02 cr250...Ready to build engine, just a few questions....

Ok, I have a few threads on here from questions on crank bearing play, to using a new 07 crank in an 02. Got that all figured out, and parts are on the way. I have a few questions and I would appreciate any help I can get with them.

Whats the best way to completely clean the case halves, after all bearings removed? Tub of kerosene be ok?

Whats the best method on cleaning the gasket surfaces on the halves? You can see where the last gasket had printing on it, and it left a film on the halves. Dont want to use anything that will scratch the surfaces ( If they arent already from the last owner, but they seems good as of now )

After cleaning the halves with whatever you suggest, should a quick shot of break cleaner be sprayed as a final touch?

The bolts that hold the retainers for the bearings in each half ( One side is 8mm head, and the other uses phillips heads ), Should I need heat to remove them? I assume there is threadlocker on them as the manual calls to use it when installing new bearings. Hate to pull the threads.

Another question on the threadlocker during reassembly, It says medium honda brand which is orange. If I recall, the permatex brand medium is blue, is that ok? I heard stories of the permatex brand red pulling threads in aluminum for people when they ever need to tear it down.

Lastly ( I hope ), I had the bearings for the shift drum pulled out. The real thin one with all the needle bearings.....I didnt notice before pulling it, but one side of that bearing has more of a "lip" on it. I didnt take note before pulling it, and I am not certain which way I should install the new one. I been looking at pics, manuals, etc....Nothing can been seen well enough to tell me.

Sorry fella's for all the questions, and being a nag. Really. Just want to do this right the first time, so I can be worry free for a long time. Any help is greatly appreciated.

For the gaskets Just give em a little scrub with some wd40 or you could use spray on gasket remover for caked on ones. Never use red locktight on aluminum. Blue is fine. The only place I ever use red is on the clutch nut. I'm interested in other responses as well for cleaning. Typically I just get a bucket of water and go to town with degreaser and scotchbright pads. Then brake cleaner before assembly.

Take some pics and post up as you go!

Well, wish I could update this with better results thus far. Got all my bearings ( crank installer, case splitter, torque wrench adapter, clutch holding tool, etc ), except service honda sent me one of the wrong ones. Wish that was the worst of it, but it's not. Done lots of reading and videos preparing to install the bearings. I decided to try the oven trick. I read where people put the case halves in for 20-25 mins at 200 degrees. I put my oven on 225 and left them in for 28 mins. Pulled the nice frosty covered bearings from the freezer and dropped it in the right half. It went in about 1/8 inch and stopped. Cooled so fast I tried to pound it in with a small socket. I didnt have one the diameter of the outer race, so I took it to a friends house where he had huge sockets. Went ahead and drove it on in, and done the other side. Well, the side I beat on, feels like $hit. I think I ruined it. I am gonna need to redo it. After thinking more, I might just replace them both without hitting them in. I also noticed the bearing I replaced right behind the clutch arm ( the one with one side sealed ) dont want to turn real easily. Dont know why. Have any ideas? Anyways, what are some opinions on redoing the mains? Have any tricks? What can I do next time to do it right? Put them in at a higher temp? Torch? I see vids of people using torches, but many say not to. By now, the wife has had it with me and my bikes. She's beyond pissed. I been telling her "this is it, all I need ".

Edited by wykyd450r

Accept the fact that your wife will never approve. Whatever. C'est la Vie.

Guy I took my bottom end to used a pneumatic driven grinder with a soft scotch brite pad-like attachment (round) and cleaned up the matching case halves. Also used mineral spirits in a sprayer attached to an air hose. First blasted the metal and then a plain old wire toothbrush to clean up all the dirt. Of course did all of that prior to installing anything new. On my second top end (that I did recently) I used "industrial" strength scotch brite pad on the outside of cylinder with Bel Ray grease/dirt remover (spray can) and it looked almost as good as new.

Well, ordered new main bearings and one for the left mainshaft. Decided to take the easier rote and let the local honda powerhouse install them. Service mgr walks out and said bearings are in, except he messed up the mainshaft bearing ( one side sealed, that sits where the clutch arm is behind it ). Kind of pised me off, so I told him I have a new one in the truck that I just put in, but took out as it was harder to turn than the original one. He put it in, and said it was ok, with the resistance it has. It turns, but is just "stiff". Anyways, I leave and go home. I notice most of the bearings I had in were dirty. By now, I am super pissed, because they either threw it in the parking lots of seen hom much dirt their tools can collect. So I went ahead and put kerosene in a clean tub, and used a syringe thing to spray onto them to clean them out by pushing on it as hard as I coild to "blast" dirt/metal out. I got quite a bit of stuff out of them. They all sound good now, for the most part. ( actually the mains werent too bad ). The one mainshaft bearing I had previously replaced and taken out, is still pretty stiff. So anyone have an opinion on what I should do with that one bearing? I believe all of the others are good to go. Should I trust the guy at the dealership and believe that beaing will be fine? It has no play or anything, just harder to turn. Just want to get this thing done. Its been enough worry/headache. Sure hope the worst is behind me. If its good to go, I plan to do the bottom end today, hopefully get it buttoned up.

Lesson learnt on shops. Firt time ever going to them for repair work, and the last. I should have just done the last few myself. All new bearings, I should be happy.

Edited by wykyd450r

I can not agree with you more. Those bastards at the shops look down on you and can not be trusted for the most part. SUre some are good. OHH doing it your self your not trained! Ya can train an ape, but your can't teach pride and craftsmaship.. Thats the difference between us and them. Don't overthink it. A bearing and seal driver would have been useful or an old bearing to match up. A heat gun is very useful (not a hot as a torch) Aliminum expands more than steel so its not really a race against them reaching the same temp for many things. Also I find that heat sometimes takes 5 mins or more to "set in" and have the whole part expand. Get the Honda general service manual for free. I think you lost the heat in the case when you drove over to your buddies LOL. Still good on you for tackling this.

I phoned up a shop to get valve clearances (new bike being cautious) Ya shop, not parts. Says intake 15 mm exhaust 5 mm. This was the shop!! I said is the decimal right. He said oh 1.5mm .5mm. I new he was wrong! Sorry dude 0.05 mm and 0.15 mm. I checked. Same as all the other bikes I had over the years. All my feeler gauges in these sizes are bent!!! Standard stuff!

Bearings all cleaned up, and taped over with duct tape to keep anything out while I pull the crank in, sometime today hopefully. Still not 100% satisfied having to use that "tight" bearing for the mainshaft. It's smooth, and new atleast. That makes me feel not so bad. Gonna go out here and make sure my washers on the tranny shafts are facing the correct way. Maybe the ones on the ends might have gotten switched when I was removing and they stuck to the cases, or when I was practicing the tranny while waiting for parts to come. Ofcourse, I will make sure they are clean before installing. Probably put em in as a whole in a pan of kerosene and brush them. Then hit em with brake cleaner. Hope all goes well from here on out.

Edited by wykyd450r

Well, wish I could update this with better results thus far. Got all my bearings ( crank installer, case splitter, torque wrench adapter, clutch holding tool, etc ), except service honda sent me one of the wrong ones. Wish that was the worst of it, but it's not. Done lots of reading and videos preparing to install the bearings. I decided to try the oven trick. I read where people put the case halves in for 20-25 mins at 200 degrees. I put my oven on 225 and left them in for 28 mins. Pulled the nice frosty covered bearings from the freezer and dropped it in the right half. It went in about 1/8 inch and stopped. Cooled so fast I tried to pound it in with a small socket. I didnt have one the diameter of the outer race, so I took it to a friends house where he had huge sockets. Went ahead and drove it on in, and done the other side. Well, the side I beat on, feels like $hit. I think I ruined it. I am gonna need to redo it. After thinking more, I might just replace them both without hitting them in. I also noticed the bearing I replaced right behind the clutch arm ( the one with one side sealed ) dont want to turn real easily. Dont know why. Have any ideas? Anyways, what are some opinions on redoing the mains? Have any tricks? What can I do next time to do it right? Put them in at a higher temp? Torch? I see vids of people using torches, but many say not to. By now, the wife has had it with me and my bikes. She's beyond pissed. I been telling her "this is it, all I need ".

Next time you try to install the main bearings you should use a blow torch instead of the oven. Put the bearings in the freezer like you did (the longer the better). Now heat the case half right around the race where the bearing goes. Keep the torch moving constantly when you are doing this. You want it to heat evenly and completely. Have a slightly wet paper power handy and when you think it is hot enough squeeze a couple drops of water out of the paper towel onto the case half. Make sure you don't do to much as it could crack the case. A few drops won't do anything. The water should sizzle and dance around on the aluminum. If it does not then keep heating. Once at the correct temperature take your bearing out of the freezer and drop it in. For me if you do it straight they usually drop in 2/3 of the way and then I finish it off with a large socket.

Well, not much progress to report, other than getting the tranny parts cleaned up, and put together. Maybe tomorrow I'll put the crank and tranny in it, and atleast get the 2 halves closed up. I got to looking at the wiseco crank I took out ( like new, with only a couple hours on it ) and I noticed one of the tin covers has alot of movement to it. Glad I went ahead and decided to get it replaced.

just re-reading some of these posts. To drive a bearing into a hole (bore), ideally (not always possible) the dirving force should be exclusively on the outer steel rim (race) of the bearing . A driver (socket) that is too small will transfer force to the inside ring (race) of the bearing. Since the resistance between outer bearing race and bore is on the outside, this will potentially put damaging force on the balls and cage. In the case of driving a bearing on a shaft, the opposite is true, you need to transfer force to the inside bearing race (steel ring), closest to where its sliding down on the shaft. I do not have a bearing driver and have used the socket trick, with the socket upside down, so the flattest side is next the bearing and its putting force on both inside and outside metal bearing housings.(any comments from others on this Ie is it bad too?) I usually try to make a puller to suck the bearings in under slow force, never a hammer/socket, unless its just a few gentle taps and then a plastic hammer at that. Just helps reduce the initial force of the blow since there is a bit of give in the system, . A vice also works to push in bearings in many applications. Get a threaded rod and big washers, stack them bolt them into a nice pancake type arrangement, You may need to grind the bolt to fit inside the bearing, or even the washers to fit the outer cage diameter. Better yet (ya we are cheap b@stards) by a metric bearing and seal driver.. Oh and 600 grit paper wet to polish things up and remove burnt or gummy oil residue and then some oil or a wee bit of moly paste. and make sure everything is clean to insure a nice smooth assebly. Even a bit of grit can cause grief.

Interesting that the shop guy (with a press no doubt) screwed up! Goes to show you that its not that straight forward. This is exactly why I don't like to buy bikes from guys that say just rebuilt! I would perfer a bike that's been running for a while and the rebuilt part is no longer a "selling" feature!

The general honda service manual is here. This is a great way to learn how things work (not model specific) http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDkQFjAB&url=http%3A%2F%2Fwww.c90club.co.uk%2FGuides%2FHonda_Common_Service_Manual.pdf&ei=bgimUcHULKqsiAKWwIHIDw&usg=AFQjCNF4wS81G03n_rDr4UqQjnDcqZRqDA&sig2=s3CMgglOST7e5lSJ80wSPQ&bvm=bv.47008514,d.cGE&cad=rja

Edited by bikedad1

Rocky Mountain ATV did a video and they used a cooler and dry ice for the bearings. It dropped right in a torch heated case like butter... I don't think you were cold enough... And took too much time...

Got the crank and tranny installed!! Used ThreeBond on the new oem center gasket. Hope it seals up real nice. I gotta say, the tusk crank puller/installer is a breeze!! Mainshaft and countershaft spin nice and free, as does the crank. So far so good, hopefully. Next is the crank seals. Gonna use the case splitter and crank installer to push the seals in. Only issue I am having is trying to gauge or find something 1mm and 2mm so I know how far to recess the seals. My feeler gauges will get me close, but not quite an even 1 or 2mm. When the manual says 1mm below surface, does that mean the flat outer section of the seal, or the "lips" of the seal be that distance below the aluminum case?

Mmmmmm....new crank:

Tonyphonepics1201_zps1fdeab3e.jpg

Goin back together:

Tonyphonepics_zps0baef1cc.jpg

measure a washer or other stuff with calipers find something thats the right thickness. better yet Calipers if you got them can also be used if you have room, by using the back end of the caliper. the metal thing that slides out!. I A Canadian dime is 1.21 mm thick (just checked). I'm sure lots of guys generally eball em! I'm darn sure Its from the top of the seal, writing side up! All agreed?

BTW nice job on cleaning the motor!

where did the crank come from?

Edited by bikedad1

measure a washer or other stuff with calipers find something thats the right thickness. better yet Calipers if you got them can also be used if you have room, by using the back end of the caliper. the metal thing that slides out!. I A Canadian dime is 1.21 mm thick (just checked). I'm sure lots of guys generally eball em! I'm darn sure Its from the top of the seal, writing side up! All agreed?

BTW nice job on cleaning the motor!

where did the crank come from?

I have a set of calipers a buddy let me use, but the measurement he said they used, wont do mm, only thousandths, I believe. Hmmm....I'll see if work has a set. I have the correct size sockets to get them in, and down over the crank ends, but I am trying to figure out the easiest way to get em in level, and to just get them in easiest. One site says use the case seprater but not seeing how that'll work on the igniton side too easily.

The engine cases look better in the pics than in person. There is still some pitting/dark spots you can see in person, but much better than before. The last owner must have never cleaned it. I used mothers polish and elbow grease on it. The crank is the oem 05-07 crank, and I ordered it and all the other parts for the bottom from service honda. The crank was $202 and some change. I had already had the new oem cylinder purchased from them before I picked this bike up. I had it as a spare for the other cr incase it needed it. They always seem to break when money is tight.

1 mm = 0.04 inches. Funny, on my pics, things always look worse than in person.

1 mm = 0.04 inches. Funny, on my pics, things always look worse than in person.

Well, got the crank seals in....The right side ( bigger seal ) might be a hair further than 1mm.....The ignition side ( smaller seal ) might not be quite 2mm ( ended up pushing it in with my hands as even as possible ). Tried installing them pushing them in with the tusk case splitter. Kept wanting to walk the socket, and was a PITA to keep the seals level. Thinking they are close though to even. Got the sprocket shaft seal in. I think its about right. Wondering who I can get to look at them and confirm if they are good to go. Hate the thought of having a shop check them out. Im sure nothing good can come of it. Just hate worrying and it will make me put off finishing up the bottom til I get someone to say they are well enough.

Thats usually the case with pics. Maybe they look ok in person, I dunno. I tend to see worse things than others notice maybe.

Edited by wykyd450r

Don't forget to preload your kickstart spring! Saw that happen to a kid and it literally broke the case. Just one of those things that gets forgotten sometimes. I honestly didn't know the first time I did it. Luckily I noticed right after I did it because the engine locked up while I was turning it by hand on the bench. Easily fixed, but not so much if you forget and slam down on the kicker one good time!

Edited by user:4

I got a bike that had a hole blown out thier too. Was not sure what cuased it. Likely was it. Also make sure you line up the marks on the on the kickstarter shaft and the ratchet gear. I think you are worrying too much, not that that is bad...fear is good, keeps us on our toes. But whats the worst that can happen with your seals? Dive in a replace one. Ya a pain, but chances are you are going to have to dive in their again for something! Good lesson from user 4 and good advice too. Make sure the thing turns on the bench, Make sure the tranny clicks through all gears on the bench (this is tricky. Leave the plug out work the flywheel. Shifting is only smooth as the engine turned over a bit each time. Make sure the clutch disengages smoothy when its on the bike. Give it several Slow kicks before you fire it up. Pay particular attention to the thrust washers and collars on the assemblies on the clutch side. The are critical for properly aligning gears. If you really screw it up, you are still ahead finincally than had you taken it to a shop. Just have the wife to contend with LOL. Now that's your biggest safety risk!!!!

I got a bike that had a hole blown out thier too. Was not sure what cuased it. Likely was it. Also make sure you line up the marks on the on the kickstarter shaft and the ratchet gear. I think you are worrying too much, not that that is bad...fear is good, keeps us on our toes. But whats the worst that can happen with your seals? Dive in a replace one. Ya a pain, but chances are you are going to have to dive in their again for something! Good lesson from user 4 and good advice too. Make sure the thing turns on the bench, Make sure the tranny clicks through all gears on the bench (this is tricky. Leave the plug out work the flywheel. Shifting is only smooth as the engine turned over a bit each time. Make sure the clutch disengages smoothy when its on the bike. Give it several Slow kicks before you fire it up. Pay particular attention to the thrust washers and collars on the assemblies on the clutch side. The are critical for properly aligning gears. If you really screw it up, you are still ahead finincally than had you taken it to a shop. Just have the wife to contend with LOL. Now that's your biggest safety risk!!!!

Yep, I think I am worrying too much. I just checked those seals again, and again........and again and again lol. They might not be exact, but they must be super darn close. I can see a gap between the inner side of the seal and the bearings. probably 2mm or so, maybe more gap. I did however begin to wonder how I can get some oil on those main bearings before starting it up. Maybe put some straight klotz down those holes? I plan to do the same on the lower rod bearing. So I am feeling confident enough to continue with adding all the parts to the right side now. I had a friend here "to hold my hand " lol while joining the case halves. After torqueing the case half bolts to 4 pounds, then to seven, we kept going around til we were certain they were good. He made a point that I keep remembering even with the seals...." It's more perfect than the shop would have made sure of "....

i agree shops do it fast! Make sure you use locktight on the bearing retainers (blue is recommended) not red... (Anyone care to verify this!). You can still put some 2-strok oil on the bearings from the top end can you not? This suspense if building. you have to post a video of you doing a big jump!

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