Rockshox bike shocks

[lamboracer]

Hello all,

I was curious to know if anyone has had any experience or know of any teams that make use of the Rockshox Kage RC shocks on their vehicle.

https://www.sram.com/rockshox/products/kage-rc

Thank you for your time.

[troot]

Is there a particular reason you are looking to use a MTB shock rather than a purpose built one? I understand in the past availability of application specific dampers was much less but now there are many options with travels suited to FSAE and already feature spherical bearings at both ends.

[MCoach]

No idea on using a mountain bike shock these days. However, for the same price, you can get a set of these bad boys:

http://www.kaztechnologies.com/quarter-midget/

[lamboracer]

The only reason I am looking into MTB shocks is for the price. Our budget is extremely small this year. Last years team made use of the Jupiter 5 shocks in the front and the quarter midget in the rear. I wanted to go to the same shock on all four corners. With the current geometry of our suspension it wouldn't allow the quarter midget shocks to be used and have a useful motion ratio.

Thank you.

[jd74914]

The reason people generally stay away from MTB shocks is that they tend to have inconstant damper curves (ie: shock 1 has a much different curve than shock 2) so tuning is more difficult. If you can correct this, even if it means buying a few extras, dynoing them and keeping the 4 closest ones, they might be a good option.

[SkeH14]

Hey lamboracer,

Although the options from Rockshox are appealing at their price-point, there are a number of reasons to avoid running them on an FSAE car.

First and foremost is the lack of adjustment and variation in performance that jd7914 mentioned. Rear mountain bike shocks only have to deal with one rider and one rear wheel. The rider can set the shock up to their preferences. Small differences between shocks or damping curves won't be noticeable or important on a bike. But on a racecar with 4 corners, small differences in shock performance from corner to corner could seriously affect car behavior in different directions (think about how bad skidpad would be if each side of a car behaved differently).

Second, mountain bikes shocks are designed for a very different low speed and high speed damping than a typical car shock would be. Bicycle shocks are designed to resist low speed compression that is typically caused by pedaling a bike. When riding a bike this low speed compression decreases pedaling efficiency so engineers aim to eliminate it. In a racecar this low speed compression is important for weight transfer and car pitch. you need to decide how you want to use low speed compression to your advantage. Finally the high speed compression side of bicycle shocks are designed for big impacts at low frequency, typically associated with hitting a jump or a rock. These aren't the type of things that you would see on a FSAE track, and this means the high speed compression is likely improperly tuned to your needs.