late night slightly technical wheelbuild question

Last few wheels I’ve made have been for cross and roadbikes and I’ve done them 3X drive side, 2X none drive side (to even up the spoke tension)

Is there any reason why I shouldn’t do this on disc wheels for MTB?

(also, PSA £212 for rear King ISO disc at Stif)
(but I still bought Hope)

Yes

Disc wheels put extra tension through the spokes. I would happily run a non disc wheel radial on the non drive side, 2 cross is fine, but when you put disc brakes into the equation, you get a lot more tension going through the spokes than you do in a non disc wheel.

Running 2X instead of 3X is worth approximately the square root of bugger all in terms of a weight loss anyway, you’re talking what, 5-6mm shorter spokes. You might save the weight equivalent of 1 spoke over the whole wheel by using 2X on the disc side, if you are VERY lucky!

It is definitely not worth the bother.

Why do you think evening up the spoke tension between sides is important? 3x all the way for me.

Having had Hope Pro2’s since last year I definately wish I had gone for the King if they are at that sort of price. Not been that impressed with my Pro2, it’s certainly not a good replacement for the old XC hubs.

As far as the spokes go, I can’t see any reason why not to go for 3x both sides.

That’s around £40 cheaper than Aspire, has anyone tried to order one yet?

thanks all
I believe the theory behind 2X, 3X wheels is that even tension between the sides makes a wheel less prone to going out of true. I suppose this is less relevant on a disc wheel that is not dished as much as a non-disc (???).
I’m not bothered about the weight saving (although my reasons are probably equally petty – but why build your own wheels anyway if you’re not going to be perfectionist?)

Why and how do you come to the conclusion that you will have better spoke tension with less crossings ? Surely if the wheel is correctly built and dished you will achieve the maximum spoke tension relative to the offset in the hub ,ie the drive side on a nine spoke rear having approximately three times less than the non drive side ?

Sorry, you’ve lost me a bit there (on the relative to offset bit)(I’m not an engineer – I’m a mycologist with too much time to look at the internet)

I mean that with 2X non-drive, 3X drive you get less difference in spoke length between sides and less difference in tension, as measured with a tensometer.

Thing is, if I were to insist on running a 2x one side 3x the other I’d rather run 3X on the disc side. You’ll exert more force braking than you will trying to accelerate.

I’d be more likely to run radial drive side and 3 or 4X disc side though. cos it’s just as worthwhile….

I’ve run radial non disc side before, but only with normal DT double butted spokes as revolutions stretch too much and the non disc side came loose. Worked fine.

3X both sides with Dt revs or sapim cx rays is the best way to save weight and have wheels that will last a bit.

It really depends upon what you want to use them for. I have an XC bike that I run DT revs with, tried on my 140mm FS but ended up breaking a couple of the spokes as I tended to push the wheels a little too much. so normal DT’s on the back for me for that setup. Ran absolutely fine on the front though.