How To Rebuild the Top End on a KTM/Husqvarna/GasGas 250 & 300 2-Stroke TPI

Whether you blew your bike up, are having a loss of performance or just want to refresh your engine for the riding season. Rebuilding the top end on your KTM 250 or 300 TPI is a great way to get familiar with your dirt bike and prevent catastrophic failures in the future. Knowing how to do the job correctly will save you tons of time and money compared to taking it to a shop. In this video, Charles shows how to rebuild the top end on a 2021 KTM 250XC, but this process will be similar for KTM, Husqvarna and GasGas 250 and 300 2-stroke TPI motorcycles.


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[samadventures]

This video is aweosme I’m 14 an rebuilt my 2019 Ktm 300 exc all on my own Whatching the steps of this very detailed video 👍🏽👍🏽👌🏽

[jimg]

Great video Charles! EXTREMELY helpful to a guy who has not done a top end rebuild for 40 years!

[mattcollins]

These are the best videos on the Internet.

[batipapo]

Excellent video with all the detailed yet concise. Them circ clips look more like a puzzle.

[anthonystruik]

Excellent video Charles, thank you. I just wish that inserting the piston circlip is as easy as you make it out in the video.

[MikeHughesShooter]

Thank you. Excellent work. Ordered kit from you because of this video.

[coffeeinthemorningsun]

Thank you for this perfect and detailed video 👍! Greatings from Germany!

[DYLLY]

That’s crazy how you can get those clips in without scratching the piston at all, i did the top end on my 250 yesterday and scratched my piston on both sides🤦‍♂️ wish I had seen this video first that trick with the screwdriver would have made everything so much easier haha

[RICHIE_RICH]

Start it up thats the best reward for pete sakes

[ChrisKAloha]

Set the z before you put the cylinder on the bike. And if you don’t loosen the jam nut set screw you don’t have to reset it.

[jakemassa]

Awesome video! I’m wondering, what steps are different when performing a top end on a 150 TPI?

[JMcCart]

Shouldn’t you have added coolant and let it bleed through the temp sensor before putting the tank on? (I’ve done it with the tank on also)

[corysargent]

Question: is it wise to run the oil relay to actuate the oil pump before the first start?

[motosz]

The retaining washer for the control valve in this video is triangle shaped. This is different that what is in the KTM exhaust valve blueprint which shows retainer plates instead. Where can these retainer washers be found?

[Jeff-pczu]

I would say this KTM is actually "oil injected" as opposed to fuel injection like the TBI is. If and when the oil pump goes this bike will seize up! TBI is a much better option as you still put oil in the fuel.

[human]

Great video in many ways. Thank you for making it.

[tuckeradams]

i wish you wouldn’t edit out the parts where you struggle. it makes it seem like it should be easy as pie when in reality it’s not that easy u just edited it out. be transparent shown it all!

[paulinebeckett]

Great video Charles but the only quality part on that KTM was the NGK Plug.

[jimbo]

My dad showed me how to rebuild a 2 stroke on my 78 Yamaha it 175 . I was 14 and she was running great afterwards

[henning_]

Please Help me: I cant torque the spark Plug because the cumbustion camber spins. What can I do?