Replacing ISIS cranks

Lumen

For the short of patience, the question is at the end...

My right achilles is sore and a bit swollen. The most obvious cause is that I've increased the saddle height by too much too quickly, and done too much distance and climbing too soon. Commuting on a SS probably doesn't help either.

With only a few weeks to go until WW200, I'm really scared of picking up a long running injury.

So I've put the saddle back where it was, and moved the cleats all the way back, and plan to stay off the bike this week at least until the pain and swelling has gone.

However...

Reading up on achilles problems, it seems that both high and low saddle positions can cause problems in the calf area, overstretching at either the top or the bottom of the pedal stroke.

I'm currently running a 175mm Truvativ Elita Triple crankset. Given my shortish legs, I'd normally opt for 172.5mm, but Sheldon reckons there is no issue with shorter cranks (particularly since I've a triple so don't need the leverage), so I might consider 170mm or shorter.

I believe the Elita are ISIS cranks which should make it easy to swap, but I can't find cranks for sale on their own, and I really don't want to replace the whole chainset. I don't know whether the ISIS compatibility concerns the spider dimensions or just the splines.

Anyone know the best place to buy just the cranks?

penexpers

ISIS refers to the bottom bracket, nothing to do with spiders/splines. You should be able to replace the crank arm with any crank arm/spider that has an equivalent BCD.

niceonetom

penexpers wrote: »

ISIS refers to the bottom bracket, nothing to do with spiders/splines. You should be able to replace the crank arm with any crank arm/spider that has an equivalent BCD.

Spiders? No. Splines? Very much yes. It would still need to be an ISIS splined crank to use the same BB which I think is the question... is it?

Lumen- so you want new cranks, but you would rather not change the BB or the rings?

BCD relates to what chainrings will fit on the crank arm spider. ISIS relates to what BB the spider will fit on. Not sure what cranks you're rubbing at the moment but they are almost certainly either 110 BCD or 130BCD. 100 is compact, 130 is full size.

I don't actually know where the best place to get just the cranks alone is, but are you really sure that 2.5mm of the crank is the issue? You said you've moved your cleats back - I did the same a while ago and very quickly found that I was using my achilles less and not getting as much calf strain as I was before. Moving the cleats back necessitates lowering the saddle to maintain the same pedal stroke - so if you've put your saddle back to it's original height and moved your cleats back you have effectively extended your pedal action.

It is against local policy to dissuade each other from shopping, but this sounds more like a set up issue than a reason to get the credit card out again...

blorg

I also suspect it is a setup issue and you don't need to change the cranks.

The Truvativ Elita on that bike are outboard bearing GXP cranks, e.g. integrated spindle with the BB just being cups. They are not ISIS, that is an older system. If you must, any Truvativ or SRAM GXP crank should fit without your having to change the cups.

short circuit

I had the exact same problem ... but in my case it was brought about by sitting on my ass for a week .. and then doing a 5k run and 120k ride on the same day.

Ended up needing a couple of sessions with Paul Tansey and a week off the bike.

Only solution is move the cleats as far back as possible ... I've also heard some brands allow for more of this than others .. so trying another pair of shoes might be an idea. It also has a close bearing on if your toes are pointing downwards at the bottom of the pedal stroke .. and hence moving cleats backwards stops you from doing this.

The only reason to go for a smaller crank would be if you find yourself mashing a lot ... in which case a smaller crank will encourage spinning .. otherwise I reckon the difference between crank sizes is fairly small.

sy

Lumen wrote: »

My right achilles is sore and a bit swollen. The most obvious cause is that I've increased the saddle height by too much too quickly

Take great care with this injury Lumen. An insert in your everyday footware to raise your heel is important and ice regularly. Most physios will friction the sore spot to stimulate the circulation( tendons have very poor circulation) and you can do this yourself. It will hurt like hell but an ice cube, rubbed continuously on the spot as it melts:) is good. Rest for the week and start stretching the tendon over the next few days. I'm not a phsio! but have had this problem a few times from pushing too big a gear too soon in the season. Apologies if you already know the details and I realise you haven't asked for advice but be patient and good luck with the recovery.

Lumen

Thanks for all the advice. For now I'll keep the saddle low and consult a physio about heel inserts.

short circuit

Lumen wrote: »

Thanks for all the advice. For now I'll keep the saddle low and consult a physio about heel inserts.

OK .. I should be the last person to advise you against visiting a physio ... but I can post my experience.

When Paul Tansey was treating my achilles, he said I needed custom soles .. it was going to cost around 250 - 300 euro for the 1st time .. and then around 70 euro if ever needed again. I have flat feet .. I knew .. but never had any achilles problem before.

I got these ... which are cheaper .. but can still be moulded ...
http://www.irishfit.eu/sole.html

I mostly use them for running .. and I have noticed a huge increase in comfort ... and might be something to try out before you go total custom route ...

I know ... no compromise with health and all ... but these came recommended in Runner's world magazine.

Also ... a full foot sole is better than just heel inserts ... the heel inserts just keep slipping when you walk ... or maybe I was just using them incorrectly.

Halfrauds

That sucks dude:(

maybe instead of replacing the cranks, you should replace the frame, sounds like it isnt great fit for you, the geometry could be not the best for ya:(, no point in throwing money at components hoping that it will solve the problem.

Lumen

@short circuit....

I saw IrishFit for my gait analysis. They said there's nothing wrong with my feet (e.g. arches are fine), I'm just inflexible which when combined with slightly weak core and overtraining tends to cause problems. They suggested orthotics could help the symptoms, but that it was better to get at the root of the problem.

So I've started yoga to improve flexibility and core, but it's a slow process.

I seem to be going from one injury to another right now. I decided to start running to give me something to do on rest days...and injured my plantar fascia. So to keep the strain off my feet (4 km walking to work) I started commuting on the singlespeed, which has probably helped to aggravate my tendons.

At this rate I'll have to bloody drive to work. Or swim.