My bike spent the better part of the summer down in the basement. I bought a pair of Demolition Medial cranks for it last summer and rode on them for a while but they were never right. The threads were machined a bit funny which made getting a puller on difficult. The face on the crank arm where the chain wheel attached was a bit crooked too. I didn’t notice the later defect till it had ruined a great HTP 25T chain wheel and broke a chain. Here’s the culprit:
Either way I got pissed and took the whole bottom bracket apart then left it sitting on the stand for a few months. The summer was super busy so I kept putting it off but eventually I couldn’t take the sad sight of it any longer:
I picked up a set of Macneil Conjoined cranks with bearings to match the 19mm spindle. The Macneil hubs I’m running now are great so I figured I’d make a safe bet and give their cranks a go. Paid off so far:
I still can’t figure out why all of the threads are painted. I didn’t take a picture of the threads for the pedals but they were painted a few millimeters deep like the opening for the spindle. Likely it’s just cheaper to make them that way but it makes the first installation a pain.
So now that all the parts were together, next was pressing the bottom bracket. With the right tools this doesn’t take much effort. At one point I had made a cup press from a long threaded bolt with washers and nuts at each end. It did the trick but eventually I bought the Park Tools equivalent. It’s pretty much the same thing but with handles on each end coated in blue plastic with “Park Tools” stamped on it (I’m guessing that’s why they cost $60, not worth it!):
This is the whole bottom bracket kit lined up on the cup press. Crappy thing about this press is that the handles can’t clear the frames chain stay completely so you end up with about 2 millimeters of bearing stuck out when the press can’t be turned any further:
That’s why we keep a stack of extra washers around. Stack these on either end of the cup press between the plates and you’ll get enough clearance to press the bearings flush:
Once the bearings are pressed it’s just a matter of putting the new spindle in and fitting the cranks on with a chain wheel. It’s always a pain to get the spacers right so that the cranks clear the chain stays and the chain line is straight. I’m pretty anal about this so I always end up taking the drive side crank arm off and putting it back on a few times. It’s a curse. In the end when it’s all back together it looks something like this:
I’m pretty happy with the Conjoined cranks so far. I’ve been riding on them for a few weeks now and they’re as solid as any cranks I’ve had in the past. I wouldn’t consider this much of a stress test though since I pretty much just roll around and try to keep from hurting myself so YMMV.
I’m still pretty pissed about losing that 25T chain wheel caus of the Demolition cranks being crappy. I picked it up at an Easter Boarder shop out in Massachusetts. There’s this guy out there that machines them himself under the name “Home Town Products”. Last time I was out that way he said he wasn’t making them anymore so that’s a loss.
In the background of the first picture you can see a yellow road bike frame sitting on my basement floor. That’s a my winter project. It spent the past year+ sitting outside on a sort-of covered porch so it’s in need of some rehab. More on this later.
technomasochism 