How To: 4 Stroke Top End Rebuild | Motorcycle Superstore 

Best top end video I’ve ever watched I feel confident enough to go ahead and go through my top end everyone else makes it seem so complicated this guy really made it simple and easy

You made this look very easy. My top end kit came in the mail today. Hopefully my bike starts when I’m done!

This was an EXCELLENT, EXCELLENT video. I know this video is a little older but all the info is spot on. PLEASE consider doing more 450 engine building videos as I’m sure they would be well received and appreciated! Thanks for posting. 🤙

Nice to see a video without 14 parts of 12 to 25 minutes each. Thank you for a concise vid!

I wish this was a lot more specific, like walking me into every single step. Got lost a few times, didn't exactly gave me the courage to do this to my own bike.

Grate video especially for a mechanic that has not done a top in in a few years thank you !

Great video! Thanks for the quick overview and general recommendations. Referred to User Manual and other video's for detailed specifics.

WOW nice rebuild thanks dude ;)

I tried taking the exhaust of my rmz250 and ended shattering a spanner.. the exhaust is there forever now.

I'm about to do it for the first time new to riding so yeah first rebuild. Appreciate the video man love lurning all this stuff

Great video!

Great vid short simple thanks

Well done!!

Cool maintenance video,...👍

hello is it possible to make a video to change also the connecting rod and the main bearings? thank you!

Very Good Knowledgeable video

Why do you need to be on TDC for the removal? You moved the crank all over when you were removing the flywheel. Is this a common practice?

Thank YOU!!

What about getting the bore machined???

So what was done to the top end? Piston, head gasket and chain was the only things replaced. I figured a top end rebuild would be focusing on cams and vlaves. but I have no idea.

Where can I buy that flywheel tool

I have an 08 rmz250 I cant get my exhaust side cam chain GUIDE to go in correctly its just a hair to high so my exhaust cam won't sit in head correctly. What am I doing wrong? PLEASE HELP

Do you stil have the raceteam

Well u made that look easy hell thanks for the vadio..

right i am rebuilding my engine this weekend no mention of honing cylinder no mention of piston ring and how to install them not showing how to remove valves how to shim properly just to get a topend rebuild you basicly need to take apart half the bike

Hola con cilindro en buen estado. Cambio de piston requiere bruñido si es asi con que grano de piedra

good video

Is that a kfx 450r engine?

What tools do you need to complete this?

You let the cam chain drop?

don't forget to install the 2nd circlip on the piston before putting on the cylinder

is this an rmz 250?

Thanks

Im gonna go ahead and try this myself.

Looks easy enough

You put new piston rings in the same cylinder? shouldn't you of honed it? take the old polish out of it? So the new rings could seat in/? that motor looked fresh and the oil clean as can be. hmmm?

What are cam keepers? How do I know that its at ignition tdc not exhaust tdc, without the marks at the head?

How do you keep track of every little nut and bolt and where it goes?

what if the pistons siezed in the barrel?how do i know tdc is right on the valves?is there a mark or something?

How do i know that the flywheel is on tdc if i removed it before? Is there a Parallel Key?

know that is a great ass video

You drain your oil every few days? HUH? Maybe this is referring to a full time race bike.

If a breaker bar isn't a torque wrench then a torque wrench isn't a breaker bar.

where did you buy the engine stand?

Ight how often do I rebuild the top if I'm only buying a dirt bike just for wheelies cuz I'm looking at forums and its every 100 hours which roughly 4 days. I don't wanna assume that's right and that's final cuz I'm not tryna rebuild a motor every 4 days. If I spend 4 days out of the week riding, every 5th based on that rebuild day. Someone steer me in the right direction please

oil looked brand new lol

Wow I thought there was a lot more to it

Forgot to mention to do ring gaps

What t wrenches is he using those aren’t the lame ones

What exactly is manufacturer spec? Why don’t you tell us what the specifications are while torquing down the screws? Would make things a lot easier

Well this convinced me to buy a 2 stroke 😂

This is Ronnie macs brother everyone

Can you rebuild my 125 4stroke engine

Bro said change oil every few days?

need help my bike was working fine and just stopped , now it has no compression

honing boring..??

He dropped the cam chain

And this is why i have 2 strokes. 🥵🤣🤣

I learned from this video is to pay a professional

Brand new oil lol

Acts like a professional doesnt even check ring gap.

Learn how to properly use a torque wrench...

Did this guy really use a torque wrench to loosen head bolts... wtf

Meanwhile 2stroke: remove top end and replace piston and install new gaskets....

Who’s els bike just blew

The complexity of rebuilding a top end sucks. It seems to me the manufacturers would make it possible to yank the entire top end without dissasemly, in other words engineer a super easy means of disconnecting the cam chain or other means of camdrive (that IS possible obviously even I mean even if you have to drive the cam from the outer end of the shaft) then one simply pops off the plumbing and the cylinder base nuts and yanks the entire thing to be shipped off to the rebuild company at which time you pull your alterate top end from it's box install the new piston that came with it slide the new top on and replace cam drive and plumbing DONE...on the other hand the moment electric MX bikes are totally perfected? And they begin winning like crazy and cost less than IC motors? Andvenues open that ban IC bikes because of the location (noise and indoor air quality reasons for instance) Then at least for motocross piston engines will become relics while racers no longer need to be either amechanic or rich enough to regularly pay one

John 3:3 Ephesians 5:4 in the Bible

you skipped some shit i dont like that, i like a video for something like this to show me every step the technician does

Come on please...no oil in the cylinder.... Hone the cylinder and clean to good with contact cleaner Oil only the pin and clips (assemble everything else dry.) This really lets the new rings byte and seat. Fire it up and run it until it pukes and your ready to rip! I have done 5 top ends with great results. Test for yourself. Assemble a Top end with Oil and keep all the parts. Then your next one assemble dry only lubing the pin and clips. Then at your next top end compare the 2 pistons and the 2nd top end will look much better.