How-To: KTM 250 300 350 380 SX MXC EXC Top & Bottom Engine Rebuild 2003-2015
Here are two new videos for you 2 stroke guys out there. The top end video covers piston & ring replacement, power valve maintenance, and runs 1 hour 10 minutes long! Bottom end video runs 2 hours 50 minutes long and covers crankshaft and transmission disassembly and reassembly.
Don’t pay a shop $80+/hr when this is a job you can totally handle yourself. I’ll walk you through the process step by step in this easy to follow video tutorial. Have a question? I’m here for email support every step of the way.
Service Manual
I found a cool website that has several KTM service manuals available for free. Please help support this site by hitting the donate link at the top.
Tool List
Here is a complete list of special tools. Most can be bought from Amazon.
Motion Pro 08-0008 Clutch Holding Tool – Holds the clutch basket while loosening/tightening the nut.
Motion Pro 08-0427 Gear Jammer Tool – Jams the gears allowing certain fasteners to be removed/installed. Super helpful since it has a magnet to keep it in place.
Motion Pro 08-0026 Flywheel Puller M27X1.0 L.H External Thread – You will need this puller to remove the flywheel.
Tusk Crankcase Splitter – This tool was not needed to split the cases. However, it does serve a way to press crank out from RH side.
BOA BO13010 Constrictor Aluminum Strap Wrench – This tool is awesome for holding pretty much anything. It’s aluminum body and rubber “grippy” strap makes it a solid tool.
Lisle 56750 Seal Puller – Nice tool to remove seals.
Impact driver – I have the Vessel 2500 which has been discontinued. Click here for the Vessel page, they have a newer version and sell JIS bits.
IR Temp Gun – Great tool for measuring case temperature.
Assembly Lube – Lube it up!
Moly Grease – Some areas call for Moly.
Three Bond Liquid Gasket – I used Hondabond. This Three Bond is pretty much that same stuff.
Part List
If you have an OEM crank, it would be best to send it out for a rebuild. Since the stock crank was long gone in this bike, we are replacing the Hot Rod crank with a new one. Hot Rod costs a fraction of what the OEM goes for.
Hot Rod Bottom End Kit CBK0006
Vertex 23375B Replica Piston Kit
Comments
Has this video helped you? Please comment below.
I bought the video and I can’t seem to find it anymore it’s asking me to pay what do I do?
I will email you.
I purchased the ktm top and bottom videos, and now getting a error when trying to play any of them
I sent you an email. Please respond.
i wanted both videos top and bottom I have the top but will not let me purchas bottom
I will refund the top end video. You will have to purchase again, this time select top & bottom video version.
Matt
Do you show bearing orientation? ie. which side/direction the numbers are facing when installed correct?
Thanks
I dont’ recall that info being called out in the service manual. I believe most bearings go in either way.
Either way, the video follows the service manual procedure, and was assembled correctly.
It doesn’t give me the option to purchase the video
Here is the direct link: https://gum.co/ktm250
Do you have top/bottom rebuild tutorial for 2015 sxf 350. It’s says 250, 380 and 300. Thanks
I don’t have any vids on that model.
Is the Top and Bottom Engine Rebuild video still available? I don’t seem to be able to purchase it.
Here is the direct link: https://matthewmcrepair.gumroad.com/l/ktm250
Does this bottom end video work for a 2003 KTM 250 SX?
Yes