Bicycle Mechanics - Which front mech ?
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I am currently re-building an old Raleigh Pioneer 120 frame into a city bike, i.e for commuting etc, as the entire drive train was toast when I rescued it I have started again from scratch and the last piece of kit I need to consider is the front derailleur.
I have rebuilt using a 53/39 double crank set with a 6 speed 14/28 Shimano freewheel on the rear running through a Shimano RD TX31 derailleur with grip shifts on straight bars for comfort. I have road tested the set-up and I am happy with the ratios as they are as it makes for an easy ride.
What front derailleur would the members of this forum suggest? It needs to be suitable for bottom pull control and 28.6mm band on fitment, it will be run through a friction shift twist grip, I would like it to be Shimano if possible to complete the set.
10-23-10, 09:42 AM
53/39 means that you need a road front derailleur. They'll all be bottom pull so that's a non-issue. A friction shift Grip Shifter will work with anything so you're OK there too.
I'd just use whatever Shimano derailleur I could find that fits the seat tube. I like to use one that generally matches the component quality level of the rest of the bike.
10-23-10, 11:02 AM
I didn't know they ever made a friction grip shifter. What is the brand?
10-23-10, 12:44 PM
i'm thinking you'll be better served with an older front derailer, as the 10-speed parallelograms can be too narrow, and cause some rubbing with 8speed chain. If you havent actually tossed out the original front derailer(mech), it is probably salvageable. If not, get a tiagra or a sora, 28.6 clamp.
As far as friction grip shifters, these are more accurately referred to as "ratcheting" than as friction. Basically, these will "click click click", but the clicks do not coincide with an indexed position. They're quite adaptable to many different drivetrains.
Thanks everybody for the replies, I now know what I am looking for. With regards to the friction shift twist grip I mentioned it is a "no name" I purchased of the Bay and as surreal suggests it is the "click click click", type which is perfect for what I need. The old front mech was totally trashed, all the pivots were worn and the cage bent.
Thanks again for the replies.
OK guys an update, after considering the advice offered I went looking for a front derailer I ended up with a brand new Campagnola unit sold as a "9 speed" for just 10 pounds sterling. Its a beutiful piece of kit and looks very well made.
Fitted it last weekend and after a bit of adjustment it works great and handles the jump from the 39 tooth to the 53 tooth rings no problem..... The only problem now is I wished I'd got a Campy rear mech as well .....
11-13-10, 07:56 PM
you may find one for cheap later, and swap. in the meantime, just enjoy the ride.
congrats on the successful build!
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