MB - Snapped crank repair


A good customer called today with this casing. Ouch! An AF crankshafts con rod had snapped and wrecked the casing!

My first question was 'is this your new Race-Tour engine'? It wasn't.

He also brought in one of our MB super thin pistons, in fact it's the thinest version of all our pistons, of course it had cracked but not all the way through. Wow, how strong are our pistons? It totally saved the cylinder which was a cast iron version and had no damage. We've seen a PM rod snap in the same place on an RB and again the piston didn't shatter! When we say a forged piston is stronger this is the proof, you don't get this with cast pistons, usually the cylinder is also destroyed.

Unfortunately the casing didn't hold. On first inspection it looked a simple job to repair. But as I started to prep it for welding I was chasing cracks all over. It's a typical Indian 200 the little noggins in the casing were all cracked one had already disappeared so it was a case of follow the cracks, grind them out, weld up the hole and make it look good.

And whilst he was there, he dropped his other bike the Race-Tour 225 with MB Clubman and 28mm Dellorto was pulling 80mph on the rally last week and was well pleased!












































Mark Broadhurst 8.8.2013