1971 r50/5 sat for a decade - re starting

Discussion in 'Airheads' started by madtownadv, Aug 13, 2021.

  1. tlub

    tlub Long timer Supporter

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    We spent most of a day on it. Replaced the tires, tubes, and rim strips. Checked and greased wheel bearings. Checked air filter-looked fine. Replaced the crossover fuel line. Started in on the forks, and the rubber parts were goo, the upper bumper non-existent and I'm have an SOB of a time getting the damper unit back in from the bottom, with those three rings on it. Can it be inserted from the top? Any hints on this?
    Also, the swingarm bearing adjusting pins are not moving easily. Even with the 27mm nut all the way off, they cannot be unscrewed, and seem notchy or grating. the left will turn out about 2 turns and stop, the right about a quarter turn. The bearings appear to have no grease. I see nothing in the gap. After I pumped a bunch in there, none came out along the gap like it usually does. I fear the pins are rusted to the inner races, and don't want to force anything because I'm afraid I will strip the threads in the frame.
    Any ideas? For now, I've shot some penetrating oil in the gap and hoped for the best.
    Here's a few photos. The tires were toast, and replaced with Conti-Go tires.
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    #61
  2. Pokie

    Pokie Just plain Pokie.

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    The swing arm pins are probably rusted to the bearings and the bearings to themselves and the sleeves. Penetrating oil, tapping and running them in and out will slowly get them out. I've had to remove a number of them that had been let to rust.
    #62
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  3. tlub

    tlub Long timer Supporter

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    Thanks. You told me what I didn't want to hear, but feared was true. I'll play with them a bit.
    Now, any advice on getting the damper unit back in the fork tube?:D
    #63
  4. Pokie

    Pokie Just plain Pokie.

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    I've made a few tools for that job but you can get them back in using a piece of shim stock. If you don't have any of that, use the material from a soda pop can. A decent pair of scissors should do the trick.
    #64
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  5. Beemerguru

    Beemerguru Beemerguru...G/S guy

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    You might also add some heat to the solution. MAP gas and aim it at the swing arm ends where the bearings sit. Take your time and they'll eventually come out.
    #65
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  6. Plaka

    Plaka Brevis illi vita est

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    I have made a pinch type ring compressor out of soda can. Do not use a beer can as there is only one way to get it empty and this can affect your mechanical work.
    #66
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  7. tlub

    tlub Long timer Supporter

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    Thanks, everyone. We've had two more sessions, and I spent some time on it as well on my own. The ring compressor from an aluminum can worked really well. The damper slipped right in, especially when I lubed it with some moly spline lube. We synchronized the carbs with shorting, as there are no vacuum ports, and got it pretty close. Changed the oil to a high-ZDDP oil, changed the oil filter (it was in bad shape- the attached o-rings both came off). The rear brake was sticky, as was the brake light switch. All were cleaned and adjusted. The front brake was a struggle. I took it apart, cleaned all the pivots, and put it back together correctly (as determined by photos). It was useless. I took the brake assembly off my R75/5, and swapped. Mine worked fine on his bike. So he sanded his brake shoes, and put his back on. It worked.
    The only real issue remaining is the swingarm bearing adjusters. They are still locked (rusted?) to the bearings, but do allow adjustment. We decided that's a winter project.
    We both rode it, and it runs and rides quite nicely. The plan is to take it to Slimey Crud, and then the owner (the neighbor- remember? it's not my bike or his- we are just doing a good deed) is taking him and his wife, and me and my wife out to dinner on Monday.
    So we have another running airhead on the road!:clap
    #67
  8. Pokie

    Pokie Just plain Pokie.

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    The swing arm pivots can be a nasty job when they are rusted together. In the mean time, pump it full of grease to get things moving again. From time to time, drip a few drops of penitrating oil in the space between the swing arm and frame and over time it will start to seep in.
    #68
  9. Plaka

    Plaka Brevis illi vita est

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    Done correctly the shorting method produces extremely accurate results. But I see a lot of bad info on it and suspect people don't get what it can do because of this.
    #69
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  10. tlub

    tlub Long timer Supporter

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    I got one of them free yesterday. The other, we will work on just as you suggested. Thanks
    #70
  11. tlub

    tlub Long timer Supporter

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    Yes, I used it for decades before I had my Harmonizer. It's not a bad method. I have 3 clips on each wire so I can do dual plugged machines as well. I think we got it pretty close.
    #71
  12. Plaka

    Plaka Brevis illi vita est

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    um..."petty close" is what harmonizers get.
    #72
  13. tlub

    tlub Long timer Supporter

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    Well, I think I get it closer with the Harmonizer than with the shorting method. YMMV, but I like it better. Especially for catching the first bit coming off idle, and it's much faster. Still, I did survive and enjoy riding just fine for the 4 decades or before I had a Harmonizer, though I prefer to use one now.
    #73
  14. Plaka

    Plaka Brevis illi vita est

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    What I was getting at is I don't get "close" either. i dead on nail it. I've used vacuum methods, and extremely accurate ones. They weren't as good as balancing the power. So I gave up on them, sold the fancy (and expensive) toys I had gotten and went back to how I had learned in the first place.
    #74
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  15. madtownadv

    madtownadv Adventurer

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    These photos are long overdue.....and a big thanks to 'tlub'....

    The two of us at Slimey Crud Run https://www.slimeycrudrun.com/
    PXL_20211003_141340145.MP.jpg

    and the owner riding it for the first time in 17 years....
    PXL_20211004_192901741.jpg
    #75
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