Novatech freehub issue

[MTB2223]

This weekend I did a good clean of my wheelset and found some unexpected wear on the freehub of my Novatec D772SB (front D771SB). I've got these hubs now for about 8 months and I cannot believe this supposed to be in this short time. Some cogs damaged the freehub. It looks like Novatech made the freehub of soft material or is this a production failure ?

Anybody knows if there's a stronger freehub available ?

[Carbon_Dude]

It's funny, Bitex told me they had steel or AL available for my hub, looks like some AL free hubs don't hold up well with some cassettes, maybe that's why they offer a choice.  Maybe Novatec offers something that is stronger, but heavier.

[cmh]

This weekend I did a good clean of my wheelset and found some unexpected wear on the freehub of my Novatec D772SB (front D771SB). I've got these hubs now for about 8 months and I cannot believe this supposed to be in this short time. Some cogs damaged the freehub. It looks like Novatech made the freehub of soft material or is this a production failure ?

Shit, dude, ANY aluminum freehub will do this. I could go out into the shop and grab a Hope freehub, a Stan's Freehub, an older American Classic freehub, probably one or two more... all aluminum, and all far, far worse than that one. Aluminum is a soft metal, this is going to happen. American Classic has a brilliant design where they have steel inserts in the aluminum freehub body which prevents this, but they patent it and don't let anyone else use it. Of course, Novatec has copied it in some of their hubs. (but not this one)

I've got some aluminum freehubs so marked up that I have a bitch of a time getting the cassette off. Higher end cassettes - like you have - will prevent this from being an issue by putting bigger cogs (which have higher forces involved) on an aluminum or plastic carrier. Cheap cassettes have individual cogs and will do this all the way across.

If you're having trouble getting the first couple of cogs off, you can lightly file the outer diameter to kill the little mounds that form from this happening, but as long as you've got an aluminum freehub, this is going to happen, and doesn't represent a failure of the freehub at all.

[cmh]

So I went into the shop. Here's a Hope aluminum freehub:



Here's a titanium Zipp road freehub showing some small markings (although road has much lower chain tensions and smaller cogs, so much smaller forces at the freehub splines):



And finally, even a replacement Hope STEEL freehub shows sign of marking, because I'm such a studly beast throwing down such huge wattage numbers... (or I'm a big sumbitch that uses the granny gear far more than I should, which results in ridiculously high chain tensions and thus really high forces at the freehub splines)



So again, you've got nothing to worry about. If it bugs you, you can swap to a steel freehub, but that's a weight penalty. On the Hope hub, that was about 60g if I remember right.

[MTB2223]

Whow, didn't know this was a common (and accepted) problem.

Did a search on internet and found that Novatec have a ABG ( Anti Bite Guard ) version of this hub:


"The D772SB uses the new 4-Pawl freehub from Novatec ensuring fast and secure engagement, every time.
This freehub includes the ABG feature to prevent damage to the 7075 alloy freehub body."

If I'm going to replace my freehub, I'll go for this one.

[Carbon_Dude]

Given that a cassette on an XD hub screws down onto the free hub, this issue was addressed when SRAM designed the new XD hub. 

Here is a picture of mine that had the failure around the pawls but after two years of riding it, no gouges in the free hub body.

[MTB2223]

What oil/grease did/do you used on the pawls ?

[Carbon_Dude]

In that picture, it was the BiTex factory grease, I had not serviced the hub since I built the bike.  When I installed the new hub, I applied some DT Swiss ratchet grease.  The grease is specified for all DT Swiss free hubs so I thought it should work fine for the BiTex hub.  At $18 for a small jar of grease, it had better work well.