Motorcycle Top End Rebuild 4 Stroke (Part 1 of 2)

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Piston and Ring Replacement on the KTM RFS motor. Rebuild the top end on your 4 stroke atv or motorcycle. Piston change. Find all your dirt bike rebuild needs at Get Ready.

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Title : Motorcycle Top End Rebuild 4 Stroke (Part 1 of 2)
Video Length : “07:33
Channel | User | Playlist : Rocky Mountain ATV MC
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RockyMountain MC

RockyMountain MC

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  • never in all my motor rebuilds, or watching someone else rebuild motors have a seen someone take a link out of the timing chain to remove everything, you just loosen it and take the stuff off??? making this way too hard on yourself

  • I seriously doubt that most states have any trained/experienced motorcycle mechanics who could do this sort of work effectively and well. I can’t, but then again I don’t claim that I can nor am I a mechanic. There are factory-authorized shops that claim to be able to do this sort of work, but through conversations and low-level repairs … I’d be very reluctant to trust them. I do all routine maintenance to keep my RSTD in good/safe condition … brakes, all fluids, air and gas filters, plugs, bulbs, etc … but beyond that my only alternative will be bury it.

    • On some bike it’s not necessary when replacing the top end, but for this bike you do need to drain it as one of the first steps. It’s always a good idea replace the oil when you do any engine work so you may as well drain it before you start tearing into it.

  • Hello guys, There is little oil leaking from the gasket (metal one) under the cilinder. But I have a LC4 KTM 625 2005 (grey engine). It looks similar to this toturial. Can I expect some other things/parts to pull off??

  • Great video, this is really swaying me to try and tackle this on my own.

    Question. Why did you split the cam chain, I think I’ve seen other videos where you just move it out of the way after its loose?

    I have an 06 450 exc-g usa, can you recommend a rebuild kit with all the necessary gaskets please?

    It’s hasn’t been rebuilt since I’ve owned it for the last 4 years, I do mostly street riding now, anything else I should look out for while I’m in there?


    • +anders melen On this particular RFS motor you need to break the cam chain in order to get the camshaft out. For a top end gasket kit, any one of our kits that we offer will supply you with the necessary gaskets to rebuild your KTM. I’d recommend keeping an eye on all the little parts in there and basically following this tuturial video and you should be fine. Thanks for watching!

  • Thanks for this video and your support of our local Colorado Supermoto club. I appreciate and use your sponsorship race gas gift cards! On removing the cam chain, can I use my trusty drive chain breaker tool to do the job or is there something special about the CAM breaker tool? Thanks again!

    • +Clayton Jacobs The Race Gas Program is awesome! That’s good to hear you’re taking advantage of it. The drive chain breaker tool i don’t think it comes with the correct size pin to pop a Cam chain pin.

    • +Clayton Jacobs First off what bike are you working on? It will be more of a case by case adjustment. For most applications and the average rider you should be fine running with the stock settings but you may be able to suit a bike more to your riding style and preference if you domake adjustments. With the higher compression piston you may need to up the octane rating of your fuel depending on what you are running. If you have any other questions let use know!

    • +Rocky Mountain ATV MC
      Thanks for the reply. I am working on a 2006 KTM SMR like in the video (RFS engine.) I did choose a high compression piston to still be able to run on pump gas at 5000ft elevation. I am racing supermoto in the Novice class so I do anticipate riding hard. Not so hard that I want to squeeze every HP out of it at the cost of significantly more difficult tuning (ie spark tuning) but I have added a wide band O2 sensor in the exhaust so I can at least get my jetting spot on.

    • +Clayton Jacobs Sounds like you’re on the right track! Running higher octane gas would be an easy way to get more horsepower if you end up wanting more later. If you have any other questions let us know

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