October 10, 2019 HomeArticlesBuilding My CR250 Engine! Building My CR250 Engine! By Maxine Hayes Articles, Blog 65 Comments Tags:2 Stroke, 2 Stroke Engine, 2 Stroke Engine Build, 2 Stroke Motor, 2 Stroke Project, 2 Stroke Top End, 2003 CR250, 250 2 Stroke, and, Building My CR250 Engine, Cameron Niemela, CR250, CR250 Engine, CR250 Motor, CR250 Project, CR250 Rebuild, Dirt Bike, Dirt Bike Build, Dirt Bike Project, Dirt Bike Repair, Engine Build, Fixing CR250, Fixing Motorcycle, Honda, Honda CR250, How to, Motocross, Motor Build, Motorcycle, Motorcycle Repair, Niemela, Rebuild, that, the, Top End Rebuild, Two Stroke Related Posts OBS v21 Update – Scripting, Audio Overhaul, Multiview + More! Cruise Power Cube Review Trond Multi Plug Travel Outlet with USB Before You Start a YouTube Channel Watch This… About Author admin 65 Comments Fulvio Vallelonga 👏👏👏💪💪💪💪 you are amazing!!!! Hello from italy. November 4, 2018 Reply Jupiter Rising Should push the rings down into the bore with the piston to get the rings even then measure the gap. Not the way you did it. November 4, 2018 Reply KyleMatt11 What kind of cancer does a young dude like u get? November 7, 2018 Reply Bill Kinsey just seen your channel. u my frend are awesome lovely builds and kick cancers ass 🏍🏍🖒 November 9, 2018 Reply Paul Djerassi Cam use the piston to push down the ring its best that way crown first . November 17, 2018 Reply boodee offc November 2018 !? November 17, 2018 Reply powerrangjer2001 sir… you torque tool 13:00 can u give me u small nm n max nm how max higher… November 20, 2018 Reply LusoCMD Keep strong Cameron!! November 20, 2018 Reply Jon Jones Is that cylinder painted or just polished? December 9, 2018 Reply kiltit Sorry I missed the raffle. Awesome videos. Good luck with the treatments. December 13, 2018 Reply biker killa Nice job broo i try to rebuild my ktm 125 86 . .and after to wacth this i think is posible December 14, 2018 Reply Diri Yunani you are the vlog I ever seen man!!! you are the man completly detail and clean job!! very very totally suberp!!! you are true mechanic!! December 23, 2018 Reply Global Roots Thanx man ! I learn so much from you man..Kick that cancers ass man 😎✊ December 24, 2018 Reply MrCalifornia1234 Well done! 👍 December 25, 2018 Reply spondonzeex10r Just seen your videos tonight – great videos, skills and builds. I'm still a bit behind, but I'm hoping you are recovering well. All the best from a fellow (road) biker 👍 January 7, 2019 Reply Tony Turi 12:57 January 9, 2019 Reply SumoPwn I saw all of ur rebuilding series, just gorgeous! I’m gonna buy myself a YZ 250 and I’m looking forward to do a little rebuild story too 🙂 Just keep on fighting against the fucking cancer mate!!! Greetings from Germany ❤️ January 13, 2019 Reply Jamie Murphy Great vids cam just rebuilt my first complete engine with your magnificent help keep them coming January 13, 2019 Reply David Tyra Send me your info I’ll help you with your cost January 16, 2019 Reply Rider Klaver When inspecting ring gap, just push the ring in with the top of the piston, that way it is in 100% level January 26, 2019 Reply rod dave way to go brother, kik cancors ass February 12, 2019 Reply Bill Clinton Did you really need to do all that measuring on the rings because you widen them up and they went on the outside of the piston ?? I'm confused bro February 23, 2019 Reply Joey Tonnesen Chemo will kill you try 35% food grade hydrogen peroxide, do the one minute cure protocol. February 24, 2019 Reply Gabe Bowden Can’t go wrong with stock pistons. February 27, 2019 Reply Amber Bristol Would you take apart the crankcase and put it back together kinda in steps i guess. We just got an 88 honda nx250 and there is a problem inside the crankcase with one of the gears and we are not sure about taking it apart because were new to dirt bikes March 2, 2019 Reply Chad Waters Great vids. One thing I noticed, you mentioned that when you install the circlips into the pistons, you prefer to line up the circlip gaps with the gap on the piston. Most manufacturers have a tolerance and diagram displaying a minimum distance that the circlip gap should be from the gap on the piston. For instance, my Yamaha indicates a distance of atleast 3mm for my 2017 YZ250F. Its good preference to keep the circlip gap as far away from the gap on the piston. March 7, 2019 Reply Moto Mirius Late to the party but you might find it easier to put the piston with rings into the cylinder and then put the locate the piston onto the connecting rod. Loving the videos – so much to learn. Skäl David March 12, 2019 Reply Cool Kids co. 9:28 something broke March 12, 2019 Reply Martin Benoit Gloves when touching a piston. March 18, 2019 Reply Vicen Benito camela me gustan todos sus videos se nota que usted es mecanico i piloto de primera osea categoria suprema March 25, 2019 Reply Dustin Black You can use the piston to push the rings in square to the bore for your end gap. April 19, 2019 Reply donald trump god bless you May 9, 2019 Reply AUSSIE NINJA23 Dude fucken keep kicking ass love your work dude May 12, 2019 Reply Steve A You should have sent the piston with the cylinder when the cylinder was repaired so the repairer could set the piston to cylinder clearance more accurately. An easy and accurate way to square the ring in the bore is to use the piston to push the ring to the point you want to use for making the measurement – it should be checked near the top, a little above the ports and just below the ports and see if it has less gap at one point than another – set the gap for the tightest point. Assembly lube on the rings is not recommended. Too much oil in the ring land may carbonize when the engine is started and stick the ring in the groove – just wipe the ring with two stroke oil. Anti-seize is not recommended to be used on the cylinder studs – it will cause over torquing – a light coat of two stroke oil is adequate (dip the stud in oil and let stand vertical on a paper towel overnight). Holes in the front of the piston has nothing to do with being forged or cast – the holes are in the piston to provide lubrication on the exhaust bridge so the rings will last longer – I drill holes in all two stroke pistons that run in an engine with a bridged exhaust port whether they are forged or cast. Vertex does not drill the piston because it is an extra operation and increases the cost of the piston. Wiseco drills their piston because it is a high performance piston and it is reflected in the price. I STRONGLY DISAGREE WITH THE MASSIVE AMOUNT OF LUBE ON THE PISTON AND BORE – ONE DROP OF TWO STROKE OIL SMEARED AROUND THE LOWER 1/3 OF THE CYLINDER BORE IS ADEQUATE! One thing you failed to mention or do was to put two stroke oil on the bottom end of the rod and to put a few drops of two stroke oil in the feed holes for the main bearings in the transfer port base (one on each side) in the crankcase. You didn't detail the torquing of the cylinder base nut under the power valve operator – looked like you just tightened it with a box end wrench – how did you verify the torque on that nut? May 15, 2019 Reply Lucas Hoover A lot easier to install the piston into the cylinder on the bench, then lower down onto the rod. Much less chance of damaging the bore too. I dig your videos keep it up! May 16, 2019 Reply The Usual Suspect put the gap of the wrist pin cir clips 180 away from the gap in the piston May 27, 2019 Reply Jon S Any good ways of making a 00 cr250 more powerful? May 30, 2019 Reply robert foresman OUTSTANDING !!! June 1, 2019 Reply shaun bathgate Awesome assembly, i really enjoy your videos man. Very well put together June 12, 2019 Reply Ryan Ritchings So hooked to your vids June 12, 2019 Reply Dragon800 this is just amazing we have all been waiting a long time to see this congrats man! An easy way to do ring end gap is to bring the piston up from beneath and push the ring until its level. And its good to use some assembly lube. June 20, 2019 Reply Chris Thompson Watched every vid Love em! you stay strong kid want more of these vids Regards from the UK June 23, 2019 Reply Alisa Alisovna Спасибо👍 June 25, 2019 Reply Domino Why not use a pencil or something made of wood to get those circlips in the piston? June 26, 2019 Reply Eric Hildreth Great video and your motor looks sweet!! One thing to suggest, invest in the motion pro cylinder wrench, one size is 12mm and the other is 14mm and they give you the conversion chart for the torque wrench (3/8" drive)…use this when you tighten the cylinder stud nuts use this on all four, that way they are all even. Trust me I have one and it's worth every penny! Kick cancers ass and keep up the good work!!! 🙂 July 7, 2019 Reply Lee Chandler September 2018 I was diagnosed with stage 3 pancreatic cancer I went through 12 chemotherapy treatments and surgery to remove the tail end of my Pancras where the mass was they also removed my spleen but I became allergic to the chemo so here's a shout out from "Hard 2 Munch Live Action Cell Floor Productions along with Love Bound Film's" July 15, 2019 Reply Jacob Tsimiklis My dude loves his lube July 17, 2019 Reply Alex Postma nice vid. i love working on 2stroke engines.i have some 2stroke bikes here and Always busy with them or riding them. i work as a paramedic, wich can be a stressfull job from time to time, so working on these bikes is a nice hobby to let off some steam from time to time.wish you all the best man! July 18, 2019 Reply Jim Madonna Cameron power seal did my cylinder. They do great work. July 21, 2019 Reply 50337andy Just watched all your videos on this engine build up to this point but it's late here in the UK so I'm headed to bed now.Brilliant presentation by the way and fascinating to watch. 👍👍👏 August 1, 2019 Reply Dwi Rahmat Subtitle for indonesia? August 3, 2019 Reply Francesco Porpiglia Use the piston itself to fix the piston rings into the cylinder at the correct height for measuring the tolerance correctly. And the rings must be pushed a bit ( 1 cm from the cylinder top) when you make the measurement bc next to the upper side, the cylinder is not reached by the rings when the engine is working and it will have kinda brand new dimensions, so push rings into the working spots to have a correct measurement. For the rest really nice video! Very well done and nice assembly! August 4, 2019 Reply RevAldea I know this is a rather bit later but there is an easier way to install piston ring into the cylinder and is as follows. Hold the piston ring with the gap outwards from the cylinder while slipping the ring into the cylinder then rotate the ring towards you while in the cylinder until it has completely seated in the cylinder then use the piston to square up the ring from below now, measure the ring end gap if it is tolerances then rotate the back out the same way it had been done to remove the ring and the install this ring on to the piston's bottom ring grove. Do the same with the other ring but instead install this second ring in the piston's top ring grove. You may use an old piston, instead of the new piston if you have already installed this new piston on to the small end of the connecting rod, to square up these piston rings only after it has been well cleaned. This method has been learned for and as a time saving, the reason is during pit operations while getting ready to get back into the race with your bike, where time expenses count greatly during long races where you are allowed to make quick repairs on your bikes. Not I'm talking about jetting operations, this for those times the bike had breath some dirty air and caused poor running afterward after all is said and done, racing is an outdoor sport and it is where the dirt is, and all have fallen at some time or another. Ten years of various motorcycle racing and as a pit crew member too. August 4, 2019 Reply RevAldea I 'm not giving any bad-mouthing about his work, In fact, he is doing so well at all the various functions about the rebuild and these are so very close to doing right and fast as you would need to do in the pit area would and could only add what I had added is all that could the difference of winning that all-important RACE DAY!!!I really respect this dude and I'll be praying for him and if I can find his EMAIL address I'll tell him about own bout with the "C" and something to help him get into better shape too. follow his directions plus add the tip about ring alignment I had added you will need practice you will get faster at doing this operation. Everone love and most importantly have fun Life is to short not to. Hey, dude get yourself some selenium about 60 mg tabs and take them three times a day. Of course, check with your doctor about taking selenium before you do them. They helped me to recover faster those "Big C" stuff really knock me down to my knees every time and if your state that will legally let you use medical hemp ask for it, from your doctor that helps too. August 4, 2019 Reply Dan Gleeballs Beautifully built motor! !!! August 7, 2019 Reply Specbolt Fasteners Nice build video! Specbolt would love to sponsor your next project. #specbolt Have you seen our Nickel Wurks bolts yet? August 7, 2019 Reply victor zagornean Damn dude you can definitely kick cancers ass 👊🤘Were with you bro (keep up the good content) August 17, 2019 Reply Tazer1998 Should do some videos of you riding your bikes August 26, 2019 Reply Bruno S Goooooood job "Bravo"!!!Stay in shape buddy, from Portugal September 2, 2019 Reply David Scott Jr I wonder if they have one of those heads for a CRF50 September 2, 2019 Reply msw5293 Kick cancer's ass man got you in my prayers🤘🏻 September 19, 2019 Reply MrStoneycool69 I did something very similar to my KX250 20 years ago, I didn't ride it too much before I sold it. September 24, 2019 Reply Tony Paterson Great build series. Subscribed. September 30, 2019 Reply Kev Z Use the piston to square up the rings in the bore before measuring ring gap. October 3, 2019 Reply your name how much does a piston to a cr250 cost? im noob xD October 10, 2019 Reply Add a Comment Cancel reply Your email address will not be published. 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