Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Wow - A message for 3 Wheeler owners from MMC

Any Morgan response to this worthwhile suggestion to address a serious issue ?

I have had a response from Morgan, who say that due to a specification change in the material and dimensions of the tubes from which the chassis is made, there is no need to use the modified bracket on later chassis cars. This was a specific enquiry about my car which first had a chassis replacement done in France in 2017/8 but was redone in the factory in 2018 and I don't know if the original replacement chassis was reused or not (there was some question about the original replacement chassis having been damaged by being dropped). I don't therefore know from which date of chassis, the "no modification required" runs from. In other words is it the Mk.2 chassis or the Mk.2A chassis?

I still am not comfortable with trusting my life to an unbraced butt welded ear as a suspension mount and certainly would not have accepted that on any of the cars I have used in competition over the last 50+ years. If I was doing track days/hill climbing/racing or anything like that (I am not), I would redesign this suspension support to have a semi-circular cup which could then be welded around half of the vertical chassis member, thereby spreading the stress and weld in triangular bracing gussets from the rear of the vertical chassis member to the longitudinal. At the moment I will just inspect weekly, as without removing all the coating to do NDT, there is little other one can do in the way of being proactive.

Wilson

A sad situation Sir but thank you for your prompt and detailed response. Useful for all M3W owners
Good luck with your vehicle.

I have just ploughed through the massive tome from the UK Motor Sport Association of competition vehicle build rules and all butt welded suspension mountings should be braced or gusseted. The M3W in theory therefore, could not be used as is for motorsport if you had a fussy/knowledgeable scrutineer.

Wilson

Ouch! Although it is notable that MCC do not (AFAIK) have a competition M3W5sp. Meanwhile I am wondering if the fuel tank mount crack issue is another recall-worthy roadworthiness concern for MCC to consider. But I may be biased as I'm a victim of that fault!

Have you ploughed through the ACU rules Wilson?
They are the governing body for 2 and 3 wheelers

Graham,

I looked the ACU rules first as they are far simpler and well indexed on line. They say pretty much the same for butt welded suspension pick up points. I was looking at a Youtube video of Michael Waller building a trials Royal Enfield 350 Bullet and I noticed he had braced the rear suspension mountings, where the loads will be far less than on an M3W lower wishbone arm.

Wilson

Thanks Wilson,
Anything ACU is well indexed compared to that from what is now Motorsport UK!
Just checking, but figured you would know what was applicable. Unfortunately I won't see any of our scrutineers for a couple of weeks, but I know the right one to have a quiet chat with :-)

Graham,

The rule about bracing of butt welded suspension mountings on competition vehicles, strikes me as an eminent application of common sense. I will be very interested to hear what your friendly scrutineer has to say.

Scrutineers often have their own pet foibles. When my 911 RSR was last scrutineered on the Scottish Malts Rally, the scrutineer was whingeing about the size of the brake rotors, the six pot front calipers and 4 pot rear, which are 100% correct, as the base vehicles on which the 3.0/3.3/3.5 litre RSR's can be based, the 74-76 3.0 RS or as in my case, the later but very similar 3.0L 1977 911S Lightweight Competition, both were fitted with the large Porsche 917 spec brakes as original. He then either missed or was not concerned that I am using electronic digital fuel injection rather than mechanical, because it nearly halves the fuel consumption, so I don't need a 105 litre fuel tank and having to have the spare wheel inside the car.

Wilson

A reasonable question PaulV