COLUMBIA BUILT BAR HOPPER

Discussion in 'CLASS 2 - WINTER BUILD JOURNALS 2019' started by Reallybigtim, Dec 5, 2019.

  1. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    Still struggling to figure out what kind of chainring/chainguard combination to use for the Bar Hopper. I want to try to get a smaller Columbia 5-spoke ring. I have had a few ideas for a guard but nothing that has jumped out at me as "the right one". It's gotta have the right attitude. Ideas or suggestions appreciated.
     
  2. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    I cannot believe that nobody asked if those 3" tires rubbed anywhere. THEY RUB EVERYWHERE! Now, my challenge, is to successfully make them clear everywhere! It looks like I can modify the springer easily enough to provide enough clearance by moving the strut rods to the outside and shimming the fork legs at the lower attachment points. If my bike-tech buddy can get these old wiggly Huffy rims perfectly true (which he guarantees he can do successfully), I will have enough clearance of the rear tire near the seat post (about 1/32" per side). The problem is the rear frame width down by the bottom bracket. I think my only options are to shave the sharp side edges of the tire down a bit. Or carefully spread the frame slightly (which I don't like doing). I could use narrower rims, but I don't consider that to be an options because it just wouldn't look right. Ideas and/or suggestions from the veteran builders here would be greatly appreciated.
     
    Last edited: Jan 1, 2020
    RustyGold likes this.
  3. rrtbike

    rrtbike

    Joined:
    Jan 12, 2014
    Messages:
    1,251
    Location:
    Atlantic Iowa
    Very few frames will hold the 3" tires. I have only really come across a Huffman built 20 incher that didn't rub.
     
    Reallybigtim and sandman like this.
  4. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    These tires are so close to fitting into this cool old frame, that I have to try to make them work. I have decided that spreading the lower rear frame area is not an option. I can almost guarantee that the chain will rub also. Shaving (or sanding) that sharp side-edge off of those sidewalls and getting the rims absolutely true will hopefully be the solution to both of those fitment issues.
     
    Last edited: Jan 2, 2020
    sandman and OddJob like this.
  5. OddJob

    OddJob

    Joined:
    Mar 26, 2012
    Messages:
    6,743
    Location:
    Maplewood, MN
    RBT, I have used that same tire in a 26" size on a build, Hawth Rod, in the past. I got by with using a dremel and just taking a few layers off the chain stay / seat stay to make it fit. And yes, spot on trued rims are absolutely necessary!

    There is a lot of rubber on that protruding edge, and I would not be afraid of grinding some of that off either. Take it slow, a little bit at a time.

    What psi are you running in the tires? I have found that even 5 - 10 psi less than max will allow the tire to fit in tight spaces, and provide a better, cushier ride quality. So, a 40 psi tire pumped up to say 32 or 34 psi might help your situation as well.
     
    Reallybigtim likes this.
  6. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio

    Great idea! Rated at 40 psi, now down to 30 psi, and they are slightly narrower. But now the tire has more flex side-to-side on the rim due to the rim being much narrower than the tire. That's why I took them to 40 psi initially. Have to find that Goldilocks pressure once I get everything else dialed in. Not going to grind any of that nice original paint off of the stays. But the rear almost completely clears now except for the yet unresolved wiggle in the rim. A good rim truing and a little bit of sandpaper to those sharp side-edges and I think everything will clear. Kudos, OddJob!
     
    Last edited: Jan 2, 2020
    OddJob likes this.
  7. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    Does anyone have a 50's Columbia 5-spoke chainring (non-skip-tooth)? I would like to use a smaller one (36 tooth?) from a girls 20" (if they actually made a small one). I have been looking for a while but I cannot seem to track one down. Thanks all!
     
  8. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    A funny note: I have to completely deflate the rear tire to install or remove it from the frame! And the axle has to be adjusted to the most rearward position for the tire to clear everything. Therefore, I will be cutting the chain to the exact correct length instead of having the convenience of axle adjustment for chain tension.
     
    Last edited: Jan 2, 2020
  9. OddJob

    OddJob

    Joined:
    Mar 26, 2012
    Messages:
    6,743
    Location:
    Maplewood, MN
    The other trick I have used is to dremel out the drop out for the rear axle. There's plenty of material there, so no worries about strength. An 1/8 - 3/16" really makes a huge difference for tire clearance.
     
    Reallybigtim likes this.
  10. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    Thanks, Lee. It's all those little tricks that can provide endless possibilities for custom building. I have modified 24" frames in this manner to squeeze 26 inchers in there. But I think I can make this one work without modification. I had actually considered making this into a 26" project by attaching 3" homemade extender brackets on the back. But the mock-up looked horrible, so the idea was canned. It just didn't look right on this long, low designed frame. Seat tube is only 12" long on this frame (very bmx-like). I have a 50's Murray 20" frame that has a 14" seat tube. It looks good with a 26" mock-up. I think I just gave away a future build-off idea.
     
    RustyGold and OddJob like this.
  11. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    A few more finishing touches to bring it all together. Headlight is a nickel plated 30's automobile cowl light with the original etched glass lens. The chainring and chainguard are Schwinn. The chainguard resembles the full circle design that Columbia used on their 50's bicycles. I am pleased with the results. It has that bratty ratty bar hopper attitude. DSCN1066.JPG DSCN1067.JPG DSCN1070.JPG DSCN1069.JPG DSCN1068.JPG
     
    Last edited: Jan 30, 2020
  12. rrtbike

    rrtbike

    Joined:
    Jan 12, 2014
    Messages:
    1,251
    Location:
    Atlantic Iowa
    Nice job on the whole thing.
    I can't see riding with the seat that low but the bike looks great!
     
  13. Dr. Tankenstein

    Dr. Tankenstein

    Joined:
    May 20, 2009
    Messages:
    6,008
    Location:
    Isle of Hope, GA
    One of my favorite builds on RRB.
    The tire size gives it a ‘punch you in the nose after a few pub hops’ look to it.
    If it wasn’t for the crank arm length, this looks like could be a 26” fat tire cruiser, the proportions are spot on.
    Love the brattitude!

    Cheers to ya!



    Sent from my iPhone using Tapatalk
     
    OddJob and Reallybigtim like this.
  14. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio

    Thank you for the kind words. It took a lot of effort to get this bike to its end point. The small headlight, small pedals, tiny chainring and chainguard were all intentional to make the bike look proportionally larger and longer. While the tall, wide ape hanger bars and long coke bottle grips were also intentional to make the bike look proportionally smaller and shorter, all at the same time. Kind of a double optical illusion to accomplish that right look. This was a fun and challenging build.
     
    Last edited: Jan 30, 2020
    SwissGuy and RustyGold like this.
  15. handyandy1100

    handyandy1100

    Joined:
    Jun 27, 2017
    Messages:
    1,074
    Location:
    Willow Spring, NC
    At first I wondered if the name "Bar Hopper" was appropriate for the under 21 crowd, then I remembered this build off is for 21 and under. LOL
     
    OddJob, SwissGuy and Reallybigtim like this.
  16. MattiThundrrr

    MattiThundrrr

    Joined:
    Jul 16, 2019
    Messages:
    1,341
    Location:
    America's Friendly Hat
    Oh you Americans, with the crazy laws...
    "Ohio state law does allow for parents to allow their children (or spouses who are over the age of 21 to allow their underage spouse) to consume alcohol, under certain circumstances."
     
  17. sandman

    sandman

    Joined:
    Nov 17, 2018
    Messages:
    594
    Location:
    NEW SMYRNA BEACH FL.
    Olympic bar hopper ?
    upload_2020-2-1_9-46-27.jpeg
     
    Reallybigtim likes this.
  18. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio

    Laws are nothing but how someone else thinks you should behave. Usually to serve their own interests.
     
  19. The Renaissance Man

    The Renaissance Man __CERTIFIED DIVER__ (Open Water & Open Dumpster)

    Joined:
    Nov 24, 2012
    Messages:
    7,864
    Location:
    The Tropics of Alabama
    Turned out awesome! Perfect stance.
     
    Reallybigtim likes this.
  20. Reallybigtim

    Reallybigtim

    Joined:
    Jun 19, 2016
    Messages:
    243
    Location:
    Ohio
    You don't know how close I came to using 4.5" cranks instead of 5.5" cranks. Just because of the proportioning effect that you are referring to..............
     
    Last edited: Feb 7, 2020
    Dr. Tankenstein and sandman like this.

Share This Page