Freehub mystery hole

[Big John]

I've fettled many a freehub but due to the sheer number of different flavours I don't profess to be an expert. However, this is the first time I've come across a freehub that has a hole drilled into it (as shown in the photo). I'm presuming it's for occasional lubing of the tiny bearings/pawls. My first thoughts were "Genius!" but am I right? Is that what it's for?

 

[Marchrider]

I wonder if it has been put in by someone so as it can be lubed - I once thought of doing that

Interesting yellow plastic thing in the end, I 3d printed something similar for mine, the metal dust seal thing gets all bent and becomes useless

 

[Big John]

I've not examined the yellow thing, I'll be honest. I guess it's a fancy seal of some description. This is off a fairly old wheel, by the way. It's certainly off an old Peugeot bike that we're breaking up for the parts at the bike charity I'm involved with. An absolute Aladdin's cave for bike enthusiasts.

 

[Smokin Joe]

If it's an old wheel it is quite likely for lubrication. Back in the day it was quite common to have a hole in the center of the hub for that reason, protected by a circular sprung dustcap.

 

[Marchrider]

If it's an old wheel it is quite likely for lubrication. Back in the day it was quite common to have a hole in the center of the hub for that reason, protected by a circular sprung dustcap.

could you explain the circular sprung dustcap - picture would be good

the problem ith the hole where it is - the centrifugal forces when its spinning would force all the lube out - and that hole would be difficult to seal with the cassette lid over the top of it

 

[Smokin Joe]

you can see the sprung dustcap in the centre of the hub, probably for grease rather than oil on your freehub.

 

[lostinthought]

I've drilled a similar hole (smaller, though) in the Campag Record free hub shell on my bike, in order to open the internal circlip which trapped an inner sealed bearing. There are various tricks to access it, and probably a highly expensive special tool , but this method was suggested, and works fine.

I sealed it afterwards with a dab of silicone sealant or something. I was going to tap it and put a grub screw in it for neatness, but never happened.

The hubs have the grease port and snazzy spring steel cover too. Looks like this (not mine, random pic):

 

[azbikes]

I wonder if it has been put in by someone so as it can be lubed - I once thought of doing that

Interesting yellow plastic thing in the end, I 3d printed something similar for mine, the metal dust seal thing gets all bent and becomes useless
View attachment 764292

If you been one of those metal types, there's a socket head that fits perfectly and you can straighten it out that way. But you do have to be careful removing it off of the socket as it fits snug.

 

[azbikes]

If you been one of those metal types, there's a socket head that fits perfectly and you can straighten it out that way. But you do have to be careful removing it off of the socket as it fits snug.

Meant to say 'if you've bent the dust cap' while trying to remove it from the cassette... There's one socket drive that fits down inside that gap and you can pound it down and flatten it out so you can reuse it. But it is a tight fit you have to be careful prying it off the socket.