Single Speed Hub Dissasembly Help
 

Hi,

Just needing to ask a bit of a newbie question. I have a flip flop hub, and wish to dismantle the hub in order to repack the bearings, but it doesn't look like I can remove the freewheel on this? Am I supposed to dismantle the hub from the the fixed gear side, and just dribble oil into the brass cased ratchet opposite (single gear) side? If I try to pull the ratchet apart with a pin spanner, am I going to destroy it? Basically I just want to get at the wheel bearings, so I can repack them.

Cheers,

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If that's a typical single freewheel there should be 2 notches in the inner rim, which take a freewheel remover. Make sure you know how to use these because it's very easy to damage the notches (or remover or both).

However there are hubs where the freewheel in integrated with the shell rather than a separate module threaded on. I doubt yours is this type, but wouldn't rule it out, especially if the freewheel doesn't have a removal system.

Hmm, I can't see the FW removal notches. Did you buy the wheel from a company with a customer service number?

Looking closely at the freehweel it appears to have internal threads, and therefore is simply screwed on. But I don't see removal notches, so I suspect that they expect you to work like a third world mechanic, and set a small punch into one of the two notches and tap it off. The cover loosens to the right, so tapping counter clockwise should remove the freewheel as a unit. SS freewheels aren't as tight as typical multispeed freewheels so it may come off fairly easily.

Otherwise find an adjustable pin spanner (or a bike co-op that has one), set it into the two pins, make a bridge with a piece of scrap with a hole in it, and use the axle nut to keep the pin spanner jammed in so it can't jump as you turn it, and turn the freewheel off a few degrees, then remove the nut, and take it off the rest of the way.

Some cheap single freewheels aren't intended to be removed and don't have notches or splines for a remover tool. The only way to remove them is to disassemble the mechanism. A pin tool will unscrew -- probably reverse thread -- the cone, causing the cog to separate from the freewheel body, and allow a pipe wrench or similar nasty tool to grasp the freewheel body and unthread it from the hub. This is generally a destructive process. But are you certain you need to remove the freewheel in the first place? If you can remove the locknut and cone from the fixed cog side, you may be able to slide the whole axle out of the hub leaving the freewheel in place. Check this before destructively removing the freewheel.

Boy, cheap has gotten really cheap. It wouldn't cost more than a couple of Rupees (56 Rupees/USD) to mill a pair of slots into the inner body. I understand saving a couple of Rupees for their home market, but I'd expect whoever spec.d the bike for export to the USA or Europe to be a bit more finicky.

It's not like nobody would ever want to remove a working freewheel, maybe simply to change the size. It reminds me of the old time dealer I bought bikes from as a kid, who had a sign posted talking about "oats that have already been through the horse".

But to the OP, if you only want to service the hub and the freewheel is OK or maybe needs a drop of oil, best to leave it on and work around it. (or through the middle)

You should have no problem removing the cone race on the fixed side and sliding it out the freewheel side, as long as the cone race is accessible under the dust seal. Pry the seal off and see what's under there.

This is exactly what you have, and the best (only?) way to remove it is as JDT describes. You'll have fun counting bearings.

-G

Hi Guys,

Many thanks for all the responses. I think JohnDThompson and others are spot on, in that this is just a cheap bike, so some parts are not designed to be serviced - the bike this hub is on is a Viking Road FX...and this is a cheap bike...but not a "bad" bike.

So basically just undo the locking nut on the fixed gear side, and see if I can slide the whole assembly out with both the fixed gear, and free hub still in place on the wheel? The fixed gear looks like it is notched for a puller, but would there be any reason for me to remove the fixed gear first?

No, there's no reason to remove the fixed cog. If you can slide the axle out after removing the locknut and cone on the fixed side you should be golden.

BTW, the fixed gear side looks like it has a separate lockring (the ring with the notches in it) and these are left-hand threaded threaded while the cog under it has standard right hand threads. The lockring keeps the cog from unthreading under back-pedaling forces. If you ever want to remove/replace the fixed gear cog, keep the lockring's reverse threading in mind.

I'm pretty sure that you do not have to dismantle any of the cogs to take the axle out. The FW and fixed side are both with outer threads and outer parts and none protrude inward past that (like a 11th tooth cog on some some multispeed FW's.

Just loosen the locknut on either side (fixed side is better since you have more clearance, but it really does not matter much, also it's not very controllable which side loosens first unless you hold the axle itself, or the other cone but I disagree with both methods- cones can crack, and axles even grooved or with square ending get mashed so hard that it damages the threads) - pry the rubber seal and undo the cone on that side. Slide the whole axle on the other side and leave it untouched (it will be put again the same way and it's best to have one side really tight a cone jammed into a locknut really tight so it does not unscrew or tighten when you hold counter to adjust and tighten/loosen the other side locknut)

And I can guarantee that "three arrow" FW's have no means of removal (except destructive methods told above), and are really bad quality - those cost around 1-2$ on the market around here - > go figure :rolleyes:

The Park Tool site has a well illustrated article on this type hub. Pay very close attention to the position and orientation of the parts.
You can also remove everything from the non-drive side and pull the axle out the drive side.