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Yeah I would say 4,000 rpm is a little rough.
But I'm doing my best here, I have around 350 miles on my bike and I have been keeping it under 6K rpm and no full throttle runs. TBH, I have been to like 6,200 RPM a couple of times when traffic requires but nothing more than a few seconds. I am a firm believe in a good break-in period.

I am more curious if you guys ride around at 40+ mph all day? After 40MPH it's all 6K+ RPM. Does the motor mind this? Will this shorten engine life?
 

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Everyone is going to have their opinion. I think the best breakin is varying the RPM while trying to avoid keeping it steady for too long, In addition breakin periods are more to make you baby the bike to avoid any real warranty work. For a bike this small its hard to keep it under 6 or 4k. I've been riding mine full throttle from day one but its been converted to a race bike so to each their own.
 

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I literally just got my Z Monday and rode it home from the dealer I bought it at just under 180 miles from my house... the first 50-60 miles I constantly varied my RPM, at that point stopped for some lunch so the bike sat for 35-40 minutes, after that it was straight through the remaining miles home. The dealer told me the “first service” is 600 miles but do to my unorthodox break-in I think I’m gonna change mine now then again at 600 just for good measure. Did you guys do the typical 600 mile first service or go with something different?
 

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Running WOTATT will most likely shorten the lifespan of the motor but it's a toy... use it how you want to use it and deal with the consequences as they come. The worst I've heard is a bit of oil blow by at 5800 miles, otherwise most of us ride hard and have zero problems.

The dealer told me the “first service” is 600 miles but do to my unorthodox break-in I think I’m gonna change mine now then again at 600 just for good measure. Did you guys do the typical 600 mile first service or go with something different?
I did 200, 600, 1000 for my two Zs. (The previous owner of my 2017 changed the oil for me before I took it home.... at 18 miles!)
 

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I did my first oil change at 300 because I didn't know how long my actual bike had been sitting at the dealership on the showroom floor. It was overkill because the oil was still golden brown, almost looking brand new. I'll do the next change at 600 miles again but I'll just follow what the manual says after that.
I used non-synthetic oil as I read here and there that these little bikes with their wet clutches like it better than full synthetic.
 

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i think the first oil change was around 80 miles with a filter change, then every race weekend i drop the oil for fresh oil without the need to change the filter. I think theres another filter that needs to be cleaned every once in a while or swapped out that requires a bit more work. I haven't done that yet but I don't even have 400 miles on mine yet.
 

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Ah yes, the old break-in discussion. I thrashed mine at the racetrack for 50 laps (about 50 miles) and then dropped the oil. Did it again one more time at 100 miles if I recall. It's the best way. You know how I know? Data.

I've done compression checks on most of my new engines to see how they break in. With the baby Z my compression went UP a bit after the hard 50 miles, just like I expected it to. If you want the rings to seat well, you don't want to baby your engine. If you do there's a good chance you are stuck with lower compression, lower performance and higher oil usage. I learned that with compression tests I've done myself on new engines many times in the last decade.

I think if more people saw this for themselves there would be fewer people insisting on breaking in engines according to the manual. The real question is, if weak break-in is so bad for your engine, why is it in the manual? The answer is that lawyers keep it in there so new riders go slower and safer.

Quick summary - go hard and change the oil early. You'll have the best performing engine. After the first couple oil changes resume normal change frequency if you are a street rider. I change mine every other track day, so probably every 100-130 miles.

Compression testing kits are pretty cheap now BTW...
 

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Use the factory 10W-40 mineral based oil or a aftermarket specialty Break-in oil for the first 100-150 miles (non-synthetic).
The worst thing you can do is baby the engine or allow it to idle for extended periods.
Use 1/4 to 3/4 medium/aggressive throttle going through all the gears as much as possible and avoid any prolonged steady throttle rides.
Most high performance engine builders agree its safer to not ride at max Rev-Limiter or WOT.... But not a absolute.
Then after the 100-150 miles switch to a full-synthetic or semi-synthetic and your ready to ride or race to Rev-Limiter and WOT
Exceedingly long break in periods are age old standards set by manufactures when motor designs did need a longer break-in period.
And only leaves them in a better position to avoid liability and warranty costs for the entire bike not just the motor if everyone is babying there bike.
 

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Running WOTATT will most likely shorten the lifespan of the motor but it's a toy... use it how you want to use it and deal with the consequences as they come. The worst I've heard is a bit of oil blow by at 5800 miles, otherwise most of us ride hard and have zero problems.



I did 200, 600, 1000 for my two Zs. (The previous owner of my 2017 changed the oil for me before I took it home.... at 18 miles!)
Nice, that’s looking like how I’m gonna do mine. Changed it last night at 178 miles, will do again around 500-600, then at 1000 I’ll prob switch to Synthetic.
 

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FWIW I made the shift to semi-synth at 600 and had no problems.

If you really want to go overkill you should take the clutch cover off and clean out or replace the macro oil screen. Not a big deal but both of my bike's filters were ~1/3 clogged with inspection paint and other various gunk. Worth the $6 gasket all day IMO.

(And as long as you're in there install a $35 HD clutch kit. XD)
 

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I mean, it's possible... I spent a few hours last night just criss crossing back roads and side roads around a small town and put the better part of 100 miles on it...

Agree, it's probably impractical for a lot of people though.
 

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I was spared the dealer spiel. I had little choice but to run 7000 rpm on portions of my 25 mile ride home. Realistically I find that on city streets you can get around just fine shifting at 6K as you're well into the torque band. On subsequent rides around the Hollywood Hills I found I can keep it under 7500 but that's the best I can do. I'm not going to sweat it but I'm not planning on trying 9800 rpm anytime soon either.
 

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Ah man my friend was just talking to me about this yesterday 😅. I didn't even know about the break in period thing haha. I've been pushen my bike hard ever since I bought it from the dealer with 0miles. What should I expect now??
 
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