Just had a new pair of 819 UST rims buit up, and noticed the 2013 rims are asymmetrical in profile which is a completely new design to my 2 year old previous 819 UST’s. Does anyone know if one particular side should be built in the direction of rotation or not please. The asymmetrical profile is quite noticeably different each side of the rim with the valve hole appearing off centre. I can’t find anything on the Mavic website to answer this.

Thanks

morning bump

Hi Pete!
Sure they haven’t just been drilled wrongly?
I must admit I’ve never heard of any asymmetric mavic rims until now. Sounds like witchcraft to me.

Mountain bike rims XM 819 Disc

The highest level of technology ever seen in a single rim : ISM, UST, Fore, Maxtal. This 19mm asymmetrical rim is the perfect partner riders looking for light and versatile rims. Available in 26/29.

Looks like they’ve started doing ISM aswell, bloody hell mavic finally updating their rims. Still a portly 450g tho, presumably you need to add 50g of fore nipple to that….?

Perhaps Mavic didn’t go on their 2 month summer holiday like usual!

I’d like to see an 819 in 650b.

Hey Paul! Great to hear from you – been a long time mate, hope all’s good with you?

Yeah, they’re quite funky the new 819’s and I think the 450g may be referring to the previous model, but who cares they are the lightest rims I’ve had on a bike! I pair them with the super light drag free Rampage UST tyres as well – fastest rolling tyre I’ve ever owned too! Ha – I like my stuff durable if I need less weight I’ll take a dump before a ride :0)

Just had a look at the new 821, also 450grams. I think thats wrong, shirley?

Mountain bike rims EN 821 Disc

The highest level of technology ever seen in a rim : ISM, UST, Fore, Maxtal. This 21mm asymmetrical rim is the perfect partner for riders looking for strong and versatil rims. Available in 26/29.
Weight : 450 gramshmm sounds familiar, so wonder what the real weights are (with fore nipples aswell)

My Stans Flow is 4 years old and starting to show cracks around the eyelets, Id be interested in the 821s and I always rated 819s before trying Stans.

Isn’t any assymetry (which pretty much everyone else has given up on) there to help with dishing (and so that dictates which way round you build them).

ISM is a bit of a joke on a rim this heavy (if not all rims).

ISM is a bit of a joke on a rim this heavy

the rim is silly strong (for it’s width) and also stupidly heavy*, what’s wrong with losing some of the lard? Make the 819 400g with the fore inserts and I’d have another. or if the 821 was <500g I’d be tempted.

My Stans Flow is 4 years old and starting to show cracks around the eyelets,

IIRC flows don’t have eyelets, possibly the reason you’re seeing cracks (mind you I had some mavic 517s that cracked around the eyelets)

My 719s cracked round the eyelets too, most cracked rims I’ve seen have been 721s doing the same. (my Flow cracked at the valve hole, just to be capricious)

I’m more than happy with the weight of my old 819’s so looking forward to these – I’ll feel like flying! ;0)

To get back to the op’s original point the face of the rim that the valve is closest to go’s to the non drive side.