A10 rear top sidecar mount

[Mitch77]

Hi all, looking for guidance on the rear top mount A10 to Monza, the guys at Watsonian are sorting me some fixings but the rear top seems to be causing concern, I note that Roy C posted some pics back a while with the the eye bolt going through the tool box bracket and frame, this hole is 5/16 and Watsonian say that 5/16 is not man enough and should use nothing smaller than 1/2 “ so my question is can I drill this hole to 1/2” or is there an alternative mounting point ?
Any help gratefully received
Thanks Dave

[idie]

I will look tomorrow and see what fitting is on my Steib which was on my B33. The Steib is under the bench with the fittings still on it i think.

[DAVE BRADY]

Hi Mitch77,

If you look just under the front of the seat where the top tube of the frame meets the seat frame you will see a square/oval hole.  There is a block that attaches here that has a long threaded piece though it with an eye on the end.  The fitting that attaches to the rear part of the chassis attaches to it.
The attached image is the best I could find and I think the item circled is it.
It is from Owens Motorcycles, Wales.  tel. 01978 266087

Dave.

[idie]

Yes you are right the frames for the a10s have that. I will have a look at my Shooting Star tomorrow to see if that has it. I know my B33 frame doesn't, I had a clamp that went around the frame. Somewhere in my garage I have a some sidecar fittings.

[Mitch77]

Thank you guys much appreciated

[DAVE BRADY]

Hi,

I have found an image that may help.
The 'block' that goes under the front of the seat can just be seen behind the choke lever.
However, if you are using a non-standard screw on filter then it will get in the way and a clamp on fitting may be a better choice.
The tool box bolt position is, in my opinion, quite strong enough but use a good quality bolt and a spacer inside 'shocky' mount plates prevent distortion when tightened up - one advantage of using this is that the tool box is more accessible.

Dave.