Any reason not to?
No.
32 Vanillas and RP23 here. Probably endless numbers of bikes out there with air cans and coil pikes too...
The assumption that coil fork and air shock rear is wrong has always made me laugh.
Ta - only ever had hardtails before
Why not, out of interest?
My last full suss had Air Z1's and coil vanilla out back...
Dunno really, like Chunky I've probably read somewhere that it "should" be air/air or coil/coil
Air DHX 5.0 rear and Coil Marzocchi Z1 FR lights front here.
How may HTs run a coil fork? 1000s and they have nothing taking up the rear at all.
I don't see why anyone would ever question it.
Don't do it!
If you do the left over electromagnetic energy generated by the rapid compression and rebound of the coil spring will charge the outside of the air chamber of the shock leading to massive stiction problems and rapid seal failure.
What about the other way round?
I'm running Solo Air Lyriks and a Coil DHX on my bike and it works fine. There is absolutely no reason, other than the one Glenh gives ;-), to not run a mix of spring mediums.
if your coil fork suffers mid stroke blow through too, then why not 🙂
I've always had air/air FS bikes before but my Pitch is coil at the front, air rear and is the most balanced bike I've yet ridden....
🙂
what about the other way round? Same thoughts?
I run the other way round!
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Its not just by chance either, its a very deliberate setup and Im very happy with it.
I've run all possible air/coil combos at some point, and worked out that this is the best compromise for me.
07 onwards Fox 36R's now give performance that is 99% as good as the Vanilla 36's. The same cannot be said for Talas forks unfortunately. That 1% loss is worth the weight saving.
My forks run at abou5 50psi - the very large air volume leads to low stiction and ramp up, hence the 36R being superb. 32R's have never quite been so sensitive IMO.
However, neither the DHX air or Float gives acceptable enough small bump performancem when compared to a coil.
This setup gives me the best, sensitive, bump eating performance, with a small weight saving over the Vanilla forks.
I love this bike - it comes in at about bang on 30lbs yet the suspension performance is second only to a full on FR/DH rig.
Ti spring when I can afford it.
Good setup IMO.
In theory at least, it's easier to balance air/air or coil/coil rather than a mixture but assuming you get the balance right then there can't be many goo reasons not to. For my personal riding style though I'd prefer to have any weight further forward ie in the fork rather than at the rear so I'd gravitate towards a coil fork. Makes sense for the type of riding I do.
When jumping and dropping I find a light front end more unnerving than a heavier one.
Why would it be easier to balance in theory? With my engineers hat on then it's easier to balance air/coil spring rates - your coil will increase in descrete steps (e.g. 400lb, 450lb, etc) wherease your air shock is essentially infinitely variable meaning that you can achieve exact balance. With coil it'll never be exactly right (unless you wind your own springs).
I used to run front coil, rear coil, then changed to front air, and now i've just changed to air/air (as of ten minutes ago!).
Snotrag - I'm the same (just got a new coil sprung frame) so time will tell how suitable my setup is as I mainly just transfered my existing kit over.
From what I've read front air/ rear coil is a better option than front coil/ rear air due to the type of work the shock is doing (ratioed) vs the forks (linear ie 1:1) but it may be b0ll0cks.
I guess it's mostly about the extra stiction/ friction compromises vs lost weight of an air spring over a coil one.