Just a shout out for my very good friends at Brands Hatch Morgan. Len, BHM's three wheeler specialist technician, has converted one of their belt drive Super Three demonstrators from the original belt drive to chain drive and the improvement is astonishing. No more banshee wail under load, it really is like chalk and cheese and makes the Super Three a joy to drive, rather than the chore that it was before. Apparently the chain drive is now a standard factory fitting for Super Threes, with belt an option for die hards. Len told me that in order to quieten the old belt drive, the belt had to be tightened so much that it was causing premature were on the drive and wheel bearings.
I'm fortunate enough to have driven this car before and after the modification and can thoroughly recommend interested Super Three owners to contact BHM and have a drive in the modified car. At the moment BHM also have a Super Three with belt drive by way of comparison. I don't know how much it would cost to change, but Len told me it took him about 3 hours.
My only connection with BHM is that of a very satisfied customer of more than 20 years. I am posting this with BHM's permission, they're too nice to blow their own trumpets!
Interesting Alastair. Phil Bleazey pioneered a chain drive conversion for his M3W and whilst it was successful in its own right, I got the impression it wasn't the improvement over the factory belt drive he expected.
Interesting video here on back to back dyno test of both drive mediums on same motorbike.
Not to mention belt having up to four times weight reduction, four times greater psi tensile strength, little or no lube and stretch maintenance, less snatch etc. Only let down is belt less tolerant of suspension articulation when front sprocket and swing arm pivot not concentric, leading to dynamic drive length variations.
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
Don't understand this love of chains vs a belt. A belt is much more tolerant of all the road dirt that collects around the back of our cars .... chains wear out ... with the steel rather than aluminium spocket, we have a reliable low maintenance solution. The only possible benefit is that one can take the chain out to change it without dismantling the rear end ... but chains need changing more often anyway! Besides the belt on our M3W, we love the belts on our eBikes that are far less hassle than a chain with no obvious wear after 10,000+km.
Len told me that in order to quieten the old belt drive, the belt had to be tightened so much that it was causing premature were on the drive and wheel bearings.
For the M3W overtightening the drive belt will often lead to it squealing. The factory spec tension is too high and a rule of thumb is to set the belt so you can twist the lower run by 45 - 90 degrees. Do this and it'll be quiet and the bevel box bearings will last.
My view is the Super3 belt is also set too tight and I know of a couple of owners who have slackened them off to a similar tension to the M3W and the belt noise disappeared.
If your Super3 is making a noise try slackening the belt to see if it cures it. If not you can always tighten it again.
I know chains have been improved substantially over the last 50 years but I ran a Vincent Shadow and Steib sidecar outfit for 30 years (between the mid sixties and the mid nineties) and with hard driving and sometimes pulling a camping trailer, although the engine was only rated at 55BHP, after about 5000 miles, even with regular miantenance, the rear chain looked like a bit of knotted string and had to be replaced.
