Traction Owner’s Club › Forums › Technical › Engine › Conrod shell sizes › Reply To: Conrod shell sizes
From CTA Service Bulletin:
Crankshaft
Main bearing: 50.00 mm std.
Con Rod Crank Pin 47.990-48.000 mm
Main bearing Radial Play: 0.04-0.08 mm
Con Rod Radial Play: 0.10-0.15 mm
Measure the axial play from the rear bearing at transmission chain.
So yes Jonathan 48/50 mm is standard.
If you do need the crank reground then look for someone with an old ‘Prince’ grinder as it can do the journals individually, modern machines can only do all the same size apparently.
Where it matters is that being done individually the minimum (within tolerance) can be taken from each one leaving more ‘meat’ for potential future renovations.
Good luck with the search.
BTW Traction Universelle 50th Rally is at Magny-Cour next week (10th-12th) so you may be able to pick up some parts there as there will be a jumble and some traders on site. (I have a list of things to look for 🙂 )
