2023 KTM 300XC Top End | TBI 300 Top End | 300 TBI Top End | Highland Cycles

[@Shelby8371]

Morgan’s a Real mechanic and all around good guy..people learn from his brilliant videos..Not just a salty bitter dude that makes videos to say “I know everything and u don’t “

[@highlandcycles]

That’s the goal

[@scottcoplin8322]

Great video Morgan, really appreciate the service you provide to the dirt biking community. You're a truly awesome guy. Cheers

[@highlandcycles]

I appreciate that!

[@spencerturleyfan]

I love how you dissect this new bike and study it 👍

[@CraigPaton-i9j]

Awsome video on the top end rebuild for ktm300xc2023 .I love mine it's the best bike iv had .Also love the Saltire in the background. I'm a Jock living in NEW ZEALAND These bikes are awsome for mx and xc.Cheers Guys.

[@genxgamerdad141]

Another one of your videos saved for future reference for my kids 2023 300xc. 😁👍 Thanks!

[@Dat_Sun]

Man this is super helpful, thanks for taking the time Morgan.

[@d.brayman3165]

Just like my home computer...when all else fails, unplug it. I liked how you explained the power valve process. Thanks.

[@highlandcycles]

Glad to help

[@mbrick]

The pistons look different. The relief on the intake side is a different shape? Thanks for sharing, been waiting to see a teardown on a TBI.

[@sweetvidzbyjoe]

28 hours on my 2023 TX300 TBI and the piston skirt shattered taking out the cylinder, power valve flapper, head, damaging plastic on crank and scratching up the cases. Seems like the OEM pistons are just touching the cases behind the crank/below intake track under high load and high RPM’s. I’d highly recommend replacing the OEM piston and/or doing top ends very often unless you’re blipping around. Cylinders and other parts are on back order till 10/31, and probably won’t come in till later… Glad your motor is in good shape, Morgan.

[@highlandcycles]

That sucks. I had mine wide open a lot. I got lucky

[@sweetvidzbyjoe]

Same, in sand, muddy sand and prepped tracks, so I don’t think it’s an immediate thing. Sounds like it’s only on some pistons and even then it’s not so egregious that it cracks right away.

[@mikemajor5291]

Thanks for making this! I went through the exact same power valve experience matching the motor to the power valve during reassembly. Fortunately I have a buddy that works at a dealer to reset the code but this is all great to know next time I do a top end and can avoid the code next time

[@highlandcycles]

🤘🏻🤘🏻

[@crjmoto]

Keeping my carb'd 2018 forever!!! 😄

[@highlandcycles]

Good move

[@philipsmith6152]

Another great mechanical review, awesome stuff 😊

[@madMX96]

Sherco uses electronic powervalve for years. I did top end on mine 20hrs ago, did not need to reset anything. Best practice is to change at least rings at 50 ish hrs to avoid cylinder wear and then rings with piston after 100hrs. Someone on FB pointed that yours was actualy running lean with too much oil and most likely with low compresion head.

[@highlandcycles]

Hahahahhaa. I run it at 40:1 and it’s hardly lean. The PV thing is definitely unique to KTM

[@csmith7693]

Cool! This is going to help!

[@mmaaddict78]

Good job!

[@christopherdavidson4706]

Great content. Thank you.

[@ryanstewart1521]

Great vid!

[@brianmullins739]

Another awesome video from Morgan The Man! Thanks bud. ❤

[@highlandcycles]

Glad you enjoyed it

[@craighoffman6876]

Really enjoyed this figuring it out in real time video. So in the end, the protocol most likely is to disconnect the battery to power down the system so the electronics don't "know" you are fussing around with the power valve. No big deal, and the electronic PV actually might just be easier in the end as it literally should be plug and play. The rest of the top end job is pretty much standard the way it has always been fare. Have ridden a '23 TBI, it is the first injected KTM two stroke that I like as much as my hairy old dialed in carb'd '18 300 XC. The TBI was on it's toes and ready to rip, it works like a perfectly jetted carb that has a tech riding along and tuning it as you go. To me injection on the new KTM 2Ts is finally worth it. Will I sell my '18? Nope. I buy new, get 'em how I like 'em, and then keep 'em a long time 😆

[@highlandcycles]

Agree

[@corsair7531]

Thank you for the videos Morgan!👍. As a past owner of ktm 250's and 300's and now a new owner of a 2024 Husky TX 300, I appreciate all of your time and effort you put into sharing your knowledge. Can you tell me what the difference is, if there is any, in the ktm cylinder and the husky Kymco? Thanks again.

[@highlandcycles]

I don’t think there is any dimensional difference but some people are saying the Kymco is not as good quality. I can’t speak to that personally but that is the prevailing rumor.

[@davidanderson2393]

Kinda weird on the piston deal, when I did the top end at 120 hours on my 18 XCW my local dealers KTM or Husky didn't have any pistons but on back order. Had to get my B piston kit from RM ATV, ran a deglaze hone and back in business, my RK head looked as clean as yours when I pulled it apart. Have a new 23 TX 300 now, it was interesting to see how the power valve went, less linkage and such looks good, still have my carb 300 for back up.

[@zachfarkash6430]

Dang Morgan looks like it was run and really good. Not bad looking for over a 100 hours on it.

[@evanmiller1642]

Only 100 hours. Morgan coulda run it to 200 like us lesser mortals

[@gman3725]

Have you looked at squish? Heard some TBIs have too much squish and require another base gasket which also improves port timing as well.

[@highlandcycles]

I checked it when I put the RK head on and it was good. I love how these bikes rev and wouldn’t want to lower the ports too much but I also love torque so I kind of shoot in the middle. I’ve ridden the bike since this (next video) and it is perfect

[@mmig2116]

Morgan you hear any problems with seizures on the xc 2023 models? Also any ecu issues ? I have a 2022 xc 250 now bike is great! I appreciate your videos thanks!

[@highlandcycles]

I haven’t seen any issues?

[@richardhartley1705]

Good job 👍

[@josevelez49]

Mine's on ly has 11 hours. But I am a little concern about of the piston to crank clearance. Did you checked that? I will probably just tear it down to check that and to put in a thicker base gasket to lower a little bit the compression. Those engine seems to be failing do to tight clearances!!

[@highlandcycles]

I have heard that but not had any issues

[@sparky_zap69]

Was trying to see what size piston I needed for my 24 300xcw tbi. Manual says the cylinder size stamp is on the right side of bike under power valve cover… couldn’t see it unless I had to start pulling the power valve apart to see underneath it which I didn’t wanna do at the moment . I could see a 01 on yours behind the left side cover/actuator… wonder if that’s the same?

[@highlandcycles]

Don’t know but could be

[@mark_Hershey]

Very curious of this piston skirt/crank contact I’ve seen pop up from time to time.

[@highlandcycles]

I hear about it but haven’t seen it

[@ryanstewart1521]

Is there supposed to be side to side play in the piston arm where it’s attached to the crankshaft?

[@highlandcycles]

Yes. There is an acceptable amount of axial play (that’s what that’s called). I think the max on a KTM 300 is about .026”

[@Springerfam2011]

Curious what the difference in the piston sizes are and how you know which one you need? I've got a 23 300xc with 60 hrs.

[@highlandcycles]

The difference is only .01mm between them. I just always go with a B. You should really measure the bore and match by clearance but I have never had a B piston not work well. It’s really hard to accurately measure the bore (especially on a 2 stroke) but if you are worried, a machinist will have the tools.

[@GNR325]

Hi Morgan. Loving the videos. Have you ridden the 250XC TBI yet? I'm shopping deals on '23 leftovers and only 250's left in my area. I hear more than one report where guys actually prefer the 250 for it's more free revving, playful and light feel. The new 300 sounds pretty free revving to me though. Are you hearing about any problems with these TBI models now that guys have more hours on them? Thanks!!

[@highlandcycles]

I haven't ridden the 250's yet but I am sure they are rad. I love the 300 because it is easier to ride in the hard stuff but the 250's are amazing. My XC-W was 250 at first and I loved it. And I have 150 hrs on my TBI and it has been perfect.

[@GNR325]

Thanks!@@highlandcycles

[@HVACOG]

Hey bud, do you recommend the 21-23 model or the 24? I’m looking at the xcw. First bike but I do have a little experience including a lot of single track mountain biking. Thanks for the videos

[@highlandcycles]

24 for sure

[@chief8269]

A friend of mine just had a failure on a 23, I guess the piston skirt made contact with the crank. Heard of this issue? He told me it’s a known issue, and a company is working on a solution.

[@highlandcycles]

Never heard of it

[@DavidMinkCCCMD]

I saw some chatter on vital about it but could find very little about it. I think if these were commonly exploding, there’d be a lot more chatter.

[@mark_Hershey]

Did you put sealant under the base gaskets at case halves?

[@highlandcycles]

No

[@bradleymuha4861]

What coolant do you use for your dirtbikes two stroke?

[@highlandcycles]

Evan’s

[@dirtbkr100]

what did the power valve look like? Did it need to be cleaned off?

[@highlandcycles]

It was great

[@panic-revv85]

Did your vertex top end kit come with a wrist pin bearing? My YZ ones never did so I switched to OEM for those bikes.

[@highlandcycles]

No, I had to buy that separately

[@letsridesingletrack]

Have you heard anything on the piston slap & people getting new pistons that have smaller skirt on one side so it won't contact crank. Wanted to find out if there was any merit to that stuff going around on the 23/24 300 TBI bikes having piston slap against the crank at high RPMS. I have a 24 300 and haven't noticed anything off.

[@highlandcycles]

I have yet to see any of that. I think it bs personally

[@michael397]

Hi Morgan, this new model starter motor changed or still same as before? repair the starter motor is really painfull 😅

[@highlandcycles]

Seems to be the same

[@michael397]

@@highlandcycles thank you!

[@WillyD1]

I got the vertex top end gaskets came with the top end kit are those any good some people saying use oem

[@highlandcycles]

I like them

[@jbclockpicker]

why do you have used a B piston? did u measure the Zylinder before you ordered the Piston ?

[@highlandcycles]

No, I always go with a B for the first replacement. It’s only .01mm bigger. It would work just fine in a brand new OEM “a” cylinder.

[@Wooskii1]

How do these TPI and TBI bikes compare to the carbureted bikes? Is there any advantages besides convince, like power or longevity? I just got a 2018 carbureted 300 XC-W because I'm not familiar with F.I. 2 cycles (I'm not familiar with KTM either) but I've always wanted one. I love it already, but it needs a top end (120 hours, seems fine). I plan to pay the man to do the first one and give me a good baseline, go over the bike, etc.

[@highlandcycles]

Carb bikes run great and don’t have weird problems

[@Wooskii1]

@@highlandcycles I feel much better about my choice if weird problems is all you get with FI. I'm familiar with 2 cycles in general, mixing in some oil isn't a problem, and I can change the jets if I have to. Kick start backup is also nice.

[@jimstrieby4998]

So...after disassembly and inspection, things looked rather good. what was your fuel/oil ratio leading up to this top-end? NGK BR7ES?

[@highlandcycles]

40:1 and yes on the plug

[@SpeedDemonExpress]

​@highlandcycles why 40:1? Do you have a tuner to add more fuel to make up for that? Because that will make it run a little leaner and ktm already has these running lean on 60:1. Now you have even less fuel at 40:1

[@highlandcycles]

@@SpeedDemonExpress not true. These bikes are crazy rich on the bottom. That is why so many people are fouling plugs.

[@txkid123]

Morgan, I’m only at 25 hours on my TX300 but thank you for this reference video! When you remove that left side power valve actuator and set it on top, does it have to be timed when reinstalling? Or when reinstalling does it only go on one way? Thanks!

[@highlandcycles]

Did you watch to the end

[@txkid123]

@@highlandcyclesI did, and I saw the dongle procedure. I’m curious as to the physical connection of the actuator to the power valve itself. Is it a round gear that goes on either way or is it notched so that it can only be installed in one position?

[@highlandcycles]

@@txkid123 oh, sorry. It’s a slotted shaft on the actuator. So theoretically it could go on 180 degrees either way.

[@txkid123]

@@highlandcycles thank you Morgan! Appreciate all you do for us.

[@Enduroknightryder]

Did you switch to the BR7ES to make it not so gummy? Mine spooges like crazy out the tailpipe. And im at 55:1. Also whats the brand of hone you use? I just use the flex hone i got off rocky mountain. Is that a "good Quality" one like the one you used? Just curious, thanks for your funny videos!

[@highlandcycles]

Snap on hone. 7 plug because the 300’s always ran them in the past.

[@PatrickRiggs33]

Hey Morgan, how did you know to go with a B sized piston vs. the A?

[@highlandcycles]

I always do on the first top end. The difference is tiny and the B always fits great

[@175nofear]

When the power valve motor insert isn’t in line with the power valve arm you just put your finger in the exhaust port and push or pull on the power valve to align it. No need to pull out a dongle or any of that. Just fyi

[@highlandcycles]

Good to know

[@tkrey23]

slight difference in the intake port shape on the piston you can see at 9:11. the new piston you got - is that from a carb'd 300? The TPI bikes had more of a square intake port and wouldn't run quite right with the carb piston. I think the TBI piston looks closer to a TPI piston than a carb piston... but I had 250's which had same port shape for carb/TPI so not as familiar with the 300 port shape. I know it's a thing though.

[@highlandcycles]

Yeah. I’m not sure. The new piston is a vertex that fits a tpi based on their website.

[@tkrey23]

Gotcha. Then that's the more square port shape compared to the carb. Looks like they made it even a little more square for the TBI

[@rickypelz8345]

What mix and ratio do you run ?

[@highlandcycles]

40:1

[@brandonatchley5221]

Which ktm piston was that from? TPI old 300? Or 17/18 carb 300

[@highlandcycles]

TPI

[@Dkjg0000]

New 2024 gagas 300ec has engine light with 5 blinks , Just done tps adjustment and power valve reset unhooked battery negative and reset power valve again still can’t get rid of engine light any ideas how to clear it without going to dealer

[@highlandcycles]

I don't. If it is only on at idle then it is a historic code and won't effect anything. If you get the TSP ERM you can clear codes yourself.

[@DavidMinkCCCMD]

Have you heard any chatter about the rear side piston skirt contacting the crank halves and breaking the skirt on the 300 TBIs?There’s a few instances of people talking about it on vitalmx. Not sure if there was anything to it or just poppycock.

[@highlandcycles]

Have not heard of that personally

[@DavidMinkCCCMD]

@@highlandcycles seems to be very few and far between. I have 19 hours on my 2023 300SX that’s all hard motocross and it runs like a top.

[@highlandcycles]

@@DavidMinkCCCMD nice.

[@mark_Hershey]

Wow, you got 120 hours on the oem piston? Thanks for the vid..

[@highlandcycles]

Yep. I’m shooting for 150 on this one. I’ll be there soon.

[@mark_Hershey]

@@highlandcycles good deal, I’ll be watching. Was just looking at the manual and ktm calls for piston change at 15hr…

[@jyoung6708]

I came here because I did a top end and had the same issue with the power valve and I put it on the exact same way with the “cheat code”. I haven’t unplugged the ECU yet though. You’re doing the top and did you notice it running more rich than normal? mine is running like a turd.

[@highlandcycles]

No, it ran great. I think you should do the un plug the ECU thing and get the codes to clear. If you haven't done the most recent map update you might need to so that unplugging the ECU will do something.

[@jyoung6708]

@@highlandcycles so I had it in the shop last week and they cleared the codes and numerous other things we’re done but was still the same. But today I took it back in there they reset the knobs and re-calibrated the TPS and this time it worked.!

[@highlandcycles]

@@jyoung6708 nice!!!

[@jonsainsbury8726]

No codes on my YZ250x..lol

[@painsrides]

I had base gasket leak on the rear cylinder of my Victory....Now removing those cylinders is a top end job, I never want to do that again. 😐

[@highlandcycles]

Ugh

[@builtfordtough4499]

So it's OK to run all the filings from the hone through the power valve?

[@highlandcycles]

Yes, as long as you clean it and blow it out really well.

[@highlandcycles]

I should have mentioned that in the video

[@builtfordtough4499]

@@highlandcycles I would have to disagree. The likelihood of you getting all the dust particles out is very low. 2 strokes also do a little thing called reversion. What that means is all those microscopic particles get pushed back into the cylinder.

[@highlandcycles]

@@builtfordtough4499 I am sure you are correct that not All of it gets out but what is left is so very small. I always take customer cylinders apart but on mine I do it like this every other time and I’ve actually never worn a KTM cylinder out or a piston before it’s time.

[@iddddaduncan]

What 2stroke oil do you use in your gas?

[@highlandcycles]

Motorex

[@scottphillips445]

You can order the optional circlips from ktm that are easier to install.

[@highlandcycles]

Yep. Fit the old 380’s

[@scottphillips445]

And thanks for the insight. I appreciate your channel. It would be an honor to take you out on the start of an off road race! Especially if we both traveled a long distance to the event

[@MitchOfCanada]

step 1- disconnect the Battery. Saw some funny wannabe mechanics with ADHD go from doing a top end to grips and hit the starter while the cylinder was off, in return destroying both cases. was the best thing i saw all year.

[@highlandcycles]

Holy crap

[@DannyDifalco]

Did you measure the X distance or did you just put in the same size base gasket? If you unplug the battery before disconnecting the power valve module it shouldnt set a code or move. KTM does state anytime the head or the module is removed the pover valve end points should be reset with the dongle. And if you removed the power valve assembly you should set the Z distance before setting the end points.

[@highlandcycles]

If you watch to the end I talk about the battery thing. I honestly don't measure all of that stuff when I am just putting a new piston in. I get the base gasket that is close and put it back together. I don't change anything on the powervalve. They always run just like they did before the top end. I have broken this in and it absolutely rips.

[@loopeyshooter503]

Do you ever double check piston to cylinder wall clearance or just trust they are correct?

[@highlandcycles]

I quit doing that a long time ago because it was never off. I checked and checked and it was alway on the money.

[@evanmiller1642]

Do wossner or cp offer a piston for that or whatever 300 that vertex is for. Whats your reasoning for going vertex? Was oem vertex coated? If it was it wore off thats surprising. 300s rocking that much? I just looked it appears vertex 2 stroke pistons are cast 4 stroke are forged. Ill have to do some more research on this if it is cast or forged. It doesn't matter a ton forged for is just alittle peice of mind on long intervals

[@highlandcycles]

Stock is vertex. Not sure if it was coated but I bet it was. I think it was rocking a bit towards the end. Definitely had some slap when you would beat on it.

[@evanmiller1642]

@highlandcycles Thats crazy for a long piston to rock that much. I wonder if the vertex pistons arent coated to reduce oem costs. I just about cant beleive all the coating would wear off in 100 hours.

[@highlandcycles]

@@evanmiller1642 yeah. I don’t know. I should have taken it apart at the beginning

[@milosbgd]

Great that its ELCO !

[@highlandcycles]

Yep

[@richardhartley1705]

What size base gasket did you use

[@highlandcycles]

Not sure exactly. I always grab one that is in the middle-ish. In my experience (which you know is large) it doesn’t really matter much.

[@Mostviews111]

Why does the factory cylinder have silicone on the base gasket?

[@highlandcycles]

Not sure.

[@Blockedinsight]

I’m curious how long can you get out of a Top End on a 2 Stroke? Is it normally 100 hours or does it depend on how you ride it??

[@highlandcycles]

Depends. But on my other 300’s I’ve always gone to 150

[@Blockedinsight]

@@highlandcycles That’s good to know, do 2-strokes need more top end rebuilds than a 4-stroke? I’ve seen so many mixed answers but I wanted to ask you, I really enjoy your channel by the way!! 💯

[@highlandcycles]

@@Blockedinsight in my opinion, you should do them both at about the same interval. People get longer out of the 4T but I think it’s a gamble.

[@Blockedinsight]

@@highlandcycles That makes sense, maybe it’s because of a 4T being more expensive for a Top End vs a 2T?

[@highlandcycles]

@@Blockedinsight yep

[@MechShark]

Morgan, what do you think of grumpy Jeff's EZ clips for the piston pin? Those things are always a nightmare for me as a DIYer. I was also thinking of getting some traditional wrist pin clips. Any reason Vertex makes these an unholy nightmare?

[@highlandcycles]

Those ez clips are great. Just so you know, you can get them from any KTM dealer. They are the clips for an older 380 KTM. Here is the KTM part number 54330074000

[@MechShark]

@@highlandcycles Nice, grumpy boycott!

[@highlandcycles]

@@MechShark Hahahah

[@fattie2550]

What does your shop charge for a top end on a TBI 2 stroke? Rough price.

[@highlandcycles]

400 labor plus parts. Usually ends up being around 700 with OEM stuff. That includes complete cleaning of power valve too.

[@fattie2550]

@@highlandcycles Thank you

[@Rangitatahunter]

Another vote for YZ for the average guy (who does not get a new bike every other year) I never want to deal with having to go to the dealer, blinking codes, lost my dongle or any other electronic BS. Dirt bikes are supposed to be simple, light, loud and fast - my 10 year old Yz will go to the boy next year and probably still be ripping in another 10 years, the way KTM is moving along, I bet the TPI bikes will be bricked inside 5-7 years with no electronic parts or sensors availability, and these ones which seem to be even more complicated - who knows?

[@highlandcycles]

Yep. Agree 100

[@Superdisco199]

I think one of the main issues you'll see is that the 2nd hand market stops absorbing really complicated bikes. A young bloke with limited cash and knowledge can't really troubleshoot a TPI. This means new bike buyers will take a bigger hit on resale and update less often. Poorly thought out by KTM...

[@yamahakid450f]

Unhook the battery before messing with the power valve, it'll stay put, if you don't it won't line up when you put it back on. Then do the power valve reset, I also do the TPS reset, which is using the dongle and give it 3 quick full throttle turns letting it snap back each time.

[@yamahakid450f]

Never mind, you were already told at the end lol but yes, it does work.

[@Mostviews111]

All you have to do is not put the covers on the power valve so you can torque the nuts.

[@SpeedDemonExpress]

Those pistons are different. The new one for the older 300's has a much wider notch on the bottom of the skirt. It probably has a different weight too. And the pin location could also be different, that could really mess shit up.

[@highlandcycles]

Been in there for 60hrs and runs great

[@RobertMoto10]

why for tpi the A rate is 71.925 and for carburation 71.94, can I put 71.94 in TPi?

[@highlandcycles]

Yes

[@RobertMoto10]

why is it 71.94 for carburation and 71.925 for tpi?

[@highlandcycles]

@@RobertMoto10 not sure. Could be that the tip’s are so lean they expect the piston to expand more

[@rposton919]

Started with small engines 47 years ago. Some things should always be torqued. Working with a AA rider 25 years ago, somebody that came by always wanted something fixed. Guess what, EVERYTHING was overtightened to within an inch of its life. Nothing but problems. Learn what should be torqued, and torque it. Always disconnect a battery before unplugging someting.

[@highlandcycles]

I have never had any issues with things being too tight or not tight enough after enough years of doing this. The battery thing, I just forget about these new fangled things. Fortunately my ability to reason and figure out problems worked out and its all good.

[@josevelez49]

Did you noticed that the window port on the new piston is wider than the old one? 9:14

[@highlandcycles]

Yeah. Little bit. Hasn’t made any difference

[@jeremymullen5378]

🔥👊🔥⚙️🏍🔨

[@highlandcycles]

🤘🏻🤘🏻

[@rztrzt]

These things have more wires than a 80s Toyota Corolla...

[@highlandcycles]

I know. But way less than the TPI bikes

[@ronhartle3268]

What the heck is zack beating on?

[@highlandcycles]

Who knows.

[@ronhartle3268]

Machinist handbook says a torque wrench is only 10% more accurate then feel.

[@highlandcycles]

Agree

[@200xcBruce]

I don't. I see you still don't like to check deck heights.

[@highlandcycles]

Nope. No need Bike runs perfectly