|
MountainBikeReview.com's Forum Archives - Save some Weight
|
|
Fox Pro-pedal vs 5th Air vs Romic (just research, no riding) (6 posts)
|  Fox Pro-pedal vs 5th Air vs Romic (just research, no riding) | dirtdad
Jul 10, 2003 6:14 AM | | Well, no rest for the wicked. I am on to my next project, an Ellsworth ID. My choice came down to it and the Turner 5 Spot. Not an easy choice, but mtb market helped decide.
Both of those bikes use the Romic rear shock, which many longer travel / freeride bikes do. I have seen several riders running them on Truths, too. The Romic really enhances pedaling performance. It is a great shock but it is very heavy. 800g + according to weight weenies. After talking to Turner, Ellsworth, Romic, and Fox, here is what I learned.
The progressive 5th or 5th air are not the right shocks for these bikes. First off, they are rising rate shocks, and the frame designs are also rising rate. Not a good combo. Also, the Romic is not a true platform shock, it just has the right non-linear damping curve. Fox pro-pedal should give very comprable performance, and it is like a Romic air, not a 5th air. It seems a very good choice for lightweight, fully active, rising rate suspension designs.
However, I must add that everyone I spoke with was aghast at the notion of an air shock on a 6" travel bike. Besides that, the Romic shock is practically worshipped by freeriders. I couldn't believe it. Finally, at least in my case, the Fox is not delivered in the most optimal size. The Romic I need is 8" x 2.25", whereas the biggest Fox is 7.8x2, which will work, but reduce travel from 6" to 5". |
| 5th Air for my Truth | mbdurham
Jul 10, 2003 7:18 AM | | That sucks I was looking forward to a 200gram 5th Element for my Truth. But if it's not recommended for the ID maybe I will just stick with my cloud nine. |
| I'm playing with a Fox ProPedal AVA on my Hollowpoint... | næstep
Jul 10, 2003 8:04 AM | | I've been curious about the SPV-type shocks and just this week installed a Fox ProPedal AVA Float on my '03 Hollowpoint. It's replacing the Cane Creek AD12 that I've been riding on this bike for the past few months.
I don't know that the ProPedal feature is truly SPV by the strictest of definitions. It seems more to me like the dual stage TPC+ compression damping on my Manitou Xvert fork. Compression is more highly damped early on (but not locked out, and not "heavily" damped), and a second set of ports speed up compression for bigger hits. I don't know if the second stage is position sensitive or impact sensitive, but I should be able to figure that out as I get the shock dialed in and spend some more time on it.
I do miss having any independant control over the compression damping with this shock. Both rates are preset at the factory. With a suspension design like dw-link on the Hollowpoint, correct sag is critical, and directly dictates the shock's air pressure setting within a pretty narrow band.
In fact, there are no additional adjustments on this shock that aren't found on the standard Float AVA shocks. A 'ProPedal Damping' sticker is the only indication something is different. There is still only one air valve, the standard Fox rebound adjuster wheel, and the AVA ring.
The AVA (air chamber volume) adjustment is a form of controlling the compression damping, but only effects the tail-end of the shock stroke, so nothing can be done to moderate the shock's movement in the 'slow' near-static-sag pedaling position.
Even with the smallest chamber setting (AVA dialed all the way in), the total air volume is pretty large compared to most other air shocks (30% larger than Fox's standard Float, according to their literature). So while still a rising rate shock to be technically correct, it's a fairly flat rise in the smallest setting and even flatter nearly linear in the largest.
I've still got some tuning to do. I haven't even messed with the rebound control yet (for now it is fully open and has a mild kick to it on deep rebounds). On the Hollowpoint, I have the rebound down to the '3' setting (about 2/3 of the largest setting) and am going to adjust it a little smaller to try and get a sharper spike towards the end of travel.
For my 215 pounds on the 5" travel Hollowpoint, I'm running about 230psi to achieve 12mm (~30%) sag (but this is another area I want to experiment with some higher pressures). Given the low PSI:rider weight ratio, this air shock might be a good candidate for a 6" travel bike (never thought I'd say that about an air shock). For comparison, I've been running my AD12 at about 245psi (+30 over rider weight) on this same bike.
Anyhow, hope that adds something of value to the knowledge base. I'm going to post more later when I get some more miles on it.
næstep |
| re: Fox Pro-pedal vs 5th Air vs Romic | mypalthetortoise
Jul 10, 2003 8:22 AM | | Here's another option...
Go with the Romic shock, (it's awesome and it really does mimic SPV technology) and get a Ti spring. Ellsworth says the Ti spring will be out late this summer and it saves a quarter pound! |
| re: Fox Pro-pedal vs 5th Air vs Romic (just research, no riding) | emilio socal
Jul 10, 2003 3:10 PM | | Fox AVA ProPedal for sure. We're now experimenting with the 5th air on the Truth / ID. The platform concept helps bike that either have chain torque induced suspension activation or are overly ride height sensitive. Neither of these concerns affect the ICT bikes (Truth / ID) so it's a fix we don't need. That said the 5th is wacky light! So far we've found it's a little tricky to get dialed just so. That may be because we're trying to mask the SPV quality it has so maybe we're chasing full activity against the shock's wishes. The 5th air may be just the ticket for weight weenie leg shavin' XC racers on Truths (thats' me). The ProPedal on the other hand is ideally suited to the ICT bikes. It simply has a non-linear damping curve to help filter out your leg mass flailing up and down (as næstep observed).
We're really impressed with how sensitive the damping is when descending on the ProPedal when compared to the Romic. As far as ultimate butteriness (technical term) the Romic is still the sh** but the ProPedal is way closer than any other air shock has ever been.
If you go ProPedal on the ID, let us all know how it works. |
| How light is "wacky"? | B R H
Jul 10, 2003 3:17 PM | | I'm curious what the actual weight on the 5th is for a Truth. Also, how does it compare to the Cloud 9? I've been much happier with the Cloud 9 than my old Fox Float. |
| |
|
|
