by Ben Haworth
February 8, 2011
It's been hammered a bit now.
Pivot Mach 4
From: Upgrade Bikes
Price: £1,599 (frame only)
In my last update where I had finally found a suitable fork for the Mach 4 (Marzocchi Corsa), I said that I was “really looking forward to seeing what the Pivot Mach 4 can do now .. it’s time to give it some hammering, some proper stick.”
Well that’s what I’ve been doing for the last few weeks.
The bike is still handling very nicely. I have still got a 50mm stem on there. It seems to work very well with the wide (740mm) handlebars. The width of the bars positions my arms wider and so my whole upper body in general gets put in a very similar place to where it would be with a longer stem and narrower bars. So I don’t feel the short stem translates into a short, cramped cockpit with the attendant wandering and wheel-lifting that goes with such a cockpit. It helps that the top tube is on the rangy side and I don’t have to run my saddle too far back on its rails etc (which would lead to a slacker “effective” seat angle).
Although running wider bars can make it harder to pop the front wheel up, it does mean that wheels-on-the-ground rapid riding is much improved. My cornering is so much better with wider bars.
Anyway, enough talk of build kit and cockpits, how does the frame handle?
I’ve got used to how the rear suspension feels and reacts to things and I think I’ve perfected the setup.
At first I ended up running it with the ProPedal switched on but in its lightest setting (Fox RP23 rear shock). When running zero ProPedal I didn’t really have a problem with excess pedal bob, but I didn’t really get on with how the rear could compress under cornering – and how it could “fire” you out of the corner when the rear re-extended.
But running even a small amount of ProPedal seemed to unduly affect how the bike handled big hits and landings. So in the end I’m now running the shock with 25% sag, zero ProPedal, and crucially quite a lot of rebound damping (it appears too slow when you do the classic “car park” test but it doesn’t ride like out on the trail).
If it’s one thing I’ve learned about the DW Link system it’s that it requires a LOT more rebound damping than you might be used to on other suspension systems.
With this setup the back end is finally feeling taut, grippy, stable and has that “extra inch” kinda feeling that decent DW Link bikes exhibit.
The frame really is incredibly stiff. Even though I’m running “normal” QR axles at both ends it’s felt a lot less twangy and flexy than some bolt-thru bikes I’ve ridden. It’s this stiffness – combined with the excellent rear suspension feel – that encourages the bike to be ridden as hard as I can. At no point does it enter my head that I’m “only riding a 100mm XC bike” and I pause or temper my riding behaviour.
So do I have any niggles?
Well, I have finally weighed the bike. It’s a not bad, but not great, 27.7 lbs (inc. Time Atac pedals). For some reason I expected it to be a bit lighter than that. I’m loathe to remove the only two “could-be-lighter” components from the bike – the fork and the adjustable seat post – because they add a lot to the great ride of the bike.
Without wishing to sounds overly British, the frame is a pain to clean after it’s been covered in mud. All that suspensiony stuff around the BB/seat-tube area is a bit of a ‘mare to get at and flush out. And when riding, it’s hard to say whether another system would have dealt with mud better, but I’ve experienced quite a bit of the front mech clogging-up with mud and consequently not shifting so well.
Personally I’d be more than happy to put up with these mud struggles due to the way all that suspensiony stuff makes the bike handle. But there are some folk out there for whom mud friendliness is higher up their list.
Well, despite what I’ve just said above, I’m going to have to try and lose some weight from the bike by changing some bits. The adjustable seat post is going to have to go – to be replaced by a hugely-lighter I-Beam system hopefully. And I’m going to try a different fork up front. Something lighter, with more travel but not much more axle-to-crown height. Probably bolt-thru, which will require a new wheelset too.
Decisions, decisions… again.