Throbbing hum from rear wheel - ksyrium

[ishaw]

Nothing is ever easy is it. Bought some ksyriums with a campag freehub but needed Shimano. Sorted a Shimano one and fitted it as per the campag one (little washer between the freehub and hub body) and it all seemed fine. However when spinning up and freewheeling, there is a sort of pulsing hum that occurs. Any idea what this might be?

I may have to refit the campag to see if it does it with that on to rule out the replacement Shimano freehub, but hoping I can get a diagnosis and remedy.

 

[ishaw]

A bit of research lead me to a video along this topic.

I've taken off the freehub, given it a good clean and degrease, refitted everything after using the suggested mineral oil as a lube and it's marginally better. Not knowing what these wheels are supposed to sound like freewheeling it could just be how they are, though when spinning in hand and holding the freehub, there is a degree of feel through it that in my mind doesn't feel right. The hum/pulse has lessened.

I do seem to recall reading something about the derlin bushing being an issue on these wheels. Could it be that? If it doesn't do it on the campag freehub can I swap the internals out? Is there another option? Is the mineral oil a good idea? On MTB hubs, grease is usually suggested, though not much.

 

[foz]

more than likely the delrin bushing. stupid design that one.... no idea if it can be swapped between the campag and shimano freehub bodies - if you can take them apart then I suggest measuring to see if they're the same?

 

[ishaw]

In theory they should come apart as there's a kit to replace them.

https://ebay.us/m/QG7f2V

Need to see how the bushing can be removed without damage after testing the campag one as is.

Anyone done this? I'd there a kit available in the UK?

 

[pigman]

Ive had 2 sets of ksyriums where this happened. The first I gave away for someone to use on a turbo as the rim was worm out. The second, I squirted chain lube into the freehub and it seems to have cured it for now