How To: 4 Stroke Top End Rebuild | Motorcycle Superstore

Changing the piston, AKA top end, on your modern four stroke motocross bike is easier than you think. With the right tools and a bit of know how (thanks to Gregg Albertson) you’ll be able to get the job done in your garage at home!
Find the tools, supplies and the step-by-step instructions here:bit.ly/1Vr6oNM
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[@trumanhampton1845]

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

[@John_Doe_6996]

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

[@mattwarrensocal]

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

[@ManicalGamers]

I get that 😂

[@JC-gy5bh]

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.

[@skynjaydensdaddy]

I believe he said it'll be a quick basic overview 0:13

[@Trap..house.]

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

[@mxcollin95]

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. 🤙

[@ApalconJudo]

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

[@MaximmixaM100]

WOW nice rebuild thanks dude ;)

[@charlotteglove5066]

Great vid short simple thanks

[@ColKurtz-pi1ku]

Well done!!

[@TheBaaHA]

Great video!

[@scottmorgan6099]

Cool maintenance video,...👍

[@GooberNuf]

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

[@thomasharrington4146]

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

[@steroidjunky9394]

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

[@danielvonhoene2666]

how’d it go

[@danielvonhoene2666]

how’d it go

[@Moto-411]

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

[@alfred7136]

Depends on the bike, sometimes you only have to get the tank off the bike and the rads.

[@Moto-411]

well that my first top end full rebuild was not that difficult :D only device take your time so you don't need to go back a step or 2

[@CR-rb2sr]

Yeah shit video

[@anthonyw1380]

good video

[@AmrinderSingh-zx9hr]

Very Good Knowledgeable video

[@jdubbs21]

Thank YOU!!

[@howtohermione2]

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

[@StinkyWeiner]

Looks easy enough

[@ivanmanuele2542]

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

[@peterpedant]

Im gonna go ahead and try this myself.

[@Professionaltrenchdigger]

How'd u make out?✌️

[@dylanrooney5772]

What about getting the bore machined???

[@helipilot727]

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

[@codcade]

I did every 10 hours on mine lol, I traded it and the kid I gave it to put about 200hrs on the same oil and threw the rod through the bottom of the case

[@G_Rapids]

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?

[@sssereno5252]

Thanks

[@timetter7062]

oil looked brand new lol

[@StevenStGelais]

He did said change every few days😂😂

[@tylercassidy1230]

When you install new cams you have to change oil to petroleum based

[@jimsvideos7201]

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

[@michaelprata8135]

wow I just lost my shit seeing him do that lol

[@Foxbodyguy91]

You don't say

[@W2TW]

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.

[@MrOrangecrush1234]

Where can I buy that flywheel tool

[@G-T-S-J-FAMILIE]

Do you stil have the raceteam

[@lionelkantor1134]

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

[@masonweddle980]

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

[@Insanity_420]

Is that a kfx 450r engine?

[@pseudoprodigy]

You let the cam chain drop?

[@adamflynn7322]

is this an rmz 250?

[@lucasdonoghuemcewan]

What tools do you need to complete this?

[@Crazyhero-zi6yt]

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

[@jamienichols6277]

TDC is TDC either way.

[@gmannfram8682]

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?

[@rod1m]

Well this convinced me to buy a 2 stroke 😂

[@YaseenAli-zn9ej]

Two strokes are better anyways in terms of raw emotion and power

[@bikelifemar3494]

Two strokes more work you lazy for a 4 stroke

[@JayDeeFrm7400]

Rebuilding 4 strokes ain’t that bad once you do it a few times

[@JayDeeFrm7400]

@@YaseenAli-zn9ej 4 strokes are more torquier and the power is smooth unlike 98% of 2 strokes will bog down if you gun on throttle all at once unlike a 4 stroke where the throttle is more responsive

[@YaseenAli-zn9ej]

@@JayDeeFrm7400 4 strokes are far more expensive to maintain, they might be fun but not nearly as fun as 2 strokes. Also with a lectron carb, a 2 stroke would have linear power and won’t bog. They are also faster and sound cooler imo. I just prefer 2 strokes due to the simplicity and fun.

[@brandenbatalla5329]

know that is a great ass video

[@magoogers6412]

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

[@likearni1062]

Magoogers I usually lay my bolts out in the order I took them of. Or you can put the bolts in to different containers to keep track of what goes where. Usually you can kinda guess where the bolts goes to, by making sure the threads match

[@spivzespivatron6712]

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

[@scallie6462]

Spivze Spivatron at TDC the CAM LOBES should be facing up, ie not in contact with the buckets.

[@Crazyhero-zi6yt]

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

[@pseudoprodigy]

Crazyhero 1924 look at the crank rod..

[@themuffinman8871]

where did you buy the engine stand?

[@justsourcerawsource6915]

The Muffin Man Just the thing I am thinking and looking for

[@CharlesSchuckIII]

I was thinking the same, Found it here: kzbin.info/www/bejne/oIi2ga2lirVgn68

[@tinnytomcat]

Wow I thought there was a lot more to it

[@chrisvlogz6206]

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

[@doubleclutchinjammingears3391]

its Chris yooo lmao.. 100 hours is right, but you ain’t riding more than 5 hours a day doing wheelies. And you prolly aren’t riding everyday, because that shit is illegal to do on roads and you’d have to lay low every couple days to not get busted. Unless you have private property, or a road legal bike. So say you ride normally 4 days a week.. that’s 20 hours. That’s over a month in between rebuilds, and you should definitely get an hour meter. If you buy a motocross bike for wheelies, expect motocross bills. Street bikes are cheaper to maintain.

[@chrisvlogz6206]

@@doubleclutchinjammingears3391 thx

[@jaredallen8054]

This is Ronnie macs brother everyone

[@jadonkirk5930]

Forgot to mention to do ring gaps

[@jacksonholland9790]

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

[@gabrielshultz5872]

Depends on the bike you are working on. Have to look them up. He didn't say a specific number for that reason. Your situation is likely different.

[@renosnutzz8592]

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

[@DSFiveO]

And this is why i have 2 strokes. 🥵🤣🤣

[@melissawillis3398]

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

[@maxbeazley499]

the piston would be worn out, and will need a top end rebuild! will cost around 140 to 200. good luck! 2 stroke or 4 stroke?

[@meikeberle5848]

Brand new oil lol

[@flipsidedfilms3758]

He dropped the cam chain

[@TrippyBlue25]

Can you rebuild my 125 4stroke engine

[@ShahabLodhi]

honing boring..??

[@mikesoliz7097]

I learned from this video is to pay a professional

[@dancampbell6958]

Bro said change oil every few days?

[@jakej7493]

Acts like a professional doesnt even check ring gap.

[@WesTheDeal]

Learn how to properly use a torque wrench...

[@helloperson1229]

John 3:3 Ephesians 5:4 in the Bible

[@joshypoo2006]

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

[@chinobecatchingbloxx836]

Who’s els bike just blew

[@mohammadshahin4922]

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

[@joshstewart1226]

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

[@dougiequick1]

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

[@spicketspaghet7773]

Having an actual removable timing cover on the side of the engine would make things way easier.

[@dogger2186]

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.

[@TOMVUTHEPIMP]

You have no fucking clue.....