How to rebuild 2 stroke engine - Yamaha YZ250

hey jay here we're on the next part of our yz250 build this is a build our steel frame yz250 that we thought was a 99 but our guy messed up and it's actually an o1 we've had that problem happen a few times even rattle's done that with us give us the wrong year and then things are different it's it happens right right oh it does unfortunately it happens to me too often and it's not my fault it's always guys tell me something so always check the frame numbers good good uh lesson okay so we got our yz250 engine here all apart and brad pair pro's long time friend friend is going to rebuild this engine for us right now we've got the engine all vapor blasted that's why it looks so nice so it's all vapor blasted when you vapor blast an engine you need to split it all apart you're going to get stuff in there you can see we got worn clutch plates crank crank is very old and worn so needs a new crank piston and main bearings same time so it was time for a rebuild perfect time and luckily the cylinder is still in good shape so brad's going to assemble this entire engine he's going to clean the power ball at the same time and put this whole thing together with new clutch plates and so forth we'll report back to you okay so the fun part of this story is when i showed up here he already had the in he didn't want to show it because it was going to take it takes a while and he was just trying to save some work and make this a shorter day no such luck colorado no no no we're going to do it right so here we go brad show us what to do so this one has like nowhere their pads are really good this one has a little bit you can see teeny bit of wear but that's i mean it's so minor and you you actually if you feel a step that's when you're morphing yeah and then if they're these don't have it but if right here will be a groove if you get a groove in there right the shift works done because it's bent and it's pushing on the gear so if you get you can kind of see that little mark right there when they're bad you'll see it it's a gnarly gnarly little uh groove gone too many days in the darkness without a glimpse of the light [Music] [Music] [Music] [Music] [Music] okay got the transmission in there a little bit of a pain the way it goes in um you just gotta line it up and i keep the shift forks to the side put the drum in the middle and then slide it together and drop it in uh sometimes you gotta do a little wiggling and get it in but once then it's fine show us how we you know it's working right right now i know you're good like chipped in there yeah yeah working good it's not in right those times you're having a problem what do you see is it locking up yeah if you can't shift it if it's just stuck and like one of the gears is on wrong it won't move it won't go into its spot so you wouldn't be able to shift at all so perfect so now we're going to put the main bearings in so i heat the cases up and the bearings are in the refrigerator getting cold and then they'll pop right in this will take a minute though you know just like that [Applause] turn it off easy peasy all right now we're going to silicone the cases we use yammerbomb4 i put a good amount all the way around don't get crazy and put a ton of it because then it's just going to dry and end up all and everywhere else in the gasket kits there's an o-ring that goes right here for the the coolant canal um i always make sure there's a little bit of silicone in there before that way it holds the sucker in there just like so and then next what we're going to do is i'm actually going to preheat a slug on the main bearing get the slug really hot so the inner race of the main bearing is hot and we'll drop the crank in so the reason why i heat up the slug on there is i don't want to put direct heat right on that main bearing so we do heat transfer with the slug uh works really really good and then ratto's gonna hand me the crank out refrigerator yep just like that see how it just fell in there's no tapping no beating no nothing it's in that's good [Music] we are born again [Music] just like a scene in a garden you will grow to be tall so the reason why i like doing the seals after the fact is sometimes when you put the seals in the crank catches it and can jack the seal up or push it back out and it could mess it up i'd rather just put them on after effect but either way is good here we're going to change the clutch arm seal so you want to pull the little safety pin out [Music] [Music] [Applause] [Music] [Applause] and then put this back in now be careful when tightening this down the threads are really thin on this thing just barely snug that sucker in we're gonna start on the right side of the motor and first what i'm gonna do is install the right main seal and if you know it all right so now we're going to put the drift indicator drum in has a little slot and inside of here is a little pin so you want to make sure that that gets on correctly and then i always put a little bit of loctite on the bolt not a lot and i use blue so it's not that tight [Applause] [Music] [Music] we are born again [Music] your head [Music] in this build we're using spec bolts comes in the whole motor kit which these bolts are amazing they work really well i use them on all my projects jay use them all we didn't have these when we this morning putting this together so they just got here so i did them one by one took one out put one in now we're gonna start assembling the right engine side and we're good to go too many days in the darkness without a glimpse of the light running tired and broken and scared but i swear i'll never give up the fire i see you broken and [Music] [Music] [Music] with again [Music] so we soaked the hinson clutch fibers um let them soak for a while get all nice and lubed up now it can make a mess as you go to install [Music] just like a seat in a garden you lift me up in your presence we can watch the sunrise just a couple of bruised upper toes that believe that it was worth one more try with we are born again [Music] again [Music] hey kid don't ever let them get inside your head they'll tell you what to do in life instead of everything you know that you can get don't let them guide your life towards regret i'll fight for what i love with every breath my past is filled with things i won't forget i use them all to push me to my best so treat the worst of times just like a test if only i could go back in time i doubt myself that everything will end up all right just push yourself test yourself figure out what you like and find your limits don't be rigid always work towards a prime surround yourself with open minds people can't change your life a few friends with intent can help you feel alive find a passion take some action and with a little time just be patient make a statement try to enjoy your life they'll try to kick you while you're down they want to rise up while you drown and when they finally think you're wounded that is your chance to be ruthless be [Music] and they're scared i walk a straight path not many can say that i'd like to play fast cross me and there's payback you better pray that i don't see your face at any place that i go i know you hate that i've been doing fine i'm not wasting any more time i live for the fight and the guy and i think that the pain that's deep inside is what defies so i won't give up i'm gonna make it to the top i don't care what's in my way i swear i'm never gonna stop i could fall flat on my face and i swear i will get back up cause i don't deserve a thing and the road ahead is dark [Music] they'll try to kick you while you're down they want to rise up while you drown they want to fill your head with doubt they're silently scared that you'll figure it out i'll make it look like ruthless [Music] uh [Music] [Music] [Music] ruthless [Music] [Music] i don't mind climbing eight more floors cause these stairs [Music] [Music] [Music] please remember enjoy the show let's get happy before we get older we don't need plans or a fancy agenda well let's just see where it goes we got no care for the way people stare at [Music] if we keep on [Music] one more dance for the doors get closed please remember enjoy the show let's get happy before we get old and go put on that old wedding dress now probably still fits like a glove and tell the band to play one more slow song cause you still have all my love [Music] please remember [Music] okay so that's a wrap on this yz250 engine build brad did an amazing job as always um a lot of good parts in this thing right yes sir and we have little segments on doing the hinson clutch um putting the power valve together separate video where you get some tips on that so we have some really good pieces here again the engine was vapor blasted by sano metal finishing spec bolts all around the whole engine got our hot rods crankshaft vertex piston d-force re-cage henson clutch and it all comes out amazing we're gonna have a new super sprocket on here we got our hot rods makes the whole rebuild here all that stuff's been done i'm gonna get a new cover for this i'm working on that with lightspeed so that it looks just just right so really fun build brad did a great job rattle did an amazing job behind the camera and editing this video as well right rydel yeah you bet all right so hopefully you enjoyed this wise you 250 engine build watch this and then shortly you can be able to see the other finish complete build on this bike here real soon

Channel: Dirt Bike TV

Views: 75,752

Keywords: yz250, yamaha

Id: haMEKbGHbW0

Length: 20min 26sec (1226 seconds)

Published: Sat Apr 30 2022