Can 7sp XT SL-M732 Thumbies shift 8 gears?

[Dr Dremel]

Really dont know what this talk about drilling an extra hole is about? Have you not disassembled one? There is an extra hole, it was just not intended for an extra gear, it´s for the spring in the lever to hook into. That´s where the "extra click" is coming from. Yes it´s not 100% spaced correctly and because the end of the spring is poking through not 100% as deep as the other dimples, and it´s just on one side of the clicky ring, but if it´s good enough for Kona to spec thumbies with an XTR rear hub as OEM, then it´s good enough for me.

For a more affirmative click you can dremel an extra dimple on the other side, but it´s not strictly necessary IMHO (I never bothered) as the click is on the end of the travel of the lever anyway.

For completeness: Same goes for 6sp thumbies with 7sp cassettes. The play in the upper pulley of Shimano RDs will take care of the slight difference in spacing.

 

[Tootyred]

Yes.. there is a hole....but its not for that....its a hole not a indent, so the bearing goes right in, its also not spaced correctly ( see the others spacing) and its larger.

My assumption is it there to deter you from over-driving the shifter any further round....to stop you damaging it.

But yes, it will serve as an 8th, all be it inaccurate gear......but then you can also use a screwdriver as a chisel.

 

[Tootyred]

Just for reference here is the inside a a switchable suntour thumbie i rebuilt......8 indents.....8 speed.

The last hole is blanked off when the selector is switched from 8 to 7 speeds.

 

[Rank_21]

Really dont know what this talk about drilling an extra hole is about? Have you not disassembled one? There is an extra hole, it was just not intended for an extra gear, it´s for the spring in the lever to hook into. That´s where the "extra click" is coming from. Yes it´s not 100% spaced correctly and because the end of the spring is poking through not 100% as deep as the other dimples, and it´s just on one side of the clicky ring, but if it´s good enough for Kona to spec thumbies with an XTR rear hub as OEM, then it´s good enough for me.

For a more affirmative click you can dremel an extra dimple on the other side, but it´s not strictly necessary IMHO (I never bothered) as the click is on the end of the travel of the lever anyway.

For completeness: Same goes for 6sp thumbies with 7sp cassettes. The play in the upper pulley of Shimano RDs will take care of the slight difference in spacing.

View attachment 643671

Yes that‘s exactly where I’m thinking. Yes that click is very important (it somehow makes me happy). Now, the hole, that also acts as the holder for the return spring. Since the spring is tensioned the other way, lengthening that hole so that the bearing reaches further creating an even spacing. Then dremel dimple other side. Think I got spare parts of these anyway, so could F it up and not worry.
EDIT. Looks like there’s gonna be an issue. The spring reaches to the top. Maybe filing down the spring too.

 

[hamster]

I have always wanted to take an 8s downtube shifter apart and swap the indexing ring over - or at least see if it is interchangeable. I bet it is.

I also ran for years with bar-end shifters on the Pauls mounts (also cheaper equivalents available from SJS Cycles) which obviously work fine.

 

[Prodigal Son]

The floating pulleys on shimano derrailleurs take care of the difference in spacing.

 

[hamster]

The floating pulleys on shimano derrailleurs take care of the difference in spacing.

Indeed, but they were designed to take up the problems caused by cables sticking and getting mucky. These mixed 7/8 solutions are fine in the dry but (in my experience) get tetchy over a UK winter. A good quality sealed cable system is necessary to keep it running OK.
There again after getting fed up with mine I just switched to friction.

 

[Prodigal Son]

Indeed, but they were designed to take up the problems caused by cables sticking and getting mucky. These mixed 7/8 solutions are fine in the dry but (in my experience) get tetchy over a UK winter. A good quality sealed cable system is necessary to keep it running OK.
There again after getting fed up with mine I just switched to friction.

Did you ever check the alignment of the derrailleur hanger on your frame? Friction shifting is cool.

 

[hamster]

Yes, it's totally fine, setup from clean it runs quietly.
Shifting starts OK with new cables and outers but deteriorates with time as cabling gets mucky. Often pushing on the shifter after the shift a little helps quieten things. Switching to friction means you can tweak the mech a bit more, then it's silent so definitely alignment is not a problem.

The 1.0mm of float takes up the accumulated 0.6mm-ish of error at the edges (top and bottom). But that means that there is only 0.4mm left for cable stickyness etc. - hence why it's tetchy.