dedicated 20mm thru axle hubs (Dishless?)

[tnankie]

Greetings all,

DISCLAIMER: This post is about a minor personal niggle that probably makes a gnats dick of a difference, but please indulge me.

I am looking for a front hub to build a new lightish wheel set on. Originally I was looking at a set of DT EX1750’s to give you an idea of what I am aiming for.

Now for my problem. I want a 20mm axle hub. 20mm hubs are a bit wider that QR hubs, I believe its 110mm vs. 100mm. Now an non-disc QR hub is 100mm and has no dish in the spokes, a disc QR is dished to make room for the disc mount. Now I thought the reason for going to 110mm on the thru axle was to go back to a dishless front wheel, can anyone confirm or deny this?

Assuming this is correct, I shall move one. Some 20mm hubs are convertible, I am thinking of Hope right now but I think there are others. These convertible hubs are obviously going to be dished. The problem is that I was told that a lot of non convertible 20mm hubs actually use the same hub body as their QR brethren and hence also build into a dished wheel.

Does anyone know of a 20mm hub that will build into a dishless wheel? I am trying to find some info on Hadley and Ringle, but am finding it quite difficult. Or can someone link me a document of the 20mm standard?

[chu]

ok do you think that you might be able to post up a picture of the dish in the hubs...i was just wondering what it is...thanks

[frostbite]

OK, i just went and had a look at my Hope Pro II front for you and there is a definite dish to the wheel. As you said, the pro2s are convertible to QR (or so I've heard.. never had to research it personally)

Also - from what I can see if there wasnt any dish, despite the wider drop out spacing, the wheel would be off centre as aligned to the 'centre line' of the bike. IE The rim would have to sit a little to the right to make room for the disk mount. The reason that non disk QR doesnt need dish is because it doesnt have a disk mount so therefore the hub body can be symmetrical. The only way I can see making a disk hub without dish is to have the flanges which the spokes feed through on the hub equally spaced from the centre line, which means you would need to move the right side in towards the centre of the hub to make up for the disk mount.

Let me know if that doesnt make sense.

[AngoXC]

I figured the extra 10mm was to increase stiffness as you had a wider platform to play on but figured that it was dished accordingly to accomidate the disc brake interface. In short, sorry, I cant answer your question BUT if any forum could, RideMonkey should. They have a fairly large discussion going on the Hope Pro II hub, might reveal something. Good luck!

frostbite, you could also achieve zero dish if say you had spoke flanges that were very close togeter so that for the room the disc interface took up, it had that equal amount on the other side (symmetrical as you say)...sure I heard of it once but I honestly cant remember...

[red_dog]

As far as I know Hadley and the late Aireal (RIP) hubs are A symmetrical or 'even tension' I think its called

[tnankie]

Also - from what I can see if there wasnt any dish, despite the wider drop out spacing, the wheel would be off centre as aligned to the 'centre line' of the bike. IE The rim would have to sit a little to the right to make room for the disk mount. The reason that non disk QR doesnt need dish is because it doesnt have a disk mount so therefore the hub body can be symmetrical. The only way I can see making a disk hub without dish is to have the flanges which the spokes feed through on the hub equally spaced from the centre line, which means you would need to move the right side in towards the centre of the hub to make up for the disk mount.

Let me know if that doesnt make sense.

yeah I think you might be right, although if the fork was off center (left leg set 10 mm wider than the right) then you might be able to achieve the same effect. Actually I think you can also get the same effect by making the disc side flange higher. This raises the point at which the spokes start and does in a small way make them less perpendicular to the axle...might need a picture....so if you made the right side as low as possible and raised the left you might end up with spokes that were dishless, though you'd still have shorter spokes on the disc side.

It also seems after some time looking at the Chris King specs that my (bike shop given) information was incorrect. Their 20mm hub does have wider flanges than their standard disc hub.

So it might be time to go back and have another look at the DT oversize 240's ... if they make use of the extra width then its probably as good as it will get.

Thanks everyone.

As far as I know Hadley and the late Aireal (RIP) hubs are A symmetrical or 'even tension' I think its called
I think thats their 150mm rear hubs. I remember reading an article about how most 150mm rear hubs are still dished despite the standard being introduce to avoid it and that Hadley were one of the few that made a dishless rear wheel.

[DownhillerDeano]

ok do you think that you might be able to post up a picture of the dish in the hubs...i was just wondering what it is...thanks


AFAIK, dishing of a wheel is how centralised the rim is compared to the hub. Some frames require the wheels to be dished more to one side or some frames compensate that the right hand side needs to be further off center so the hub is smack bang dead center and in line with the front hub/rim.

[frostbite]

yeah I think you might be right, although if the fork was off center (left leg set 10 mm wider than the right) then you might be able to achieve the same effect. Actually I think you can also get the same effect by making the disc side flange higher. This raises the point at which the spokes start and does in a small way make them less perpendicular to the axle...might need a picture....so if you made the right side as low as possible and raised the left you might end up with spokes that were dishless, though you'd still have shorter spokes on the disc side.


Yeah it occurred to me last night that I used to have a 20mm front hub which did have the higher disc side flange. It never occurred to me at the time what it was for.

Is there a significant increase in strength if you get rid of the dish in the wheel?

[thecat]

As far as I know... the late Aireal (RIP) hubs are A symmetrical

Correct, and nice hubs they are too if you can get. There may be few sitting around on selves out there somewhere.

[tnankie]

Yeah it occurred to me last night that I used to have a 20mm front hub which did have the higher disc side flange. It never occurred to me at the time what it was for.

Is there a significant increase in strength if you get rid of the dish in the wheel?

I'm not sure, TBH the front wheel generally isn't dished that much SO I don't think its a big problem. More of an interesting technical exercise, and a gripe that we have the extra 10mm and generally dont do anything with it.

Oh and it occured to me this morning that you wouldn't even need to have the fork legs being unsymetrical about the center line, just off set the disc side dropout.

[Cooch]

I'm pretty sure with all the Hope Pro II hubs (front 20mm) I've laced up into wheels, the spoke lengths have been identical for "drive" and "non-drive" sides. That is, the slight difference in hub center to flanges washes away when lacing up the wheel...