Edited by John Stevenson
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Wheel choice
Tyre pressure
Adjusting to new kit/Speedplays
Handlebar drop
Carbon handlebar clamp woes
Leg length
Crank length
Pedal stroke theories
Frankenbike
CODA disk brakes
Tandem computer
I'm planning to upgrade the wheels on my Colnago Master Olympic and I've narrowed the choice down to Kysrium SSC SLs, Campag Neutrons, Campag Eurus (all clincher). I'm 160lbs and my local training roads are very hilly but with poor road surfaces, so durability, weight and comfort are all equally important to me. Last but not least (of course), I want an attractive wheelset in keeping with the classical Italian looks of the Colnago (hence my none-too-radical final selection)!
I know that these wheels all weigh about the same but how do they compare in terms of durability, comfort and general performance?
I'd be grateful for any guidance.
Nick Simpson
Ireland
To discuss optimal tyre pressure you first need to decide on the conditions. Rider weight, road surface and speed play important roles. Safety is also an issue since at pressures much higher or lower than manufacturers' recommended pressure can lead to punctures. Some very fast tyres are not suitable for untidy road conditions, and tyres that are highly puncture resistant are heavier and slower.
You could simply define optimal tyre pressure as the pressure that causes the least temperature rise in the tire, and therefore the least friction for the conditions. However that might not give you the optimal speed in all conditions. A better optimal tyre pressure might be the one that leads to the least loss of inertia.
It is generally known that a higher pressure is better for heavier riders and lower pressure is recommended for rough road surfaces. Depending on tyre construction, different tyres of the same size inflated to the same pressure will behave quite differently.
The manufacturer's recommended maximum pressure is a good place to start. If you happen to be lighter than average, perhaps you can experiment with slightly reduced pressures. Heavier than average riders should probably choose tyres that are larger or accept higher than average pressures to avoid punctures or pinch flats.
Tom Klemola
I work in a bike shop and have been riding Speedplay pedals almost as long as they have been in existence.
The float in your new pedals will seem strange for awhile, but even the biggest sprinters I know who have made the switch get used to the change in short order. Think about working on pushing over the top of your stroke and pulling through the bottom to get more used to the pedals.
I also sent the following to someone new to Speedpalys who had a lubrication question.
The folks at Speedplay recommend dry lubes and used to send White Lightning samples with the pedals. There is a spray kit available for White Lightning that you might try. Finish Line Dry or Krytech also work well. I would avoid a truly dry graphite type lube. Your best bet is to lube your cleats after your ride so that they are dry and ready to go for the next time. Also the pedals need to be greased about every 3,000 miles. To check try to twist the pedal body as if it were a car steering wheel. If you have any play, remove the tiny Phillips screw and use a grease gun to force in grease until it comes out clean on the other side.
Philip G. Pulley
Last summer I bought a new pair of Speedplay X-2 pedals. Fortunately, I decided to wait until after racing season to start using them. I'd been using Look pedals with red cleats for years, but minor knee problems had convinced me to give the Speedplays a try. It is now February and with roughly 4,000 miles on the new pedals, I can definitely say they have helped my knee problems disappear.
What I did not expect – and what for about six weeks gave me a nagging case of illio-tibial band syndrome – was the big difference is stack height of the new pedals and cleats from my old ones. The difference in distance (including adapter plates, cleats, and pedal itself) from the center of the pedal axle to the bottom of my Sidi shoes was 17 mm. This is a huge difference, and anyone changing pedal systems should take this into account. It isn't just the float that is different; a new pedal system can also mean changing saddle height, sometimes quite dramatically.
Peter Leousis
Raleigh USA
I'm looking for a set of bars with a shallow drop. The websites of the major manufacturers provide some spec's but it seems that these fly out the window when I actually see the bars on someone's bike. If anyone has recently gone down the same path, could they please share the results of their research with me? Thanks!
George Poscover
I currently have on test a Titec handlebar intended for cyclocross use that has a shallow drop. They're the Malone model and a full write-up is pending, but in short I'm impressed with the shape. – JS
I'm riding a 2000 Klein Quantum with an Icon MC3 stem and an Easton EC-90 handlebar. I love the bar, as it manages to wipe out most of the road vibration that my shoulders have been accustomed to dealing with. However, it keeps slipping. I position it where I want it, and I tighten the screw on the stem (with most of my body weight, applied at the end of a 10cm long allen key; it's quite literally as tight as I can get it), and I spend about 300 miles on the bike, and lo and behold, the damn thing is 20 degrees out of whack. I'm sick and tired of fixing it once a week; pretty soon, the head of the allen screw holding it together is going to fall apart from the repeated torquings...
Is this a known problem with carbon bars? Will stems just not grip to them the way they grip to metal? Is there anything I can do short of replacing the bar or the stem? Would loc-tite applied to the area between the bar and the stem help? Am I going to have to resign myself to adding "bar adjustment" to the list of weekly maintenance? Should I get used to drops that point skyward at an angle that I dare call rakish? Actually, that might not be so bad, because it drops the height of my hoods a little bit, which probably makes me more aerodynamic...
Really, any insight here would help.
Matt Herz
USA
This isn't a problem I've encountered as I still have the scars from the last carbon bar that went on one of my bikes, and while I'm sure the technology has advanced since 1991, I still can't make the leap of faith to trust the material in that application. Don't ask me why I cheerfully ride a carbon frame… Anyway, can anyone help Matt? Would some ISO 0.2mm shim (aka Coke can) help, perhaps? – JS
My right leg is about 2cm shorter than the left leg, it's the femur that's shorter. I've tried many of the proposed solutions my general comments are:
My own solution in the end was a relatively simple compromise it is:
Frank Mackin
UK
I read with interest all responses to leg length difference. Firstly it is necessary to accurately assess where the difference occurs, lower leg, femur or hip misalignment. The objective of any adjustment to crank length or knee to pedal axle length must be to create a sitting position which gives a stable position for the pelvis. The body will normally compensate for small deviations without creating additional problems so it will not be necessary to fully compensate for the total difference.
Therefore my recommendation is to make small adjustments based on drawing the circle of both legs with an adjustment to either or both of crank length and knee to pedal axle. Although expensive the most positive solution is to have a combination of cranks of different length and pedals with different axle to sole of shoe measurement. In the "old days" this was achieved by using Campagnolo chainsets (which had 4 different crank lengths available) and by filing the side plates of one of the pedals (Old toe-clips pedals). Although I am not familiar with all the latest availability of equipment I am sure that a similar result can be obtained.
As a contra argument I know of one former Yellow Jersey holder who rode the whole Tour de France with different crank lengths through a mistake of the mechanic and who didn't notice till afterwards. So the body will compensate for a lot!
Chris Cooke
Russia
A couple of good books. Anquetil's has some good info, says you should also think about going outside the circle, ie: longer cranks. Hinault's also has a good guide to crank lengths.
Mark Madiot used 180mm cranks. He was approx 171cm or 5'7'' tall. From the mid 50s to late 60s I rode 175mm cranks in Aus Sun Tours and Tas Mercury Tours and am 171cm tall.
You should try 177.5 mm or 180mm.
Mick Shannon
I have 2 bikes, both are 58cm, and both fit reasonably well. One bike has 172.5 cranks, and the other has 175 cranks. I am trying to decide on one length or the other. I notice quicker leg speed with the shorter cranks, but the longer ones seem to have more leverage. Which is better? How do you know? Is there a test of some sort to determine which produces more wattage?
Thanks!
James Klotz
Atlanta, Georgia
Robert Coapman's letter prompted me to write. I agree that certain theories about a certain person's pedal stroke are usually more like a hypothesis, unless you are a serious student of biomechanics, and have many years experience working on these things.
Still, while saying one person's hypothesis is incorrect, which I can grant you Robert, you then make many generalizations yourself, which I don't find backed up by anything approaching even a hypothesis. To say that "fastest riders are those that can stomp down on the pedals the hardest for the longest." What does that mean? The downward force of the pedal stroke is the most efficient? Huge muscular endurance, when being inefficient (stomping) is the most effective? And then to say that a round pedal stroke is mythical is misstating the case a bit – the point really is to become "rounder", not exactly, perfectly round. Even trying to become more evenly distributed left to right, while helping some (as I have heard in the case of Rebecca Twigg, back when force-sensing pedals were first being used by the USCF to measure these things in the early 80's), may hurt others. Also, some athletes that may appear efficient to the naked eye, aren't at all. This may be the case for Anquetil, who knows?
I have taken many athletes into the Sports Performance Program at the UC Davis Medical Center, where Max Testa and Eric Heiden have opened a sports clinic. They have a biomechanical expert there, Judd Van Sickle, who comes up with torque measurements for left and right leg (although not completely independent of each other, yet), as well as measuring the "roundness" of your pedal stroke. They have a unique setup there for measuring roundness of a pedal stroke – a Serotta Size Cycle, equipped with a Computrainer flywheel and a Science version of the SRM. At the end, you get a chart showing your torque output at certain parts of the pedal stroke.
I am not certain even Judd could say what exactly contributes to efficient pedaling, only what the end characteristics of an efficient pedaller are. I am going to give you some of my hypotheses about this topic here. I am not saying that these are completely correct, but welcome any comments, good or bad any of you may have.
I have seen the differences between relatively round pedal strokes (they call them simply more efficient) and ones that are not. I have data and charts to support this. I also know from that data that often the most efficient pedal strokes appear to be ones that are also slightly imbalanced.
I have noticed an easily recognizable and workable way to tell how efficient a pedal stroke is, from sitting through many of these biomechanical tests. It's very common sense and easy for anyone: There is a real difference in the sound of the tire on the wind trainer with the more efficient riders. They had less of that cyclical up and down humming noise, and more of a continuous humming throughout the whole cycle. It was very obvious to me, for example, when I took an athlete I coach – Damon Kluck (pronounced Klook – you know, with umlauts) from the Saturn Cycling Team – that his pedal stroke was going to be WAY more efficient than anyone else I had seen tested, when I heard the sound of him warming up.
It turned out to be the case. At lower wattages, hev appeared to have actually THREE peaks in his pedal stroke. One at near 90 degrees, like most of us, one at 270 degrees, like most of us also, but then a third one, at 180 degrees- at the bottom of the pedal stroke. I agree that the hardest place to work on efficiency is at the top of the pedal stroke. But who is to say that Damon's efficiency does not come from his ability to push over the top of the pedal stroke, but with the opposite leg?
At higher wattages, his 180 degree force output relative to the 90 and 270 degree was not actually a peak, but it was a shallower drop, falling only to about half of his previous torque at peak 90 degrees. His highest pedaling efficiency turned out to be 54 percent – which is to say that at that high wattage (I think it was around 400 or so), his torque was over HALF of what it was at the peak, which is near 90 degrees.
I heard years ago that John Tomac had a very efficient pedal stroke from his mountain biking and BMX careers. Damon was also a mountain bike rider prior to his current emphasis on road racing. This may have contributed. Max Testa had previously said to me that the most efficient athletes came in around 30 percent efficiency, so I was even more impressed by Damon's numbers. I wonder what Tomac's would be.
I have also seen athletes who are completely inefficient, roundness-wise. I have an athlete is, at his highest, 14 percent efficient. At most of his other wattages are around 9-10 percent . It is obvious to me that a certain amount of natural pedaling ability and some luck (not having injuries which limit your flexibility in key cycling force production muscles, for example) play into these numbers.
Based on this data, I had a thought to test myself for efficiency. I am completely out of shape and hadn't ridden but maybe two weeks of serious training in the last year. I was fatter then – (Max measured it around at 19 percent, eeek!) – so I wasn't expecting any big numbers or anything. Still, I came in around between 30-40 percent efficiency, in spite of my lack of fitness. I would also post some big numbers on the Wingate, so it isn't clear to me that pedaling efficiency is not as simple as Robert made it out to sound.
Some assumptions are made here – the abs aren't as strong as the back, etc. This is true of most cyclists, however this is only a tendency, and not actual fact for all cyclists. As an example, I coach an athlete who was a weightlifter prior to this. He has a very balanced physiology from his previous sport, yet his pedal stroke is quite inefficient. Do you think that strengthening your abs would make an impact on your pedal stroke? Maybe, maybe not. No study has been done.
It IS possible to pedal emphasizing different muscle groups consciously – my friend, the late John Stenner would explain this in detail in VeloNews the last year he won the National Time Trial. He was an engineer, so he had an eye for efficiencies where he could find them. His point was that it more about having an awareness of your different muscle groups- so it can be improved. I don't think Damon has such an awareness of his pedal stroke, yet he is very efficient – why? I am not certain – experience is sure to be a certain part of that, but there is much more to be discovered on this topic.
For myself, I find that coaching people to learn a different way of pedaling is key. I have my athletes to short intervals of pedaling emphasizing different muscles groups, or de-emphasizing others. For example, I will tell a rider to pedal with using his quads. This is not going to happen, but it makes the athlete try to use other muscles, and most find it very challenging. I do this several times throughout the year, and also at the beginning of the season, when riding a fixed gear bike – which I have believed in, even when it wasn't popular – recently, the word has come back around how good it is. The kicker for me was that Max Testa likes fixed gear riding.
I think Anquetil was a natural pedaler, like Damon is, pedal stroke-wise. It's too bad someone didn't hook him up to a machine to test this before his sad passing, then this debate would have some real authority to it.
In any case, pedaling efficiency is just one aspect of sport performance, and certainly not the only one they test at Max & Eric's clinic, either.
Regis Chapman
California USA
Thanks for all the nice compliments about the Frankenbike article. The comments about not having to use a road crank with a 52 or larger ring to get a big enough gear are well taken. And you're mostly correct in that using the road cranks was mostly for "the look". If I hadn't been able to come up with a solution I would have resorted to using a triple. As for gearing, as I said in the article, having a 39/28 is more than enough gearing for riding non-paved roads and easy singletrack. If I'm going out to ride technical singletrack I use my mountainbike, it works so much better with suspension. However, I love riding it on non-paved roads and at that it works very well. I raced it one time this year and it worked fine, I ended up third, even with some rear hub problems. Since the article was written I had also found out about the Continental 1.75" tires, and will most likely switch to them when the Chen Seng's are worn out. And one last thing, the Frankenbike moniker wasn't my idea, it was Tech Section editor John Stevenson's so I can't take credit for that, but name fits pretty well.
Ed Morris
I can't take the credit for the term 'Frankenbike' either – I can't remember where I picked it up, but a quick Google reveals it's been around since at least 1999. One for cycling etymologists. – JS
A really interesting article that demonstrates how versatile, with a little imagination an MTB can be. My own build seems to differ slightly as I went for the simplicity of a single ring. With my own project I decided I didn't want the traditional bar end levers and Ergo shifters seemed a touch fragile for those inevitable spills.
The answer was a set of Modolo Morphus levers which are combined brake and shifter units- a mixture of carbon and alloy. The real beauty is they are very similar to some of the Suntour road shifters in the late 1980s whereby the shifter unit was inboard of the brake lever and thus protected. More significantly, the units are fully compatible with Shimano 7&8 and I believe Campagnolo 8&9! This means there are fewer issues should the rear mech resurrected from the spares box/bargain 7spd STX unit expires- a simple adjustment at the lever and just pop on the 8spd replacement. The springs are firm, giving that traditional positive modulation to the lever when using either cantilever or V-brakes. They are quite a rare item here in the UK but St Johns St Cycles in Bath (they have a web-site) offer them for about £50 including cables and instructions.
I still face the problems of suitable tyres, settling for Specialized Hemisphere for the winter tarmac, for 'cross mode I am looking for something more sprightly and as has been commented, that final touch which makes it a cross machine rather than a sensibly modified MTB with dropped bars. I have been desperately searching the net for Avenir "Swiss Army" or indeed anything similar. 1.5 contis are frankly, more savage than required in addition to being quite expensive – particularly as I am prone to tyre experimentation!
If anyone can help me please feel free to e-mail me at:
Michael Stenning
I've serviced these for three years in a Cannondale dealership so I've seen a lot of them. Set up properly they work at best OK compared to XT, Grim, Hayes, etc. Our Barnett trained tech traded his for Avid mechanicals. 90% plus of the customers replaced them after 2-6 months with mechanicals, XT or Hayes.
Bill
We recieved a few other letters with similar advice. Replacement appears to be the best solution. It seems the CODA disk was not Cannondale's finest hour.
The solder method that John Linford describes can be used to successfully connect two computers to one fork mounted pick-up. And in my experience, having a computer mounted on the stoker's bars can be a real advantage in navigating in unfamiliar terrain, where the stoker can track distances between turns, etc. Based on my experience, it is much easier to solder the wires of those computer brands having a two wire, wiring harness, such as Avocet, rather than the single coax cable style that some makes use, such as Cateye.
However, if two computers on a tandem are each wired to their own pick-up, there is the advantage of redundancy, in the event that one of the pick-ups fails or is knocked out of position. However, if completely separate units are used, I would recommend that they are identical units and that they both run off of the same wheel, since that way they should be able to be set up to read identically... no sense in giving the stoker and captain something else to argue over while riding!
Mike Mahoney
Houston Area Tandem Society
I built a system with not two but three computers on one pickup for our triplet. I used small stereo jacks so that parts of the system could be removed or replaced if needed. Lessons learned:
For much more on this, see http://www.alumni.caltech.edu/~ryan/files/tand_comp.html
Steve Ryan
USA
Mount a separate computer for the stoker, intentionally mis-calibrated so she doesn't know how fast you're going.
Evan Marks
NY, NY
My stoker likes going fast – maybe I should calibrate her computer to over-read so she thinks I'm superhuman!