Re: Schwinn Airdyne Failures?
A Muzi
> I've just reached the end of my third Airdyne and am wondering whether
> or not it's worth moving to the fourth.
>
> I have to admit, I don't do a very good job of cleaning and tuning
> them up, but I'm sure there are places where they get more abuse than
> here. This last one had the bottom bracket snap in half on one side.
-snip-
A replacement OPC with bearing assembly is not all that
expensive, usually $15 to $30. Avoid the very cheap ones
with a welded peg for the chainring. Get a forged one (the
peg is one with the crank) and pay a dollar or two more for
a better bearing assembly. Grease bearings liberally.
Schwinn used a quality forged crank on the American made
Airdynes but I haven't serviced an import so I have no idea
about those. At any rate, failure of a forged OPC is a rare
event outside of bikes which are jumped.
Did the crank actually break in two or did a welded peg fail?
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
jwi...@pacifier.com
A Muzi wrote:
> -snip-
>
> A replacement OPC with bearing assembly is not all that
> expensive, usually $15 to $30. Avoid the very cheap ones
> with a welded peg for the chainring. Get a forged one (the
> peg is one with the crank) and pay a dollar or two more for
> a better bearing assembly. Grease bearings liberally.
>
Andy- I think you're a little confused. The Airdyne uses a multi-piece
cottered crank with an extra pair of offset pins connected to the
levers that exercise the user's arms (and the thighbone's connected to
the shinbone...). It's not a traditional one-piece crank by any
stretch. Take a look at
http://www.schwinnfitness.com/products/?function=detail&id=5
To the OP: a quick search found nothing relevant to "Schwinn Airdyne
failure", so I can't tell if what you're experiencing is common or not.
I never had any problems with the Airdynes I sold- but it's been many
years since I worked in a Schwinn bike shop.
jeff
Zippy the Pinhead
left crank; it's most noticeable when using the pedals alone. Using
the hand levers somewhat reduces the clunk but it's still noticeable.
The crank is complicated, there are two cottered cranks coming off the
bottom bracket axle, with a 90 degree separation of the cranks for the
hand lever rod (short) and the pedal. The cotters don't seem loose
and there doesn't seem to be an abnormal amount of play in the bottom
bracket axle (spindle?).
Any ideas? I could pack it up and take it to a Schwinn dealer, but
I'm wondering if I could live with the clunk until April when outdoor
riding is more feasible in my area. Or is the "clunk" an ominous sign
meaning I should get it looked at right away?
Thanks.
A Muzi
>>-snip-
>>A replacement OPC with bearing assembly is not all that
>>expensive, usually $15 to $30. Avoid the very cheap ones
>>with a welded peg for the chainring. Get a forged one (the
>>peg is one with the crank) and pay a dollar or two more for
>>a better bearing assembly. Grease bearings liberally.
jwi...@pacifier.com wrote:
> Andy- I think you're a little confused. The Airdyne uses a multi-piece
> cottered crank with an extra pair of offset pins connected to the
> levers that exercise the user's arms (and the thighbone's connected to
> the shinbone...). It's not a traditional one-piece crank by any
> stretch. Take a look at
> http://www.schwinnfitness.com/products/?function=detail&id=5
>
> To the OP: a quick search found nothing relevant to "Schwinn Airdyne
> failure", so I can't tell if what you're experiencing is common or not.
> I never had any problems with the Airdynes I sold- but it's been many
> years since I worked in a Schwinn bike shop.
Guilty As Charged
When I workeed at a Schwinn house it was Schwinn Ergo not
Airdyne - two very different machines.
Which makes sense as one piece cranks are robust.
(Now we'll hear every case of a cracked OPC , right?)
jwi...@pacifier.com
Cauley Felps wrote:
> Hello,
>
> I've just reached the end of my third Airdyne and am wondering
whether
> or not it's worth moving to the fourth.
>
> I have to admit, I don't do a very good job of cleaning and tuning
> them up, but I'm sure there are places where they get more abuse than
> here. This last one had the bottom bracket snap in half on one side.
> believe this is the same thing that happened to number two. I've got
> that one in storage. All the crank parts usually start wearing out
and
> get to the point where I can make about a quarter rotation of the
> crank before it catches and turns the wheel.
>
> I've got a PDF parts list here somewhere, but the prices were kind of
> ridiculous, like 5 dollars for this washer and 30 dollars for one of
> the cranks.
>
George- as I said to Andy, the Airdyne uses a crank system that is
unique. The Airdyne doesn't use a one-piece crank (OPC, as Andy says),
it uses a multi-part crank to operate the hand levers.
>From your description, I would guess that the cotter pins that connect
the different pieces are wearing out. As soon as one develops a little
play, it will start to wear even more quickly. The key is to check all
of the cotters for play, and tighten them if there is the slightest
sign of looseness. (Sheldon Brown has an excellent article about
cottered cranks: http://www.sheldonbrown.com/cotters.html .)
If the cotter pins get battered past the point of simply tightening
them, they should be replaced. Replacement cotter pins should cost
about a dollar:
http://www.bikepartsusa.com/view.phtml?f_c=null&f_q=cotter+pin&Go.x=24&Go.y=16
With luck, this will keep you from buying new Airdynes every time a
cotter pin fails.
Jeff
Werehatrack
wrote:
[snip]
>Which makes sense as one piece cranks are robust.
>
>(Now we'll hear every case of a cracked OPC , right?)
Well, it does happen, but in my experience the usual point of failure
is right at the pedal eye, and is limited to the cast-iron Ashtabulas.
Over the years I've had two of that type break there, and a third with
a crack in that location was detected in a bike that was getting
donated to a reclamation project recently. I pulled the cracked crank
out and subbed in a used one from Le Carton du Junque before I let it
go. (Swapping it out takes what, fifteen minutes? No reason to leave
it there to cause a problem for somebody.)
On the one hand, I've seen more failures of tapered-BB cranks than
Ashtabulas, but on the other hand, the tapered-BB cranks generally
were getting a lot more use. On the gripping hand, though, mirroring
your experience, I have yet to see a failure of a *forged* one-piece.
Of course, the cast-iron one-piece is by far the more common type;
stuff you see a lot tnds to account for more failures even if it's
pretty decent...and three failures seen in over 30 years of largely
casual usage is not exactly cause for a recall.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.
jwi...@pacifier.com
Cauley Felps wrote:
> Jeff, (or anyone)
>
> Could looseness in the cotter pins or other crank parts cause
failures
> like the ones I've experienced? I'm wondering if my neglecting to
keep
> all that stuff tight on all the bikes has created extra, abnormal
> stress.
>
> The type of "clunking" play that Zippy mentions is something I've
> grown used to (maybe not that extreme). Toward the end of my last
> Airdyne, you could pedal backward and forward for about a third of a
> rotation before the wheel would catch. I thought about replacing
parts
> on that one and had inspected a bunch of them, but the wear was
pretty
> widespread. All the ring inserts in the "pedal to arm" brackets had
> play and most of the crank parts were at the point where they
couldn't
> be tightened enough to compensate for the wear inside the crank arms.
>
Hmmm... the more I think about it, the less likely I think it's the
cotter pins. Loose cotters would show up as the crank arms not moving
with one another- what you're describing sounds more like one of the
drive sprockets has come loose from its spindle. With the Airdyne's
two-stage chain drive, it's tough to tell without removing all the
guards and cover plates and watching while the cranks are turned. There
might be something that's coming loose that you could tighten up- but I
don't know *what* without actually diving in, dissassembling, and
inspecting things. It sounds like yo've done a pretty good job of that
already.
> Is it possible that this bottom bracket (axle) part is still the same
> standard type as any other common three piece cranks?
>
I don't think so. Without a picture I can't tell. Didn't you say you
had found a PDF parts list? Where did you find it?
> I'm still trying to figure out what to do. I feel like a fool to keep
> buying these things if there's something better or more durable out
> there. It also seems that there are a bunch of them out there which
> probably got used for a month after new years and then end up in a
> garage or something (that's where this last one came from), or as a
> once in a while substitute for real bikes during bad weather. That
may
> account for why there aren't more worn out ones around, but the
> fitness center Airdynes would still be getting burned up. (?)
>
> -Thanks!
> George
I don't think you're being foolish if you're buying them *cheap*. I'd
bet that there's plenty of low-mileage Airdynes out there that were
"New Year's resolutions" and are now gathering dust in the garage.
Possible strategy: find a fitness center ("health club", "gym", etc.)
that has an Airdyne or two. Ask a manager who services the machines-
and then track them down and ask about the Airdynes. I'll bet you'll
get a lot more good information from them than from my (educated)
guesswork.
Jeff