Just mad… that’s all.

unclebilly · unclebilly's Garage

I have been co-driving in endurance races in friends cars. Twice we have barely missed the podium (by a car length in the last race) because we had to replace a front hub on the car.

Miatas have a well documented front hub weakness. I addressed this by designing race hubs for miatas (similar but 1/2 the cost of the other guys who are doing this). I think my hubs are stronger than theirs, we both use the same SKF bearings. Mine are made from 4140 chrome moly and are beautifully CNC machined.

The first car to get these won its first race and everything seemed ok until they noticed bearing slop after the race.

When they installed the hubs, they only torqued them to 150 ft-lbs and didn’t stake the nut. The spindle nuts came loose (3/4 of a turn on the drivers side) and maybe 1/4 turn on the passenger side. They basically raced for part of the race with no preload. This could have been far worse. I had a family commitment so didn’t race with the team in that race.

Anyway, the bearings are screwed. They smell like welding, the outside races are all discoloured. I replaced $150 of bearings on my dime (I donated the first set of hubs to the car). I have 6 sets of hubs that are not spoken for yet, partially due to uncertainty about needing to replace the bearings after 3 races.

Anyway, we have 2 days of racing this weekend. After this, I’m hoping to unload the other 6 sets of hubs. I’m bringing a set with me to the race.