XT front mech bottom swing for P7?

[Simbob7]

I am looking for a front mech for my 1996 P7. I'd like to go all XT kit and have spec of M739. But on trying my LX it appears I need a bottom swing (top pull) as the seat tube ovulates at near the BB and a top swing bracket won't fit.

Can anyone confirm my diagnosis, and if so advise if a top pull, bottom swing 31.8mm XT mech exists in M739? If not is there something close earlier (e.g. M735 or M737) or later (e.g. M750/751 o M760/761)?

Or is there are cunning work around for a topswing?

 

[fingers]

Both my P7's run top swing/low clamp front mechs... I have used m739, m960 and some LX ones too...

 

[Simbob7]

Thanks Fingers. Ow do you it? My 31.8mm tube is 'squashed' to 30.4 min and 33.6 max and I can't see how to get a clamp to fit neatly and securely to take the tension.

 

[fingers]

I dont know - It just seems to fit, I think it bends the clamp slightly, as when I took a front mech off the P7 to put it on the GT, it needed a little 'cold working'... !

 

[the great roberto]

Are the bottom swing M739 front mechs not M738's ?

 

[Simbob7]

Front mech

hmmm

http://www.mombat.org/Shimano.htm says 'Front derailleur: FD-M739 (top swing) or FD-M738 for compact chain rings, Advanced Light Action' but I don't what compact chain rings are

You might be right. http://weightweenies.starbike.com/listings/components.php?type=frontderailleurs seems to suggest the 738 is downswing (DS) as does http://www.bikepro.com/products/shimano_tables/2005_tables/shim_fderA_05.html if that is what 'conventional link' means. But then I look at http://cgi.ebay.co.uk/Shimano-xt-fr...temQQimsxq20100116?IMSfp=TL100116043001r17831 who calls it bottom swing...

.. I'm still confused!

 

[Anthony]

With all due respect to Fingers' ingenuity, I think you should use a conventional swing (high band) mech. That would certainly be appropriate for a 1996 frame, as top-swing (low-band) was only introduced around then, and not generally until 97. All previous mechs were high-band, hence the design of the seat tube.

M739 is good kit, aside from the cranks, but it is a 97 group, so I don't see why you shouldn't fit an M737 or 738 to a 96 frame.

You're presumably looking at Compact Drive (42/32/22 rings), rather than Standard Drive (the rather earlier kit, which had say 48/36/26 rings)

 

[Simbob7]

Front mech

Thanks for the help Anthony and I will be running 42-22T so will be compact. I'd taken earlier advice and links to http://datenbanken.freepage.de/cgi-bin/feets/freepage_ext/41030x030A/rewrite/traut/SHIMANO.html#96 and http://www.mombat.org/Shimano.htm that gave M739/8 as 1996. But you're right that M737 is the other option.

Either way can you confirm if all M737 front mechs were high band (bottom swing) or just some; and similarly with M739 - is the 738 for compact also, by definition high band (and 739 low band) or were there high and low variants of both that you can't tell from the code numbers? Then I know what I am looking for.