Just in: Culprit Croz Blade Di2 Disc

Disc-ready road frame with Shimano's new hydraulic stoppers lands at road.cc towers

by Dave Atkinson   January 14, 2014  

We had our first go on Shimano’s new hydraulic road disc brakes at their press launch back in October of last year but what we really wanted to do was drag a set kicking and screaming back to Blighty so we could give them a proper go in more, erm, challenging conditions. So we needed a disc-specific road frame to hang them from. Step forward the Culprit Croz Blade.

Culprit are an American/Taiwanese outfit that have fully embraced the disc revolution, offering both the Croz Blade aero road bike and the Legend frame, a seatstay-less design aimed at triathletes. There’s a few disc road bikes out there but the TT/tri bike is the first of its kind that we’ve seen, although in a discipline where aero is everything and with the current crop of discs not optimised for airflow, they might be a bit early to that party. Even so, it’s an interesting bit of design.

The Croz Blade is a monocoque carbon frame, built from Toray T800 fibre. It’s built with a 135mm spacing for the rear hub in order to fit a disc wheel, but it comes with inserts to allow a standard 130mm road hub to be fitted instead, as the frame can take TRP TTV mini-V brakes instead of discs if you prefer.

The head tube is asymetric, 1 1/8” to 1 1/2” top to bottom. It’s fairly long too at 19cm for the 58cm XL frame, but no more so than other aero bikes it might be compared with; none of the current crop are particularly low at the front for a given size.

The bottom bracket is a BB30, and the chunky down tube and chainstays promise to make it an efficient platform. Culprit say that the seatstays are thinned down to improve rider comfort, but we’ve seen a lot thinner. The seatpost comes with the frame as part of the package; it’s an aero section and you can mount the saddle clamp in three different positions to fine tune your ride, or adjust your position for different disciplines.

Culprit claim a weight of 1,150g for the 56cm frame (unpainted) and 470g for the fork; that’s not especially light for a race frame but there’s clearly some extra layers of carbon in there to deal with the disc brake forces, and aero frames tend to be a bit heavier anyway. Our larger frame will be a bit more again, but as it came fully built we don’t have a definitive weight for it.

The transmission, as we said at the top, is Shimano’s new Ulterga 6870 Di2, with the R785 hydraulic disc brakes. We talked at length about them when they launched, but basically Shimano have used the space vacated in the lever by removing the mechanical shifting wherewithal to fit a hydraulic master cylinder. That means that unlike SRAM’s lever, which is noticeably bigger, the Shimano lever is exactly the same shape as the standard Di2 lever, although it looks a bit different thanks to the silver cover hiding the master cylinder and lever piston.

The brakes have been derived from the mountain bike units; They look like Shimano XT callipers but the internals have been tweaked to get the right feel for the road. Heat build up is the biggest issue for road discs, and Shimano have addressed that with Ice-Tech finned brake pads, and FREEZA rotors which have an aluminium central layer with cooling fins on the inside face. The Culprit is running a 160mm front disc and a 140mm disc to the rear.

Ultegra 6870 Di2 has borrowed much of what was introduced with the new Dura Ace groupset, most notably the smaller motors which make the new mechs a lot less bulky; the rear is really no bigger than a mechanical derailleur now. The chainset uses the same four-arm spider design as Dura Ace, which saves weight while maintaining stiffness. Oh, and it’s eleven-speed, of course.

The bike is fitted with Shimano’s new RX31 disc wheelset, and the rest of the finishing kit is supplied by Pro, including a Vibe alloy stem and bars and a Turnix saddle.

With pedals the Croz weighs in at 8.8kg (19.4lb) in this build, so it’s not a featherweight by any means, although it’s a similar weight to the Colnago CX Zero Disc that we also have on test right now. The wheels and the cockpit are the obvious places where there’s an easy saving to be had. We’ll be testing it as supplied, and also swapping the wheels out for something a bit lighter to see how that affects the ride.

24 user comments

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No doubts it will be interesting to get a few miles under the belt of this one. The weight does indeed seem to be an issue with discs. I'm guessing over the next year or so different grades (Tiagra, 105, ultega) will be issued with differing performance and cost. For now SRAM seem to have their anchors jammed on!

posted by Guyz2010 [280 posts]
14th January 2014 - 12:49

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Price?

posted by giobox [234 posts]
14th January 2014 - 13:20

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Ugly paint finish ruins what is actually quite a tidy and well proportioned disc bike

posted by wildoo [24 posts]
14th January 2014 - 13:21

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It's a head-turner, that's for sure.

If I could have, say, 6 bikes, would it stop me drooling over others that I don't have?

posted by notfastenough [2929 posts]
14th January 2014 - 13:42

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Given its Di2 11spd and Culprit dont do frame price by halves either (good frames mind!), I'd be very surprised if this comes in anywhere under 3 grand!

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posted by bici1977 [29 posts]
14th January 2014 - 13:52

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That is one UGLY bike

posted by Simmo72 [274 posts]
14th January 2014 - 14:11

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Not pretty.

posted by Guyz2010 [280 posts]
14th January 2014 - 14:52

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Interesting use of crayon in the design process.

posted by belgravedave [164 posts]
14th January 2014 - 14:59

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notfastenough wrote:
It's a head-turner, that's for sure.

Yeah turning the other way....it's ugly

posted by SuperG [51 posts]
14th January 2014 - 15:05

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I like it Drooling I'd be interested to know the price

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posted by fancynancy [54 posts]
14th January 2014 - 15:43

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ugly, ugly, ugly....

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posted by andybwhite [174 posts]
14th January 2014 - 15:43

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The paint scheme is really not to my tastes, but I'd love to have a go on it.

Am a little surprised that Shimano have not yet released a higher-spec road disk wheelset. With the first road disk groupset sitting at Ultegra level, a 3-series wheelset seems a bit below par. I guess an RX61 or RX81 is probably in the pipeline....

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posted by andyspaceman [213 posts]
14th January 2014 - 15:55

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That is a pretty interesting seat tube design

posted by jarredscycling [436 posts]
14th January 2014 - 16:00

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Am I the only person thinking that this bike should be banned from use on public roads. I would rather ride a bike with no brakes than that bike. It just looks wrong.

posted by DeanF316 [83 posts]
14th January 2014 - 16:50

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The typography is hideous (as usual for a bike) and it is by no means a pretty bike but there is something about it's unconventionality that is quite compelling. It is different, in a good way and I wouldn't get bored of looking at it.

Never in a hurry on a bicycle.

posted by GoingRoundInCycles [134 posts]
14th January 2014 - 20:53

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It's hard to look at a bike when you are riding it. Maybe this is were you are going spending too much time looking at bikes instead of riding one lol

posted by DeanF316 [83 posts]
14th January 2014 - 22:04

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Holy Jesus that is one fugly bike. Was it painted in the dark by any chance? Thinking

posted by Ultimateweevil [36 posts]
15th January 2014 - 1:11

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Blimey, bike aesthetics have come a very long way, haven't they?

posted by Ross K [14 posts]
15th January 2014 - 7:39

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I think it looks great! But I like unconventional design.

posted by welly2 [9 posts]
15th January 2014 - 10:58

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I ride my bike according to its usefulness not how everyone else thinks it looks!

posted by McDuff73 [44 posts]
15th January 2014 - 18:39

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The whole reason I would not consider a road bike with discs... 8.8kgs you have to be kidding me, there is no amount of modulation that would offset 2kgs!!

Stop...... Carry on!

posted by benn jones [13 posts]
15th January 2014 - 19:05

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benn jones wrote:
The whole reason I would not consider a road bike with discs... 8.8kgs you have to be kidding me, there is no amount of modulation that would offset 2kgs!!

Yeah - because all disc bikes would weigh 8.8kgs or more....

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posted by fukawitribe [296 posts]
15th January 2014 - 19:28

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a lightweight ultegra Di2 bike is about 7.5kg; the Orca we just tested comes in at 8.1kg, in a slightly smaller size. this culprit is 700g heavier than that but it's carrying a bit of extra weight in the RX31 wheelset over and above the discs, probably 200g. so it's 500g more than the similarly specced orca. that's not an aero frame, and that normally adds a bit of weight for the deeper section tube profiles and seatpost. So probably another 100g there, making the Culprit 400g heavier than an equivalent non-disc build. that's more or less the penalty I'd expect to see right now. to say it's 2kg heavier than a UCI-limit bike is true, but it's not comparing like with like

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posted by Dave Atkinson [7252 posts]
15th January 2014 - 19:52

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having said that, i've seen Di2 bikes at under 7kg. But that's with very light wheels and a lot of carbon finishing kit. one of the issues with discs right now is that there are hardly any good lightweight wheelsets. but they'll come with time.

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posted by Dave Atkinson [7252 posts]
15th January 2014 - 20:01

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