Home > Other Fun Stuff > Gadgets & Hacks

Found: Crank Tip Promises Less Fatigue & Greater Power w/ Unique Dual Swingarm Pedals

63
Support us! Bikerumor may earn a small commission from affiliate links in this article. Learn More

cranktip-racing-pedal-hero-3

Free power and less fatigue. That’s every roadie and triathlete’s dream, right? As far back as 1898, inventors have been looking toward the design of the pedal as a means of improving performance on the bike. Looking quite a bit more advanced than that first Ramsey Swinging pedal, the Crank Tip Racing Pedal promises reduced fatigue and increased power all with a simple change of your pedals.

Utilizing a dual swingarm design, the pedal is able to float laterally during rotation. It’s this back and forth movement that Crank Tip claims is responsible for a biomechanical advantage capable of reducing a rider’s heart rate by “5-10 beats.” Slide into the details next…

crank tip pedals  (1) crank tip pedals  (3)

While they may look a little crazy, all that extra hardware simply allows the clipless portion of the pedal to float back and forth from the section attached to the crank. Think gliding chair or similar, while the fixed portion threads into your crank like a normal pedal would. The Crank Tip pedal uses what appears to be a fairly standard 3-bolt road cleat which should make clipping in and out familiar.

crank tip pedals  (4)

The main idea behind the pedals is twofold. First, the swinging action supposedly reduces leg fatigue since the pedal is able to slide back and forth. Crank Tip states that this movement lessens the feedback at the pedal which results in a smoother pedal stroke, and therefore less strain on the muscles. The other concept to the design is that when the pedal is approaching the 4 o’clock position, it results in a foot position that is 12mm lower, and 16mm further forward. Their claim is that this effectively increases the length of the crank arm gradually which provides increased leverage and torque at the key position in the pedal stroke.

Even if the pedals work exactly as claimed, there seem to be two major hurdles to contend with – weight and price. With a listed weight of 1.3 kg (1300g!), they are over 1000g heavier than something like a pair of Dura Ace PD-9000 pedals 700g (see Henk Vogels’ comment below). At $499, they are also almost double the price. However, the pedals do include a money back guarantee with the company stating they will refund all money including shipping cost if you are not fully convinced with their performance.

cranktip.com

Thanks to Eddie for the tip!

Subscribe
Notify of
guest

This site uses Akismet to reduce spam. Learn how your comment data is processed.

63 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
dead
dead
8 years ago

Watch out for pedal strikes!

McClain
McClain
8 years ago

Sorry, but what exactly does this product do? Reminds me of this:

http://pardo.net/bike/pic/mobi/d.pmp-cranks/z-torque.html

Except that it only seems to displace the spindle down and forward by 12 & 16mm… meaning it might create some really difficult fitment issues. What exactly is the benefit?

Dave
Dave
8 years ago

It looks more like a subtler version of the crank-pedal combo Paula Newby-Frazer used in the early ’90 to me.

McClain
McClain
8 years ago

Ok, by studying the diagrams a bit more and watching the video, I think I get the idea a little better. Doesn’t seem worth it by a longshot though.

Also, they would likely not be allowed in UCI (not that that matters much to us here), and it seems like it would create a disconcerting disconnect within the stroke, where you could move both feet independently in both directions while not pedaling. I’d try them out just for kicks, but it seems like it’d be strange. (deleted)

erik
erik
8 years ago

uci wont like this one…

pk
pk
8 years ago

just in case you don’t understand the concept, this is basically making the lever arm longer on the down stroke. so more leverage on the down stroke, but there’s definitely compromises like no power at the top and bottom (transition periods) and decreased leverage on the up-stroke (which if your a triathlete trying to recruit all your muscles seems like a bad idea), and putting the seat lower when your TT bars can’t will likely increase drag.

that being said it’ll be noticeably feel easier to push a bigger gear.

TN
TN
8 years ago

Isn’t this another take on the same concept as asymmetrical chainrings? Also the design of the asymmetrical chainrings work with the opposite logic, harder to push when you are at your maximum position on the crank revolution (this is easier to push on the exact same spot)

Mirwin
Mirwin
8 years ago

Potentially a mechanical advantage, but 1.3 kg’s?! Need to compare these with the Dura-Ace pedals, same person, same bike

Dave B
Dave B
8 years ago

Seems a like oval chainrings in concept but more expensive and way heavier.

Jay Reeder
Jay Reeder
8 years ago

Dumb, if you want longer crank arms, just install longer crank arms.

Hobbanero
Hobbanero
8 years ago

Seems like it is a different angle on the non-round chainring approach. If you use longer cranks with non-round rings (eg. Rotor Q or Osymetric), then I think you get the same effect with far less weight. And the independent studies don’t show performance gains for non-round rings, though I use them and like the way they feel.

I am not a scientist, but I suspect that the relatively low torque at 90-100rpm mostly eliminates the benefit of mechanical advantage, and your momentum carries you through the weak spot at the top of the pedal stroke. At 60rpm I can see there being an advantage, and my anecdotal experience is that the Q rings make more difference on the mtb, where on a steep, rocky climb you are going to need to apply torque all the way around the pedal stroke.

Andrew
Andrew
8 years ago

Keep in mind, you get a mechanical advantage on the downstroke but you also have to move your leg that much further during that part of the stroke thanks to the larger circle you’re pedaling through at that point.

craigsj
craigsj
8 years ago

Free power for nothing! When will cyclists learn?

Pedals don’t produce any power and these certainly won’t produce “more”. All the power comes from your legs and you won’t go faster, easier. It’s a variable length crank arm and science has already shown that crank arm length does not significantly affect power output.

It appears the pedals aren’t synchronized with the crank stroke so it doesn’t even work like the diagram says.

Remember that if the lever gets longer, the foot has to get faster so your cadence must slow down. No comes for free.

These ideas have been tried and failed over and over for a century.

mudrock
mudrock
8 years ago

Riders who pull on the upstroke tend to ankle more, which would pull back on the pedals and give this an oval path. Seems to me the greater lever on the downstroke might be negated with the loss of efficiency from free play.

But giving the rider a greater lever on the power stroke is definitely a good idea.

Dude
Dude
8 years ago

From a leverage perspective it’s doing what non-round chainrings do but at the crank. At 90-ish degrees off, putting the higher leverage at the power stroke. So… biopace?

dumbass
dumbass
8 years ago

yep, can do exactly the same with non-round chainrings, except with less weight, go figure.

Stephen
Stephen
8 years ago

Just imagine if Crank Tip were to team up with MagLOCK…those would be THE ULTIMATE BIKE PEDALS!!!

Rider_X
Rider_X
8 years ago

Ok I am confused. I like the idea of a longer lever on the downstroke and a shorter return path. This would result in a smoother spin and potentially a smaller dead spot in the pedal stroke.

*However*, looking at the diagram if the resulting pedal stroke is indeed circular you can get the same benefit by moving the bottom bracket down and forward. If you already have a correct position this would decrease power.

*Correction* – moving the BB with regular cranks would result in the same pedal path, but the crank *leverage* would be less than the swinging pedal design.

For those talking about non-circular rings, these do not change the crank leverage like you are with this pedal design. Having a shorter return path and lower leverage during on the back stroke could be good as you cannot generate as much power on the back stroke (no matter who you are) and the shorter leverage would make it easier to turn the pedals over at a higher rate with a bigger gear.

feldy
feldy
8 years ago

Agree this seems analogous to oval chainrings, however, it seems like it’s more like biopace than all the new school versions. I.e. this gives more leverage through the power stroke, but why do you need more leverage there? Couldn’t you use more leverage through the dead spot instead?

McClain
McClain
8 years ago

@Andrew- the circle is not larger, it is displaced, and presumably not perfectly round…

I admire these guys for putting in the effort, and maybe it does feel good in a similar way to ovalized rings. Nonetheless I think it’s dumb… :-/

McClain
McClain
8 years ago

@feldy
I think you have it backwards…

rs4x reinvented
rs4x reinvented
8 years ago

I would compare it to Rotor’s RS4x cranks. I had a chance to ride those cranks for several years (video here: http://www.youtube.com/watch?v=qwLLpd5c1M8)

Lengthening the time between the 1 to 4 position during the pedal stroke while simultaneously shortening the 7 to 12 position opens the hip angle, provides the benefits of shorter crank arms during latter half of the pedal stroke while increasing the length of the lever during the portion of the pedal stroke when there is the greatest ability to transfer the rider’s weight into the pedal stroke. There is very little power produced during the latter portion of the pedal stroke (see research and Shimano’s reason for it’s 4 arm crank). Mechanically eliminating the ‘dead spot’ of the pedal stroke is advantageous. The RS4x did test favorably, effectively reducing lactate levels…. but the weight of the crank was significant. That was not a factor on flat courses. I for welcome Oval chainrings, and welcome even more ways of using eccentric mechanisms to change the effective pedal stroke to be more efficient. http://www.ncbi.nlm.nih.gov/pubmed/11404667

Eccentric cranks have been used in locomotives forever…

rs4x reinvented
rs4x reinvented
8 years ago

My criticism: the limited eccentric motion created by this linkage design could have been accomplished by a much tidier single eccentric pivot. See the Ibis Mojo eccentric pivots as examples… and note that the different in opinions when when comparing a mechanically advantageous change in path of movement for suspension compared to pedal stroke – very interesting.

Andrew
Andrew
8 years ago

@McClain, yeah, I was just trying to provide a good analogy for people. 🙂

Mike
Mike
8 years ago

Henk Vogels – The chubby guy in red – placed 10th in the 1998 Paris Roubaix. This is the fire time I’ve seen him do anything like this. Notoriously taciturn.

sam
sam
8 years ago

My first thought was that Henk’s been in a good paddock.

Veganpotter
Veganpotter
8 years ago

I could see the benefiting people with short femurs but long tibias. That way…you’re crunched up less at the top of the pedal stroke but can get a good extension at the bottom. This would also be bad news if you have a short tibia but long femur bone.

***The weight is pretty off putting though, and whats the q factor going to be?

Alex @ Hermes Sport
8 years ago

Vista did something really pretty similar to this a few years ago with their Synchro cranks, whereby the pedal spindle was mounted eccentrically inside a large bearing at the end of the crankarm, which accomplished a pretty similar effect. Bearing wear on the crank-end bearing was supposed to be the ultimate flaw with them, from my understanding.

Still, this sort of thing, oval chainrings or eccentric pedals is really interesting, a pretty direct way to turn calories into more forward motion.

CORider
CORider
8 years ago

My grandfather used to say:

“If it aint broke, dont fix it.”

Kind of applies here…..

Che
Che
8 years ago

Why not, just use q-rings. They in theory do the same thing and don’t add has much weight.

anon
anon
8 years ago

i want to ride these on a fixed gear.

craigsj
craigsj
8 years ago

“Still, this sort of thing, oval chainrings or eccentric pedals is really interesting, a pretty direct way to turn calories into more forward motion.”

This doesn’t say anything at all. Bicycles are a way of turing calories into forward motion. So is walking and it’s even more direct.

What_the_****
What_the_****
8 years ago

I think the oval chain-ring set are more effective than these heavy pedals. you can take the doval chain-ring set on ebay, lighter, cheaper and more simple.

Dustin
Dustin
8 years ago

$500+1000g later and only minimally diferent from moving your saddle further back and up…

JBikes
JBikes
8 years ago

The red/green circle diagram makes it seem like these accomplish want is essentially a change in geometry (ST angle and length). I know that is not what is actually happening, but the diagram is poor at depicting this since the swing pedals maintain a perfect circle, as shown in green.

Jez
Jez
8 years ago

Like normal, mass skepticism. OK, fair enough. But these guys are not unknown riders. They’ve got pedigree, and Henk is nobody’s fool, in particular. If they think it works, I’m already interested. However, I’d like to see power meter output to know for sure. Biomechanically, the leg is not designed to work in circles (as per normal crank action), hence the interest in systems that emulate the leg’s natural action more closely (oval rings). No doubt, this design could be significantly reduced in weight and in price with mass production, so don’t even bother getting caught up in that. Let’s see if it works first – every innovation is greeted with similar negativity, and the bad ones go away, so time will tell…

mudrock
mudrock
8 years ago

I don’t know why everyone is equating this device with oval chainrings – it’s almost the complete opposite. Oval chainrings give you a bigger gear in the powerstroke, making it harder to pedal – but because you’re in the powerstroke that’s ok.

This device gives you a longer lever with the same gear, making it easier to pedal in the powerstroke. That may be why the racers are so impressed with the pedal – your legs fly through the stroke – you feel more powerful. And it also quickly gets you through the deadspot up top.

(someone may have broached this already but l didn’t feel like reading all 34 comments)

Almon Poole
8 years ago

I already use a variety of rotor rings which seem to do that same job this pedal does. However, with all the miles I put in on multiple bikes it may be less costly running these pedals and round chain rings. I’ll have to check them out.

tp
tp
8 years ago

I still ride with the Vista magic x pedals, which use the same idea. I do not know or care if they add any power, but the feeling of smoothness of the pedal stroke was instantaneous when I first installed them.

The Vista pedals weigh 125g apiece, and used to cost about 200$ (do not recall the exact price). Yet Vista is out of business.

Downsides: the ball-bearing sits next to the crankarm and pushes the foot out, widens the stance by maybe 8-10mm on each side. The foot sits lower, so higher risk of pedal strike in corners, but also lower center of gravity which is a bonus on fast descents.

fast one
fast one
8 years ago

I dont know what you guys are talking about, I have bought a set of these pedals and I know they feel better, why cause when I replaced them and return to my old pedals they felt like I had two left feet and i had to constantly check to make sure I was in the right gear at certain points in my ride as the bike felt harder to pedal, also they do not work in any way like roto rings. I dont know what you guys are saying cause the pedals cannot move back and forth independently that much that you can feel it, they cushion the rotating force at the bottom of stroke and at the top stroke your hip is better placed as its lower and less stressed. These are my experiences and I will not ride anymore without them.

fast one
fast one
8 years ago

Mind you I bought them when they launched at $250.00 per set… guess I was the lucky one

WheresWaldo
WheresWaldo
8 years ago

@Stephen who wrote on 01/09/15 – 1:21pm
“Just imagine if Crank Tip were to team up with MagLOCK…those would be THE ULTIMATE BIKE PEDALS!!!”

You forgot to add Nikola, might as well have your foot flopping around all over the place and side to side too while you pedal. Now that combination is ULTIMATE!

Ronin
Ronin
8 years ago

CrankTip, if you’re reading this, send me a set and I’ll review them and put this argument to bed… 🙂

Send a set to GCN and ask them to test them at Bath University. In the video above, I’m not sure those two guys would just straight out lie, so let’s just wait ’til the reviews come in.

craigsj
craigsj
8 years ago

“Biomechanically, the leg is not designed to work in circles (as per normal crank action), hence the interest in systems that emulate the leg’s natural action more closely (oval rings).”

This is complete nonsense and oval rings don’t change the foot path anyway. You still pedal in circles with oval rings and I’m amazed at the stupidity of this repeated claim.

“Let’s see if it works first…”

We already know it doesn’t because it’s based on a premise that have been disproven.

“I don’t know why everyone is equating this device with oval chainrings – it’s almost the complete opposite.”

mudrock is right about this. These have more in common with Biopace than with modern oval rings. They are, in fact, most like the Rotor RS4 crank mentioned earlier except that they are times opposite of those cranks and therefore work against you. If this kind of contraption worked at all, and it doesn’t, they have gotten it backwards.

greg
greg
8 years ago

these dont make the crank arm/lever arm longer. they may change where your foot is, but there is still the same pivot at the crank’s pedal threads. this offsets the foot to the crank’s pedal threads down and forward, similar to the aforementioned Vista pedals and Shimano’s old Dura Ace AX(?) toeclip pedals, essentially creating a “negative stack height” to your foot. on top of that, this system has a small parallelogram “hammock” for the platform, what that does, who knows. but it certainly does not make any lever longer.

WannaBeSTi
WannaBeSTi
8 years ago

I wonder what would happen if you mixed the Rotor RS4x crank, Osymetric chainrings, and crank tip pedals….
Would you even need to pedal? Do three wrongs make a right?

Dex
Dex
8 years ago

If you run oval chainrings and these pedals you will get double the power. You could essentially go from Cat 4 to Cat 1 just by spending $1000.00. I would rather spend the money on a Stages crank and a subscription to Sufferfest just so I don’t look like a dork riding with my club.

rs4x reinvented
rs4x reinvented
8 years ago

greg, you write that the “pedal threads down and forward”…. “FORWARD”

So, you recognize that the pedal moves forward of the pedal insert on the crank. How is that not creating a longer lever?

Also, why the negative reactions to a mechanical solution to the pedal stroke, one that creates a longer lever during the pedal position where the rider can put more of their body weight into the pedal stroke and minimizing the lever during the portion of the pedal stroke when there is little to no power contributing to forward movement while also minimizing ‘bunching up’ at the hip…., but no negative reactions to suspension designs like DW-link that mechanically change the path of swing arms through the use of parallelograms and eccentric pivots?

Bikr
Bikr
8 years ago

This combined with PowerCranks and Q Rings…now you’re talking!?!

Juan Pablo
Juan Pablo
8 years ago

Great Idea! Congrats guys! Sound.

Subscribe Now

Sign up to receive BikeRumor content direct to your inbox.

Subscribe Now

Sign up to receive BikeRumor content direct to your inbox.