the stupid one
Über Member
- Location
- NWUK
Me again. I chose this username well.
Today, for fun, I decided to take apart the cranks and bottom bracket on the mongrel bike. Plan was to follow a YouTube video, clean everything up, replace the bearings, and get it all back together.
Turns out the crank arms aren't keen to be going anywhere. They've been left overnight in the warm embrace of penetrating oil, and if they don't want to move tomorrow then I'm calling it off, except that while I was up-close and personal I noticed these cracks and deformities in the middle chain ring . . .
Excuse the dust. It seems that there are two pairs of these, opposite each other, and with four teeth between each split, and there's what looks like a drilled hole at each split, suggesting the split is deliberate and the hole is there to prevent it continuing.
So is it a feature to perhaps aid the movement of the chain on/off the ring, or do I need to replace the entire works?
I had the bloody thing on the garage floor this afternoon while I wrestled with the cranks - crank-puller, heat gun, mallet, the works. There's a good thread somewhere here that I pored over whenever I was getting my breath and temper back. Fun. I did it for fun.
Thanks,
Steve
Today, for fun, I decided to take apart the cranks and bottom bracket on the mongrel bike. Plan was to follow a YouTube video, clean everything up, replace the bearings, and get it all back together.
Turns out the crank arms aren't keen to be going anywhere. They've been left overnight in the warm embrace of penetrating oil, and if they don't want to move tomorrow then I'm calling it off, except that while I was up-close and personal I noticed these cracks and deformities in the middle chain ring . . .
Excuse the dust. It seems that there are two pairs of these, opposite each other, and with four teeth between each split, and there's what looks like a drilled hole at each split, suggesting the split is deliberate and the hole is there to prevent it continuing.
So is it a feature to perhaps aid the movement of the chain on/off the ring, or do I need to replace the entire works?
I had the bloody thing on the garage floor this afternoon while I wrestled with the cranks - crank-puller, heat gun, mallet, the works. There's a good thread somewhere here that I pored over whenever I was getting my breath and temper back. Fun. I did it for fun.
Thanks,
Steve