Why is the valve hole in my MAVIC rim off centre on the rear and on centre on the front?

[Mr 'P']

Anyone seen this? My lovely Mondraker Chaser R came with MAVIC eDEEMAX 30 UST rims with the valve holes drilled on centre on the front rim and considerably off centre on the rear. I asked the retailer (Biketart) why and they could not understand it so referred me to MAVIC's UK distributor Chicken Cycle Kit who have been unable to answer. Chicken Cycle Kit asked me to send both wheels to them but after several hours trying to package em and, after asking Chicken Cycle Kit if they had boxes available which they said they didn't and would charge me for shipping them to me if they did I've just given up. It is my opinion that the rear rim has been drilled incorrectly by MAVIC during manufacture but their UK distributor seems uninterested in getting to the bottom of this likely manufacturing quality matter.

 

[irie]

Just a pure guess but perhaps it's off centre on the rear to take a speed sensor magnet when on another bike model?

 

[Husky430]

Poor workmanship?

 

[mintyjim]

They’re offset on my deemax’s too, it’s not an uncommon design feature, my Shimano XT wheelet are also offset.
My e-deemax’s came with the correct offset spacer that sits on top of rim before you screw down the threaded nut you see in your first picture.
I’m sure the Mavic website details this.

 

[mintyjim]

https://technicalmanual.mavic.com/tech-mavic/technical_manual/data/docs/themes/2_32.pdf

Look at the bottom of page 5. With your bike (I also have a Chaser) you should have received a Mavic bag of spokes and valve spares).

I’m very surprised Biketart and/or Chicken didn’t know this!

 

[Mr 'P']

https://technicalmanual.mavic.com/tech-mavic/technical_manual/data/docs/themes/2_32.pdf

Look at the bottom of page 5. With your bike (I also have a Chaser) you should have received a Mavic bag of spokes and valve spares).

I’m very surprised Biketart and/or Chicken didn’t know this!

Many thanks for sharing your experience MintyJim. Yes Biketrart and Chicken referred to that data sheet, (which I'd already taken from MAVIC's website) which pointed this out - I also had the welcome bags of useful bits supplied with the Mondraker see attached photos. You can see that what was supplied was not as the MAVIC's data sheet (not UST type valves but with the tapered spacer) which made the confusion over why the rims are different even more. The front would not need the tapered spacer and the rear would and the two bags have differing part numbers - strange. WHY is the front different from the rear?

 

[Mr 'P']

Poor workmanship?

Not sure Huskey430, that's why I'm asking if anyone has seen this before and why the rims might be different. To me it makes no sense except for a manufacturing error. Thanks for your input.

 

[Astro66]

It is my opinion that the rear rim has been drilled incorrectly by MAVIC during manufacture but their UK distributor seems uninterested in getting to the bottom of this likely manufacturing quality matter.

The rear rim is offset to one side to centre the hub, as the driveside of the hub sticks out further. On some wheels this is done by using different length spokes on a symmetrical rim. And in your case it's done by using an asymmetrical rim. So the valve hole looks offset.

The front hub is far more symmetrical, so doesn't require an offset rim. You can centre the hub, by adjusting the spoke nipples to change spoke length.

Centring the hub in your rim is called "Cupping", because you are changing the cup shape the spokes make, by tightening and loosening them. The longer the spokes. The more "Cup" shape. The shorter the spoke. The less "Cup" shape. There are lots of videos if you wish to learn more.