What is "isopulse"?
 

As I'm shopping for wheels, i've come across the term "isopulse", specifically in some of the Mavic rear wheels.

Can anyone shed some light as to what it is?
And does if it has any benefits to a rider that is in the 190+ range?

I did see the description http://www.mavic.com/en/technology/wheels/Isopulse
but it doesn't tell me much. :twitchy:

It means when you break a spoke in back, it'll more likely be on the non-drive-side than the drive side.

Lacing the non-drive side with cross lacing (required in a rear wheel to transmit the drive torque to the rim) allows more balanced tensions between the drive side and non-drive side spokes than a more traditional construction (cross both sides, or crossed on the drive side and radial on the non-drive side). I don't think there are any weight-specific advantages to the construction, and I doubt you'd be able to tell whether you're riding an Isopulse wheel if you were doing a blind A/B test.

Isopulse lacing does force the torque to be transmitted through the entire hub body and onto the non-drive side flange instead of putting all the strain on the drive side flange of the hub. If the hub is engineered for it (and it should be) this also shouldn't be anything you notice.

It sounds like isopulse is more of a "spoke breaking strategy", sending it to the the non-drive side, as opposed to providing added benefits for stiffness?

Isopulse is one of those words marketing people create to justify their own existence.

actually the design makes sense from a engineering sense. The spokes on the right flange are under higher tension than the left flange, due to the need to have the wheel dished...making those spokes riadial means they are carring any additional tension when you unleadh your 1500 watt sprint, as they are radial laced. The left side spokes are under lower tension to start with, so the addtional tension due to transmitting your massive power from the hub to rim is not a problem.

On the other hand I have some Easton EA90Sl wheels which are laced the opposite way as these Mavics, i.e. radial spoked on the left flange, and they work just fine.

The spokes on the right flange are under higher tension than the left flange, due to the need to have the wheel dished...making those spokes riadial means they are NOT carring any additional tension when you unleadh your 1500 watt sprint, as they are radial laced. The left side spokes are under lower tension to start with, so the addtional tension due to transmitting your massive power from the hub to rim is not a problem.

On the other hand I have some Easton EA90Sl wheels which are laced the opposite way as these Mavics, i.e. radial spoked on the left flange, and they work just fine.[/QUOTE

I see that as a problem since half of the NDS spokes are actually losing tension under pedaling torque. An already low spoke tension losing more tension is going to fail faster. Nice job Mavic! :lol:

I built my current wheels this way and have had no issues with them due to the lacing (dogbone hole pattern threw off my spoke length calculation and I had the wrong length spokes so I had issues until that was resolved) pattern. I did this with Kinlin XR300 rims, Formula RB-210 hubs and Sapim CX Ray spokes.

Incorrect.

I don't expect everyone to understand.

I havent heard of many Mavic wheels failing. Save for those R-Sys wheels......

do radial spokes make it less likely to taco?

Asymmetrical lacing is "fun". It gives a fresh look to wheels in the market. The "theories" behind going radial NDA or radial DS all seem great on paper, but in reality they make little to no difference. Look back through archives of wheel iterations and you will find that companies have touted that they were great because they did it one way - only to swap to the other way a year or so later.

Studies, theories, etc. All great stuff. As an engineer I am just a likely to mentally m*bate over it all too. Problem is reality. My experience as a wheel builder has shown that over the long run asymmetrically laced wheels tend to experience spoke failures more often. Chalk it up to anything you'd like - spoke quality, build quality, etc....but I have found this to be true across multiple manufacturers, designs, build configurations, etc. It simply doesn't last as long.

Since Psimet beat me to the most cogent post on this thread, I'll just have to chime in with a second for "isopulse" being marketing.