Fitted my light bicycle carbon rims at the weekend and went on a couple of rides. They feel incredibly harsh, have turned my full suss into a bone shaker! Has anyone else experienced this out of interest?

They feel great on the smooth sections but terrible over roots/rocks. Only two rides in so I’m not going to give up on them just yet, but will be dumping them for flows if I can’t get used to them

Yeah definitely noticed it with mine

Get em tubeless and embrace the lower psi

And run a wee bit less pressure in the shocks

I have my ally wheels for winter uplift days and messing about, save the carbons for racing and xc stuff, I a dapt pretty quickly between the 2, I love the quick acceleration and stiffness thru corners of the carbon wheels

Everything I’ve read about carbon rims says this will likely happen. Losing the flex from alu rims means you’re likely to need to change your suspension settings. They should give sharper, more precise steering & less rolling weight though. Pros & cons…

Thanks guys, glad to hear its not only me. Front is low and tubeless but the rear could probably come down a bit

The problem with all suspended bikes is that when you’re cornering the suspension is pointing in the wrong direction to deal with bumps half as well as it does in a straight line – so a degree of flex in the rims and frame is needed to stop the bike nervously jittering in corners.

What rims are the pro enduro & DH racers using? Does the lower weight of carbon save the enduro racer enough energy to compensate for possibly less grip in the corners? What about when efficiency doesn’t matter and it’s all about shaving tenths on a few minute run?

What spokes did you build them with? Carbon rims are fairly soft (in the grand scheme of things) vertically but tend to be stiff laterally, which makes them feel quite different. They are definitely best served with a very light spoke to allow for some lateral flex, and while you’re at it a locking nipple to compensate for the vertical softness that can cause spokes to unwind their nipples quite easily.

Perhaps a silly question, or possibly not… Are you running your tyres at the same pressure as before?

If I run a few extra psi in my tyres I’m always surprised how much more ratterly my bike feels over the bumps.

Thanks guys. Maybe have messed up on the spokes then as I went with DT comps as I wanted them to take some abuse. Maybe I should have gone with revs or super comps.

Ill definitely try lowering the psi in the rear tyre as its relatively firm. Although I did reckon that most of the knocks came front the front, which is pretty low in terms of psi

Interesting. So would Carbon wheels be less suitable on a fully rigid bike?

What spokes did you build them with? Carbon rims are fairly soft (in the grand scheme of things) vertically

I don’t agree with that, my lb rims were rock solid vertically compared to alu rims. IIRC there is a demonstration of the vertical stiffness of carbon rims in this vid too https://www.youtube.com/watch?v=H3IE0IH0i4E

Isn’t vertical stiffness just dependent on how much tension you put through the spokes. I rim without spokes is going to take bog-all force before it collapses regardless of what its made of.

Lateral stiffness definitely makes a difference since the spokes are not strong in that direction – but vertical??

Vertical stiffness will be affected as the stiffer rim will transmit the force to a higher number of spokes more evenly.

No idea how noticeable this would be in the real world though.