rear sprocket teeth

[bill in pa]

While cleaning up my bike I noticed the two smallest gears on the back wheel, it has 7, have angled sprocket teeth, they're bent outward. Is this normal? I never really noticed it! The other 5 all have straight, in line teeth. Thanks.
Bill in Pa

 

[alienator]

While cleaning up my bike I noticed the two smallest gears on the back wheel, it has 7, have angled sprocket teeth, they're bent outward. Is this normal? I never really noticed it! The other 5 all have straight, in line teeth. Thanks.
Bill in Pa

Are they bent or twisted? Twisted is ok. Bent is not.

 

[wooliferkins]

Bill,
No. Looks like you will need a new cassette or freewheel depending on your 7 speed. Annoyingly when the world was 7 speed a new invention the cassette appeared. Prior to this the sprockets at the back had the freewheel as an integral assembly and you screwed the whole malarkey on and off. Then the modern cassette appeared, the freewheel became part of the hub (freehub) and the sprockets slid on and off a splined shaft. Your LBS will be able to spot the difference as the two are not interchangeable.

 

[swampy1970]

The cassette came around before that. Dura Ace AX was a 6 speed group that had a freehub/cassette and was available in the early 80s (82?). The earlier Dura Ace groups might have even offered 5 speed with the freehub technology... but I'm not old enough to remember those...

 

[wooliferkins]

The cassette came around before that. Dura Ace AX was a 6 speed group that had a freehub/cassette and was available in the early 80s (82?). The earlier Dura Ace groups might have even offered 5 speed with the freehub technology... but I'm not old enough to remember those...

AX was the first but the technology didn't trickle down to mere mortals until 7 speed hence the PITA 7 speed hassle of freewheel/ freehub and different OLN spacings involved.

 

[TKOS]

If you change out the gears also get a new chain. It isn't expensive and well worth it.