If you suffer from drumming in a Trienkel check Marcus is not hiding in the back before blaming the engine mounts!
Yes Treinkels do have a somewhat direct line of communication between engine and driver. You either do not like it or embrace the connection and use it to drive the car correctly as if it is vibrating or juddering it is probably unhappy. I would suggest the BMW dumper truck, sorry Isetta, has a far lumpier engine, hence the need for independent mountings and complex drive. You pay for this in weight and handling so the Trienkel wins for me. I always fitted Heinkel mounts if available as no slots, less give better stability but more vibration. Trojan mounts, slots more give less stability, less vibration. I fitted the bottom at ten past eight with the top at ten to four, just before tiffen in fact. This prevented up and down or for and aft vibrating and opposed the mounts for any odd angle. Mind you if the mounts themselves are loose, as they are in quite a few cars, then you are wasting your time!
Scootacar driving. Like any machine it needs to be set up. No idea what the book says but I had mine progressively sprung so no bumping. The trouble is the springs are 50 years old and many are noshed by restoration in sand blasters, heating and other treatments before being refitted. The handling is far better than the shape would suggest as all the weight is lowdown. Like the Type 70 Invalid carrage. The Villiers can really perform in this car as it does not overheat and has a chassis to explore handling governed by small wheels that will let go before the thing falls over and the novel ability of being able to stop. The same cannot be said for the Frisky Trike I drove. It was not stable in a straight line, noisy and tripped itself up on hard cornering. It did stop though. Bonds, bless them, were not meant to be driven by me and they are not really speed machines. Not that Nick Price's G was a sluggard. I have a prob with non fan cooled engines in cars as they get so hot in traffic and on long climbs. On Saintbury the Bonds on the run out from Dorsington all seized within 100 yards of each other. Mega fag break. Berkeleys are not famed for their hillclimbing ability. Yes a Scootacar is noisy but what else do you want to listen to? A radio, a moaning passinger? It is part of what the car is and I have not noticed many Scootacar owners making great efforts to quieten the things down. Quite a few make it worse by having a bodge exhaust. I except, though, that my judgement is always biased toward a car than gets a move on. I am not there to offer entrainment to other people but to have a full driving experience of five senses and a bit of excitement.
Fortunately we all like different classic cars otherwise life would be extremely boring, like modern cars are!