Freewheel "wobble" (for lack of a better term)
 

this past winter i had some velo orange grand cru high flange hubs built up.

I installed a cheap freewheel on them and noticed that the freewheel wobbled. This is hard to describe: looking down on the bike from above, if I spin the wheel there is a discernible wobble in the freewheel. That is: even when the cogs are not turning they move in and out in relation to the centerline of the bike/wheel. I can't imagine this is good for the chain, the cogs, or pedalling efficiency.

I took it to the LBS that built the wheels and they saw it immediately and told me the freewheel was bad.

So I ordered an expensive, IRD freewheel. Which is beautiful. I didn't even bother to look at first to see if it wobbled. But I was just changing the brakes and indeed the thing wobbles just like the other one.

Is this normal?

Other data: the rim is true and about as straight as a wheel can get.

My suspicion is that there is a flaw in the hub -- like the threads where the freewheel mount is not perfectly in line with the axle.

Thoughts?

DING DING DING. That's the exact reason and it's perfectly normal.

I can't recall ever seeing a freewheel that didn't wobble, though I'm sure somewhere one must exist, if purely by accident.

Wait: so a flaw is normal?

I'm rather surprise that they wobble like they do. Why would that be the case?

Maybe you could spend a few $mil and design one that doesn't.
It's called manufacturing tolerances and work fine for us humans.

The machine that presses/machines the freewheel threads onto the hub is different than the machine that presses/machines the races? Anytime you remove the hub from its mounting point it'll be hard to mount it perfectly centered the next time around.

I'm happy to live with it. It just seems odd given how precise so much gear seems to be.

Wobble or not, the hubs look nice...and that's what matters, or so I tell my kids.

They are actually meant to wobble like that. It is done on purpose and was made that way before there were ramps for shifting, and the wobble helps the cogs pick up the chain when you shift

:lol:

Find a new shop.

but for real, if it's not wobbling so bad that your crank pulsates, it won't affect your shifting at all. I wouldn't worry about it too much.

also - who is still building bikes with freewheels?

Hey man, I still dig 27" wheelsets, most of which come with a freewheel hub on the rear wheel...

http://bikeserver.weebly.com/uploads...1436185517.png

A lot of department store bicycles still have & speed freewheels even though the spacing is 135mm because the frame is a wannabe MTB. I wonder how many axles on those bikes break?

Cheers

I think a better term is "nutation". https://en.wikipedia.org/wiki/Nutation

You've correctly identified the issue: the freewheel body is not perfectly coaxial with the hub. But it's not a problem. The only time the wobble occurs is when you're coasting. When you're pedaling there is no wobble. So, if it bothers you, just make sure you never coast. :)

It can wobble when pedaling because the cogs are not generally parallel with the wheel, though there may be one or two relative phases between the freewheel and wheel where they are (or are very close to) parallel if the wobble of the freewheel with respect to the wheel passes through parallel.

I've been out of biking for a long time. What took the place of the freewheel? Are you saying that current bikes don't have coasting capability with the rear cassette?

Freewheels have been largely replaced by "freehubs," in which the ratchet mechanism is incorporated into the hub body rather than cog cluster. This allows the drive side hub bearing to be located further outboard than is possible with a freewheel; an important improvement as more and more cogs get added to the rear cluster. Axle breakage occurs with freewheel hubs because of the distance between the drive side bearing and dropout creates a lever that flexes the axle, eventually fatiguing it. The problem is exacerbated as more cogs are added, increasing this lever arm. That's why you seldom find freewheels with more than 7 cogs, and never with the 10 or 11 cogs than have become popular lately.

I'm Still fine with My 6 speed freewheels* .. (Though the IGH bikes are my daily Riders)

Indexing is fussier with hanger alignment and planar wobble . also where freehubs have become standard.


*Though I invested in a much better Hub, Phil Wood. Axle is super strong.

Uh - how does it ride? It's a functional sport.

If it rides OK and doesn't throw the chain and shifts all right, that's what a bicycle is supposed to do. If it does one of those bad things, that's when to start worrying not before.

I believe that this is correct.......

Incorrect.

No two cylinders can be perfectly round, or concentric, or co-axial.

That the wobble is intended to aid shifting may be incorrect in and of itself, but the fact that I believe it to be correct is not...........

In these days of CNC machining accuracy, I find it difficult to believe that such machining errors exist, especially from a company such as Velo Orange.

Again, my opinion.................

Lotsa bikes in the third world (China, India, Walmart) have freewheels.