Tune straight 2015/16 lacing?

[qwpy]

Hello there.

I am hoping to lace up a tune rear prince QR 2015 (32 hole)the new 'unusual' looking version.

(picture below)



hope to lace with:
mavic xc-717 disc rim 26 inch (EDIT*i have just been told by mavic. (ERD) = 538mm (26 inch,mtb/mavic)
sapim cx-ray spokes (but not sure what lengths yet : ?)

I cant seem to find a picture of one of these hubs laced up. The hub is rather strange looking.
the pdf states:
“ The hub is constructed for radial lacing. The hub therefore must be laced radial on both sides. Cross lacing
is not allowed.”

As you can see in the picture above, the spokes do not connect 90 degrees straight up from the hub, they are set at an angl, yet apparently do not cross, if radial, perhaps? i am not an expert.

tune pdf.
“
PRINCE STRAIGHT:
The highest permitted spoke tension is 1200 N.
Pitch circle diameter Ø 47,0 mm / 57,0 mm
Spoke hole diameter Ø 2,4 mm
Distance hub flange to wheel center
line (l / r)
32,0 mm / 19,4 mm (QR5 / Maxle)
31,7 mm / 1”

sapim have a calculator. ( not sure if this is the best to use?)
http://www.sapim.be/spoke-calculator

below are measurements I have required for the calculator, so far.....

1.Total length of the hub: 135mm ( from where hub meets frame both sides/ end cap edge)
2.Non-gear side: 32.5mm? (hand measured from between the two spoke holes to where hub meets frame)
3.Gear side: 48mm? (hand measured from between the two spoke holes to where hub meets frame)

4.Hub diameter non-gear side: 47mm (from pdf)
5.Hub diameter gear side: 57mm (from pdf)

6.Internal diameter of the rim: 541.5 mm? < Likely wrong, this is the ERD (mavic customer service do not know IRD) I have yet to receive my rim to hand measure. I hoped to buy it with the spokes.

7.Rim thickness: 2mm ?? ( not known either by customer service. so I put 2mm) : /

8.Number of spokes in the wheel: 32
9.Number of crossings gear side: 0 (I presume, as radial)
10.Number of crossings non-gear side: 0 (I presume, as radial)


My results via the sapim spoke calculator.

Spoke length non-gear side:251mm
Spoke length gear side: 245mm

These seem pretty fair. What do you guys think? maybe i should buy 4 spokes first, to try this out?

I am wondering if anyone here has laced one of these up? Or can offer a bit of support
with calculating the lengths of the spokes?

Thanks : )

[qwpy]

I tried the dtswiss calculator instead. most of the values where on the pdfs already.

recommended spokes result was higher = 268mm + 266mm

pic below. i did not have the offset value for the spoke holes..hopefully this is meant to be zero on this hub ?

(EDIT * effective rim diameter of a mavic xc717 2016 = (ERD) = 538mm. for 26 inch,mtb )

[qwpy]

hello

i bought a rear Tune hub, called 'Prince straight' late 2015 version. ( uses straight pull spokes)

the pdf states regards Lacing:

"The hub is constructed for radial lacing. The hub therefore must be laced radial on both sides. Cross lacing is not allowed."

I just found an image of this hub laced ...the one on the right is the rear Prince.. ( pic below)

it does not look to me to be a radial lacing pattern? Maybe i am wrong? I wonder do any experts here know how many cross intersections there are here? Is it radial?

thanks : )

[eric]

Rear or disc brake hubs can't be radial laced on both sides. Just one. Something has to transmit the brake or drive torque from/to the rim.

[qwpy]

Thanks Eric.

So it seems the info on the PDF Tune sent me, is wrong for this hub.

I shall have to contact Tune again.

[ChrizZZz]

PRINCE = Front hub = right site radial

PRINCESS = Rear Hub = normal

[SportingGoods]

just to add to ChrizZZz's input: the crossed sides are 3-cross on this picture.

Everyone's free to do what they want, but I don't see the point of radial. It's OK for front wheel road bike but it offers no technical benefit on a MTB. Actually, I don't see the point of straightpull either (except for a full radial road front wheel). It makes the hub more complex, heavier. Regular spokes are just fine as long as the wheel is well build.

[Frankie - B]

Merged the two topics.

[UpFromOne]

new Princess front hub is as pictured. radial on non-disc side only. like Extralite.

recall that Tune is german company and looses in translation to english. no worries, hub can only be laced one way.

[qwpy]

i think you are right.

However, It states "radial both sides" in the german pdf also.

I'm sure Tune will respond. Hopefully tell me the spoke lengths.
I have just been told by mavic the xc717 disc rim has an (ERD) = 538mm

peace

[SportingGoods]

Don't wait for anyone to tell you the spoke length!

The only way to proceed is to buy the hub, the rim and measure yourself. Hubs measurements are usually accurate (because it is simple), but rims... there is multiple ways to measure ERD. I would not trust anything else but my measurement as a 1-2 mm difference can happen and cause problem.

It's a pain but you have to order your spokes after receiving hubs and rims. Don't try to save money and time or you have 50% chance to loose.

EDIT: and there is no doubt about this rear hub lacing. A rear disc hub CANNOT be laced radial (any side). It would damage the wheel when braking as well as when pedaling. It's not about design, it just can't be.