of things.
 
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