Crank removal

[ozzmonaut]

So this bike is apparently late teens-early twenties. This crank isn't like any I've dealt with so far. There was a little dust cap threaded into this hole, which I removed. It looks like the crank may be threaded onto a shaft which is part of the drive side crank arm. I've tried moving it in either direction to remove, with no luck . I would assume that since bikes are generally moved forward, that the forward movement of the crank would tighten it rather than loosen. But this bike had a fixed gear hub, so the dust cap may actually act as a lock nut , keeping the crank from backing off if the crank is pedaled backwards.Has anyone dealt with this type of crank and can shed some light on this so I don't waste my entire night on one futile effort?

 

[LukeTheJoker]

Never seen anything like it. Is that a Hex-Allen key bolt in the middle?

Luke.

 

[ozzmonaut]

It doesn't appear to be. I put a pedal on the inside of the opposite side crank to keep it from moving with the pedal against the frame. I put a cheater pipe on the crank to try and loosen it. It just bends the crank. I'm not sure where to go from here.

 

[ozzmonaut]

It was a washer that I removed, under that was a bolt with a square hole. I used a screwdriver to get that out, but the crank still won't come out. I'm guessing it is pressed in, so I might have to use a ball joint removal tool or something like that to get it out.

 

[LukeTheJoker]

Ouch!

Luke.

 

[OneHorsePower]

It doesn't appear to be. I put a pedal on the inside of the opposite side crank to keep it from moving with the pedal against the frame. I put a cheater pipe on the crank to try and loosen it. It just bends the crank. I'm not sure where to go from here.

well if it is bent and additional effort don't work , just use the brutal approche (Cuting disk/grinder/Torch & hamer ) :wink:

 

[ozzmonaut]

It doesn't appear to be. I put a pedal on the inside of the opposite side crank to keep it from moving with the pedal against the frame. I put a cheater pipe on the crank to try and loosen it. It just bends the crank. I'm not sure where to go from here.

well if it is bent and additional effort don't work , just use the brutal approche (Cuting disk/grinder/Torch & hamer ) :wink:

The crank was already bent, so I used the new-found info to straighten it. This thing keeps getting more complicated. I racked it back and forth with the cheater pipe and managed to get it part way out. However when I look into this (which I assume is a slot for adding oil but may have another function), I am seeing more threaded and slotted areas that don't really make sense. And it looks like this bottom bracket would accept normal cups but instead employs rubber oil seals and some odd bearing placement. I'm just hoping someone on here has had some experience with this before I start cutting. If all else fails I'll hack it and go with a standard crankset. But at the moment the extreme diffences are somewhat intriguing and make me want to get it functional as it was originally intended

 

[OneHorsePower]

can't you just work around it , like leave it there ? or it does not turn freely ? ... i painted many 3piece crank bikes in the past cause i just did not have the tool

 

[ozzmonaut]

The chainring was pretty trashed, so I need to replace it. That's my main reason. Good news, I beat it apart. The centershaft is a hexagonal tapered type. The oil seals are destroyed. The hole in the center of the chainring is much larger than normal so I may have to open up the center on the chainring I want to use. But I think I can get this thing going, at least within a few weeks. I may start a build thread for it, since I have already gotten into it pretty deep. I've already laced the fixed gear hub into some 28" clinchers, as well as rebuilding the pedals. Can't wait to see how many bottles of ibuprofen this thing costs me. :lol:

 

[frameteam2003]

Wish I'd seen this earlier! Well a waste of time now but the slot in the bottom was for a screwdriver to lock the spinal so you could unscrew the arms

 

[ozzmonaut]

That's how I got the one side off, but I knocked the drive side out with a hammer. Reassembly is going to be a whole lot easier.

 

[Euphman06]

Is that an Iver Johnson? I worked on one of those and the crank was a 2 piece thing with a fancy set up but actually pretty easy to remove one you know how.

 

[ozzmonaut]

Only has two headbadge mounting holes, one above the other, so I'd say it isn't an iver. Also I had an I.J. frame but the 2-piece crank setup was different with the bottom bracket actually being threaded.This one actually has cups that hold the loose bearings tapped into the bottom bracket.

 

[ozzmonaut]

But had I originally known about the threaded piece hidden in the center, yes, this would have been a breeze to take apart. It certainly was easy to service and reassemble.