Dodgy Flange Piece Oooh Errrh

I got the halfshaft assembly all built up with the brake shoe assembly and drum last night. Gave the assembly a spin to ensure the brakes weren’t binding and noticed there was a severe amount of lateral run out on the drum face where the road wheel would sit.


I checked it with my DTI gauge and the run out measured in at well over 2mm at a radius of 55mm. I calculated that it would have equated to a 12mm run out at the wheel rim, obviously not acceptable!

Measuring the Lateral Run Out with a Dail Gauge

I suspected that the most likely thing wrong would be a bent outer halfshaft although it could also be a bent hub. To be honest it was getting late and I was frustrated and I thought damn it lets just get a complete 2nd hand halfshaft assembly to bolt back in the car. Sent off various emails and a post on the Club Triumph forum after midnight last night to see if anyone had any for sale. Lots of responses from the Forum and one from a Wins International who were listing 2nd Hand halfshaft assemblies on their web site. Plenty of responses but having thought about it I have a new bearing, a new rotoflex coupling a vertical link with good lower wishbone bushes and a long bolt that’s not seized so it would be daft to go over to a complete unknown quantity assembly when most of mine is good. I therefore decided to strip out the hub and outer halfshaft and inspect carefully to find which parts are damaged.

The most obvious culprit, the halfshaft actually seems to be true, but the hub certainly isn’t. I put the back face of the hub the a flat surface block of my Vice and measured the distance to the front of the hub flange around the circumference with my digital callipers. Sure enough the hub is distorted, the largest and smallest flange distance dimensions differ by 2.6mm around the circumference!

Measuring the Hub Flange Distortion with digital Calipers

New hub required then. Post put on the Club Triumph Forum to see if anyone has any good 2nd hand rotoflex hubs, I’ll probably ravel up to the Triumph Spares Show at Stoneleigh on Sunday to either pick one up from a member or try and find one. Failing that Canley Classics do have new ones but they are about 80 quid, ouch!

The other pain is that I’ve fitted my new outer wheel bearing and extended wheel studs to the bent hub so I’ll have to carefully try and recover these.