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  1. #1
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    90s Trek 820 Refurb

    Garbage picked a 90s Trek 820 in my neighborhood. Needs some TLC. Gonna paint it and refresh it to make a beater town bike. Also going to ditch the FD and shorten the chain to make it a half assed 1x7 by keeping front fixed on smaller ring because the FD is frozen. Has some Shimano GS200 components. RD is salvageable.

    What’s the cheapest bottom bracket and crank set I can put on this bike? I’m having trouble identifying sizing. It’s a tapered square B.B. What tools needed to remove?

    Trying not to spend much of anything on the bike as it’s prob not worth more than $50.

    Any info appreciated

    Thanks
    Mike


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  2. #2
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    why swap the cranks/BB ? are they not working?

    I would leave the F der, leave the 3 rings, and put the chain in the middle ring. Set the F der limits to help lock the chain in place on that ring.


  3. #3
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    Yes, why swap cranks and BB?

    It's also possible to swap cranks and leave BB in place, as long as it's the same taper standard. Well, you can actually mix some taper standards, see here:
    http://www.sheldonbrown.com/bbtaper.html

    If you want to service or remove the BB, you need to see if the cups have splines on the inside, or notches on the outside. You need to take a picture and measurements of the notch or spline spacing to figure out what tool you need.

    Here's some unfriendly reading that will make your head hurt:
    http://www.sheldonbrown.com/tooltips/cartridge.html
    http://www.sheldonbrown.com/bbsize.html

    You'll also want a crank puller to get the crank off the spindle. I actually have an old crank puller, but I can't sell it because my town bike still uses square taper.
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  4. #4
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    I pulled a similar bike out of the neighbor's garbage earlier this year. Had to buy a cheap 26er wheelset for it since those were missing. Replaced bar/stem/shifter/rearD/chain/tires/saddle with spares from the used parts bin. Everyone said make it a 1x, but I don't see the point in changing the front. I may want to be able to shift that if I ride it to work. Perfect beach bike for about $50 in parts. BB bearings are crunchy so I may have to replace those at some point but I won't unless it gets real bad.

    Unless there is rust or issues with a particular part I wouldn't bother replacing or painting the frame. For a beater, looking like crap is a good thing - less chance of getting stolen.




  5. #5
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    It really just needs new crank set...the crank sprockets are bent and it's sorta oval looking when you spin it and look. Maybe it will function fine for now, but I'm just trying to gain knowledge on what parts I'd need in case I come across something cheap I can make a move on it.

    Good idea on using the FD as a chain guide sorta

    Frame was pretty nasty looking so I'm gonna give it a light sand and shoot it with a rattle can for $4.

  6. #6
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    Quote Originally Posted by ADKmike View Post
    It really just needs new crank set...the crank sprockets are bent and it's sorta oval looking when you spin it and look. Maybe it will function fine for now, but I'm just trying to gain knowledge on what parts I'd need in case I come across something cheap I can make a move on it.

    Good idea on using the FD as a chain guide sorta

    Frame was pretty nasty looking so I'm gonna give it a light sand and shoot it with a rattle can for $4.
    Be wary of the 200GS crankset. I actually had one on my first bike back in the day. It has Biopace chainrings, which is why they are oval. They are steel and not removable from the crank.

    The kicker is that the crank itself is steel coated in plastic. Exceptionally heavy. Mine seized to the bottom bracket taper and the crank removal threads striped out when trying to remove it to put on a LX crank. It had to be cut off. Ooops.

    To add insult to injury, the spacing on the crank is traditional "wide profile", it uses a wide bottom bracket in the 125mm spindle range. Most decent square taper cranks made after about 1992 are "low profile" and use 107 to 113mm bottom brackets. The '93 LX crank I was trying to put on needed a new BB. Double Ooops.

    So, you're likely going to need to scrounge up a complete bb/crank/ring combo. But it will be worth it because almost anything is an upgrade. Something that can take a 104mm narrow-wide ring is preferable. Bottom bracket is likely 68mm threaded but is easily measured. You could conceivably find a 80's LX, DX or XT crank and drop that on the existing bottom bracket, but it's likely to be decent money for one in serviceable condition with rings that aren't shot. Maybe a Deore Hollowtech 2 with a narrow wide from somebody who upgraded.

    Good luck.

    Last edited by Jonny Snow; 07-11-2018 at 10:38 PM.

  7. #7
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    Quote Originally Posted by Jonny Snow View Post
    Be wary of the 200GS crankset. I actually had one on my first bike back in the day. It has Biopace chainrings, which is why they are oval. They are steel and not removable from the crank.

    The kicker is that the crank itself is steel coated in plastic. Exceptionally heavy. Mine seized to the bottom bracket taper and the crank removal threads striped out when trying to remove it to put on a LX crank. It had to be cut off. Ooops.

    To add insult to injury, the spacing on the crank is traditional "wide profile", it uses a wide bottom bracket in the 125mm spindle range. Most decent square taper cranks made after about 1992 are "low profile" and use 107 to 113mm bottom brackets. The '93 LX crank I was trying to put on needed a new BB. Double Ooops.

    So, you're likely going to need to scrounge up a complete bb/crank/ring combo. But it will be worth it because almost anything is an upgrade. Something that can take a 104mm narrow-wide ring is preferable. Bottom bracket is likely 68mm threaded but is easily measured. You could conceivably find a 80's LX, DX or XT crank and drop that on the existing bottom bracket, but it's likely to be decent money for one in serviceable condition with rings that aren't shot. Maybe a Deore Hollowtech 2 with a narrow wide from somebody who upgraded.

    Good luck.

    Yes that's exactly what my crank looks like. Thanks for the info that's good to know.
    I'll post some pics when I get a chance. I'll likely need some more info from you guys...thanks!

  8. #8
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    Quote Originally Posted by ADKmike View Post
    Yes that's exactly what my crank looks like. Thanks for the info that's good to know.
    I'll post some pics when I get a chance. I'll likely need some more info from you guys...thanks!
    Happy to help. While I know it's just a beater bike, the 200GS parts are really complete crap, even by early 90's standards. They came on bikes around $300. The brake canti's are steel coated plastic, weak and hard to adjust. The derailleurs are just cheap and hard to keep in adjustment. The controls are old style rapid fire (non plus) with comically large brake levers. I had upgraded all those parts after about a year of owning that bike.

    You may want to start scrounging around for free parts, almost anything is an upgrade. V-brakes for sure. Maybe a donor bike with a broken frame could be found.

  9. #9
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    Omg I hated those bikes. Barely functional out of the box and god help me if people “mountain biked” with them. Totally destroyed. Then you got the pissed off owner who spent a fortune on a bike that didn’t last ($329 or something). Finally we just stopped carrying the low end mountain bikes.


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    I rip the groomed on tele gear

  10. #10
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    Yeh I know it’s low end - but will make a good beater town bike. Plus it was fun to refurb.

    All finished up! Currently in 1x7 mode on an old worn out 9 speed chain I had. Should be plenty enough for what I need it to do...

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  11. #11
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    Sweet 944

  12. #12
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    Quote Originally Posted by Self Jupiter View Post
    Sweet 944
    Thanks...have had it for 17 years

  13. #13
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    Forget the 944, dude has a lift and tool cabinet that gives me a giant boner!



    And yes I like classic Porsches too, but having an awesome garage to work on them seems even more out of reach to me ...
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  14. #14
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    looks good cleaned up.
    j'ai des grands instants de lucididididididididi

  15. #15
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    Quote Originally Posted by ADKmike View Post
    Garbage picked a 90s Trek 820 in my neighborhood. Needs some TLC. Gonna paint it and refresh it to make a beater town bike. Also going to ditch the FD and shorten the chain to make it a half assed 1x7 by keeping front fixed on smaller ring because the FD is frozen. Has some Shimano GS200 components. RD is salvageable.

    What’s the cheapest bottom bracket and crank set I can put on this bike? I’m having trouble identifying sizing. It’s a tapered square B.B. What tools needed to remove?

    Trying not to spend much of anything on the bike as it’s prob not worth more than $50.

    Any info appreciated

    Thanks
    Mike


    Sent from my iPhone using TGR Forums
    didn't read the thread, but I've done a few of these (commuter/townie from that era mtb), and the best resource for parts and tech info was Sheldon Brown's site.

    You can still get a nice sealed square taper BB for those. Honestly, if yours ends up being like all of mine, you'd benefit from starting from scratch with a good wheelset ("brutal beast" rhynolyte with deore hubs are readily available and have been good to me) and new brakes and cables. I'm heavy, so old wheelsets with stuck spokes making it impossible to true wheels with rim brakes aren't worth the savings.

    Square taper cranksets are all over ebay and easy to work with. You'll want to get a puller. There's a bottom bracket tool for those older ones, and a different one for the newer ones you'll replace them with. They're no big deal, and instructionals are available on youtube.

  16. #16
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    ]
    Quote Originally Posted by evdog View Post
    Unless there is rust or issues with a particular part I wouldn't bother replacing or painting the frame. For a beater, looking like crap is a good thing - less chance of getting stolen.
    I really dislike when people take an older bike and rattle can it. The bike goes from an old warhorse with beausage and character to "stolen and rattle-canned"....imho.

    [Beausage] > [rattle can job] every time.
    https://accidentalrandonneur.wordpre...lled-beausage/

    My wife rides and commutes a similar 820 "antelope" every day. Yeah, it's heavy...it's not a racing situation.


    Out of the bikel-recycle pile, the bike got that rhynolite wheelset, a new 7 spd cassette, cables all around, new friction shifters. V-brakes pads and levers, tires, and chain, f/r racks and fenders, and stem/bars/grips to fit. Big stupid cushy seat.
    One of the only remaining stock parts is that supposedly-problematic biopace crankset, which remains serviceable. I have had parts ready to replace it for 3 riding seasons now and still no need.

    Click image for larger version. 

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  17. #17
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    Quote Originally Posted by detrusor View Post
    Omg I hated those bikes. Barely functional out of the box and god help me if people “mountain biked” with them. Totally destroyed. Then you got the pissed off owner who spent a fortune on a bike that didn’t last ($329 or something). Finally we just stopped carrying the low end mountain bikes.


    Sent from my iPhone using TGR Forums
    The frame/fork are a fine starting point for a commuter. Selling that style of bike to be ridden athletically on trails seems weird at best....but those old rigid mtb frames make a fine utility/light-touring bike if you hang good parts on them.

  18. #18
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    Quote Originally Posted by ill-advised strategy View Post
    The frame/fork are a fine starting point for a commuter. Selling that style of bike to be ridden athletically on trails seems weird at best....but those old rigid mtb frames make a fine utility/light-touring bike if you hang good parts on them.
    Exactly. My SO has similar vintage bike setup very similar to IAS's. It's rad because its an old little known brand -- Muddy Fox -- with purple paint and yellow decals. Super functional town bike: 3x7, upright bars, small front rack and a nice wald basket. Sprung Brooks saddle is probably worth more than the bike. Perfect for rides to bars, grocery, light rail (which she then takes to work), or dinner.

  19. #19
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    i would normally agree about the spray paint but if it’s a grocery getter away from the city it doesn’t bother me. i wouldn’t ride around on a sprayed bike in nyc, seems like bad karma
    j'ai des grands instants de lucididididididididi

  20. #20
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    Yeh it might be hard to tell by the pic but it was pretty rusty and shitty and the previous owner sprayed multiple parts of the bike with undercoating including the sprockets and cranks so it was kind of a mess. I cleaned it up with a wire wheel....then had to paint the thing so I made it my wife’s favorite color...


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  21. #21
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    Quote Originally Posted by SchralphMacchio View Post
    Forget the 944, dude has a lift and tool cabinet that gives me a giant boner!



    And yes I like classic Porsches too, but having an awesome garage to work on them seems even more out of reach to me ...
    Ha don’t be fooled old 944s can be had on the cheap....just need to know how to fix them yourself to keep them cheap....


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  22. #22
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    Right. It’s the garage space, tools and time that are the premium, not the car!

    And a 2.7 RS ducktail is still my favorite fantasy collector’s car.
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

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