Originally Posted by
David_Sweden
They looked through the stock for 5 minutes for me while I was watching and said my gear was antique because it missed some "mounting hole that all new Shimano gears use".
Your stuff is a bit old, but derailers with the same mounting method are still being made. Even by Shimano.
Either you misunderstood, or the staff don't know what they're talking about.
Originally Posted by
David_Sweden
So I guess I can use the "Tourney RD-TY500-SGS" without any adapter needed then?
You should be able to use just about any derailer that has an U-shaped slot instead of a (fairly big) screw at the top.
There are finer points like "maximum capacity" and chain wrap, but the big thing is slot vs screw.
Originally Posted by
David_Sweden
Looking for 7-gear "hanger mount" real derailleurs I find
Shimano Tourney RD-TY300, and also
Tourney RD-TX35, would those work?
- bikester.se/shimano-tourney-rd-ty300-bakvaexel-med-adapter-svart-488560.html
- staffanstorpscykel.se/bak-vaxlar/1547-bakvaxel-tourney-tx-30-for-6-7-del-med-fastora-shimano-4524667432562.html
Those would work.
As would this:
Bakväxel Shimano Tourney - Cykeltillbehör Bakväxel, cykel - Biltema
Originally Posted by
David_Sweden
I do know how to adjust chain length.
The picture says otherwise.
Chains should be sized to allow the gears to be in the big-big combination w/o breaking the derailer.
Yours doesn't look like it'd survive that.
Originally Posted by
David_Sweden
This one is mounted by a shop though
Then the shop got it wrong, see above.
Originally Posted by
David_Sweden
.... and has worked for many years...
Either you've been very lucky, or you are very good at keeping track of your shifting pattern.
Originally Posted by
David_Sweden
... both gears are in mid position so I wouldn't think gear is stretched much in pic.
It is. It should only be that stretched in the big-big combination. And even for that it'd be dangerously tight.
Originally Posted by
David_Sweden
By pulley I guess you mean cogwheel?
The small wheels the chain run on in the rear derailer are called derailer pulleys. There's the guide pulley (top) and the tension pulley (bottom).
Originally Posted by
David_Sweden
Shop said cogwheels can't be bought...
Shop is wrong:
Should fit for your derailer. separate pulleys can certainly be bought.
Originally Posted by
David_Sweden
...that entire gear is exchanged, and sounds reasonable...
Admittedly, at the Tourney level of components, you're not saving much by replacing pulleys-only.
And you'll get some good from the whole derailer being new.
Originally Posted by
David_Sweden
... since gear costs less that the cost of time to do the job.
WRT time, I don't think it's true. It's faster to split the derailer open to thread the chain through than it is to split the chain. And the extra time it'd take to replace both pulleys when you already have the derailer open is 2 minutes tops.
For you, it's not really applicable, as you really should get a longer chain too.
And since you're asking here - instead of leaving the bike at a shop, I assume you're looking to do this yourself.
If you do, the issue of what the time costs doesn't apply to you as to a shop.