Under fairly high pedaling load, my drivetrain makes a loud (and highly disconcerting) “CLUNK” noise. I would say this typically happens 5-10 times during a 25-mile ride. Having replaced my cassette, chainrings, chain and bottom bracket, the problem still persists! This leads me to believe that the source of the noise pertains to a fault with my rear freehub (Hope Pro II circa 2008). I’m not an expert on hubs, so I was wondering whether anyone else has experienced a similar issue?

Thanks.

Haven’t had the same issue, but i’d suggest that a 6 year old freehub could probably do with replacing.

worn and slipping pawl(s) would be my guess.

As long as the ring inside the hub is ok it’s a cheap and easy fix to put new pawls in there.

It could well be the pawl springs (or even the pawls themselves). The springs can (and do) break – and rust if any moisture gets in.

This was the problem on mine – the symptoms sounded exactly the same.

They are cheap and easy to replace if this is the case – £2.88 for springs here: Linky

Thanks for the tips.

Is it a straight forward procedure replacing the pawls/pawl springs? Would I need any special tools?

Have a look at this. [video]https://www.youtube.com/watch?v=XbOEc0Jrz9A[/video] gives you an idea of how to remove freehub etc. I’d check the bearings whilst you’re there but you don’t need to change them if they’re ok.

[edit] this one covers just the freehub;

[video]https://www.youtube.com/watch?v=J-09KxrRIbY[/video]

The only thing with the Hope vids is they make it look really easy- the process is simple but actually getting them into bits can be quite hard work. But yeah, get the freehub off, have a look, nice simple kit to work on.

Longnose pliers and grease is all. Not too much grease mind or it’s goodbye clicky noise 🙂

Be careful if you find that one (or more) of the pawl springs has snapped.
The grease inside the freehub space will contain some of the finest shards of rigid metal you’ve ever seen. And see them you will, as they go straight through skin like a mad thing… and can be an absolute nightmare to extract later!
When these leaf springs snap, they shatter widthways into several thin strips and will lurk in the dirty grease.

I had the exact same problem with a one year old hope hub. Turns out the grease was causing the pawls to stick and thus not all of them where engaging. Works much smoother with a lighter grease. I have even used 3 in 1 oil with no issues.

My rear Pro 2 seems to be slipping this week under high torque (pushing up a quick climb in the wrong gear). I was guessing it was the freehub or pawls too (cassette has done 9 months, new chain 3 months ago).

Is it easy enough to do a full hub service as shown in Hope’s video without their specific tools? Any essential tools I should try to borrow (vs ones that just make it a bit easier)?

you only need ‘tools’ for the bearings to stop them getting damaged when pressing in but a lot of people bodge something up with sockets etc.

Had similar recently with my Cero AR30 rear wheel. Turned out it was dirt in the engagement, cleaned the pawls, springs and ratchet ring and now totally silent.

Lornholio – the only tool I bought was the tool to put the seal back in place, but in hindsight I don’t think I really needed it.

I had a similar age hope pro hub that started with a similar noise until the body exploded whilst pedalling uphill. Check all the spoke holes on the flange for signs of cracking on any of them. If there is return it to Hope and you should find they will replace the hub body free of charge like they did with mine.

Most likely it’s the freehub springs/panels that need changing, might also be the outer bearing in the freehub that has gone meaning that here is play in the hub under hard pedalling load.

It’s me again. I just wanted to say that I replaced the pawl springs and the problems went away completely. Turned out to be a pretty simple procedure, which didn’t require any specialist tools. The seal slotted in easily with just my fingers.

Thanks for your help everyone!!!

As everybody else has said, likely pawls – but while you’ve got the freehub and cassette off, just check the inner two bearings for wear as well

So is it most likely to just the pawl springs or could it be the pawls themselves? Just figuring out what to order.

I’ll probably leave it until autumn though, as mine only slips when I’m trying to push up a steep section in too high a gear. I’m not going to damage the ratchet if I’m careless in the meantime and get into this situation now and again, am I?