Twelve years with this bearing set up no crank end float no timing gear wear revs to 7500 lots of h/climbs sprints track days flat out on banking
at Rockingham, lots of laps of Goodwood, Silverstone, Mallory, Brands, quite a few other engines have been racing for 8, 10 years with this
setup so I think it works make your own choice this is just my experience. Photo not my engine just a build example.
Terry.
28-02-2019, 08:52 PM (This post was last modified: 28-02-2019, 08:55 PM by Bob Culver.)
The days of frugality and experiment are largely over but, esp with modern ratings, and cf motor bike engines, I cannot see why two relatively inexpensive ordinary ball races cannot be used at the front. To avoid the expense of modified width bearings on later engines a single bearing and spacer rings may even suffice.
Many cars had direct timing gears although many later not metallic. (Model A, Morris Oxford 1950, Holdens etc) with several thou crank end float. Many earlier makes would have been metal to metal. Other than possibly noise I doubt if a few thou end float matters.
Before o rings were common I used to reduce camshaft oil leaks by simply building up with solder.
I cannot see the benefit of fitting a single row deep groove ball bearing and a double row self aligning bearing on the front of an Austin Seven crankshaft.
The self aligning capability is negated by the ball bearing although the drsa bearing rolls a little more easily than say a roller bearing.
This doesn't mean it won't work - just as using two front ball bearings or two AC bearings mounted front to front or back to back will work, it is just that I cannot see any great benefit in fitting a double row self aligning bearing and a single row ball bearing on the front of an Austin Seven crankshaft from a bearing design perspective.