Can A Total Noob Rebuild A KTM 350 EXC-F Top End

[@dr.x4050]

Thanks for the video! There are very few videos of top-end rebuilds on late model KTM 4-stroke engines. The steady camera and no music also make it easy to watch.

[@BrokenEnduro]

You’re very welcome! I’m glad you liked it. It was fun to make. I barely knew what I was doing so I figured why talk and I like the mechanical sounds. Hope you’re enjoying the rest of the channel. Thanks for watching and commenting!

[@dashrides2679]

Good job Devon. 4 strokes are definitely more complicated, but you've just proven that it totally doable. The scary part is making sure you've got the timing chain and the cams back in the correct position. Great timing, we're dropping a top end video today too.

[@BrokenEnduro]

Thanks! There were only a few times when I felt in over my head. Hahaha! Great minds!

[@camerondale7897]

Very doable! I always suggest cleaning very thoroughly and then taking the motor out even for a top end. It’s easier to work on at chest level (especially if you have a motor stand). Label with wire tape organizer or label maker, and get a notebook to draw where everything goes, you can take pictures but remember that electronics can break. I also always suggest if it’s your bike you’re working on-for wires/ cable and tube routing to print off the schematic and laminate and keep it in your tool box and I can’t preach enough that the service manual should be more of a bible than a suggestion. Organization is one of your most valuable skills, it becomes a headache always looking for tools or bolts or trying to remember where things go (which is another thing where the wire tape or label maker comes in handy, and bolt organizers with a label on them make life so much simpler). Makes the whole process is so much less overwhelming, makes it more peaceful than screaming and cussing and wanting it to be over.

[@NikMeyerz]

Well done sir on both the edit and the rebuild! She’s a freshy again!!

[@BrokenEnduro]

Thanks man! It was a fun project! Glad I pulled it off. I'm glad you liked the vid, it was cool to try something different.

[@bryan-norden]

Great video. Not sure if I want to do that on my bike when I get up to 200 hours but this has inspired me to think about doing it. Awesome work. Anytime I work on my truck or now my bike, I always am like will it start when I am done. Such a good feeling when it starts after putting it back together. This has to feel awesome.

[@BrokenEnduro]

Thanks Bryan! From what I saw, it really wasn't necessary, but this has always been something I wanted to give a go. It was the sweetest feeling to hear her fire up!

[@idlehandsenduro6659]

No more smoke! Well done, and cool video.

[@BrokenEnduro]

Only one orange smoker in the garage now! Glad you liked it. Kind of a mechanical ASMR. Hahaha!

[@Momfasa]

Nice job! I will do this too in the upcoming winter.

[@BrokenEnduro]

Thanks! Making the video was actually helpful when it came time to put it all back together. Thanks for watching!

[@DirtBikingwithDonnie]

Nicely done! Enjoyed the video.

[@BrokenEnduro]

Thank you! I'm glad you liked it. It was a fun project and very different from my normal vids. Thanks for watching and commenting, I really appreciate the positive feedback!

[@frebuton2016]

Awesome Job! Something learnt and money saved. Win Win!

[@BrokenEnduro]

Thanks Andre! I'm so happy that I talked myself into trying this. Very rewarding project.

[@John_Doe_6996]

Paid 5k for a used 2016 FC250. It lost compression and stopped starting after I rode for roughly 2 hours. Top end kit will arrive in 2 days. Can’t wait to get it all rebuilt and actually enjoy the bike! Wish me luck.

[@BrokenEnduro]

Good luck! Hope the video helped.

[@JO-id6ms]

Great video, thanks for taking the time to make this

[@BrokenEnduro]

Thank you! You're very welcome. I'm glad you enjoyed it!

[@jasonlawrence8302]

always feels good to do it yourself!! good job!

[@BrokenEnduro]

Thank you! This one felt like a huge win!

[@banshees111]

Thanks for the video. Got me thinking I could take this job on. 130hrs on my EXC and getting some smoke on start up and little oil being used. Probably valve stem seals. I wish I was one of the 500hr guys, but anyway....so be it...

[@BrokenEnduro]

You're welcome. There were only a couple times where I thought I'd gotten in over my head, but if you take your time and stay organized, you can do it. Sorry to hear you're already smoking. Those valve stem seals seem to be the weak link. Thanks for watching.

[@ctone12]

Lucky you, my 2015 FC 350 I had to take the entire engine out to swap the top end, also I concur that valve replacement is tough as hell 🤣

[@BrokenEnduro]

Oh what a bummer. I was so happy to have to pull the motor. Valves suck. Haha! Thanks for watching.

[@desert-frog]

I’m stoked that you were able to get that done. I’m thinking I can do like myself too. Would have been nice if you talked about what you were doing as you were doing it…good job tho

[@BrokenEnduro]

Thank you! It was very rewarding to complete. My thought on doing is silently was that there are many video out there, made by people far smarter than me, if you wanted detailed explanations. I thought it would be fun to just quietly show the process with nice audio and video. Thanks for watching!

[@americandirtrider7662]

So I know the engine CAN go pretty long without needing a rebuild. But doesn't the KTM manual recommend a rebuild every 2 or 3 days?

[@BrokenEnduro]

That sounds about right. I think KTM says to rebuild four times per lunar cycle! Ha!

[@davidb9323]

Well if you failed it has the proper stickers on the bike “broken enduro”. My local KTM dealer won’t service my EXC-F with a top end giving me some BS about how because it’s a Husaberg it is different. Another dealer (Husky) said they can’t get parts through the distributor they use so they won’t do it due to not using customer supplied parts or inability to warranty. Neither of them sold Husaberg in the past so I guess I’m SOL. May have to do this myself as well!

[@BrokenEnduro]

That is so annoying! I hope you can source the parts and figure it out! Good luck!

[@alexjohnson3696]

Great video, thanks for sharing

[@BrokenEnduro]

You're welcome! Glad you enjoyed it!

[@RichLaffertyRacing]

what did you take out front motor mount bolt and what is marks for top dead center.....just curious cuz about to do my first stroker by myself..thank you

[@BrokenEnduro]

There’s a small bolt you can remove, remove a thick washer, and replace the bolt to lock the motor in top dead center. There are two marks to reference top dead center. If you have the same motor, the marks need to be in the center, pointing towards each other. Hope that helps.

[@alexjohnson3696]

Thanks so much for this. What were symptoms that prompted you to do the rebuild? Or was it just the number of hours? Thanks again

[@BrokenEnduro]

You’re welcome! I did the rebuild because the bike was doing a cold hard start and smoking until it warmed up. Hope it helps. Thanks for watching!

[@raphihuberclimbing8730]

Nice job. But y'all need to use screwdrivers instead of power tools. Screwing up the threads... Also gives you somewhat of a more intense connection to the thing.

[@BrokenEnduro]

Thank you. I was trying to avoid power tools, but this project took so long because I was filming everything. Maybe next time. Thanks for watching!

[@troybryant2117]

Wow! Great video👌 Well Done Indeed

[@BrokenEnduro]

Thanks Troy! I was pretty pleased with myself. I’m fairly mechanically inclined, but I’ve never gone this deep into a motor. Great experience. Thanks for watching and commenting!

[@repomannv]

Thanks for the vid, looks like my 2020 EXC-F top end just shit the bed at 16 hours (white smoke pouring out the exhaust, very unhealthy clickity-clackity sound from top end), so I'm sitting here hating my life, drowning my sorrows with a big gulp Mtn Dew, before I go rebuild it.

[@BrokenEnduro]

16 hours?!?!!?! Was it sitting for a long time? I'm sorry dude. I hope the video helps you along the way. Thanks for commenting and watching.

[@repomannv]

@@BrokenEnduro Well, a 2020 with 16 hours isn't getting ridden a lot but it hasn't sat rotting in the garage either, hopefully its something simple in the top end like broken valve spring. Should know in a day or two when I get after it, I just want to ride, not wrench 🙂

[@leewebb1433]

Thanks for posting this. I did see a 2017 250f video and the head wouldn't clear the frame so not sure what's different?

[@BrokenEnduro]

That's interesting. It takes a bit of convincing, but it can me done. Glad you found it helpful. Thanks for watching!

[@Bakedpotato1]

Not a noob anymore that's for sure, you did well, no correct way to do it, just get it done and hope that you did it right, but having a lot of pictures really is the key to doing it correctly. the contamination i guess comes from air filter, try and inspect the carburator and fuel filters, it does have quite a bit of it.

[@BrokenEnduro]

Thank you so much for saying so! I was a bit nervous putting this out there…the internet can be cruel. Thanks for watching! Thank you for the tip, I’ll look into it.

[@Bakedpotato1]

@@BrokenEnduro your welcome and i get why you would be nervous about posting here, but i really think alot of people are gonna appreciate your video, it shows that engines are not all that complex but rather easy to maintain, could push alot of people to get into riding these bikes. i'm thankful you posted it mate !

[@BrokenEnduro]

@@Bakedpotato1 You're welcome! I hope so. It was actually a lot of fun!

[@Bakedpotato1]

@@BrokenEnduro I bet it was :)

[@advsquared]

So did you really make the video so that you would know how to put it back together LOL!! Something tells me these bikes can go way past the "recommended" time before a rebuild.

[@bryan-norden]

That’s smart! I totally agree since he said he wasn’t planning on making this video lol

[@BrokenEnduro]

The thought of knowing I had a recording of how it came part did cross my mind, but I actually made the vid for John. He asked me if I was gonna make a video just before I got started. I'm sure it could have gone much longer, but this is something I've really wanted to give a try and I wanted to put an end to the cold start smoking.

[@BrokenEnduro]

@@bryan-norden Little back up plan. Ha!

[@advsquared]

@@bryan-norden I find taking pictures of how wiring and hoses are routed really helps when putting things back together again.

[@advsquared]

@@BrokenEnduro Did you figure out what was causing the smoking on cold start up?

[@psrod7]

200 + hrs how many miles? Great video by the way I learned a lot thanks.

[@BrokenEnduro]

I think I've got about 5,500 miles on the bike. Thank you so much for the kind words! I was a little worried about trying a video like this. Seems people enjoyed it. Thanks for watching and commenting!

[@kaleb97045]

Nice work! I have a 17’ 350 excf with 550+ hours on it. Been debating doing a top end/full rebuild but it runs just fine, starts without issue, doesn’t burn any oil or coolant, never even needed to adjust the valves. Was yours giving you trouble or did you do the top end for preventative measures?

[@BrokenEnduro]

Thanks Kaleb! Dude! That's a lot of hours of awesomeness! So my bike started to smoke quite a bit when it was cold. Doing the top end was a bit of preventative work and curiosity. I didn't want the burning oil problem to become a bigger issue, and I've always wanted to try to rebuild a top end. I really enjoy working on my bike and always learn a lot. Like yours, I've never had to adjust the valves and I check them all the time. They seem to be great little motors. Thanks for watching and comment, I'm glad you like the vid, it was a fun one to make.

[@glenndavis2762]

Following this new generation of motors and quite a few guys are getting 600, 700 hrs before tearing in on these motors and changing the top ends - Bottom ends seems to be good for around 1500 hrs. Same with the 500's and 501's. - valve checks every 200 miles is common now.

[@glenndavis2762]

@@BrokenEnduro where did you source your piston kit and valves? What brand did you buy?

[@BrokenEnduro]

@@glenndavis2762 I completely agree! I'm constantly checking my valves because I'm curious to know if you need to stick with KTM's suggestions. They have NEVER needed to be adjusted. My top end job was more of a learning experience for my self than anything else.

[@BrokenEnduro]

@@glenndavis2762 I got everything from Rocky Mountain ATV MC. I used ProX valves and a Wossner piston. Thanks for watching and commenting!

[@marcospacheco2947]

Muito bacana suas explicações legal ajuda muito Parabéns

[@BrokenEnduro]

I’m glad you found it helpful! Thanks for watching!

[@TwistedTriggerEnduro]

Great video! I absolutely love your custom graphics. Do you mind if I ask where you got those? Thanks for posting. 💪😃

[@BrokenEnduro]

Thank you! Glad you enjoyed it. I ordered the graphics for Motocal.com The website has a bit of a learning curve, but once you figure it out, you can go some pretty cool things! Thanks for watching.

[@TwistedTriggerEnduro]

@@BrokenEnduro Sorry I didn't reply to this. Thank you SO much for letting me know the website. I'll have to get something made up in a few years when it's in the budget. You're awesome!!

[@BrokenEnduro]

@@TwistedTriggerEnduro You're very welcome! I know the run discount codes all the time and post them on Instagram, if you wanted to check it out. They are usually 25% off.

[@adrenalinaddict8212]

Awesome video! I have a '18 EXCF 250 with 174hrs on it and I don't know much about 4-strokes motors. The dealer tells me I should put a new piston in it, but you know a dealer, they want to sell you as much as possible. My bike starts like a champ, don't burn any oil, and for me it runs just the same as when I bought it. What bothers me is to not be able to see what the piston looks like ahah! I guess I'm still good for a couple of hours. I'll refer to your video if I ever decide to do it myself when time comes :)

[@BrokenEnduro]

Thank you! I'm glad you liked the video! If I were you, I would leave it alone until it starts to smoke or is hard to start. These bikes can take way more abuse than what the suggested maintenance is. Someone in our club has a 250 EXC-F with like 400 hours on the stock piston. Thanks for commenting and watching!

[@adrenalinaddict8212]

@@BrokenEnduro Well, it's reassuring! I'll pay attention but won't touch it too soon, thanks! 🤟

[@BrokenEnduro]

@@adrenalinaddict8212 👍

[@inthepumpkinpatch5383]

Holy crap good job I don't know that I've ever been game for this Job . I bet it helped having the 300 Just in case it turned to a pile of parts lol

[@BrokenEnduro]

Thanks man! I've always wanted to try doing this. It was pretty intimidating, but I enjoyed it, except for the stupid little things that keep the valves in place. Those sucked putting back in. The 300 would be more than happy to be an only child! Just gotta get her a plate!

[@danielbarros8136]

Great job buddy! If you don’t mind, What brand of valves did you use and where did you get them? Did you adjust your valve shims after that? Thank you

[@BrokenEnduro]

Thank you! I honestly don’t remember. At the time, just getting parts was my big concern. I was ordering from everywhere. I did have some changes to make to the valve shims and they were still in spec at the next valve check. Thanks for watching!

[@danielbarros8136]

@@BrokenEnduro I appreciate your quick response, I’m about to change only my valves and I’m concerned about my new valves sealing right without new valve seats re work, hope this works for me too, greeting from Mexico pal.

[@BrokenEnduro]

@@danielbarros8136 Your'e welcome!

[@hyposez1129]

Did you use a torque wrench to tighten the top end bolts or anything like that? Because like at 10:58 you didn't use a torque wrench to tighten the bolts. And sorry for bad english!

[@BrokenEnduro]

Yes I did. I didn’t make the edit, because torquing every single bolt was not that interesting. Thanks for watching!

[@JohnSmith-ep2hh]

Just had mine rebuilt by a garage after a valve collapsed ruining the head, piston, and inlet cam. Mines on 210 hours and cost nearly £1500 for the work so doing what you did, when you did, will have saved you HUGE money. One quick question…. What was your procedure for running in the new piston????

[@BrokenEnduro]

Man, I'm sorry to hear about your bike, that's a real bummer. As far as break in, I brought the bike to temp, let it cool. Gently rode it for about an hour, let it cool. Took it on a really ride, but tried to keep the RPMs low. Changed the oil. Rode it like normal. I'm sure there are a million opinions on how to do it, it is the internet after all, but that's what I did. Hope that helps. Thanks for watching!

[@dougwisdom1239]

My 350 has over 360 hours on it, it's time to run a compression leakdown test. It's been an awesome bike, I've owned several bikes since 1973 !!

[@maffthetaff8625]

great vid mate,, can i ask, where did u get the ignition barrel from oe was it on when you got the bike, that would be a great addition to my 19 husky.. 😉👍

[@BrokenEnduro]

Thank you, glad you liked it. That’s the OEM one, it’s been relocated with the Highway Dirt Bikes dash. It’s a whole hand guard system, and I love it! Thanks for watching.

[@MrGingerer]

Hey man, i know the video has been out for a while… where did you buy all the parts for the rebuild? Been looking online, dont know if i should go OEM or aftermarket. Thank you!

[@BrokenEnduro]

Parts were really difficult to get when I did this. I got most of the parts from Rocky Mtn. I can’t remember where I got the piston from, but I remember that was the toughest to source. Hope that helps. Thanks for watching!

[@davidb9323]

@@BrokenEndurolooking for a piston myself

[@karf450]

Did you have to resurface the cylinder head? also did you use a new head gasket?

[@BrokenEnduro]

No. Just cleaned up the carbon build up with a Scotchbrite pad. There was no pitting or scars and it was during lockdown, so getting anything done would have been tough. Yes on the new gasket. Thanks for watching!

[@owenpetrie1247]

Great vid! I have a 18 350 XCF that is smoking like a two stroke and sitting. Xcf and excf are the same top end job?

[@BrokenEnduro]

Thank you! Other than some smog crap that’s on mine, I believe they are the same motor. Thanks for watching!

[@christoforospilitsis541]

You just pop the old valves out and put the new valves in?

[@BrokenEnduro]

I was able to, there was no damage to the head. The carbon build up cleaned up fairly easily. Thanks for watching!

[@lucab69]

Sick vid! Did you ever change out the plastic oil pump gear? Been reading about those recently.

[@BrokenEnduro]

Thanks! Glad you liked it. I haven't, I'm still running the original one and haven't had any issues. Probably because of the sweet oil I run! Thanks for watching and commenting!

[@MrHackproductions]

witch brand was the new piston OEM? nice vid

[@BrokenEnduro]

I used a Wossner piston because it was the only piston I could find in stock at the time. Thanks. Glad you liked it.

[@andrewsoldan6050]

just doing the same, did you put same size piston or second?

[@BrokenEnduro]

I used the stock size piston. All of the measurements and gaps worked with the stock stock sizes. Thanks for watching!

[@watts300]

You said the valves was a total nightmare. Why was that?

[@BrokenEnduro]

Maybe not a nightmare, but the tiny valve keepers were a pain. A third hand would have been useful. 🤣 Thanks for watching!

[@justinwhite7863]

Hey awesome video,, I'm picking up up 2014 tomorrow! How long did the rebuild take for you to do start to finish?

[@BrokenEnduro]

Thank you! It was a fun one to put together. Congratulations! You know it's hard to say. I think it probably took half a day. I'm sure I could do it much faster now that I've done it and if I wasn't filming it. Thanks for watching and commenting!

[@MuddyFenders]

who makes that orange case guard?

[@BrokenEnduro]

Acerbis makes them, but I think they might be discontinued. Hope you can find them!

[@DirtRidingLarry]

So if the 350 blows up I know who to blame 👀

[@BrokenEnduro]

It hadn’t after 80-90 hours. 😂🤷🏻‍♂️

[@DirtRidingLarry]

@@BrokenEnduro but now I touched it...

[@ivanpirozhkov4940]

Nice job)

[@BrokenEnduro]

Thank you! Thanks for watching too!

[@coarsegoldkid]

How did you get the circlip off the piston. I'm about to give up.

[@BrokenEnduro]

I was able to get it out with a little pick tool. Sorry it’s giving you a hard time, hope you can figure it out.

[@coarsegoldkid]

@@BrokenEnduro Thanks I got it. Now to wait for parts.

[@moonshineexc]

My header pipe slides straight off on a 2019 excf 350

[@BrokenEnduro]

Just a bit seized by heat.

[@thambu19]

Great vid. thx

[@BrokenEnduro]

You’re welcome! Glad you liked it. Thanks for watching!

[@robsonenduro3316]

nice, what year is the bike?

[@BrokenEnduro]

Thanks. 2018.

[@bigals.ktms.9937]

So after 200 hours did it actually need a rebuild.?????

[@BrokenEnduro]

The cold start smoking went away, so it was worth it. I'm not sure if it really needed it, but I'm glad I did it. Thanks for watching!

[@andybishop82]

How many hours/miles was in that engine?

[@BrokenEnduro]

At the time there was a bit more than 200 hours. I can't remember the mileage. Thanks for watching.

[@HugieMaceachern]

Dont have to hone them?

[@BrokenEnduro]

There was no vertical scoring, crosshatching still looked really good, and the ring gap was in spec. If you’re supposed to, I didn’t and everything was just fine.

[@d.o.m.adventures6942]

When you change out your rear tire, do you have to remove the clutch lever LOL...Great job man and what a feeling of accomplishment! Instead of building more prisons, we should make people that break the law remove and replace valve spring keepers for hours on end and I guarantee they'll behave...

[@BrokenEnduro]

Good catch! The clutch lever was removed before I pulled the rear tire! Luckily ever other fuse was already pulled, so the lever removal was a breeze! 😂 Of the entire process, the valve spring keepers were the only part that sucked. You seriously need three small lady hands to pull it off smoothly.

[@mke7876]

I take it you use motorex 1050

[@BrokenEnduro]

I did for a long while and since switched to Reverend Motors. Did you have a similar carbon build up issue?

[@mke7876]

I had a little carbon. The guy that rebuilt mine suggested to stay with the oil I was using Or amsoil

[@Gabriel19-87]

hours??

[@BrokenEnduro]

A bit over 200. I’ve got like 260 now.

[@waldirscherrjunior8657]

ou seja um motor que rodava pelo menos 400 horas , nao consigo entender como desmontar um motor sem apresentar nenhuma falha , isso e coisa do passado , hoje os motores estão muito melhores do que os de antes . isso para mim e jogar dinheiro fora , desmontar uma ktm de uso normal antes das 400 horas .

[@waldirscherrjunior8657]

mas de qualquer forma, um ótimo vídeo , bom que eu sei que como meu motor vai estar . muito obrigado pelos vídeos .

[@BrokenEnduro]

@@waldirscherrjunior8657 My bike had been smoking pretty badly when it was cold, so I had a feeling the rings were bad. Doing a top end on a four stroke is something that I've always wanted to try. I learned a lot and I'm happy I did it. I'm glad you like the video! Thank you for watching and commenting!

[@waldirscherrjunior8657]

@@BrokenEnduro quando esta fumando pela manha ou quando liga , na maioria das vezes sao os retentores de valvulas , aqui no brasil, as motos de enduro rodam em torno de 300 a 400 horas ate fazerem preventivas , muito dificil quebras , agora motocross e sempre um pouco antes mesmo . muito obrigado , fique com Deus

[@BrokenEnduro]

@@waldirscherrjunior8657 Thanks for the info!

[@ssse3123]

Noobs dont have valve spring compressors, magnet sticks, pipe spring pullers etc. This is clickbait :)

[@BrokenEnduro]

Hahaha! Okay, so not a noob to figuring things out, but I've absolutely never gone that deep into a motor. I actually ordered the spring compressor when I ordered all the parts for the job! Thanks for watching!

[@glenndavis2762]

@@BrokenEnduro Got a link to the spring compressor you used? - Great job by the way!

[@lifephilosophy6861]

I think maybe you need t

[@BrokenEnduro]

T?