I'm certainly no expert on mountain biking, but one thing I've learned from experience is that suspension components don't just soak up bumps... they soak up muscle energy as well, especially when climbing.

As a result I find it impossible to climb effectively with the rear shock unlocked. I wonder if that's what is happening to you as well?

I'm about the same weight and and slightly taller.
Rob

Yes it's happening to me as well Rob, but even when i do the lock out as now i had the propedal, i would switch it 'on' but still facing the same problem...

Not sure if the geometry of my riding is correct ?

I'm currently using a 70mm stem...

Hi, sounds like your setup is slightly out, what type of handlebars do you have how long is the stem and what rise is there on the bars.

I have changed forks 3 times to get the right setup, the standard rear setup gives about 5" of travel and was designed with a 4" fork in mind, normally I would believe that a higher back end would aid climbing, but there are other factors, I'm only 5' 7" tall and I have the 6" rear and 6" forks, I am sat fairly far back, which is great for DH and not too bad for uphill as my stem is 70mm (not too short).

You may need to get a longer stem higher rise bars or a cranked seat post or all three, see if any of your mates are interested in loaning you stuff or swap bike with shorter friends on a ride to see if they have the same prob on your setup.

I started with a 140mm Marzocchi AM3 which worked well, then as I was doing bigger stuff I bought some 170mm Marzocchi Junior T's these messed the geometry up completly, great DH but uphill was really difficult almost painful, now I have Maverick DUC 32's which are short for 6" travel, and there great, I also have a Fox RP23 and I only ever put pro-peddle on, on extreme & very flat climbes, mostly leaving it in the middle and switching PP off if I want to decend super quick (I find PP helps to get bigger air on small jumps)

les,
i'm currently using the Ritchey low riser bar with my thomson 0 degrees 70mm stem.

My front is marzocchi mx lo (100mm travel @ 4 inch) and with my rear of 7.5 inch RP23 x 2 which gives me approx. 5.5" rear wheel travel i think.

I'm 6' feet tall by the way...

You may find because your effectivly bein gpushed over the handle bars (you have 6" rear & 4" front Sus) combined with your height, that you may have your Seat a bit low, they say there 19" frames, but mine feels alot smaller than my other 17" frames, I like that, but it doesn't help the climbs, I too have an RP23 and ten to leave the pro peddle off unless its really flat climb.