New Rear Dérailleur

[wesfoster]

On a climb yesterday my rear dérailleur snapped just as I was changing down. It's an old one, and one that I was going to replace anyway but in more of a job lot of parts though now I'll have to get that first then the rest later.

I use down tube shifters, and a six speed rear wheel (temporarily until I have a bit more money at the end of the month) along with a single 53T.
Would it be possible to run a shimano 105 5700 with the downtime shifters and six speed. I'm not after perfect, just good enough until I get the new wheels on and new cassette.

Cheers

 

[mjr]

I think so, as long as you set the limit screws carefully and your rear sprockets aren't bigger than its capacity. Someone who's done it may be along in a bit

 

[winjim]

Derailleur pull ratios are the same, it just depends how well the wide 6sp chain will run through the narrow 10sp mech.

 

[mjr]

Good point but 10 speed chain is about 6mm width so shouldn't fall into the 3.5mm spacing of a six speed. I'm not sure about the chainrings though.

 

[wesfoster]

Thanks for the help. Yeah thought it would be alright, but always best to check with someone who knows a bit more haha, only temporary anyway so should be alright for a month or so until a new pair of wheels/cassette is on.

 

[mjr]

I think we've said we think it will but we're not 100% sure. If I were you, I'd get the ruler out and check the widths of the gap in the rear derailleur to see if six-speed chain will fit through, or check the gap between the chainrings to see if ten-speed chain could fall into the gap. Of the two, I think six-speed chain jammed in the RD would be worse than ten-speed chain falling between the chainrings.