Mavic Ksyrium SL's rolling slow

[Dsan]

Morning all,

 

Finally got a set of these after wanting them for a while and after 400km's, they really do roll pretty slow. Nothing is causing the brakes to drag, they run true and I can't see anything untoward with the bearings but they aren't exactly speedy.

My 23-year old Mavic's with campy hubs out perform these, and that's worrying.

 

Any other SL owners out there able to give any insight as to why they are this slow? I've seen some ceramic bearing upgrades that claim to sort the issue out, but not sure about how right that claim is.

 

thanks

[Bike Mob]

if you spin them manually when there is no load on the wheel do the spin? or is there major drag...

[Mongoose!]

Sold my Cosmic Carbons because of this. Spin nicely with no load, but when riding I lost speed at the down hill. (That after I replaced all bearing with new ones.)

[Dsan]

yah exactly the same thing here, free-wheeling down a steep hill, i'm getting 45kph max. strange.

[Dsan]

if you spin them manually when there is no load on the wheel do the spin? or is there major drag...

 

they do spin, as you'd expect them to. it's when you ride that you notice a difference. they just feel slower than any other wheel i've ridden with. almost like under load, there is something dragging

[onetrackmind]

they do spin, as you'd expect them to. it's when you ride that you notice a difference. they just feel slower than any other wheel i've ridden with. almost like under load, there is something dragging

Enter Mr Bornman, stage left...

[gummibear]

Sold my Cosmic Carbons because of this. Spin nicely with no load, but when riding I lost speed at the down hill. (That after I replaced all bearing with new ones.)

 

I have been riding Cosmics since the first alu ones many years back and never had that problem.For the first few hundred kays they are stiff and then loosen up and roll like a dream.

[Mongoose!]

I have been riding Cosmics since the first alu ones many years back and never had that problem.For the first few hundred kays they are stiff and then loosen up and roll like a dream.

 

mmmm, I think where the problem started was that I tried out other wheels as well. Dura Ace / Vualta / Zipp etc.

 

Then I realized my unfair disadvantage with the Cosmic's...

[Johan Bornman]

Enter Mr Bornman, stage left...

Why? Looking for some entertainment? I'm not biting today thank you.

[chris_w_65]

Is it not the wind resistance of your hair causing the drag?

[Dsan]

yes, that dutchman style mullet causes drag. I usually slick it back but the cherries prefer it out.

[eraser]

Is it not the wind resistance of your hair causing the drag?

 

Lol...can always turn to the Hubbers for a laugh...good one Chris!

[onetrackmind]

Why? Looking for some entertainment? I'm not biting today thank you.

I need to ask a direct question then:

 

Mr Bornman, is it possible for a layman to accurately detect a difference in performance like this?

 

If not, we can happily agree to agree, and leave it at that.

 

If so, my only likely theory is that the tightening of the skewer is compressing the bearings somewhat - which I would think unlikely with modern sealed-bearing units. Back in the old days, we would set cup-'n-cone bearings slightly loose, so they tightened up just perfick.

[Ghostface]

This is written in your instruction manual that you should have gotten with your wheels/bike. You should also have gotten the relevent tool (plastic looking wrench)

 

My link

 

Mavic QRM+ Adjustment Explained

We here at Dragons Sports are committed to keeping you, the customer, informed and updated with news and features of our products. Today we'll be highlighting the Mavic QRM+ bearings and the proper steps to take to ensure correct bearing play and increase the lifespan of you wheels systems. When buying a Mavic wheel system from one of our dealers, remember to have the following steps done, either by the dealer or yourself, to get the full performance for your wheels.

 

1. HUBS

1.1 FREE PLAY ADJUSTMENT

 

Hub play must always be gauged with the wheel fitted and tightened in the frame or fork. Tightening the quick release skewer significantly increases the lateral pressure

exerted on the bearings.

 

Therefore:

• if there is play in a wheel not fitted into the frame or fork, it may disappear once the wheel has been fitted;

• if there is no play in a wheel not fitted into the frame or fork, it is possible that tightening the quick release skewer will over-stress the bearings, thus damaging

them.

 

Adjust the adjustment nut by fully tightening it and then untightening it by a 1/4 turn, so as to close the quick release lever (CLOSE position) with a suitably large force.

However, a too large tightening force may damage the bearings.

 

This tightening force is a subjective parameter that is directly dependent on the end user, and as such it is difficult to accurately determine the optimum bearing adjustment

at the factory.

 

In order to avoid any problems for your customers, we factory set bearing play by simulating an extreme quick release tightening force.

There is therefore likely to be some play in the hub of a new wheel fitted to a bike with a lower quick release tightening force than that used in the factory.

Apply the following procedures to set the amount of play.

 

 

WARNING: Adjusting the play is a delicate operation which consists of identifying the balance point between play and no play.

Having no play does not necessarily mean that the hub is correctly adjusted as the bearings may be over-stressed.

 

1.1.1. QRM+ HUB

This hub has an adjustment nut on the left hand side of the wheel compatible with the hub wrench M40123.

This very simple system allows very accurate and quick adjustment of bearing play.

 

PROCEDURE

 

Tools needed

• 1 hub wrench M40123

1. Fit the wheel in the frame or fork and tighten the quick release skewer using a reasonable force;

2. Delicately move the top of the wheel to the right and then the left of the bike to feel the play;

• If there is some play, lightly tighten the adjustment nut using the hub wrench M40123 and check for play: repeat the operation as many times as required until there

is no play;

• If there is no play, to be sure the bearings are not over-stressed, untighten the adjustment nut until some play can be felt and then carry out the above operation.

The 4 lugs of the hub wrench M40123 must be fully inserted into the holes of the adjustment nut, making sure to correctly position the wrench against the nut

(on Crossmax XL Disc and Deemax UST front wheels, only the 2 lugs at the extremities of the wrench are used).

 

 

To avoid damaging the bearings due to over tightening of the adjustment nut, the wrench M40123 is made from resin: a sort of safety valve; the lugs will break before the

bearings are damaged.