Oscillating Sound of DT Swiss Freehub on Roval Wheels

buckmulligan

I've just picked up a set of Roval CL40 wheels and the first thing that I noticed is that freehub noise has an annoying oscillating sound to it. It's absolutely fine when you're pedaling (so nothing to do with the rim, tyre or valve placement) but when coasting along the freehub ratchets make a pulsing sound, with frequency of the pulsing directly related to how fast your wheel is spinning. I just had a quick Google and it seems to be a common problem, which someone on The Paceline Forum described quite well:

The freewheel noise kind of pulses as the wheel spins. So if a quiet freewheel is zzzzzzzzzzzz and a noisy freewheel is ZZZZZZZZZZZZZ this one goes ZZZZZzzzzzzZZZZZzzzzzz. The noisy/quiet parts are in the same spot on the wheel with every rotation.

I've already taken the freehub apart out of curiosity and everything looks good, clean and well-lubed. It uses DT Swiss internals, which look like this:





I'm wondering if the flimsy wire springs are pushing the two star-ratchets together with uneven pressure to cause the pulsing sound? General consensus seems to be that it's nothing to worry about, but I'm still finding it quite annoying. Has anyone else experienced this on Roval or DT Swiss wheels and know of a solution?

Also what lube or grease should I be using in this freehub system? I'm not so keen on just packing it with grease to keep it quiet because that seems like it'd just be masking the issue rather than solving it!

sungod

i've had it on two wheelsets (lw obermayers which use the dt swiss 190 freehub, in turn a lighter version of the 240), aside from the noise it's not really a problem

it may well be due to the springs applying slightly uneven force as the star ratchets rotate relative to each other

the grease needs to be light and applied sparingly, if you pack the thing with grease or use too thick/sticky grease the freehub will not work correctly

dt swiss say to only use their 'special grease' (echoes of the league of gentlemen), this is grease with added mineral oil, it's available in small tubs for a big price, but a little should last many years

the dt swiss service guide has all the details

as an aside, also check the bearings in the freehub body, you can pop off the seals in situ and pack these with grease - if they run out of grease and/or water gets in they will fail badly, which is what mine did with not even 18 months riding, i tapped out the bearings and pressed new ones in, clearly they need checking more often

Nick Payne

I have a couple of pairs of wheels with the DT star ratchet freewheel mechanism, and they both make this same noise that isn't constant when freewheeling. It doesn't seem to cause any damage - one of the pairs of wheels is getting on for 20 years old and the freehub mechanism is still fine. As for the grease to use on the freewheel mating surfaces, I've found that ordinary grease doesn't work, as the freewheel doesn't engage properly, but using Weldtite TF2 teflon grease, the freewheel works without any problem - I've serviced the older of the hubs several times and not noticed any damage from using this grease rather than the DT Swiss special stuff.

https://www.weldtite.co.uk/tf2/

ugo.santalucia

It's fine... don't worry about the freewheel noise

Bobbinogs

I liked that Weldtite page...it had little symbols to help people understand what weather the lubes were for...the lubes were called "Dry weather", "Wet weather" and "All weather"...nope, no clues there!