I had 2 kryptonite lock barrels that the U part was cut by some thieves with bolt cutters.
I trashed them, but then decided to keep them as evidence prints etc.
Had them laying around buried in my bike junkbox. I always loop my chain through the front wheel to prevent theft, in NYC I see plenty of bikes locked up missing one wheel.
So it occurred to me that I could use a kryptonite barrel if slightly modified.
Here are the results of my tinkering.
Step 1: Repurposing Kryptonite Lock Barrel
I decided the the easiest way to do it was to remove the brake posts from the front fork and replace them with modified bolts. I have disc brakes, so I didn't need the posts.
So I measured distance between brake posts and cut as needed.
The one on the left is the modified.
First I removed the plastic cover so i could reuse it.
Think I cut 1-3/4 inches from original barrel. I used a 4 inch grinder with a metal cutoff wheel.
Then you to cut a rectangular slot, do this after you figure out the bolt lock look at next step.
Step 2: Replace Brake Posts
Find bolt with head big enough to fit key side and when locked will not come out.
I used a bolt with a larger head on the opposite side, ended up grinding the both sides of the head
so the bolt is like a T, the images with the black bolt are T.
Being screws made it easy to adjust how snug the lock fit.
Step 3: Finishing Barrel Lock
After you have determined the distance of both bolt openings.
Mark and cut a rectangular slot for the T-bolt.
Again 4 inch grinder with metal cutting wheel, worked best for me.
Then cut plastic cover to size and reuse I used a box cutter.
Adjust bolt heights as needed.
Whoopie! no more looping chain through wheel.
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