mwmistak

I seemed to have knocked my SunTour Mountech derailleur out of wack.

When I put the tire back on I am not getting proper tension on the bottom of the chain. And the top pulley runs into the freewheel. (see pic)



I only seem to get the proper tension when I turn the allen bolt. (see pic)

mwmistak

Well I researched this particular derailleur and I found multiple reports calling it an extremely unreliable component. Some took this to the extreme as labeling it a contributing factor to Suntour's demise.

Well as someone who didn't want this derailleur to do to my morning commute what it is accused of doing to Suntour, I borrowed the rear derailleur from my old mountain bike (a Shimano Acera).

It seems to shift like a champ with my friction shifters. There is one problem... The derailleur does appear to rub against the metal disk behind the freewheel when I shift to the largest rear gear.

Is there a way to remove this without having to rebuild the wheel?

gwhunt23

You will want to tighten your low limit screw (usually a philips head marked with a small L.) This way, you can leave the spoke protector on there and the chain will not jump off the largest cog.

ZachS

modern derailleurs + friction shifting = happiness.

i'm not sure I understand what you're describing - are you saying that the derailleur is hitting the disk when it's lined up perfectly with the largest cog? can you take a picture of what this looks like? there should be a way to fix it.

mwmistak

I originally thought that a collision between the disk and the derailleur was preventing the chain from aligning properly with the largest cog.

It turns out I need to ajust the low limit screw as gwhunt23 suggested, as what I'm hearing is the chain attempting to jump the cog.

I guess I was working on this a little too late last night, as I totally misinterpreted this noise...

Thanks