Having spent most of my spare time this month either working on the house or stripping the Bantam engine, Father's Day bought the first chance to take a look at all the bits I had collected for the Ariel and to try some of them out.
An eBay auction brought a pair of handlebars purporting to have been taken from a plunger NH - these should be correct for the Square Four if indeed they did come from a plunger NH, which I am beginning to doubt - they look a bit high to me:
Whatever they are from, they look a lot better than the flat 'Norton Straights' that were previously fitted, snaffled from the box of bits that came with the MZ.
The next job was driven, as I have said previously, by a suspicion that the gearbox was wrong. In an earlier post I reported that a G106J51 gearbox comes from a 1951 KH, VH, KG & one or two others. There was a suspicion that the main shaft was different and I was trying to get the transmission together to check the chain alignment, and I though I had achieved that. Secondly, a Burman BA gearbox purporting to be a 1951 Square Four gearbox, labelled G107K51 (the correct code) appeared on eBay - but it was quite obviously not a Square Four gearbox casing - or even an Ariel casing - however it was attractive (or would have been at the right price) because the kickstart housing carried the correct number and the clutch cable abutment was intact - mine is broken.
I'd also checked through the engine mounting plates & studs, and started to talk to Acme Stainless about replacements, so it was time to get the gearbox in it's plates. The result was not too happy.
See the arrows? In this picture, the bottom lug of the box is in the correct location in the frame. The left hand engine plate, on the right in the picture, is fitted correctly to the frame lugs, but there is a 1/8" gap between it and the gearbox. This gap is repeated on the other side, where it appears at the frame. This is because the casing on a Square Four box is different to that for the singles & twins, because for some reason the gearbox is shifted to the left. Research reveals that the mainshaft is also different.
So, pleas are out to DragAnFly, the AOMCC members, and to the nice lady from Essex to try and locate the correct box!