Picked up a Dura Ace 7600 front wheel June last year and figured it was about time I gave it a bit of overhaul. Read all the tips and tutorials online, got the cone wrenches and all that.
Managed to pull it all apart, degrease, rinse and repack everything with only a bit of difficulty. Inspected for pitting and other damage and it all seemed good. Thought I would be all good to go.
Problem is now it spins pretty rough - it was spinning fine before hand. Played around with the tension for AGES before getting it just tight enough to stop the axle from moving side to side so I think I have that squared away. Any tips? Better grease perhaps? Maybe there are some nooby mistakes I’ve unknowingly made?
The adjustment should be slightly loose before the skewer is tightened. If the adjustment is just right off the bike, clamping the skewer down can cause the bearings to bind.
What Snowflake said, but some other possibles are:
One of the metal dust covers on the cones might not seated 100% so its catching. Also if it has a O/S axle one of the bearings maybe have fallen into hub shell.
Edit: oh I googled and it’s a track hub and it doesn’t seem to have dust covers or an over sized axle.
Not enough grease*? Too much? Residual degreaser contamination? Some grit you didn’t see? Something not seated quite right? one ball too many in one side** ?
I’d just say fuggit, pull it down, clean everything thoroughly, repack and reassemble with care & see what happens.
(*an old campaigner once told me he would pack his hubs a little heavy and spin the excess out with a power drill. I did it once)
Did you put back in the old bearings? When I overhauled my hubs the dude at the bike shop said to never put in the old bearings* - mind you, my hubs were from the early 80’s.
So I took his advice and got some new bearings. I told him I didn’t know what size they were and the hubs were French and we all know what the French are like with ‘standard’ sizes, but he was adamant he new what size they were. He was wrong, had to take them back and change them.
Bearings do fail by fatigue, bearings are cheap: therefore replacing bearings when you have the chance is a good idea
but if they ran smooth prior to disassembly and all still look round they should run smooth again if put back together right
Worn bearings will loose their shine and fatigue failures result in “spalling” meaning the balls look like they are pitted or cracked in half or have little craters in them
Will pull it apart again and give everything a good clean once more. Pretty sure I got the ‘tightness’ right.
Might also pick up some new bearings then if they’re not too much. Anywhere in Aus where I can pick some up?
Looked this up - [Dura Ace 7600](Dura Ace 7600). Need to hunt down 22 3/16" ball bearings.
Too easy then. Are there choices for different gradings?
Edit - Had a quick search and it looks like Shimano and Campag usually use grade 25 but for a small price difference you can jump up to a grade 10 or 5. I assume for just a few dollars more it won’t hurt to get the best.
So pulled them apart again tonight, gave them a much more thorough clean and let them soak a bit in degreaser. And then when inspecting (under better light) noticed very tiny amount of pitting on the cones. A single pit on each cone. Surprising as they spun perfectly before and only been in a light rain once.
Damn… well checked the hub and thats fine (thankfully). Been hunting around Sydney and online and I seem to be only able to find either the low flange spare cones or just the rear hub cones.
Can’t seem to locate any spare cones for a 7600 front hub?!
So didn’t manage to find replacement cones… so just got some fresh bearings. Repacked it again. Adjusted it super carefully and they spin great now. Not as nice as before but damn close.
If they spun fine before the rebuild, you didn’t pry out the seals and the cones are slightly pitted, there’s a giod chance they were loose before the rebuild. Keep you eye out for replacement cones and buy a spare set. Or buy hubs that take cartridge bearings and forget the silly loose-ball nonsense…