Freewheel Play !

[atlantis]

Hi !

My Trek 7.1 fx has been used for about 1 1/2 years, and I checked the chain had stretched a little, checked it with a xtools gauge the .75 marker was almost in. On close observation, I shook the freewheel to and fro with my hand and felt some play. I felt the play, is a little above normal. I checked other bikes and it was not the same. Its a 7 speed freewheel .

Is this a matter of concern ? Or am I just over reacting ?

 

[alfeng]

If your bike is of a recent vintage, then it probably does NOT have a Freewheel ...

The rear hub probably has a "compact" Freehub body onto which a Cassette is sleeved ... there may be SOME motion in the Freehub mechanism relative to the hub, but not too much.

What you want to check is the LOCKRING which holds the Cogs of the Cassette on the Freehub body ...

You do NOT want the lockring to loosen too much (it should really be snug) because if it does loosen beyond a certain point then the smallest cog will spin freely (i.e., NOT be engaged) and may cause your foot to slip which may cause you to fall ... so, it IS potentially something to be concerned about.

Check www.sheldonbrown.com for the difference between a Freewheel & a Cassette (plus other useful information) ... the lockring will look like a flat disc (because that is what it is) which will have a notched inner circumference into which the appropriate tool fits in.

 

[qdc15]

In which direction is the freewheel moving? Side to side, up and down or rotational?

Quote:
Originally Posted by alfeng .

If your bike is of a recent vintage, then it probably does NOT have a Freewheel ...

I used to think this was true, but in fact lower priced bikes are now being speced with freewheels.

 

[CAMPYBOB]

From what I could find, the 2010 7.1FX used a cassette: http://www.evanscycles.com/products/trek/71-fx-2010-hybrid-bike-ec016501

The 2012 7.1FX uses a cassette: http://www.trekbikes.com/us/en/bikes/town/fitness/fx/7_1_fx/#/us/en/model/details?url=us/en/bikes/town/fitness/fx/7_1_fx

As Alf suggested, check the lock ring to make sure it is secure. If you do not have a lock ring tool, your local shop will sell you one or tighten it to spec for you.

A small amount of shake/play/slop in the cassette hub bearings is normal with wear. The bearings or bushing can sometimes be adjusted, sometimes it is replaceable/rebuildable. Your local shop can assess the play situation and advise you of your options while they inspect your lock ring.

If your shifting is on the money and there are no weird noises coming from the gears or cassette hub, it's probably nothing serious. Again, as Alf stated, do look at things if for no other reason than the safety issue involved. Since you are about due for a chain replacement, an overall service/repack of the driveline and wheels is probably in order.

 

[oldbobcat]

Bob's right, older 7.1 FXs use 7-speed freewheels, and a little play is OK. I'll have to look more closely at the 2012s. And if you watch them doing their thing (coasting) they will appear to float. That's OK, too. The gaps between cogs are pretty wide so indexing isn't all that touchy.

If your chain's just starting to show around 0.75 mm of wear and you replace it within, say, the next 300 miles, it's extremely unlikely that the new chain will skip over the cogs.

Keep a clean drivetrain, replace chains before they go too far and keep them lightly lubed, and you will get long mileage from your freewheel and chain rings.

 

[atlantis]

Thanks for the replies !

@ alfeng -Yes it is a freewheel, since I have removed it for regreasing the rear hub. Unfortunate but true, Schwinn, Gt, and Trek base models are still using the freewheel rather than the cassette which seems to be the standard norm for all new bikes.

@ - qdc 15 -Well the play is side to side and this is by feel, noticed this when i was removing the freewheel from the hub.

@compybob - I have the same 2010 Trek which you have mentioned and it is a 14-34 freewheel, you would be surprised that even the spokes are not stainless steel, they are just plain black coated steel. Lol ! even the Bottom Bracket is a vp instead of a Shimano.

@oldbobcat - I do not mind the float during coasting, I feel its quite common in a lot of freewheels. But just the side to side play seems a tad more than normal.

Another question which I had was I am aware a stretched chain will eat up the cassette/ freewheel eventually, does it have the same damaging effect to the crank as well ?

 

[CAMPYBOB]

A stretched chain will eventually wear chainring teeth. The soft aluminum teeth will wear more slowly with an unstretched chain, but still wear with even a new, clean, lubricated chain. Aluminum is soft and the hard anodization of the higher end chainrings wears away fairly quickly. The larger number of teeth engaged with the chain spread the stress over more teeth than the steel (or titanium in some cases) cassette teeth and this increases the wear index considerably. That said, I replaced a 53 tooth ring last year after it served 5 years at 5K-7K miles per season. And it might have gone another couple thousand miles without a problem. Generally, if the teeth are starting to hook noticably it is time to replace the chainring. If shifting quality starts to degrade, it may be time to replace the chainring. OP, I'm guessing yours have many, many miles left in them.

 

[oldbobcat]

And, yeah, if the sideways play in the freewheel is loose enough to affect your pedaling, your shop can get a replacement for about $20.

 

[atlantis]

Thank you for your replies !