Shimano Zee M640 disc brake review
Shimano’s Saint-derived budget DH Zee group has been around for ages and it’s gone up in price recently, but this underdog parts collection is still nowhere near as celebrated and popular as it deserves to be. These 4 pot brakes are a prime example and when it comes to masses of stopping power for not much money there’s still not much that’ll beat this no-nonsense Japanese gravity anchor.
Like a lot of our favourite cost-effective brakes such as SRAM’s Code R and Guide RE, Zee mixes an XC lever with a DH calliper. In this case you’re getting an SLX lever with moulded dimples on the blade for dirty finger grip and a recessed Allen key reach adjuster for crash proofing. The I-Spec shifter compatible bar clamp is hinged for easy fitting, but gets a cunning back-up ‘safety pin’ so even if the clamp bolt falls out the lever won’t actually fall off the bar.
The Servo Wave lever cam mechanism moves the pads very quickly at the start of the stroke then reduces closing speed and increases leverage to boost power at the bite point. That gives plenty of rotor clearance for easy set up and quiet running despite the long calliper and pads.
Zee and Saint are the only Shimano brakes with an inside edge hose attachment to protect them against accidental crash and uplift damage. In fact the two piece, bolted together four cylinder calliper is actually the same as the £50/€129 more expensive Saint brake. The difference is that you get standard brake pads secured with a split pin rather than finned ‘IceTec’ pads with a screw-in securing pin.
Despite the bulky looks, weight isn’t that high considering the power it delivers
Even though the mineral oil internals are theoretically more prone to overheating compared to synthetic DOT 5 brake fluid, we’ve never had overheating problems in normal conditions. There’s nothing to stop you upgrading the pads for better big mountain/extended braking tolerance if you find you need it, though.
Either way, you won’t be short of power with Shimano Zee’s on your bike. They’re one of the most powerful brakes we’ve tested on a dynometer (only outperformed by Magura’s MT5/7 four cylinder brakes). The Servo Wave leverage change means they come on very strong as soon as they contact, too, so you’ll need to be careful they don’t hurl you over the bars and into the distance while you learn their power curve.
Once you’ve got used to the feel, modulation and consistent lever feel is good, with none of the wandering bite point issues we’ve had with more recent generation Shimano brakes. They do take a while to bed in and if not used for a few weeks they can feel glazed for a couple of runs until you warm them through again.
Overall reliability is very good, though, and bleeding is easy enough with Shimano’s ‘One-Way’ kit. Despite the bulky looks, weight isn’t that high considering the power it delivers. The Shimano Zee’s pricing is very competitive, too.
• Shimano Zee Weight: 461g (with 180mm rotor and adaptor)