You can usually take each shaft out without removing the gears, but be careful not to let them slide off the shaft as you’ll never remember how it all goes; unless you have a manual of course.. Removing the nut will require your clutch basket holding tool, these tools grip the clutch basket to stop it turning while you loosen the nut. Bottom end rebuilds will take a lot longer, but they can also be done by anybody with a couple of days to spare. Click here to find all the parts you need for your rebuild. The Bottom End is Noisy - A worn clutch basket which has started to rattle, damaged or stuck bearings, a worn bushing and needle bearing between the clutch basket and primary shaft, or gears which are improperly lubricated may all contribute to bottom end noise. If you buy the tusk crank puller, you will find some great instructional videos online, and it comes with full instructions to help you out. This trick works well for me, and you can watch the video I found below to find out how it works. Flywheel puller (link to flywheel puller on Amazon), Plastic scraper (an old credit card will work), Large sockets and spanners, up to 28 mm should cover all dirt bikes. Carefully squeeze the piston ring into the ring groove, making sure the end gaps are in place over the pin, and lower the cylinder over the piston. As your hands brush against these parts, small bits of grit can fall into the engine, and wreak havoc when the engine is started. I have some mechanical skills and am wondering if this is a rebuild that I can do or if I need to take it to a shop. I am currently removing my engine to replace a leaky MAG seal. Get your 2020 MX girls calendar at Amazon by clicking here, Motocross arm pump: 10 steps to get rid of arm pump fast, Motocross Fitness: How to train for MX racing, Dirt bike riding tips for beginners: 11 top riding tips to develop skill fast, Dirt bike wheelie: Wheelie like a pro with these top tips, Dirt Bike Maintenance: 12 tips to keep your machine in tip top condition, 2-stroke top end and bottom end rebuild tips for beginners. Do this until the gap is correct, and be very careful not to file off too much of the ring. That being said, it took me like 3 months to build my engine, but it was my first time. If there is play, then the crank will need replacing, which means a full rebuild is needed. When it comes time to split the cases, you'll find that they are very tightly fused together, and you will most definitely need a case splitter to avoid damaging the cases. You can dispose of the metal head gasket and the base gasket, as these can only be used once. You can remove just one piston clip, and push the gudgeon pin from the opposite side. If you can't find the size you need, it's best to give them a call and they will tell you which piston the buy. The more oil that's removed the better, so leave the engine to fully drain for 30 minutes before proceeding. We'll also be removing the clutch assembly and the right side engine cover.Everything You Need To Rebuild Your Bottom End!https://www.rockymountainatvmc.com/Sales/482/Motorcycle-Bottom-End-Rebuild?utm_source=Youtuve\u0026utm_medium=Motorcyclebottomendrebuildpart1\u0026utm_content=Descriptionheader\u0026utm_campaign=YoutubevideosWatch Next: Motorcycle Bottom End Rebuild | Part 2: Crank \u0026 Bearingshttps://www.youtube.com/watch?v=vVKeT8Mh2dQMotorcycle Bottom End Rebuild | Part 3: Final Assemblyhttps://www.youtube.com/watch?v=ti_UkR3XjyECheck out https://www.rockymountainatvmc.com for all your parts, apparel, and accessories!Click Here To Subscribe To Our Channel!http://www.youtube.com/channel/UCQSXoYEPBXNPSx1hWbO2WRQ?sub_confirmation=1Follow Us On Social Media!FACEBOOK: https://www.facebook.com/rmatvmc?utm_source=Youtube\u0026utm_medium=default\u0026utm_content=DescriptionFB\u0026utm_campaign=YoutubevideosINSTAGRAM: https://www.instagram.com/rmatvmc/?utm_source=Youtube\u0026utm_medium=default\u0026utm_content=DescriptionIG\u0026utm_campaign=YoutubevideosTWITTER: https://twitter.com/RMatvmc?utm_source=Youtube\u0026utm_medium=default\u0026utm_content=DescriptionTW\u0026utm_campaign=Youtubevideos Simply put the bike in gear to lock the clutch and they'll come out easily. It won't affect the plating, but be very careful not to get it on any bare aluminium on the cylinder, as it eats up aluminium very quickly. Place the head on, and progressively tighten the bolts down to the correct torque in the order shown below. Everything from the clutch, to the cooling system, to bottom end components. A bottom end rebuild will obviously require engine removal, but many people leave the engine in while carrying out a top end rebuild. I use an EBC clutch holding tool, and I made my own flywheel holder by welding two pins onto a length of 1/2" square bar. I recommend removing this gear before the clutch, as there is a little trick you can use to loosen the nut, which requires help from the clutch. To remove the main nut that is holding the clutch basket, you will need to flatten out the locking tab washer. I guess some bearing in the bottom end went bad. Screwing them back in will also help you to remember where each bolt goes when you come to put the engine back in. When the flywheel is off, be sure to grab the small key from the shaft, and keep it safe by sticking it to the flywheel magnets. The next step is to remove the gudgeon pin, which is the pin that connects the piston to the connecting rod (con rod). Is it possible to replace the piston rings, rods and main bearings from the bottom end with only pulling the oil pan? At the same time, the gap mustn't be too big as this will cause blow-by, which will reduce compression. Simply place the gasket over the studs. A better way to remove old seals is to use a very small drill to make a hole in the seal, and then screw a self tapping screw into it. You can now use the claw hammer to pull on the screw, which will easily remove the seal. I use the Tusk crank puller (pictured below) and a Tusk case splitter, they work great and you can buy them as a package on Amazon as I did here > Tusk Tools. Look at the ring groove on opposite side to the arrow, and you will see a pin, this is where you'll place the end gap. The Tusk crank puller is essential for installing the new crank. It ran really great untill the engine seized. You can then remove the clutch plates and clutch basket. (pistons are numbered not color coded) When you rebuild the motor , your machinist will attempt .0001" accuracy and get real close, Something that was impossible in the factory (gang jobs). When it comes time for an engine rebuild, many riders pass their dirt bike over to their local repair shop to have the work done. With the teardown and machine shop episodes out of the way, we can now start rebuilding our block. This is done so that the rings join at the rear of the piston, to prevent them expanding and snagging on the exhaust port. This is done to shrink the bearings to make them fit into the heated (expanded) cases easier. I'm sure that led to some issues with the bottom end. If the ring is installed the wrong way up, it will feel tight, and it will stick in the piston's ring groove, so check that it moves freely before proceeding. Check out some awesome accessories for your dirt bike HERE. You will need the expertise of a mechanic to tell you if it is indeed time for an Hi Adam, you’ll need to take the transmission out. Many people will tell you that a cylinder must be honed before replacing the piston. Are there any things to watch out for with the transmission during this process such as components coming apart that are tricky to put back together? Cash Back Rewards Program. And we'll run through both top and bottom end rebuilds step by step, from start to finish to give you some valuable tips to help you along the way. 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