General Disc Radness (formerly disc wheel valuation thread)

ps. YOLO

I reckon Scilly is correct. The composite side of the disc has broken where it's sandwiched by the internal/external parts of the hub flange.
You shouldn't be able to rotate this without removing the three flat-head screws of the outer flange plate.
Inside of the hub might look a bit like this:
https://www.flickr.com/photos/cronobikes/5513058996/in/album-72157612232975593/

ooh okay that picture is helpful. Even if it is broken though, I think the fix I've done will prevent it from moving. I bought it for a reasonable price considering fluidisk prices so I can live with it

So the flange with 3 screws rotated? or just inside threaded part?

just the inside threaded bit

So he was wrong :D imo just screw it back in and youre good to go and pretty safe for an old russian disk :D

About is spinning for a reason? I think I'm going to try and sneak my phone camera into the valve hole and see what the hub looks like

I think both lukas and scilli missunderstood that flange with flat bolts rotates not only the inner part or maybe im just lost again :D

Ah yep, I misunderstood which bit rotated. The flange must rotate around the threaded hub shell to tension/dish each half of the disc. Loctite to sort it?

so is it actually meant to move? At the moment it isn't moving anywhere as I've clamped it on both sides with cogs

i don't know, but I don't think it's meant to move. If it's like the above linked photo inside, it appears the only way to prevent the hub from rotating inside the flange thread is using glue. the threads were probably wound onto the hub on during manufacture, with a healthy coat of glue, then placed in a jig to set before laminating/glueing up the kevlar sheets that make the side?

Like you say, though, as long as the hub can't rotate inside the flange, it should be fine.
Edit: to my eye, in the image above, the visible hub threads are coated in some kind of glue/resin, which seems to be the only thing preventing the hub spinning.

Just to confirm the threaded 'rod' is the only thing that is moving? The flanges with the bolts do not?

The same thing happened to me with my fluidisk, I went to remove the cog and it moved the threaded 'rod' so I dismantled the axle, stuck a conespanner in the notches and u done the cog like normal. This held the 'rod' in place. I then had to turn the 'rod' with the cone spanner to re align the kevlar wheel back to the centre ever so slightly. The cog chainline was out by a couple mm I think. I asume that what has been said about the tension is also true but as long as both sides of the 'rod' turn at the same time tension shouldn't be affected?

yes, only the threaded section is moving exactly how you've described it. I was able to tighten the cogs by using the force of the cog on the other side pushing up against the flange, and basically just repeating it on both sides until both sides were fully on. I will note that it required a lot of force to get the cogs on towards the end. I definitely wasn't stripping and threads but it was a right bastard.

How did you know where the centre is? on mine the size of the threaded section on both sides isn't equal. I've just kind of put it back to where it roughly was before.

Fitting the wheel in the dropouts of a frame you know is true to centre. Also check chainline. I don't think mine is centred either so I just gauged it by the chainline and position in the dropouts an got them as central as possible

Anybody looking to get rid of a track disc? PM me

US based Mavic Challenger come up on eBay at a bit more reasonable price!

http://m.ebay.com/itm/222146244841

Are all the bearings the same in all HED discs? What measurements etc do you/I need to know to order the right bearings?

What Model do you have?

If they're cartridge bearings, there will be a code on them.

If they're loose: http://www.parktool.com/product/spoke-bearing-and-cotter-gauge-sbc-1

I have some spare (new) bearings for an older Hed disc you can have for a few £. FAG 6001 2RS

This is my problem - someone's removed the old cartridges...

Show us a picture of the disc/hub and someone might be able to give you an educated guess at which bearing. Otherwise, you may need to buy some vernier calipers.

mumble

I wondered if there was a general answer (eg: if HED had always used the same size bearings). This particular one takes 6001 bearings
I'm assuming it's an older model

@Lukas - Yeah, I used the calipers at work

Anyone got a cheap/ratty track disc going or knows where I can get one from? £200ish or lower