help with rear derailer

[Patch T]

Hi Bunch,

Hoping you could help me work through throuble-shooting a friction shifting issue on a rear derailer. I have a feeling it's actually a much simpler issue than I think, and that I may already know the problem. But looking for advice anyhow.

PROBLEM: 

-- rear derailer won't shift into highest gear on it's own 

-- but it does when I apply forward motion with moderate pressure with my right foot at about 2 to 3 c'clock position 

-- all other gears shift fine, if not wonderfully

CAVEAT: 

-- I'm using vintage parts that may not play well. But I think they could? All but one part are in great condition. So there's that.

DRIVETRAIN: 

-- rear derailer: Suntour Cyclone GT long cage  the High limit screw is maxed out

-- front der: Suntour Cyclone

-- have tried both 8 spd and 9 spd 11-32/36 cassettes with same issue, although 8 speed is slightly better

-- White Ind M15 shimano body hub, with correct spacers

-- yes, fresh chain

-- Rene Herse double 44/28

-- 113mm bottom brackett

-- vintage suntour bar-cons (this is the only vintage item that is not in near-perfect condition, in my amateur opinion)

-- recently changed all cable and housing

ALSO IMPORTANT: the same bike has experienced great index shifting with the following:

-- White Industries ENO crank with 42 tooth chainring

-- same 113mm bottom brackett

-- SRAM Rival road brake/shifters

-- SRAM Rival rear derailer

-- SRAM cassette 11spd, 11-42 

THOUGHTS:

-- this is a chainline issue; the WI crank has a wider Q that the Rene Herse, so derailer can move chain outside easier?

-- If the above is true, is the only solution a BB with longer spindles?

-- I'm being overly optimistic with the actual abilities of the Suntour Cyclone and should give up. Even though it easily wraps the lower gears.

-- the derailer is in fact bent and I can't tell with my naked eye

Thanks everyone!

Patch

BK/NY

[Deacon Patrick]

I am quickly outclassed by derailures, but my first thought was to adjust cable length. Kind of an "is it plugged in" suggestion, but you did ask for simple. Grin.

With abandon,

Patrick

[Bill Schairer]

I have several Cyclone GT’s and have had this same problem with one of them.  I think there are two different mounting styles.  The one I had trouble with I solved by mounting it with a washer (don’t know what else to call it) type thing between derailleur and dropout pushing the derailleur outbound.  This did NOT cause issues shifting all the way in to biggest cog on a 9 speed cassette.

Bill S

[Bill Schairer]

Let me try again with the photo

[Bill Schairer]

I think this style may have been designed for a claw mount rather than a direct mount?  Sorry I didn’t get this all in one post.

Bill S

[Garth]

Patch,

Without the chain, cable installed, does the shifter have enough travel to cover the cassette ?

Now try it with the cable, is the travel the same ?

[Patch T]

Whelp, a super thin, maybe 1 or 2mm washer I dug out of the ol' washer bin and set between the derailer and hanger did the trick as Bill explained.

So very thin, but now I have a smooth full range over the 9 speed 11-32. Slides into the 11 tooth easily. Still enough thread engaged, too.

Thanks Bill!

Patrick - I did re-check the chain length first, and it was good.

Garth - I had checked the range w/o chain before mounting and it was good.

Thanks everyone!

Patch

BK/NY