Honda CRF450R Bottom End Rebuild | Part 1: Disassembly

hey this is Charles with Rocky Mountain atv/mc today I'll be showing you how to split the crankcase on a CRF 450 are there are a few different reasons you could be splitting your crankcase whether it be shifting or transmission problems or if it's just time to service your crankshaft and bearings now keep in mind while we're doing this what problem you're trying to solve and that way you'll know what areas to pay special attention to to look for excessive wear this job can be pretty intimidating for a lot of riders but we'll show you it's really not that bad of job with the right tools and information now this video it's going to be a multiple part series so today we'll be focusing on splitting the crankcase and getting everything ready for inspection and we'll show you the tools you need and how to use them this engine came out of our 2005 CRF 450 R and this bike we're using for a Roadster racing series on our YouTube channel where we take a completely worn out bike we tear it down to the frame and we're going to go through every part and make everything nice and new and then we'll go race it so be sure to check that out and something I want to point out is this procedure will be similar from 2002 to 2008 so be sure to check your model specific service manual for more information proper procedures and specs now I want to take a minute to talk about staying organized and the reason we're showing you this at the beginning of the video is to help you figure out ways you can stay organized during the teardown process there's a few different ways you can do this you can take pictures some people will use bags and label the bags with what parts go where what I like to do is group everything together that came off as a unit for instance grouping all the clutch parts together and this type of thing will help you from getting overwhelmed later on in the reassembly process to do this job we'll need some common hand tools rags and safety glasses specifically we'll need some precision measuring instruments we've got a gear jammer and a penny and we'll show you how to use those later on we'll need a crankcase splitter and a crankcase installation tool we've also got a flywheel puller a flywheel holder some snap ring pliers and we'll be using a heat gun or torch and then we also have some contact cleaner and assembly Lube you'll also need a blindside bearing puller a bearing driver kit some wood blocks for parts we'll be using the wrench rabbet kit now this kit is nice because obviously we need to take our top end off to get to our bottom end and it comes with all the standard parts we need to do that including some of the commonly overlooked parts now if you do want to see us do the top end - we will have a how-to video on that at this point you should already have your top end off and if you haven't done that yet we have a great how-to video for that so check it out to start things off we'll remove all the parts on our clutch side of the engine and then we'll follow that by removing the flywheel and all the parts on that side and then we can split the case when removing the right engine cover you don't have to remove your clutch cover or water pump cover but you do have to remove these two bolts and this one and this one on the clutch cover we'll be replacing both gaskets so we'll take these covers off anyway with all of the bolts out we can now remove the right-side engine cover and to do that there's little tabs we can be really careful and lightly pry on those don't get too aggressive it with them and if you have to you can use a soft faced mallet to help kind of break free the gasket now we have this nice engine stand with a pan below to catch any of our oil but if you don't have this you can use some wooden blocks and you can use a bigger drip pan and just place everything on that when you pull the cover off be sure not to lose the three dowel pins that are on here and keep track of them the next thing we need to do is remove our clutch so to start that process we'll remove these ten millimeter head bolts in a crisscross pattern and that just makes sure we won't warp or damage anything to help us loosen up these bolts we'll be using a motion pro gear jammer and if you don't have this tool you can also use a penny since it's a soft surface and we can jam it between our primary drive gears to help get this pressure plate off I just pulled on our clutch release lever and it pushed it right out now we have a thrust bearing right here and our lifter assembly so be sure to keep track we've got this bearing on the end the washer and this push rod that goes all the way through now we'll remove our clutch plates and when we do this we can take each one off you can measure the thickness and keep them in order because a lot of times the first plate and the last plate will be a little different and sometimes you have some gutter springs in the back so be sure to keep everything in order as you take them off and another thing you want to check these steel plates check for any bluing or warpage so these grooves that you see should not be here and these are actually caused from the friction plates now this surface right here it should be a smooth machined surface so the plates can ride back and forth on it easily our inner hub right here actually doesn't look that bad it's actually pretty smooth it does have some light marks but not enough to really make a difference so we'll probably just be worrying about this basket and I think our hubs going to be okay so we have a lock washer behind our clutch hub nut we'll need to bend back both tabs that are bent down on to it in order to remove this nut so we'll go ahead and do that and then we'll show you how to use our clutch holding tool to loosen this up now we'll take our clutch holding tool and we'll adjust this up so when we tighten this we just want it to want it to be snug but we want to do it as light as possible because this is aluminum we don't want to damage any of these fingers so only do what's necessary just to keep it snug then on ours we've got a twenty seven millimeter nut I'm going to use our breaker bar and we'll loosen that up and keep in mind behind that note we've got the washer and this lock washer this washer always needs to be replaced now we'll remove our hub and when we do this keep in mind you know usually be washers that are stuck on to this so if you don't pay attention to that and they're moving it around it's really easy to lose that kind of thing before we take our clutch basket out this has this is part of our primary drive system so we need to loosen this nut and this bolt and before we do that you need to pay attention to the timing on these and if you do have more questions on this you can look at your service manual but what it is you've got three dots on there and they should line up all at the same time so we've got these three dots all in line that's how you know it's timed right and this is we're timing our counter balancer shaft is what we're doing so just with that being said we'll go ahead and put our gear jammer in here and we'll loosen these up we'll go ahead and use our motion Pro gear jammer now on our primary drive to loosen this bolt and nut up now we'll take our motion Pro gear jammer and lock up our counter balancer gear and we'll use our motion Pro twenty millimeter spanner socket to loosen the special nut take care to not lose the washer now we'll remove our gear jammer we'll take our clutch hub off and keep track of our needle bearings that are in there there should also be a spacer and then we'll remove our primary drive gears and counterbalance our weight and counterbalance our gear now we'll remove our idler gear that works with our kick start and primary drive be sure to take off the collar as well with what we're doing there's no need for us to remove this kickstart gear but we'll show you how to do it anyway and all you do you will remove this spring and you'll pull out on this shaft making sure our shift lever is removed we'll pull out this shift shaft here's a washer that you want to keep in mind not to lose next we'll remove our shifting mechanism from the shift drum cam to do that we'll remove these two ten millimeter head bolts and try to keep it as an assembly as best as possible these pieces here are spring-loaded so take care to keep everything in place for now and we'll show you how to inspect everything later on next we'll remove our shift drum cam and this stopper arm we actually will not be removing it the only inspection here we really need to make is to make sure the spring is still in good condition and as you can see our Springs back good so we're okay there to help us do this we'll move the shift arm out of the way with a screwdriver you'll notice the shift drum cam has a detent right here and there's a pin in our drum so just be aware of that when you go back to assemble it also this mounting bolt will need to be re locked tided the last thing we'll need to do to prep this side will remove these bearing retainer bolts just since it's easier while we have the engine in the stand rather than on the bench with our clutch side taken apart and prep will now move to the other side of the engine and begin with removing the flywheel cover the first thing we need to do to remove our flywheel cover is take out our oil filter this filter is pretty dark and there is some junk down in the bottom of this paper another important thing you can see somebody's pried this cover off in the past and something you never want to do is stick a screwdriver between covers that have sealing surfaces luckily this one seals with an o-ring right here but if we were to pry the cover off where the gasket normally goes you could damage this cover or your case and you don't want to do that you'll notice we already had two of the bolts on top out and that's because they were holding our clutch cable bracket on so we remove those when we remove the engine from the bike to get this cover off even after we get it loose it might be a little difficult to remove because we're dealing with magnetism and it will want to suck back on so what we'll do we'll pry it off a little bit and then once everything's loose all the way around we'll try to pull it off as straight as possible to remove the flywheel nut will use the Tusk flywheel holding tool then we can hold that in place and loosen this nut to use this tool you'll just adjust it to the correct size and then tighten it down onto the flywheel with our flywheel nut removed we can now pull the flywheel using our Tusk flywheel puller and we'll do that by threading this piece on to the end of the crankshaft and what that does is protect the crankshaft and will screw the main part on to the flywheel now we'll use our wrench to hold the body of the puller and then tighten the bolt down and that's going to pop our flywheel off after that we'll remove our counterbalance our shaft will check for smoothness in our oil pump by turning this plastic gear now we'll remove this snap ring next we'll remove our cam chain guide be careful not to lose the washer that sits just behind it next we'll remove these two brackets and then remove our oil pump strainer assembly now we can remove our cam chain and we'll remove all the mounting bolts on the left side of the engine now we'll remove our Woodruff key just so we don't lose it as you can see our Woodruff key is damaged and this surface should be completely flat so we will be replacing that now we'll move the bolts from our left crank case half and something I want to point out is there are three bolts with copper washers on them one here one here and one on the bottom they're also marked with arrows where they go so when we put it back together we'll want to put new copper washers on nuts so since we have these three bolts with the copper washers we're gonna keep track of and we've got a couple brackets these are pretty hard to put in the wrong spots but still we thought it would be easier to use a cardboard cutout and we'll draw this side of the engine case and we'll mark where each bolt goes and we'll actually stick each bolt through the cardboard in our drawing and that will make sure we get everything back exactly where it goes you'll loosen them a little bit at a time in a crisscross pattern and that way you avoid warping or damaging the case this may seem a little over the top but this will make assembly much easier and these bolts a few of them are different lengths so it'll just save you time from having to try different bolts and different holes and trying to get them in the right spot now we have this done but always check do one more check make sure you didn't leave any bolts in and now we're ready to take our Kate other case half off be sure to check for any washers that might have stuck to the bearings because of the oil the reason we pulled the right crankcase half first is we need to remove this one-way valve and we also need to remove the oil pump so keep in mind this oil pump is three pieces and we'll try to keep all of that in order so this del pin that was rusted in here we do need to install this right crankcase half and I don't want to reinstall it with the del pin in the condition that it was in so we'll remove it now and since it was so stuck we'll actually have to use some pliers to remove it and just to make sure it doesn't collapse you'll need something that's about the same inside diameter as that and then we can squeeze on it and it just keeps the del pin from collapsing all the way and since this one's so bad we'll be replacing it now we'll reinstall our right crankcase half with that installed we can now flip the crankcase over so the left side is facing up now we'll remove the left crankcase hack again take any washers that are left in this case half and put them back on their shaft now we'll remove the crankshaft next we'll remove the dowel pins for our shift Forks and we'll remove our shift drum remove your shift Forks and now we can remove the transmission shafts as an assembly and keep in mind that we do have the other washers on the other side make sure none of the gears come off of the transmission shafts while you're moving them from the crank case half keeping them on we'll make sure they're in the correct order if they do come off you'll want to reference your service manual to reinstall them and that's all there is to disassembling your bottom in this is the first video in a three-part series the next video will cover cleaning and inspecting your parts and what things you might need to replace and the third video will cover reassembly if you need any parts for your bike or special tools we have a lot of different options on our website so be sure to check that out and if you like videos like this and want to see more like it check out our YouTube channel and subscribe I'm Charles thanks for watching

Channel: Rocky Mountain ATV MC

Views: 113,379

Keywords: Rocky Mountain ATV/MC, rmatv, rmatvmc, atv/mc, atvmc, motocross, rockymountainatv, dirt bike, motorcycle, off road, offroad, honda crf450r top end rebuild, honda crf450r engine rebuild, honda crf450r bottom end rebuild, 2008 honda crf450r engine rebuild, wrench rabbit engine rebuild kit, honda crf450 bottom end rebuild, honda dirt bike rebuild, splitting cases crf450r, how to rebuild a crf450r engine, motorsport products mx engine stand, 4 stroke engine rebuild

Id: j-mMMKKMuyw

Length: 20min 49sec (1249 seconds)

Published: Tue Jan 21 2020