cyrano138

I'm fixing up a yakota legend, which is a little more modern than most of the bikes I work on, so some of this is new to me. It has a 7sp Shimano hyperglide cassette instead of a free wheel, and the cassette had a considerable amount of play before I removed it. I had hoped it was just a loose lock ring but the lock ring was on there pretty snug. I watched a few videos and it suggested that a spacer might be missing, but there is a spacer both behind the entire assembly and between the removable cog and the rest, which are fused together.

There is a small amount of play in the actual splined part of the hub, but that seems to be a lot less than what I was feeling as I wiggled the cassette.

Where do I start looking for solutions? Do I need bigger spacers? More spacers? Do I need to do something to service the splined part of the hub? Or do I need to just throw the entire wheel in the gulf and start over?

Any help is always appreciated. Thanks!

dedhed

Depending on the hub you can just throw a new freehub on it.
https://www.performancebike.com/shim...hchdgcstqrgqhe

Iride01 

Probably just the bearings need adjusting. Is it this one?

https://si.shimano.com/api/publish/s...0-7S-2389C.pdf

Also if you haven't already..

https://www.sheldonbrown.com/k7.html

cyccommute 

Freehubs don’t generally have the wobble that is typical of freewheels. If the cassette is loose on the freehub body, the likely problem is a spacer. You may need up to 4mm of spacer. Any bike shop should have some spacers around. Get a few widths if you can.

Post pictures yet so that we can see the spacer.

cyrano138

Kind of looks like this might be the solution. See the picture below in the comment about the grooves in the free hub. Still, as someone who's used to being able to throw a $15 freewheel on when the old one wears out, I'm a little annoyed that I have to spend 32 bucks just to replace a piece of this whole mess.
Thanks, I checked the Sheldon brown article before I posted just in case. I watched a few videos too and even the park tool video said that there is a tiny amount of play that's normal in a free hub body. It is very minimal in the freehub body. But it was pretty pronounced when the cassette was on there.
Do you mean the hub bearings? Those are fine. I checked for a play in The hub itself and it's solid.
I didn't have the spacers handy for a photo but they are 1 mm spacers and there are two of them all together. They seem to be in good shape.


I noticed when taking the picture of that the free hub itself has some grooves either worn or cut into it transverse to the splines' direction. I don't know if this is something that is done on purpose or if it's just a sign of wear.

Bill Kapaun

Posting the actual hub model# can be useful to point you to an exploded view of such hub.

cyccommute 

No, I doubt that the freehub is worn enough to cause problems with fit. That’s just not the way that the splines work or wear.

Get a 2 or 3 more of the same thickness. Put on enough so that the lock ring clamps down on the cassette and it doesn’t move.
The cassette can’t spin on the freehub body. The splines prevent it. They can chew into the shoulders of the splines but they don’t spin. You splines look good and don’t seem to have any gouges on the body. It’s likely just a spacer problem. Try that first.

dedhed

That's just the first one that came up in stock in my quick google. You can certainly find them cheaper if you look.

I personally would try spacers on the cassette first as suggested. If you have a coop around you can probably pick up spacers and/or a freehub cheap.

https://www.ebay.com/itm/29312117342...8AAOSwx6ldBAG9

cyrano138

Okay, why do none of the spacers look the same as what's on there? Can I just use any spacer that says it's for Shimano? I'll post a picture of the spacer tomorrow.

cyccommute 

Some times a cassette spacer is used rather than a flat spacer. It doesn’t matter as long as it’s thick enough.

cyrano138

Thanks!

70sSanO

When I look up the bike, it seems the most modern is out of the 90’s.

Can you let us know if the hubs have any model number?

Can you measure the freehub body, (where the cassette is installed), from the end to the cassette stops?

7 speed is 31mm and 8-10 speed is 35mm.

Freehub bodies tend to have a very slight amount of play. I’m less inclined to think the freehub body is bad, but step one is knowing what hub you have first.

John

andrewclaus

Freewheel bikes can bend and even break the rear axle. That stopped happening with the advent of the freehub, which put the drive side bearing nearer the load point at the dropout.

Very few of the many incremental changes in bike design have ended up actually saving the cyclist money, but at least some of them have improved strength and reliability.

You can still get freewheel hubs and replacement freewheels if you want a cheaper, weaker wheel. I'm in the planning process of rebuilding a nice bike from 1982 and am looking at a salvaged set of wheels with a 7-speed freewheel.

Iride01 

Where are the axle bearings? I thinking I should either be seeing them or the dust cap in that picture and I don't see either.

I'm still thinking the wobbly play you saw was the axle bearings not being adjusted correctly. But you were there I wasn't. So I'm just wildly guessing.

MUDCOWS

Honestly looking at the photo I can absolutely guarantee you the freehub body pictured has play on it (just going by the grime scale). If the cassette is sliding along the freehub body then you have an issue with spacing. Before you embark on replacing the freehub body make sure to check rim wear, true, spoke tensions and seized spokes. Might be worth just investing in a new wheel.

cyrano138

I measured it at about 37mm today. I also picked up some spacers of various sizes from the bike shop. Haven't gotten into it yet, but once it's cleaned up I'll reassemble and see what happens.
The axle is definitely fine.

cyrano138

Let me preface by response by saying I can't really back any of this up, and I have somewhat limited experience as a mechanic.

But I would be legitimately shocked if broken axles were in any significant way reduced by moving the force such a small distance. A 9mm steel rod, I'm guessing, would have a breaking (or in this case shearing?) strength well above 20, maybe even 30, kN. Even if it cut the distance of the application of force in half, that's still 10 or 15 kN. That's a lot of force. I could see it on a rigid mountain bike, where the axles are shock loaded routinely, but riding on a relatively smooth surface a 200lb rider just doesn't generate that kind of force.

Were broken wheel axles really that much of a problem? I've never seen it happen and I've certainly never broken one, in spite of the fact that I'm almost 200lbs and have put over 10k miles on a set of wheels more than once in twenty years of riding.

Don't get me wrong, I don't have strong feelings about it. Freewheel, cassette, it makes not much difference in the end and I can't see a tremendous advantage on either side. But I suspect that, as with other pastimes I'm very familiar with (sailing, surfing, tree work climbing), the industry has a way of convincing people they really need a particular upgrade even though the old one worked pretty much as well.

Upgrades are great if you can afford them, but the increased functionality should be somewhat proportionate to the increase in cost. Then again, I think road bike design peaked in the 80s, at least with respect to the functionality to cost ratio.

Thanks for coming to my talk.

70sSanO

If it were me, I’d disassemble the hubs and remove the freehub body.

Loosen the NDS locknut and cone and pull the axle out and the ball bearings.

If it is a Shimano hub, a 10mm allen wrench will remove the freehub body. Soak it in solvent, dry, and re-lube it. I use Phil’s Tenacious Oil.

Clean everything, re-grease, and re-assemble.

It is academic when it comes to maintenance whether it is a freewheel or a freehub. Both have a body that needs periodic cleaning and lubing.

Then you can play with the spacers.

John

andrewclaus

From Sheldon Brown's website:

"Avantages of Freehubs

Due to the location of the bearings in most Shimano Freehubs, the axle is supported closer to the ends. As a result, bent axles are rarely a problem with these hubs."

I volunteer as an amateur mechanic at a non-profit bike shop, where we see a lot of freewheels, and bent/broken axles are not uncommon. It's usually a MTB, but many road bikes see high impact on curbs and other hazards. There's a great reduction in moment arm when the bearing locknut is right against the dropout. As Sheldon Brown goes on to say, it's been a very successful design. See this link: https://www.sheldonbrown.com/k7.html

cyrano138

Would gear oil work?

70sSanO

There has been much discussion that Phil’s is basically bar or gear oil at an exorbitant price. I don’t see an issue.

John

cyrano138

Sweet! Thanks

cyrano138

Fair enough. I've cube across a few axles in my day that were slightly bent. I guess bent is just as bad as broken.

Hondo6

If the freehub measures roughly 37mm in length, I'm fairly sure that means it's an 11-speed freehub. I'm pretty sure you'll thus need two standard spacers if you're going to run a 7-speed cassette.

A 7-speed cassette needs a 4.5mm spacer (or thereabouts - I've seen both 4mm and 4.5mm spacers sold for this purpose) to fit properly on a Shimano-compatible 8/9/10-speed freehub. However, an 11-speed freehub is wider in order to accommodate the wider 11-speed road cassette. Here, a 1.8mm or 1.85 mm spacer is required to use a 8 or 9 speed cassette (and a 1mm as well for a Shimano 10-speed cassette, as I recall; I've seen some sources that say it's not required for SRAM 10-speed cassettes, but I've never used one by SRAM so I can't say for sure that's the case).

If you only had the 4.5mm spacer behind the original 7-speed cassette, that could be the problem. Pretty sure you'll need both the 1.8mm or 1.85 mm and 4.5mm spacers to do that.

https://www.sheldonbrown.com/k7-7.shtml#stay

https://bike.bikegremlin.com/1259/bi...compatibility/

cyccommute 

I can’t disagree more. Start with the spacers. The problem cyrano138 describes is that the cassette is loose. Start with the simple problems before moving on to something more complicated.