CB200 Lower rear shock bushings

trevd

trevd

Well-known Member
Joined
Dec 12, 2024
Total Posts
62
Total likes
25
Location
Ottawa, Ontario, Canada
So far, these things are the biggest PITA or our entire 1975 CB200 "get back on the road" project.


The originals were a pain to remove, and the new ones we received from Davis Silver Spares were a bit tough to install but we managed. Then yesterday we went to bolt the shocks on and encountered another challenge... The inner diameter of the lower rear shock bushings is not large enough to allow the bolt that fits the shocks to pass through!

At first, I thought that DSS must have sent us the wrong part, but looking at other parts I couldn't figure out what they may have sent. So I measured the inner diameter of the bushings they sent me.

PXL_20260518_140712990.jpg

That's pretty close to the size needed for an M8 bolt I figured. So I measured the bolt that threads into the threads of the shock...

PXL_20260518_143954577.jpg

Which is probably what an M10 bolt measures. So the mystery of why the bolt didn't fit into the bushing is solved... now, the mystery is why is that bolt bigger? It seems that the Showa 317 (as these are labeled as) shocks weren't standard on the CB200s, and may have come off a 350 or bigger at one point. The bolt we have threads into one side of the shocks we have.

Question is, what do we do now? Do we get an M8 bolt that will fit into the bushings, with a nut on one side to hold it in place, OR do we try to drill out 1.5mm or so out of the inner metal sleeve of the bushing in order to allow the M10 bolt that we have to fit into it? Based on looking at the old bushing vs the new, taking into account the beating that the old bushing got while we tried to remove it, I suspect that when the shocks were put on they did a bit of drilling...

PXL_20260517_210613527.jpg

OR is there some other solution that I can't think of right now?
 
I would not drill out the bushing as you would be removing too much material. The parts fiche lists an 8mm bolt so I would go with that. You could try to find a locating dowel to use as a spacer for the lower shock mounts and cut to length to bring the current 10mm hole down to 8mm and use a thin 8mm nut on the outside of the threaded lower shock mount. BTW the threaded part of the shock is usually on the inside of the swing arm.

The alternative would be to get a pair of shocks with 8mm lower attachments.
 
Good idea! I didn't even know that locating dowels were a thing... I guess I could also use an M8 threaded insert to thread into the M10 threads? Again, something I didn't even know existed...

And yes, since I took those pics I realized that the threaded side of the shock goes on the inside. I initially thought both sides were threaded.

Thanks!
 
You can also just source a correct bushing. Just get the proper OD/ID dimensions at Grainger or Amazon etc. most of these things are actually pretty common sizes.

Or you can create your own with a 10mm ID x 14mm OD bushing slid into a 30?mm OD x14mm ID rubber bushing.
 
You must log in or register to reply here.
Back
Top Bottom