Sunday, February 14, 2016

The Monkey Decade: Plus Three

The operating table
The "Monkey Decade" was a series of posts I did back in 2013 concerning my Campstove Green Karate Monkey single speed. (The last update can be revisited here) The bike was purchased as a frame and fork by me in 2003, March I believe it was, and I rode it pretty religiously up till about 2007-2008 when other bikes and obligations kind of put that old critter on the back burner for quite a while. That series was a way for me to rekindle interest in the bike, and it did. There was one small detail that precluded me from getting back in the saddle with the project, as it were. That one thing was a very stuck bottom bracket that was in need of replacement.

Well, as I posted my Minus Ten Reviews, I was looking for an image, and found one of that old Karate Monkey in its heyday. (See yesterday's post) That pushed me over the edge, as I was not going to ride to work Friday in the sub-zero windchill, and I knew the repair schedule was pretty open. My boss at work is into challenges like stuck bottom brackets, so I knew he would be okay with me doing this in the dead of Winter. So, I hauled in that hulk of a Monkey and fastened it securely into my repair stand. The game was afoot!

There is one image of the process I did not get that I wished that I had. First, a bit of imagery description to help out here. I had purchased a large, 1 1/4" combination wrench which fit the Shimano bottom bracket tool quite nicely. That was all affixed to the non-drive side bottom bracket cup, (the drive side I managed to remove in 2015), and that big ol' wrench was hanging out there quite a ways. More leverage than I thought one may need. I braced myself, grabbed the frame in one hand and the heavy lead mallet with the other, and smacked away as hard as I could. That didn't work, so Andy stepped in to lend a hand, but to no avail.

By now my boss had come out and he decided that three of us could do the job. Two folks bracing the frame, me whacking the wrench with the lead mallet.


My boss stood back and said, "Where is the fork straightener?" I knew exactly what he was on about.

The fork straightener comes from a less litigious, a less carbonated time, when forks were steel and people were willing to take the risk that a mechanic's bending a fork back in plane was an okay thing to do. Nowadays it's main usage is for cases that require extreme amounts of leverage. Times like this ......

Todd had wandered in about this time to see what all the fuss was about. Then he was employed into the process. Four grown men, heaving on a four foot long lever of steel on a 1 1/4" tool affixed to a splined interface. We were pulling so hard that the big combination wrench was deflecting about two inches. Finally, it moved! We all stood back in self-congratulatory stances, as only men can do after accomplishing manly tasks. Not that women couldn't have done it, but we men have a special air about us. I think everyone knows what I mean by that........

Anyway, it wasn't loose. We broke off the splined interface!!!

Yeah........that's just awesome. Now what?!!
 Okay, so now what? Well, there was no tool interface left anymore, so a destructive technique was all that was left to me, but how? I looked at the bottom bracket and knew that Shimano had assembled it in some way, but in what way? If I could reverse the process some how, I could maybe break it down to just the threaded part which was stuck in the frame. I began to pick at it with my sharp pick set tools. Eventually, a circlip came out, then a seal. I was making progress, so I was encouraged. I eventually pulled out the bearing cage and revealed the 1/4" ball bearings in their races. Hmm......hammer time! I grabbed a ball peen hammer and whacked the end of the spindle with a few sharp blows.

The BB-UN72 bottom bracket cartridge.
It came flying out of the frame like a missle, just barely missing a bike in the other stand! Whew! That would have sucked if I had hit it. But, I didn't, and now all I had to do was to remove a steel collar which was about an inch and a quarter wide and which was threaded into the bottom bracket shell.

Yeah.....that's all I had to do. 

There was only one way that was coming out. Remember, I had no tool interface, the piece was already missing a bit of its outer dimension which we had sheared off, and getting a chisel in that tiny space was almost impossible. I tried the chisel route, but it was not really very effective. I was going to have to hack saw that bugger out of there, and in doing that, not ruin the frame! We didn't have a jab saw, so I had to disassemble a standard hack saw, pass the blade through the bottom bracket shell, and then reattach the blade to the frame of the hacksaw. Tedious, but not impossible. Now, on to cutting!

I made three, very calculated, careful cuts. Two close together, and one roughly 90° from those two. Then I used a standard blade screw driver that I had sharpened a bit as a chisel to start to split the collar at the cuts I made, and then to drive the blade under the collar, hopefully prying up the smallest bit of the circumference of the collar first. It was a slow, tedious process, but I could see that the edges were working up. Finally, it snapped up off the bottom bracket shell! Then the two larger pieces came right out as well.

The two larger pieces of the collar show how rusted they were into the frame.

I got the bottom bracket out, and cleaned up the threads of the bottom bracket shell with the bottom bracket thread chaser. Whew!

That was close.

And it took entirely way too long to reach this result, but at least now I have a frame that I can rehabilitate and rebuild into a working bicycle once again. No more hang ups. Nothing to stop forward progress anymore.

Now what.....

You know, back in 2013 I thought maybe I would put the KM back into the (mostly) original configuration that I had it in back 2003. The thing is, that configuration was short lived, and I actually liked it best in the 2005-2008 time frame when I had a Midge drop bar, leather saddle, and a pretty stout gravel grinding gear set up on the bike. I got to thinking, well.........why not do that? 

New KM's are much more capable off road machines than my '03 is.
The old KM was good for its day, but the straight 1 1/8th head tube, non-gusseted frame, and antiquated rear drop out design make for a less than optimal off road bike now compared to the modern day KM which is a better Monkey all around for single speed activities on single track.

Plus, as I looked at the old, worn frame, it occurred to me that I might be able to use a specific, "old school" style wheel set I picked up from Mike, a Trans Iowa/Tour Divide veteran a few years back. It's an XTR hubbed, Salsa Delgado rim brake style wheel set which comes right out of the same time frame that the 2003 Karate Monkey does. You may remember also that '03 Monkeys could run cantilever brakes. Plus, the Shimano SLR levers I have on the bike should pull linear pull brakes well enough, and even if they don't, I have a pair of Tektro long pull levers sitting around that will.

I figure I'll set up a fresh pair of Bruce Gordon Rock and Road skinwalls on that, and my Velo Orange leather saddle. That along with a new handle bar, stem, and a TruVativ, outboard bearing single speed crankset, and Surly cog with a 9 speed chain driving it all, and I should be sitting pretty well and have a great single speed gravel travel rig.

So, no bike project is worth doing without a goal. This bike is being resurrected at the perfect time for me to reprise the first Guitar Ted Death Ride course. The Karate Monkey single speed was the bike I used on that first GTDRI, and as we're doing the same route, why not use the "same" bicycle?

All righty then......its on. 

1 comment:

Rob said...

Nice! Glad to hear you got that troublesome BB out and are breathing new life into this "classic" frame!