Author Topic: Steering head bearings  (Read 308 times)

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Ronnierockets

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Steering head bearings
« on: 02 December, 2023, 19:41:32 »
Hi can anyone confirm the size of the steering head bearings in a bsa Q7
Thanks.

JABBA99

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Re: Steering head bearings
« Reply #1 on: 03 December, 2023, 16:48:41 »
The attached is from the 1936 handbook in the members area off the website (for R17-R21-W6-Q-M10) .. looks like "ball and cups" style. I would think safest to measure with Vernier or similar the frame recesses (top and bottom) and fork "spindle" diameter to check what sizes you actually have in case of wear?

Ronnierockets

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Re: Steering head bearings
« Reply #2 on: 04 December, 2023, 20:54:41 »
Hi JABBA99, thanks for your reply,
The steering stem is  1 1/8”thick  frame recesses are 5/16” deep (top) and 7/16” (bottom)x1 15/16”
Hope this helps ..
Ronnierockets

Bicycle repair man

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Re: Steering head bearings
« Reply #3 on: 05 December, 2023, 14:51:53 »
They take 1/4" balls, 18 in each race. The ones that fit in the frame have tapered sides. The top one is a top hat shaped piece. The lower one that fits onto the forks is similar to the frame ones but with a smaller ID and straight sides.
Cornucopia list them but they require a mortgage.

Ronnierockets

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Re: Steering head bearings
« Reply #4 on: 08 December, 2023, 17:28:42 »
Hi Bicycle repair man,
Prior to my post I tried different  size ball bearings in  one of the ball races and 1/4” seemed to the one.
Thanks for confirming that ,and for the information on the various pieces of the puzzle you kindly supplied.
I will have many more questions to ask as it’s a basket case Q7 I am working on .
Thanks ..Ronnierockets…