Dicky DQ Posted January 13, 2009 Posted January 13, 2009 What is the deal with the FSA Carbon Cranks that have shipped with the team carbon bikes for past 2 years? they seem to have a habit of comming loose on thier own and destroying the BB in the process. Mine keeps doing this. I heard that the cranks were replaced under warranty some time back, but seeing as I tried to make the best of a bad situation it appears as if i have shot myself in the foot. Is this a common problem or not.
Groot Lem Posted January 13, 2009 Posted January 13, 2009 ping, help please. i dont want to push my epic partner at attakwas, Dick weigh like 100k's .
chatterbox Posted January 13, 2009 Posted January 13, 2009 Get hold of the FSA agents , they replaced my carbon cranks without hesitation. They have really picked up their game . One more reason for supporting local Suppliers
vanniri Posted January 13, 2009 Posted January 13, 2009 Just bought a team Merida - OOPS!Seriously - here in Salvador, Brazil a large number (at least 8 from the last three years) of serious cyclist are riding the Merida Team (reason I bought one since I know after service would be good). All have FSA cranks and not a single one has mention such a problem to me. Will ask them this week-end, also check my bike tonight. Exactly what should I be looking for? The bolt on the non-drive side becoming loose?
turtlek Posted January 13, 2009 Posted January 13, 2009 you might be the lucky one to not have that problem unfortunately my buddy had his come loose while in the lead group of the 94.7 last year (yes road bike but it is the first time in three years that it happened) and it is not the first i have heard but give emotion cycling a call they wont hesitate to offer a solution if it happens
Johan Bornman Posted January 13, 2009 Posted January 13, 2009 Are these one-piece cranks or do they attach to a separate BB axle? Is it a spline-fit on both sides?
Dicky DQ Posted January 14, 2009 Author Posted January 14, 2009 JB Not sure what you mean by 1 piece. The drive side has a hollow shaft that goes through the BB and has a straight spline on the non drive side. The non drive side cranck then gets pulled up against the BB to fasten. This seems ok for a while, but as soon as there is the slightest wear on the BB nut seems to work itself loose. then after time and riding with the loose crank (what to do in a marathon half way out) the spline seems to wear and then even if the nut is fastend correctly there ise still fore and aft play due to the wear on the spline. This, apart from being a big irritation, causes the nut to come loose as well. And the cycle begins again. I had the BB replaced last week and everything checked etc. Then 20km into the mountains the same thing happend all over again.
Johan Bornman Posted January 14, 2009 Posted January 14, 2009 JB Not sure what you mean by 1 piece. The drive side has a hollow shaft that goes through the BB and has a straight spline on the non drive side. The non drive side cranck then gets pulled up against the BB to fasten. OK' date=' this is a one-piece crank. Confusing, since it is actually two pieces but I don't make up the terminology. This seems ok for a while, but as soon as there is the slightest wear on the BB nut seems to work itself loose. What do you mean by wear on the BB and what is the BB nut? then after time and riding with the loose crank (what to do in a marathon half way out) the spline seems to wear and then even if the nut is fastend correctly there ise still fore and aft play due to the wear on the spline. This' date=' apart from being a big irritation, causes the nut to come loose as well. [/quote'] I'm still confused, on the left hand side, the left crank attaches to the BB axle via splines and is locked in place by two pinch bolts. Is this what you mean by BB nut? If I assume correctly, the two pinch bolts are coming loose on the LHS. You right about the crank then being ruined. Once the splines are damaged, even just from riding 10 kms softly, they are irrepairable and the crank is ruined. But lets first establish if we are talking about the pinch bolts. Are they like these black ones in the picture? The other one is hidden on the other side.
turtlek Posted January 14, 2009 Posted January 14, 2009 ok johan the only difference is that the FSA cranks fasten t othe crank via the old style bot into crank ala shimano hollowtech 1 style but only on one side and has a similar diameter bolt to the hollowtech bolt so instead of the fancy tool needed to fasten the crank arm on to the axle and then using pinch bolts you only need an 8mm allen keyturtlek2009-01-14 04:20:01
Johan Bornman Posted January 14, 2009 Posted January 14, 2009 Turtlek, you make my head spin. Hollowtech is a Shimano trade name for hollow cranks. Hollow BB axles are just, well, hollow BB axles. But I get what you say. OK, now that I know what the problem is, here's the answer. It's a rubbish design and suffers from the same problems as the Shimano Octalink (search for it, I've written quite a bit about the faults in that design). The crank should be a tight press-fit and it isn't, which means it has lash. Lash is like backlash when you get rear-ended in your car. Imagine the same movement in the splines. Visualise the splines on the crank being made from rubber and you now standing on the cranks, off the saddle. You'll see that the crank moves in relation to the BB axle. If you are standing with your left leg facing forwards and your right leg rearwards (goofy), then the movement of the crank on the axle will cause the bolt to loosen. If you can't visualise this, then imagine the bolt head being stuck to the crank and the crank moving on the axle. Now imagine that bolt head having a ratchet in there and with two or three hard bumps whilst you stand on the cranks, the bolt has loosened enough to give the splines open lash and bang, your crank is ruined. I've seen this on Octalink, Truvative and you have now reported it on FSA as well. It is a poor design abandoned by Shimano and never adopted by Campagnolo for very good reason. On the Truvativ design the bolt can bottom out, preventing you from tightening it enough. I haven't examined the FSA but do it yourself. See if the bolt can go in deep enough to make the fit tight in the first place. A new crank should have a very tight press fit and you should not be able to just press it into position by hand. That's the sign of a ruined crank or manufacturer's fault. Either way, keep on asking the manufacturer to replace it until they become tired or bancrupt and then adopt a decent design. I suspect they don't want to pay licese fees to Shimano or Campagnologo and haven't come up with their own method of fixture yet. Johan Bornman2009-01-14 04:47:04
turtlek Posted January 14, 2009 Posted January 14, 2009 hahaha sorry johan reply was done in haste as i am busy at work today!!
TNT1 Posted January 14, 2009 Posted January 14, 2009 hahaha sorry johan reply was done in haste as i am busy at work today!! ? Schools back in... who's skating now?
turtlek Posted January 14, 2009 Posted January 14, 2009 hahaha sorry johan reply was done in haste as i am busy at work today!!? Schools back in... who's skating now? nobody thats the problem now we cleaning up the mess of all our casuals we had to hire over the holidays
fandacious Posted January 14, 2009 Posted January 14, 2009 You guys got a Zamboni? which self respecting ice ring doesnt? whats the alternative? get on your hands and knees and do it? no thanks
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