Newbie - BSA Prima/Shimano 105 build help

[moose]

Hi,

I'm upgrading my childhood BSA Prima with 105 10sp components. I've indexed the rear frame to fit the wheel and now I'm looking to mount the rear mech.

The Prima frame doesn't have an integral mech hanger so I'm looking for advice. Are they a standard fitment or will I need something specific?

Thanks.

 

[NeilM]

Re:

The thread in the rear derailleur dropout is universal on modern mechs, so you are OK there.

What you need to find is a hanger which is held in place by the back wheel axle. I can't find exactly what you need, but it will most likely be here somewhere.

Linky: http://www.sjscycles.co.uk/replacement- ... pt669_pg1/

 

[Midlife]

You need a mech hanger something like this from Amazon.

http://www.amazon.co.uk/Shimano-Compati ... B00QL1Q114

Other vendors and makes available.

Shaun

 

[NeilM]

Re:

See, there's always some smart arse who knows exactly what's required....... thank goodness.

 

[moose]

Re:

Thanks both for your help.

The problem as I see it is that I have no hole through which to bolt to prevent the hanger rotating.



The original hanger was fixed in place by a clamp nut and bolt around the outside of the frame. With the 10sp cassette there is now no room for the captive nut. I think I need to either spread the frame wider and fit a spacer to allow use of the nut, drill and tap the frame to allow me to bolt directly to the frame or get a hanger that somehow doesn't allow rotation.

Again, any suggestions gratefully received.

 

[Midlife]

The dropout looks somewhat spread open?

The mech hanger bolts to the dropout with a special nut / bolt that engages the dropout slot itself, The mech hanger usually has two raised studs / rails on the back which lock into the dropout slot to prevent rotation. You could always drill a small hole in the dropout and use a self tapper to hold the mech hanger in place. The nut holding the wheel in place actually does most to keep the mech hanger there.

Shaun

 

[moose]

Many thanks Shaun. I've ordered a hanger and I'll make it fit. It's nice to just double check that I'm on the right track with people who know sometimes.

I hadn't ridden a road bike for years - back then they were called racers - but got on it a few months ago and loved it. It's not the best frame but it's 531 tubing, it's straight and it's mine. I'm enjoying riding it and enjoying fiddling with the newer kit.

Cheers for now.