BBSHD 73mm problem: rotating like a pendulum

[Stu Summer]

Louis, that is a great idea! Do you have one handy to measure? How thick is a lock ring? (I'd rather not disassemble my BBSHD to find out.

Bicycle365, thanks for the pipe wrench idea, I should have thought of it!

[Stu Summer]

Hey, everyone, a pipe wrench works just fine to tighten the bbshd lockring. Plenty of leverage and grips very well. No more pendulum swing. Before I discovered this, I ordered one of the Hozan wrenches Louis recommends. Turns out it takes 6 weeks for shipping from China, so you might want to try the pipe wrench in the meantime.

[Louis]

Louis, that is a great idea! Do you have one handy to measure? How thick is a lock ring? (I'd rather not disassemble my BBSHD to find out.

Bicycle365, thanks for the pipe wrench idea, I should have thought of it!

5MM perfect for the 68-73MM kit in a 68MM BB.

[spinningmagnets]

I noticed at a large hardware store that in the heating and ventilation section, they had 6-inch diameter hose-clamps, just like the common automotive hose clamps, where a bolt being turned activates a worm-screw and tightens it down to about 5-1/2 inches ($2). I "think" it might fit around the BBSHD motor, and doing that would provide a strap for a two-inch diameter automotive hose clamp, to hold that 6-incher up against the downtube (2-inch hose clamp as an example, use whatever diameter fits your frames downtube)...

two interlinked hose clamps, connected like a chain...pulling the motor up against the downtube.

Just an option...

[Louis]

There is a hardware solution in the pipeline, being tested. Soon to be revealed. Apparently there are applications where the drop is prevalent and a solution is needed.

[JayC]

There is a hardware solution in the pipeline, being tested. Soon to be revealed. Apparently there are applications where the drop is prevalent and a solution is needed.

Kewl. I have a big black zip-tie wrapped around my motor now for insurance - BSSHD motor fins make for great zip-tie registration slots. Interested to see what comes up for a better mouse trap.

[HD Rockhopper]

The "Better Mouse Trap" is the OEM solution.
If you use a proper tool that engages all four notches at once, and tighten it as hard as a decent sized adult can, it will never move again. Mine USED to be a problem, now that I got it super tight, it has not moved in weeks of aggressive off road riding.

[Louis]

The "Better Mouse Trap" is the OEM solution.
If you use a proper tool that engages all four notches at once, and tighten it as hard as a decent sized adult can, it will never move again. Mine USED to be a problem, now that I got it super tight, it has not moved in weeks of aggressive off road riding.

Unfortunately there are application where the help IS needed. It may not be your build, and I don't agree that JayC has a problem that can't be solved by proper spacer placement. However, that's his choice and there are builds that do need the better mouse trap. I can't reveal the application since the testing continues and it would reveal the project to the copy cats. However it will be obvious when released. And then even those that insist on a spacer under the fixing plate can have a solution.

If I've learned anything in my 3 years it's that there's always something else to learn. If Eric stopped learning we'd have no Lunacycle.

[HD Rockhopper]

I stand corrected. I forgot to consider builds that require spacers under the fixing plate. Some more extreme solution may be in order for those builds.

[rjs907]

Im putting a bbshd 120 mm on a 100 mm bb.I only have the frame and motor so far so I have to envision what the chainline might look like.

When i center the unit up to keep the drive side barely clearing the chainstay,which makes me have to shim about 8 mm. It leaves about an 1/2 inch of unthreaded shaft visible on the non drive side. The fixing plates inside diameter is a shade smaller than the unthreaded shafts outside diameter which doesnt allow the fixing plate to slide all the way down the shaft.

I had planned on using a dremel to shave a tiny bit off the inside diameter of the fixing plate to allow it to come in contact and bite into the bb, Then put spacers to fill the gap on the outward side of the plate .I will wait and see when i get the wheels and cassette to see if i can cheat it out further without getting the chainline too far out of whack.

Just another possible fix to anyone else having this situation.

[bigall123]

Well I have the opposite problem with my bbhd. I am trying to fit a 68mm to a 73mm bracket. I just can't get the 5mm thick bolt spacers any were.