Servicing thumbies (with pictures)

[ededwards]

I thought that the following on servicing a Deore 7/8 speed thumbie might be useful (and includes plenty of photos for those that prefer a visual represntation) http://www.allankelly.info/servicingthumbies.html

Would this be any different for a 7/8 speed XT thumbie?

 

[Old Ned]

Very useful Ed, I've got a couple of pairs that worked OK last time I used them but could possibly do with a fettle. Mind you, with things like this, if they still work I don't touch them. Leave well alone is my motto!

 

[Lid]

Wow thats inside those shifters!
Frikin amazing bit of engineering.
Cheers Ed

 

[stevet1]

Nice, will come in useful one day for sure.

 

[Bike Hoarder]

So, looking at the plate with the indexing holes in it, does anyone think it would be possible to put another hole in there and turn their 7/8 shifters into 8/9?

(Ed, i reckon it would be the same, just with another hole on the indexing plate, giving you the famous XT '8th click'.)

 

[Andy R]

So, looking at the plate with the indexing holes in it, does anyone think it would be possible to put another hole in there and turn their 7/8 shifters into 8/9?

(Ed, i reckon it would be the same, just with another hole on the indexing plate, giving you the famous XT '8th click'.)

No, you'd need to make another detent plate altogether. Index spacing is the same for 7 and 8 speed but 9 speed is slightly closer spacing.

 

[neilll]

Nice one.....I saved the whole web page to a memory stick in case it vanishes...

 

[elite504]

Absolutely Neill
but as you guys say, it may be possible to make a 9 sp plate from scratch. I'll add it to the chalk board of jobs to tackle. However, noe of my bikes are 9sp, as its not very retro, and I can't really see the point. 7, 12-28 ratios have been doing me fine for 20 odd years ; )
still worth it just for fun. Can then sell em to you guys ; )

 

[Old Ned]

Just a small query - are XT thumbies basically the same? If so, why were they more expensive?

 

[Bike Hoarder]

Old Ned, as far as i know the only differences are; XT's have a cast alloy clamp, DX's have a steel clamp, and XT's will do 8 speed, where as DX's have no hidden eighth click.

I suppose there might be some variation on internal componentry, lighter, harder wearing etc, but i've not been brave enough to disect any so far.