Saturday, December 10, 2011

Freehub pt. II

It's that time of the year again, when the temperature goes below zero, and bicyclists like me, who've neglected to maintain their freehub regularly, end up looking silly and/or dead. That's because when a dirty freehub freezes, the pedals spin freely both backward and forward, thus making the bicycle not move forward while pedaling. If it happens in the middle of a busy intersection, with a truck speeding towards you, you might end up looking silly, pedaling furiously without moving, and dead. If it happens in a more safe environment, you just end up looking silly. Yeah, it happened to me last year. I mean the looking silly bit, not dying, obviously. 

So, after attempting to commute to work one frosty morning with a not too well maintained MTB, and ending up looking silly, it became necessary to dismantle this:



Also, I wanted to do it because it is fun.

As you can see, the freehub is kind of dirty and rusty, which is no wonder with all the mud, water and crap it has to endure.

Some of the lock nuts on the axle were so tight I didn't manage to unfasten them with my not-so-professional collection of tools:


In fact, I even had to resort to DIY tool modification, as I didn't own a 17 mm flat wrench that was required. Luckily, these flat wrenches are soft so it is easy to file a 16 mm one into a 17 mm one: 


 It didn't matter that I couldn't unfasten the lock nut on the brake disk side though, because the ones on the drive side came off. 


 Here's the dirty freehub body and axle:


And the freehub body after some washing with solvent and drying with compressed air: 


The freehub is clearly finished though. It hardly even rotates when turned with fingers and needs to be replaced. Also, the surface on one of the bearing cones has suffered badly, and has to be replaced as well:  


But then again, although not visible in the picture, the surface of the bearing cup of the rear hub has been damaged as well:


It is not possible to replace just the cup, therefore the entire rear hub should be replaced. Possibly, I could just put it all together and ride on until spring, but that wouldn't seem a satisfactory solution for a prefectionist perfectonoist not too shabby a guy anyway like me.

Let's see. The rear hub model is Shimano FH-M756: 


A new rear hub costs some 50€ at CRC. BTW, a freehub body for 9 speed costs more than 30€, so it would seem more reasonable to get the rear hub even though I needed only the freehub body.  

But if I purchase a new rear hub, then who will build the wheel for me? No way I can do that myself. You know, I do intend to learn wheelbuilding, but I'd rather do that when I have more time, patience, space and a wheel truing stand. Like when I'm retired. In a garage. With a wheel truing stand.

Besides, a set of spokes costs money too. And if I intend to replace the rear hub and the spokes, should I replace the rim as well while I'm at it, as a new one only seems to cost some 30€? The old one seems okay, but with all the trouble and cost, there seems to be no point in saving 30€.


So, let's see... rear hub 50€, rim 30€, spokes 20€. If I'm not mistaken, that adds up to... carry the one... 100€. As I don't intimately know any wheelbuilders, the labour would cost some 50€. Perhaps I better look into new factory wheels. Damn, this thing is just spreading... soon I'll have myself convinced that there's no point in repairing this one and I must get a new bike altogether. "My house is dirty; buy me a clean one!".

But hey, wait a minute... what's this section, MTB Custom Wheels? Wow, this looks good. You get to choose a rear hub, rims, spokes, nipples and rim tape. The price seems reasonable too. For some 100€ I could get a similar, brand new rear wheel that I have now. Oh, and must check the bearings on the front wheel as well before ordering.

Besides, what's 100€ for maintenance of the vehicle I mostly use to transport my physical being to and from work? Nothing! What would I get with 100€ if I drove? 60 litres of gasoline. What would I get if I used public transport? Two months. Phew. I'm beginning to feel it's my holy duty to order new custom wheels, both rear and front, as soon as possible, if only to ensure the uninterrupted supply of sustenance for the family. With possibly just some small things on the side...

If only my wife read this blog. Then I wouldn't have to justify all the online purchases, verbally, yet again.