Honda CRM250R, Mark I.

Discussion in '2 smokers' started by A_Vasiliev, May 12, 2019.

  1. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    Thanks for the kind words. I'll definitely give it a look. I think if I can't find something I need there, I'll ask you :lol3
    #21
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  2. Harvey Krumpet

    Harvey Krumpet Long timer Supporter

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    I wouldn't ask me anything, my mechanical ability is limited to basic maintenance, done badly.

    Being a Japanese home market bike, loads of stuff is available for them in the land of the rising sun. The only place I could find an FMF Gnarly pipe for mine was in Japan. I found one, on the whole of the internet..

    During the enduro it became apparent that I need a bigger main jet to get the full top end with the FMF, bit fluffy at high revs but serious torque from the bottom and mid range, lovely motor.
    #22
  3. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    Mornin' all. Going to upload a progress report while I have my coffee and before I actually have to start doing my job.

    Played around with the soda-blaster some more. Really is a wonderful tool for cleaning stuff up - look at what she did to my carbon'ed up cylinder head! I really only wish I could get a cabinet for it so it's a little cleaner and more convenient to use it.
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    The soda blaster even takes off 30 year old powdercoat/paint pretty easily - funny thing is it leaves decals untouched more or less. Pretty wild. It also strips off that grey undercoat if you hit it in one spot long enough. It would take me forever to do the entire frame down to bare metal with the soda blaster though so the frame is getting sent off to an actual sandblaster for cleanup before I take it to powdercoating.
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    With the power of a flashlight and my eyes I realized that I am an idiot and was hitting the wrong lip with my punch while trying to drift the steering stem races out. Hitting the correct lip and some heating gave me much better results. A set of roller bearings from All Balls is on the way to replace the notched up old ones.

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    This shift shaft is long, skinny and hangs a little to the left. Microfiches tell me that this part number wasn't used anywhere else, so it's not like these things are all over the place. You can't get a replacement from Honda either. I'll try to bend it back with a shop press or something for a temporary fix, it would be cool to get a permanent replacement, but short of just physically comparing shafts and maybe finding one that's close enough, I'm not sure how I'd go about getting one.
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    New tool! Always a good time. My shop now has an impact wrench, which made short work of that rotor nut that I've been trying to remove for like 2 months with hand tools. Sometimes all you really need is just the right tool.

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    Behind the rotor, the stator and case were filthy. Oil and sand all over everything. I cleaned it up with my spray gun full of white spirit - much cheaper than buying degreaser or using something like carb cleaner in an aerosol can.

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    Balancer shaft pulled out. Amazingly enough the needle bearing doesn't seem to have shit the bed and therefore the shaft itself isn't damaged, so I may not have to toss the balancer mechanism entirely.

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    #23
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  4. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    Big day recently - cases finally splitski and tranny pulled out. All the shifty bits look to be in good shape, forks aren't bent or worn out, drum looks like it's doing good, gears aren't damaged.
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    Pulled out a lot of the bearings already. Some of them were really rough, visibly worn out, some were still operational, but I figured I'm already in here replacing stuff, might as well do all the bearings for peace of mind, right? Same idea with seals.
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    The rear shock ended up being "rebuildable" after a fashion after all. I can't find a replacement piston head unit but I probably don't even need one - the inside looks to be clean and relatively unworn, so I'll just reassemble with fresh crush washers, refill it with new shock oil, nitrogen, and call it a day.
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    I haven't done much to the bike in the past week or so apart from sitting online for hours looking at parts. Some of the parts that need to be replaced, some of the bearings, etc, are so rare that you simply can't find them anywhere and if you can, they cost an exorbitant amount of money, so I've been combing online resources looking for information on what alternatives, replacements, and such you can use. Reading data sheets on bearings to see if there's something special about an SC0394 that an LR203 won't do, etc. It's fascinating but also really, really frustrating at times.

    I have spent about $200 on seals and bearings so far. Mostly swingarm, linkage and engine bearings. Some of them will take a few weeks to arrive so I've also started looking at potential options for a second bike I can buy and ride while I'm rebuilding this one.
    #24
  5. Harvey Krumpet

    Harvey Krumpet Long timer Supporter

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    Good work!

    I had the motor on my DT230 Lanza re-built a couple of years ago and the mechanic was adamant that all seals, bearings etc were replaced. His comment was that it's the $1 part you don't replace which will fail. Wise words.
    #25
  6. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    I've been a little busy around the house and work to really devote a lot of time to the CRM lately, but one of the things I did purchase fairly recently was a bench grinder and some Scotch Brite discs. I started by cleaning up some minor parts and was pretty amazed at how fast and how well it turns 30 year old grime covered corroded aluminum into nice shiny parts.
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    The swingarm is clear anodized so I decided against really going ham on it with the ScotchBrite wheel (well, also because while it's a bit rough it's still plenty shiny). The fork triples and legs seemed to be the only other real big part of the bike that were polishable so I decided to go for those. The top triple needed to be paint stripped first, but it shined up OK I think. It's a bit of a rough casting, I could sand it out and make it smooth but I honestly do not care that much. A bit of shine is all I need. Bottom triple was unpainted so it went a bit faster. The fork legs themselves look the longest due to their sheer size and the amount of dings and oxidation on them was pretty incredible but they're back to good shape now - all that's missing is a couple big SHOWA stickers and we're good to go.

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    I'm currently in talks with a few different powdercoaters to see who'll give me the best price and turnaround time quote. One of the nice things about living in Russia - labor is cheap so powdercoating prices were surprisingly low, something like $90 to both sandblast and powdercoat (base + clear) the frame and rear shock spring using two different colors.

    Stay tuned and thanks for watching.
    #26
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  7. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    Went to the shop last night, mostly worked on the pitbike (wheel bearings, new tires, new brake pads) but I also slapped on these stickers while I was there.

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    #27
  8. Harvey Krumpet

    Harvey Krumpet Long timer Supporter

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    I fear when you are done this bike will never get dirty again. :D Nice work, I'm really looking forward to seeing it finished. Might even be inspired to pull mine to bits over the clay season.
    #28
  9. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    You're not the only one, I also fear once I'm done, it will turn into a bit of a trailer queen because I'll be too scared to dump it on it's side on a rocky hill.

    We'll see, though. There's always more bikes to buy!
    This is what I'm currently riding while the Honda is in a million pieces. Little 125cc pitbike I picked up used for $450 or so. Just put fresh tires on it, tore the drive chain yesterday so putting a new chain on her today.
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    #29
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  10. Harvey Krumpet

    Harvey Krumpet Long timer Supporter

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    I hear you. The temptation to go a bit nuts is strong but then I think about all the bits that are unobtainable, tempers my throttle hand and the scenery I ride on.

    Having said that, my bike has had a few quite big bins with no damage, old school Honda's are pretty tough. Unlike me.

    If I baulk at something on the CRM, I go back and throw the trials bike at it. :-)
    #30
  11. A_Vasiliev

    A_Vasiliev Red, white and blue.

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    Frame and rear shock spring are back from the powdercoaters! The frame is RAL Traffic Red and the spring is RAL Signal Blue, both have a coat of clear over the top of the color coat.

    All in all I have never seen a more beautiful motorcycle frame. If anything this makes the fear I feel in regards to dinging the frame that much worse. I'm going to need a skidplate, a pair of lower frame protectors...

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    She is a beaut, though.
    #31
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