Jeff, thank you for sharing this! I get this question all the time and have responded in kind. Ride it and stop over thinking it.

Marty Smith once told me that the strongest engines he had ever had were engines that were installed between motos after a 1st moto seizure. Thanks for your time

I think this what my hearing is going to be like when I'm 80. Thank you for that Jeff. lol

I was on a large turbo performance engine project for an OEM a few years back, the run-in procedure was to ramp in speed and load until maximum speed (with reduced duration at each point), then boom it's ready to begin dyno testing.

I recently returned to dirt after 35 years & sent my cylinder off for plating. I literally stumbled upon this instruction. Thanks for the info! I've read over many threads & methods, most are apparently wrong.

I kinda learned this by happenstance and experience. This guy is absolutely 100% correct. You have to run them! Load em up with high load but not pegged wide open through every gear. Load is key!

I always did it the way you do.The only thing I did try to do was use a bottle of Kawasaki racing oil for the 1st time.I used it in KTM's .That oil was a full petroleum oil at the time.I only now have 2 of them bottles old style bottles left but I don't buy new bikes every year when they hit the 10k price range .I've had 25 KTM's so far & will get # 26 whenever I think it's time to up date.

My exacts thoughts on what I'm gonna go and do tomorrow for my 1st break in.. Get on it and ride the f****r Thank you for making people's live easier. Your rebuild video is class on the KTM 250. Helped me a lot. Perfect 👌

Dear Jeff, Thank you for sharing your knowledge and experience. I just found your channel, and learned about your store. Would you be so kind to confirm that the processes you explained in this video pertain to forged pistons also?

Like the old adage goes, if you want a motor to go hard you need to run it in hard. Paying heed to the difference in flogging a motor and just working it of course.

You said that factory teams just get on and ride, But do they rebuild the engine after every race or few races?

Jeff i have a 2001 ktm 200 exc and I'm 16 just did a top end to night and i don't have anyone to really go by so thank you for your information

i always tell my customers to ride at 50-75% full pace for a few laps then send it. i rebuild a couple dozen bikes a year, never had any come backs from that.

Do you richin up the oil mixter for break in

I follow manufacturer's guidelines as closely as possible for run-in. Everything needs a little run-in not just the engine.

So much knowledge and experience. Thanks for sharing.

Glad i found this. I could sense the BS everywhere else. Thanks Jeff I subscribed.

The first time I bought a new chainsaw I did heat cycles. Later on I took the muffler off to see what the piston looked like, and it ended up having scoring on the piston. I haven’t heat cycled anything since, just run it how it’s going to be run normally.

Seems pretty clear run it, ride it, enjoy it.

I've never broken in a new bike in my life but I'm a break in type of speed rider with enduro! LOL I DO warm it up in the winters! I've been lucky but I've only seen one new bike seize up after 10hrs a 2020 husky te300i. He did not break it in like suggested!!

Yes ...... I also agree for the most part with this break in procedure listed here. My 43 year piece to add is this, I feel there is nothing wrong with warming a motor up a little more, maybe for 3-4 minutes before you take off and ride ( easy ) for a several minutes as listed. With todays larger capacities radiators, super coolers, liquid ice type anti-freeze additives that many people add to there machines today make motors warm a little slower then a decade or two ago. His opinion here is a solid one and a great way to follow in breaking in motors. I just am a little more easy on the new parts !

Does it matter on the break in procedure you advise on whether the piston is cast or a forged piston ??? Or it doesn't matter ??? I prefer forged pistons .

Awesome advice. Once the rings have heat cycled do they not harden?? so the put putter idle around take it easy guys a doing themselves in as you said. Great vid!!

hell yea thats right. Gotta SEAT THEM RINGS. best way is to just go.

There's so many opinions. One guy suggested that you don't hone cylinders during rebuild.

Hey Jeff, Curious to know what your thoughts are on 2 stroke engine braking ? Coasting down a hill in the trail without having the clutch disengaged etc .. ?

You romp.on it right away ..then 15 minutes later you revved it?..didn't you rev it when you romped on it early?..or do u mean you rang it all the way out after only after 15 minutes of going thru the gears

Hey Jeff i fully agree with your video here its how I've run every bike in from new or rebuilt. out of curiosity and a little off topic do you know how much hp the new 2017 250sx is putting out? Cheers

Long story short, warm up for 2 mins. Then ride it moderate to hard or in my eyes, Wide open (almost)

Agreed! Ride it, vary rpms, and just don't lug it.

Great video sir, thank you!! I was wondering how the pros did it and was going to just do that way any how. Good to have some validation. SOOOO.. the next big question!! Install piston and rings dry or wet? If wet how wet? Heard one guy suggest to coat the bore fully and then wipe with paper towels until there's nothing coming off on it.... dunno? Thoughts? Thanks in advance!!

accurate information Jeff. thanks for posting.

How long should I ride it like this before I can rip on it?

Hey Jeff, besides being a waste of money, what's your opinion on running Amsoil Saber in a new 300 at say, 50 or 60:1? Would it foul up the plug or cause unnecessary carbon deposits?

You should do one on the myth of engine braking. The net's full of people claiming it will blow up your engine etc.

What’s the difference between “romping on it” and “reving it”? Thanks in advance for your reply. Gonna break in my 2022 te 300i this week.

Great video....true wisdom.

Thanks for another informative video.

i'll definitely try this with my kx250 it's due for it's 3rd piston soon the guy that had it before me had it from new and he didn't seem like the type to fart about with heat cycles or baby it and the bike rips really hard so this makes sense.

Hi @slaverace1 is it the same procedure for tpi bikes even it they had the top end rebuilt? Thanks in advance. I have a race on Saturday and I don't know if I should first do one deposit being gentle on the bike or not...

so you said you'd get a good ways away from the truck to let it warm up and then start working it but then you said you would then wait 15 mins and then start reving it. but didn't you advise to let it warm up two to three Minuit's riding then start reving it and doing some pulls and riding harder. or is it not that sensitive as long as you don't let it idle around so long it glazes.

Jeff is it true that the pre-mix should be rich on this break in procedure , it’s something a mechanic friend said is a must , the rest he told me is the exact opposite of what your saying, so I’m thinking so was that bit of info, so I’m just going to run the 50:1 ratio I would normally run to break in this new top end , Thanks Jeff, great video

About to install a new cylinder and piston on my yz125. Would you recommend this break in procedure for the new cylinder? Also do you recommend lubing the piston and cylinder before install or installing the piston dry for better seating? Thanks!!

thanks

Thank you for the very informative videos. Do you recommend using a non synthetic oil, or a different oil/fuel ratio for break in?

So why do many (if not most) manufacturers have a break in procedure in the manual that typically involves heat cycles, reduced rpm and load, or some variation of? KTM and Yamaha do, for example. I’m only asking because I don’t know.

How relavent is this to sleeved cylinders

who is the SOB that left a dislike...

Jeff, you MUST use a wireless mic when doing your videos. I know I'm missing some words & phrases with a low volume and a pretty bad echo without the wireless. I like your videos, though.

I believe was a Jeff KTM team mechanic or something? Anyways, if you talk to the factory recognized mechanics, like John Talley from Partszilla, or Jeff, they give the right advice about break-in. Ride it! With common sense of course. This is correct advice. Don’t waste your time with the over-specific garbage about heat cycles and rpm limiting that litters the internet.

Just curious, what about putt-putting around when you're doing figure eights and such. I'm also not much of a rever, I prefer low engine rpm stuff... Should I then hit an open trail every once in a while and blow the dust off the piston? I remember you had to do that with the cars in the 60's to keep them running fresh, rev the crap out them once in a while.

I don't have Ktm I have cr85 are the procuers still the same?

do u do replating for a nikasil jug??? and do u rebuild crankshafts?

hopefully a few people learned something here. thanks !

I just rebuilt my 1993 WR250Z top and bottom end, wiseco piston kit included. Is this method still doable for break in?

You said taking a new engine and going flat out in 6th would be a step too far So how long do you ride it before you would say go flat out in 6 gear ?

should i still run 60:1 on a fresh top end or more like 40:1 i have a 03 ktm 250 sx

I have a KTM 300xc 2008. The previous owner had the jets for mix of 40:1. My engine has been freshly rebuilt after it seized, is 40:1 a good mix? Some are telling me 32:1. Please help

So we know that KTM dynos every bike, but what about the Japanese brands? Are they dyno'd as well?

I look forward to your videos but have a really hard time hearing them. Is it just me and old age?

Do I need to heat cycle a new yz250 that wasn't dynoed at the factory? I know putting and idling are bad but how do heat cycles cause glazing?

Hay Jeff, thanks for sharing your expert advice. Question for you and sorry this video has been out awhile now!, would a similar Brake in be used for a KTM 1090/1290? and would you suggest several early oil changes ? Thanks again.

Is that for 4 strokes also ktm excf 500

Do you recommend the first tank on a new motor be at a richer fuel:oil ratio? My manual says to mix at 32:1 for the first four gallons. Should I follow this or mix at the normal ratio?

Yes. Just yes.

Your volume needs to be turned up.

👍

Get closer to or somthing. Cant understand a word.

That’s ok if you got money to burn doing that will need rebuild no way would I do that to run it in

At least get a cheap Headset with a built-in microphone, it will plug directly into your camera. The mic MUST BE within ~10 inches of your mouth to record reasonably intelligible sound, closer is ALWAYS better.

Jeff Slavens The reason manufacturers dyno every machine is because letting a defective bike go out the door could cost them more than the damage they might be doing by testing them.This does not mean that this is the best way to break in a new piston, just the best for mass production. I would follow piston manufacturers break in instructions. Do you think you know more than the people who make pistons. If the new piston and rings are broken in after the first few minutes, how will avoiding full throttle and operating in the higher gears lugging. The first hour of operation cause problems if its all ready broken in you are contradicting your self.

Jeff- you have good info but your vids are not always good quality...consider adding some production values to your vids...like a microphone and a steady camera- or at least consider boosting the audio. Keep on geekin'

what about four strokes?