K2 / Proflex Riders Group

General => Tech Forum => Topic started by: gaf16 on February 25, 2006, 09:54:51 pm

Title: proflex 856 - front mech info
Post by: gaf16 on February 25, 2006, 09:54:51 pm
is a top or bottom pull front mech required for the proflex 856 frame?
Title: Re: proflex 856 - front mech info
Post by: orange on February 26, 2006, 12:26:42 am
My XP-8 which I think is the same as an 856 is bottom pull. Have a look in my gallery, if my bike looks a bit like yours then it's a bottom pull.
Title: Re: proflex 856 - front mech info
Post by: Simon on February 26, 2006, 01:44:10 am
You need a 31.8 conventional mech (not top swing)bottom pull.

Simon.
Title: Re: proflex 856 - front mech info
Post by: orange on February 26, 2006, 02:36:30 am
I've gone top swing on both my XP-8 and 857 - should I not have? I need it particularly for the 857 else the swingarm gets in the way...
Title: Re: proflex 856 - front mech info
Post by: gaf16 on February 26, 2006, 03:37:23 am
thanks guys.
i'll get on the bay later to find an xtr bottom pull conventional swing.
will a top swing not work at all?
Title: Re: proflex 856 - front mech info
Post by: orange on February 26, 2006, 04:00:01 am
I use topswing, no probs.
Title: Re: proflex 856 - front mech info
Post by: gaf16 on February 26, 2006, 05:19:09 am
orange,
thanks for the info.
i owned an orange x1 btw. i wish i'd never sold it and have been looking for a replacement over the last few months.
hang on to it!
Title: Re: proflex 856 - front mech info
Post by: Simon on February 26, 2006, 06:45:51 am
Conventional swing lasts alot longer (IMHO) than top swing,but whatever works go for it.

Simon.
Title: Re: proflex 856 - front mech info
Post by: gaf16 on February 26, 2006, 07:18:52 am
thanks again guys.
managed to source a conventional xtr m900 front mech now.
Title: Re: proflex 856 - front mech info
Post by: orange on February 26, 2006, 08:02:22 am
Somebody else with an X1 - I've never seen another one in the 10 years I've had mine! I'll be keeping it for sure. Still have original (unserviced!!) Stratashock that came with it - still going strong!

Anyway, this is a Proflex forum, best not stray! I've uploaded a (muddy!) photo of it to my gallery from the Real Ale Wobble 2004.
Title: Re: proflex 856 - front mech info
Post by: shovelon on February 26, 2006, 08:38:49 am
Stray away!

Proflex and Orange share some geometries. Good to hear that another high pivot rear suspension scores highly on your liking.

I love the simplicity of my single, high pivot bikes.

Terry
Title: Re: proflex 856 - front mech info
Post by: will on February 26, 2006, 12:42:10 pm
Dude, I don't swing either way!

Tear it off, throw it away, get rid of the big & little chain ring, weigh your new extra light bike & ride it like you stole it!

Check my white 856 on the gallery...

http://idriders.com/cgi-bin/album_k2.pl?photo=Will/DSCF0129.JPG

Title: Re: proflex 856 - front mech info
Post by: Sprucey on February 27, 2006, 06:54:47 am
Top swing front mechs have the mounting band roughly level with the derailleur cages.

Conventional has the mounting band considerably higher.

General wisdom is that concentional swing are for hard tails (but check where bottle cage mounts are as on some frames they interfere with conventional band mounts) and top swing for FS bikes as they take up less room and are less likely to interfere with a swing arm.

Simon is right - if you can fit a conventional mech to an FS bike then do so - due to the way the pivots are located they last longer before getting sloppy.

These days, Shimano XT and Deore front mechs are multi tube size and both top or bottom pull which makes life easier for all - including us the retailer!

Imagine the scene 2 years ago - with XT mechs you had three tube size, two derailleur types and 2 cable routings so we had to stock 12 different front mechs! Now we only have to stock two types (top swing or conventional)  - how sensible is that?!

Sprucey
Title: Re: proflex 856 - front mech info
Post by: jimbob on March 19, 2011, 04:26:48 am
A bit of thread resurrection here, but after a search I thought I'd add to this rather than starting afresh...

I need to replace the sloppy XT M739 front mech on my 857, I gather the band size is 31.8? same size as the seat tube clamp I bought last year???? I also gather I need a bottom pull mech?  And from the looks of things it will need to be top-swing too?

Will this be ok?  http://www.chainreactioncycles.com/Models.aspx?ModelID=20684 (http://www.chainreactioncycles.com/Models.aspx?ModelID=20684)

or if I feel flush....? http://www.chainreactioncycles.com/Models.aspx?ModelID=54891 (http://www.chainreactioncycles.com/Models.aspx?ModelID=54891)

it's to fit with a triple-ring M739 chainset with 42-32-22 rings.

???
Title: Re: proflex 856 - front mech info
Post by: fyrstormer on March 19, 2011, 01:19:07 pm
As long as this thread has been resurrected: I've considered putting a top-swing derailleur on my 756, but it looks like the mounting clamp would interfere with the swingarm pivot welds. What about a top-swing derailleur mounted on one of those plates that's held in-place by the crank bearings? Do those fit?