Wednesday, June 15, 2005

Time Pedals

After flopping around on MTB's for a couple of years I eventually got fed up with my feet slipping off the pedals and the loose pedal then impailing itself hard into my shin. A solution needed to be found and magazines/internet mentioned these damn fangled SPD (Shimano Pedal Dynamics) systems.

Upon further investigation it appears that the pedals and shoes have a mechanism that clamp the two together which are released again with a twist of the ankle. Now that might sound a little odd but yonks ago, I'd ridden road bikes (damn it, the secret's out!) when toe clips were common place. If you tightened 'em up they were quite frankly lethal, but at least you typically managed to stay upright on the smooth road surfaces where you also have plenty of forward vision for planning ahead. Off road is another story as the uneven ground is hazardous and you often don't have too long to plan a relaxed, calm dismount when you're whizzing along twisty singletrack.

After studying the options available it became clear that virtually all SPD shoes are compatible with all SPD pedals as the relevant cleat is simply bolted to the underside using a standard bolt pattern. It seems that some shoes can be awkward to use with some pedals, especially if they have deep, rugged soles.

As the hunt for shoes only required a good fit to the foot, I focused on hunting down information on which pedals were available and it pretty much boiled down to two choices;
  • Shimano : Who had a miriad of pedal options from teeny race clips to big flat platforms, similar to those I'd been using but with the shoe retention system. Across the range they all seemed to have a tensioning system which means that whilst learning a low clamping force is applied for easy release. Once you're more familiar with dismounting with SPD's then you can increase the tension which also means that you'll be able to pedal with more conviction and not unclip unintentionally. The flip side to the tension adjust meant that cleat (the bit which fixes to the sole of your shoe) alignment was essentail as the mechanism doesn't provide much if any float and knee problems could result if poorly aligned. The Shimano pedals also had numerous moving parts with close tolerances which must work really well on the road but on muddy surfaces users reported that it was often difficult to clip back in once you'd walked around in the gloop.
  • Time : Who had a limited choice of pedals and no tension adjusters, which kept the pedals looking neat and simple. Without any adjustment they instead opted for a double sided cleat with one side requiring a lesser 13 degrees ankle twist to unclip and the other a more retentive 17 degrees. Their design also allows a few degrees of float which apparently helped to save the knees from a poorly adjusted, rigid clamping mechanism. The simple nature of the design means that tolerances aren't as tight and that they are much more mud friendly when compared to Shimano.
I decided to opt for Time's as I value my knees (afterall, I ride and don't run!) and I also figured that their robust simplicity would be better suited to offroad use. So which model should I choose ? I figured that something fairly basic would be a good start just in case I decided this SPD thang wasn't my cuppa, so I chose the ATAC (Auto Tension Adjustment Concept) Aliums. They aren't very light (at 1lb a pair) but they looked a fair balance of price and function. In use I initially found them easy to clip into (just dip your toe and press) but a devil to snap out of ! A few weeks of accumulating bruises gradually saw a technique emerge along with a crutial ability for the brain to automatically unclip when needed. Although I came close at one point, I did manage to stay out of the canal !

Over the years they've proven to be very reliable with my original set now having covered well over 4k miles without the need for a service. The bearings are still sweet and much to my amazement I haven't even needed to change the cleats which is fantastic as they're now used every week day on my commuter. I've been so happy with them that I even acquired a second set which have shrugged off many a pedal on rock strike. They also work brilliantly off road and you can happily walk through muddy sections and then just stamp the pedals when re-mounting and you're clipped in. No fuss.

More recently, CrankBros have introduced a range of SPD pedals which uses a mechanism very similiar to Time with the exception that they are typically lighter and smaller. The cleats are also very similar and allow riders to swap rides without having to swap pedals. Shimano cleats aren't interchangeable with either of these systems but I believe they are with Shimano-esque versions from say the likes of Ritchey, etc.

There are other SPD's available, which I'm sure other riders are happy with but the Time ATAC Aliums have been a solid performer for me. I've no regrets and I'd happily recommend them to others.

Update: With Chipmunk now seeking to use SPD's and my happy time with Time's (ahem) we've opted for the platform pedal called the Time Z. It provides a larger area to plant your foot if you don't want to clip in and are also sufficiently comfortable to use without cleats/bike shows so are ideal for the 5 minute jaunt down to the pub wearing trainers. However, whilst learning we intend to use some cheapo Shimano pedals with the adjustable tension as I found that Time's (although excellent) do require a great deal of commitment and a fair amount of strength to use initially - until they bed in and you get familiar with the technique.

Tuesday, June 14, 2005

SRAM vs Shimano

After recently making the transition from the "mainstream" Shimano gear shifts to SRAM I thought that I'd "spread the word" and give you the benefit of my experience.

I'm sure that almost everybody will be familiar with the Shimano amd it's MTB groupset with it's various levels of "competence" from the functional yet basic Deore, LX, XT up to the flag ship XTR. But how many of you know about SRAM ?

Background : Until a recently they were a small company building on it's slightly different take to the Shimano "standard" gear changes with different shifters, cassettes, chains. However, they're recently undergone few years of rapid expansion and are "the" company on a roll and are surely out to rival the bigS. They're moving towards being able to supply their own groupset after acquiring the likes of Avid (brakes) and Truvativ (cranks/stems/bars/seatposts/etc). More recently, they also bought out RockShox (forks, shox's) which is fairly big coo and give's them an edge to Shimano as they don't manufacture forks.

The SRAM gear sets range from X7, X9 to the major bling X0.

A number of basic differences separate SRAM from Shimano in the operation of gear changes.

  1. SRAM operate on a 1:1 ratio between the shifters and the mechs, whereas Shimano use 2:1 on the rear and 1:1 on the front. This means that a SRAM system is likely to operate for longer without the need for small adjustments and to be less prone to ghost shifts on full suspension steeds.
  2. SRAM shifter paddles are operated by the thumb only whereas Shimano require both the thumb and forefinger. This was a major selling point for me as having 4 fingers permenantly wrapped around the bars gives a more secure ride over those large boulders. It's also much less strain on the grey cells as only the thumb is in motion.
  3. The rear mech cable routing on SRAM is direct from the chainstay whereas Shimano need a long loop of cable to enter in the rear. The most obvious advantage of a direct cable run is less drag but an additional benefit is that shrubbery is less likely to get hooked along for a ride !
  4. SRAM rear mechs use a much firmer spring mechanism over Shimano. Which greatly reduces chain slap (chain hitting the chainstay), chain derailment when jumping and the mech hitting the chainstay. I can also be a pain to then get the back wheel out ! Update: checkout this thread for a video (approx 28Mb) that helps to highlight the differences.
SRAM also produce a Shimano range of compatible shifters called (rather uninspiringly) "2:1 shifters" ! Fortunately, they're more commonly referred to as Rocket or Attack.

Having previously used Shimano Deore and the midrange LX I can confirm that it's all good kit and works very well, with noticable improvements higher up the range. Converting to the SRAM midrange X9 shifters didn't cause any worries and in operation the changes are slightly less slick but feel more positive. Which I find a bonus when you've a set of full fingers gloves on as I always mis-shifted Shimano gears during the winter as their operation is quite light to the touch. Do they change any differently ? Probably but I'll be damned if I can tell. You'd need a dedicated test rig to figure that out and personally I'd prefer just to get out and ride...

Appart from the shifter ratio's all other components are interchangeable between the manufacturer's and my current rig has SRAM X9 shifters, rear mech and chain with a Shimano cassette and front mech. I've found that SRAM chain's tend to last longer but that probably means that the rest of drivetrain wears a little more rapdily.

The general understanding is that the SRAM front mech isn't as slick as Shimano, all Shimano cranks/bb's set the industry standard for light/stiff, that the top flight SRAM X0 rear mech is the bees-knees, that the SRAM X0 shifters are leagues ahead and that the rest of the kit functions on a par.

You chose which you'd like...

Share This...