8 speed cassette with 7 speed shifters

[Blue Hills]

I have heard (or imagined/dreamt/been sniffing too much GT85?) rumblings that Shimano indexed flat bar shifters actually have an extra click, so that a 7 speed shifter would actually shift an 8 speed cassette as long as you adjust the limit screw?

Any truth in this?

Reason I ask is I have an old 7 speed 1997 vintage hybrid/part-time tourer with combined shifters/canti brake levers.

I'm perfectly happy with the cantis and I like the levers, even though they were maybe pretty low-end in their time - the levers on my posh new tourer look cheapish/too shiny in comparison with their nice smooth/aged patina.

So if this could be done it would reduce fettling, all could stay the same and I could use a cassette with a bigger rear cog for getting up hills fully loaded.

I should stress that I have recently changed the rear mech to a modern one and it can definitely handle the extra chain length I'd need.

 

[mcshroom]

I don't know if there's any truth to the rumour or not, but you can get pretty low gears on a 7sp

http://www.chainreactioncycles.com/Models.aspx?ModelID=6387

 

[fossyant]

Don't know about the extra click, but 7 speed shifters work well with a 8 speed cassette, with the 8th sprocket removed. The recommended spacing is 3.1mm. 8 speed is 3mm. I run two 7 speed bikes using 8 speed spacers - no issues.

 

[cyberknight]

Don't know about the extra click, but 7 speed shifters work well with a 8 speed cassette, with the 8th sprocket removed. The recommended spacing is 3.1mm. 8 speed is 3mm. I run two 7 speed bikes using 8 speed spacers - no issues.

Indeed, my current hack runs this set up with no problems using the same cassette set up with an 8 speed shifter with the limit screws stopping the fastest extra gear, i figured it was safer to have the chain fall off on the chain stay rather than the spokes if this failed although the limit screws hold it in so far........

 

[Blue Hills]

I don't know if there's any truth to the rumour or not, but you can get pretty low gears on a 7sp

http://www.chainreactioncycles.com/Models.aspx?ModelID=6387

I know that cassette - it's good - have used it including on a 21 Dahon Speed Pro, but due to an oddity with my frame the small 12 tooth ring seems to end up with a bit of chain clash with the frame - not an issue if I have a chain on an 11 tooth small cog.

As for the other suggestions I suppose I could do that (stick to 7 speed shifters with 8-speed cassette) but I've pretty much decided to go to 8 speed [yes I know, I'm just a slave to fashion ] and I don't really want to lose the "fast" cog - just trying to do it in the simplest way. Also I like keeping as much of the original stuff as possible.

Am starting to get the idea that this extra click thing may be something of a myth.

 

[Blue Hills]

PS mcmushroom - how is egremont - I remember an ancient Mike Harding tape/record where he described it as the "gateway to oblivion" - probably just a throway line - trust you'll still give me helpful friendly advice - all the best.

 

[cyberknight]

check your frame spacing to see if you can run 8 speed as the hub could be wider.....
http://sheldonbrown.com/cribsheet-spacing.html

 

[Blue Hills]

Ta cybernight but not sure I understand the problem - it's a 9-speed wheel build (damn the need for usseles dishing I don't need) - spacer on to allow 7 speed. So there will be no problem with 8?

 

[cyberknight]

Ta cybernight but not sure I understand the problem - it's a 9-speed wheel build (damn the need for usseles dishing I don't need) - spacer on to allow 7 speed. So there will be no problem with 8?

because i missed that bit,ignore me

 

[Blue Hills]

no probs cybernight - I sometimes read things too quickly.

and I've just been told elsewhere that the extra click thing isn't true - I thought I'd heard it before but I have also misunderstood something more recently.

getting hot out there isn't it