Type 13 - Front Wheel Bearing Spacers

Many are installing spacers in the front wheel hubs to keep the bearings properly spaced.  This enables the bearings to support the sideloads better.

I did not include spacers when I first built my Bugatti.  The time crunch to be ready for Huntsville was one reason, secondly, after watching Denny Graham’s post I thought I could not do a good job without the special tools he used.  Third, Kelly Wood told me they were not necessary and he didn’t use them himself. 

In taking my wheels on and off several times over the past year, I discovered my bearings were inward of the hub rim, and even crooked in one case.  So I decided it was time to add some even with the use of crude tools.  After all, this is a cyclekart and not a Formula 1 racecar.  

 

As Found

This picture shows the backside of one of my front hubs.  It is properly seated fully into position; however does not support any side load. 

Here are the steps I used, however crude.  But it worked to my satisfaction.

Bearing Extraction Large

Step 1 - Remove Bearings

Using the bearing puller I purchased when my TAV drive shaft failed, I was able to easily pull out each of the backside bearings.  I left the wheel front face bearings in place.

Flush front Large

Step 2 - Tap the Front Face Bearings Flush to the Outside

I took a pieve of flat metal and laid it on my softwood workbench.  Then with the hub face down on the table, I used a metal rod and a rubber hammer to gently force the face-side bearing to be perfectly flush with the hub face.

Cut Tubing Large

Step - 3 Measure & Cut Spacers

The spacers were fabricated from 3/4″ pipe pipe that I measured at 1.045 OD and 0.875″ ID.  Using my digital calipers the depth from the faceside bearing all the way to the back of the hub measured 2.213″.  The bearings are 0.352″ thick.  So by subtracting one from the other, I got 2.221 for my left wheel and 2.188 for the right.  I did not add 1 mm per my hand written note!  My bad!  That was probably an in important element in making sure the bearings were indeed providing the side load support, which was the entire point of these spacers. 

I just used a cheap abrasive chop saw to make the cuts.  Knowing they are not very precise, I intentionally made them a bit long.  Miraculously, after squaring and cleaning up the first spacer it was right on!  The second one took a fair amount of hand filing, But I got it there.

Flat bar press Large

Step 4 - Installed Spacer and Backside Bearing

Once the spacers were perfectly square and the edges cleaned up, I inserted them into the hubs and began reinstalling the backside bearings.  After slightly greasing the bearing with lithium grease, I positioned it into place and began to seat them using my trusty rubber hammer.  Once started, I then used a large flat steel bar, in this case an old bucking bar, across the face and tapped the bearing fully into place.

I was very pleased with the result; the bearings were perfectly flush now.  It took me under one hour and was the perfect little afternoon project in perfecting my Bugatti.