Mountain Bike Reviews Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
394 Posts
Discussion Starter · #1 ·
I finished my first wheelbuild.
front XT disc
DT 2.0/1.8/2.0
Mav¡c 36 hole 317s

it is now true and dished and round.

I figured spoke tension would be more important on rotor side and I concentrated on the disc brake side of the wheel as it gets all that brake torque. they were all between 90-110 Kgf. Sat back patted myself on the back and then decided to check the non-rotor side. the tension on those spokes were 60-70 Kgf range. is that enough? seems a little low. if I try to increase tension on non-rotor side, I will have to crank up the tension on the rotor side to keep dish OK, and I don't really want to go over 110-120 Kgf (just cause I read Mav¡cs should be between 90-120 Kgf).

Thanks.

PS: thinking into the future, should the rear spokes drive side and rotor side be nearly the same? or should drive side still be a little more as in non disc wheels?
 

·
Premium Member
Joined
·
48,238 Posts
minh said:
I finished my first wheelbuild.
front XT disc
DT 2.0/1.8/2.0
Mav¡c 36 hole 317s

it is now true and dished and round.

I figured spoke tension would be more important on rotor side and I concentrated on the disc brake side of the wheel as it gets all that brake torque. they were all between 90-110 Kgf. Sat back patted myself on the back and then decided to check the non-rotor side. the tension on those spokes were 60-70 Kgf range. is that enough? seems a little low. if I try to increase tension on non-rotor side, I will have to crank up the tension on the rotor side to keep dish OK, and I don't really want to go over 110-120 Kgf (just cause I read Mav¡cs should be between 90-120 Kgf).

Thanks.

PS: thinking into the future, should the rear spokes drive side and rotor side be nearly the same? or should drive side still be a little more as in non disc wheels?
My wheels with the same hub and same size spokes are nearly tension as yours. Works fine. The disc side on the front wheel are always going to be higher tension than the non-disc.
 

·
Registered
Joined
·
8 Posts
minh said:
1) I figured spoke tension would be more important on rotor side and I concentrated on the disc brake side of the wheel
2) as it gets all that brake torque.
1) Tension is equally important on both sides IMO. I built my wheels with more tension on the disc side simply because it needed to be like that to pull the dish right - its not something that can be done by figures and maths - thats why handbuild wheels are far superior to machine built wheels. I always start on the disc side thought, and let it lead the non-disc.

2) The disc side doesnt get all the torque, the torque is shared reasonably equally to both sides, but only the spokes in one direction from the hub. If all the torque was concentrated on one side you would have the rim pulling over to one side during braking, which doesnt happen.

As for the spoke tensions - no idea, I build my wheels by ear, so I've no idea what tension is in them. All I can say is that just going by ear, and having a distictly less tensioned non-disc side not by choice, I've never yet buckled either rim, despite 5ft flat landings and gnarly roots from hell :)

James
 

·
Registered
Joined
·
87 Posts
The load and stress of braking will be taken by both side. The rotor side of the front hub will be tighter as you noted. The wheel should be fine as it is. You can try to tighten a bit more, but much more tension will get you over the 120 kgf.

In regards to the PS, it is typicaly the rim in all cases that limits wheel tension. The hub and spoke can take more stress then the rim. If you set the tension to the max, say 120 kgf in your case, then it is correct to say the drive side of the rear and the rotor side of the front will be about the same.
 
1 - 5 of 5 Posts
Top