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twssas
05-12-2011, 07:54 PM
Had a pedal shear off on a NXT a couple of nights ago during class. Thought I had seen a thread about that in here somewhere recently, but have not been able to find it.

Anyone have an insight on this? No one was hurt, and the bikes are only 6 months old.

Have also had multiple lower bearing bracket failures on these bikes, and star trac is going to replace all on our "fleet".

Really like these bikes, but, gives pause to wonder about the future maintenance needs.

RaffCycles
05-13-2011, 05:48 AM
Star Trac has identified the issue and tied it back to an supplier. They have severed that agreement with that supplier. I'll post a link later once I find their response to this issue.

15inchbrick
05-13-2011, 06:47 AM
Star Trac has identified the issue and tied it back to an supplier. They have severed that agreement with that supplier. I'll post a link later once I find their response to this issue.

Here's the thread

http://www.pedal-on.com/showthread.php?t=9028&highlight=sheared+pedal

Have a great day guys :)

EDIT: and gals ;-)

RaffCycles
05-13-2011, 07:08 AM
Thanks for posting the link.

Here is the post on the community.spinning.com forum. The topic name is "Pedal Shearing Off" and contains an response from Star Trac that was posted by TeamMDA.

http://community.spinning.com/spinningforums/f/114/t/3428.aspx?PageIndex=2

HMBgal
05-13-2011, 10:27 AM
Had a pedal shear off on a NXT a couple of nights ago during class. Thought I had seen a thread about that in here somewhere recently, but have not been able to find it.

Anyone have an insight on this? No one was hurt, and the bikes are only 6 months old.

Have also had multiple lower bearing bracket failures on these bikes, and star trac is going to replace all on our "fleet".

Really like these bikes, but, gives pause to wonder about the future maintenance needs.

And don't even get me started about the loose, wobbly handlebars!

twssas
05-13-2011, 12:41 PM
Thanks for all the information. It is appreciated.
Our NXT's as I mentioned are only about 6 months old and now have had 3 lower bracket bearing failures (which the root cause to me appears to be over torquing at the factory where they were assembled), and now one sheared pedal where the pedal screws into the crank. I personally check all the pedals to insure they are tight at least once a week, so I think we have some type of premature metallurgical failure, possibly due to a material supplier issue, as was stated in a link to spinning.com from both Star Trac and Mad Dogg.

Hopefully, we will try to get Star Trac to replace our pedals at the same time they are replacing all of our lower bearing brackets.

I did purchase the manuals from Studio Cycles, and have found them to be very valuable.

Again, appreciate the responses, and it looks like we have not been the "lone ranger"

zoepup
05-13-2011, 02:38 PM
And don't even get me started about the loose, wobbly handlebars!

All I can say.. they new ones better be fixed. You think they would have fixed it with the first update on the previous ones.

rick316
05-13-2011, 03:28 PM
I would strongly suggest subscribing to Jeff's Youtube channel too as he posts videos on a number of topics and you may well find some extremely useful info on there too.

thejman
05-25-2011, 08:09 AM
never had this but I can imagine it would be an unpleasant experience.

must remember to double check where that first aid kit is

Krissy
07-05-2011, 11:30 PM
I had a pedal break break off in class last week - I'm going to have our equipment service provider check all the pedals on the next visit, as it was quite scary! Luckily, nobody was hurt. We have Lemond Revmasters.

capegirl
08-22-2011, 12:35 PM
I had a pedal break break off in class last week - I'm going to have our equipment service provider check all the pedals on the next visit, as it was quite scary! Luckily, nobody was hurt. We have Lemond Revmasters.
we have Lemond Bikes as well, and have had pedals 'snap' off more than once...scares me to death.

terrors
10-09-2011, 08:07 PM
I have had this happen only once in 10yrs and that happened with a fellow that fancied himself a champion sprinter and had the tension cranked as hard as it would go and he was really torquing it. Watch out for big guys and that want to put lots of tension on :) Also very important that the pedals are tight (snug), no pedaling backwards for sure it loosens the pedals and then the screw part of the spindle is too far outboard from the crank.

Funhog
10-10-2011, 05:03 PM
I have had this happen only once in 10yrs and that happened with a fellow that fancied himself a champion sprinter and had the tension cranked as hard as it would go and he was really torquing it. Watch out for big guys and that want to put lots of tension on :) Also very important that the pedals are tight (snug), no pedaling backwards for sure it loosens the pedals and then the screw part of the spindle is too far outboard from the crank.

I better get to this before Bill does! ;-)

Terrors,
having a pedal shear off is very scary, and you are right, a big powerful guy with a lot of resistance jumping on those pedals to show off a sprint may break one sooner than someone who is lighter. But, just so you know, pedaling backwards does not loosen the pedals. It just doesn't. You can put "pedaling backwards" in the search box above and find tons of threads discussing the subject and see why. Pedaling backwards is not a good idea for other reasons however...

terrors
10-16-2011, 07:45 PM
In terms of pedaling backwards I disagree with you and others, there is just as much information that supports the theory of 'precession' http://en.wikipedia.org/wiki/Precession_(mechanical)

The bottom bracket operates in an opposite manner which presents a different set of problems depending on the threading.

gumbymcgee
02-02-2012, 04:34 PM
I was just posting elsewhere about our NXT pedals falling off... they aren't shearing. We get them "fixed" and 2 rides later off again. Our "bike guy" doing repairs builds road bikes and is not formally trained indoor repairs. He's claiming pedaling backwards doesn't have any effect on the pedals, however, my MadDogg trainer said otherwise. Anybody else have this issue???

Todd S
02-02-2012, 04:49 PM
With quality pedals and crankarms and the pedals properly torqued when installed, it's highly unlikely that pedals could loosen due to pedaling backwards.

That said, with the cheap alloys used on indoor cycle crankarms and pedal spindles and repeated pedal installs, pedaling with a loose pedal, etc., the thread surfaces could wear. With worn threads and inferior metals, precession could be a problem even if the bikes aren't pedaled backwards.

That's just my guess (as a degreed and licensed mechanical engineer).

I'm guessing the reason your bike guy doesn't see this problem on outdoor bikes is that I doubt any outdoor bikes have as cheaply made crankarms and pedals as those typically found on indoor bikes.

gumbymcgee
02-02-2012, 04:56 PM
That's just my guess (as a degreed and licensed mechanical engineer).
I'm guessing the reason your bike guy doesn't see this problem on outdoor bikes is that I doubt any outdoor bikes have as cheaply made crankarms and pedals as those typically found on indoor bikes.

My husband is an (electrical) engineer, and you folks generally are rather smart! I felt the same way about him not really seeing the problem outside. I read somewhere that our bikes have a bottom bracket that prematurely aged (based on when they were manufactured.) We are going to slowly replace that bracket, but I don't know if that has anything to do with the pedal. I think I need to learn some bike mechanics!

zoepup
02-03-2012, 08:22 AM
This may sound silly but maybe some students are removing the pedals to put their own on and not putting the originals back on tight enough. If not torqued properly they will come off. I know from experience on this one.

gumbymcgee
02-13-2012, 05:05 PM
This may sound silly but maybe some students are removing the pedals to put their own on and not putting the originals back on tight enough. If not torqued properly they will come off. I know from experience on this one.
I actually "caught" a member doing this today. And you were right, he did not put the pedals back on tight enough.

bethfit
03-03-2012, 04:25 AM
At one of the gyms I teach at we had a number of occasions where one of the pedals came unthreaded and dropped off (not sheared) and both times it turned out that the threads in the crank arms were also stripped, necessitating expensive repairs. I think it is partly down to the poor quality components used in many indoor bikes, but also a lack of maintenance. I now have a 'contract' with this gym, where I go in once each month and spend a couple of hours doing basic cleaning, lubing, and tightening, and one of the things I always do it check all of the pedals. It only takes a few seconds per bike, but can save a nasty accident (and expense).

Beth

cindy5970
04-14-2012, 01:15 AM
We have been having the same problem at our studio. We have had 5 pedals sheer off within the first 6 months on brand new bikes. Star Trac has replaced them along with new cranks, but I would really love to get to the bottom of this before someone gets hurt.

SSsprocketman
04-26-2012, 11:45 AM
The problem with not tightening the pedal and crank arm properly is most definitely an issue. Here is a link to a few videos that may help with StarTrac NXT. Thanks, SSsprocketman http://www.sportsmith.net/Categories.aspx?Category=9fa19eb8-c28d-4caa-960a-8dbfc490bba3

PartsEtc...
12-16-2012, 01:31 PM
This is an old topic; however, I think most of the pedals on the market are not intended to be used for indoor cycling due to the corroison from heavy sweating and also the usuage and build of indoor cycles (most without free-wheeling). When you purchase pedals from Shimano or other brands, do you get a warning note with them? I have bought pedals with a note "Warning, This pedal is not designed for use on any type of indoor exercise bicycle or equipment"; yet we have no choice, but to go with these pedals...

Depending on usage and how good the bikes and pedals are serviced, the spindle will eventually bend/shear/break.

Can't really compare to the components or build of these indoor cycles to the outdoor bikes... those bikes can cost over $5,000 easily...

Like most people here had said, regular servicing and keep sweat off the bikes are probably the best thing to do.