Replacing Novatec Front Hub Bearings
For some time I'd been aware that my front hub bearings felt a little rough. I don't know anything about bearings. I knew that my hubs have cartridge bearings but that was the full extent of my knowledge, I had no idea what size bearings they were or how I should set about acquiring replacements. Then, after a very wet ride, the water round my front hub was rust coloured. It was time to learn about bearings!
My immediate thought was to take the wheel to my LBS and let them sort it out. They replaced the bearings in my rear hub last year but they charged me £40 for the privilege which seemed an awful lot of money. I do like to do things on my bike myself so I decided to give it a try. As I said I had no idea what bearings I needed or where I could get them from so decided the easiest course of action would be to phone Harry Rowland who built my wheels and ask him. Harry is a mine of information and very helpful. He told me the number of the bearings that I needed (6092RS) and that they were very common bearings available from any bearing supplier. When I told him that I was not at all sure that there were any bearing suppliers on the Isle of Wight he kindly offered to post me what I needed. Excellent! Fitting them, he told me, was 'a piece of cake', 'a five minute job'. It sounded promising but I wasn't convinced that his five minutes wouldn't be more like an hour or two!
The bearings duly arrived and so armed with 'Zinn and the Art of Roadbike Maintenance', a 2mm allen key and a large rubber mallet I set to work. I removed the wheel then closed the door on Roberta so that she couldn't see as I took a mallet to her vital parts! After removing the quick release skewer the next task was to remove a tiny grub screw with a 2mm allen key.
Now for the mallet! Tap the axle gently to loosen the end cap on the opposite side. According to a thread on the internet removing the cap could be quite tricky but once loosened it twisted off quite easily as if it was being unscrewed.That just left the bearings. A few more whacks with the mallet on the end of the axle and it shot out with the bearings attached. I replaced the axle and hit it again to dislodge the bearings from the other side. This was going better than I'd dared hope!
According to Zinn
'Reinstalling the bearings in most of today's cartridge-bearing hubs is relatively easy: simply press the bearings with your hand, or use the shoulder on the axle as a punch to press the bearings into place.
.......However, with some cartridge-bearing hubs it isn't so easy. The tolerance between the hub cups and the outer surface of the bearing is so tight that these bearings must be pressed in or pounded in with a hammer.'
My hubs are firmly in the latter category! To avoid wrecking the new bearings I had to place the old ones on top and then hit them with the mallet. This was easier said then done. I couldn't hold them in place without hitting my fingers and so every time I hit them they fell off and I couldn't seem to get them straight. Eventually Dennis came in and pointed out that unless I held the wheel straight I would never be able to hammer them in straight. Why hadn't I thought of that! With Dennis holding the wheel straight from the other side they went in relatively easily. With one set of bearings and the axle fitted I now had another problem, how to hammer the bearings in without hitting the end of the axle. I used both sets of old bearings on top of the new ones and, to my surprise, with the wheel held straight they hammered in quite easily. Job done!
When I looked at the old bearings one side was fine but the other set were very rough. I prised off the rubber seal and found that they were really rusty and full of gunge. My front wheel now runs beautifully smoothly and bearings are no longer such a mystery to me.