FSA Gossamer 170mm Captain - Do they exist?
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FSA Gossamer 170mm Captain - Do they exist?
Searched through here.. looks like 170mm for the captain is next to impossible to locate. FSA website doesn't even list them. Bike fit says my body warrants 172.5's but my left knee protests. I completed DMD the previous weekend on my Tarmac with 170's, no pain at the knees over 200 miles, 20k climbing. We rode with Marco and Ruth up Mt. Diablo over the weekend and my left knee was not happy that evening. Swapping out to the new Shimano R601/603 would be quite expensive but at least I see 170mm is offered for captain and stoker. I asked Bryon at Crank 2 to see if he can locate a set of the Gossamers.
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I just found a set of NOS ISIS Gossamer front/captain cranks in 170mm after scouring the net and other sources for MegaEXO Gossamers front/captain cranks in 170mm and coming up with nada.
There are a few sets of Mega EXO SL-K front/captain cranks in 170mm out there on eBay and elsewhere, but they're not exactly value-priced.
I opted to go with the slight mismatch and better value of ISIS Gossamer vs Mega EXO SL-K.
BTW, I even attempted to see if I could flip a set of standard FSA Mega EXO Gossamer cranks for use on the front, only to discover that the axle on FSA's drive cranks is about 5mm shorter than the one they use on the tandem fronts.
There are a few sets of Mega EXO SL-K front/captain cranks in 170mm out there on eBay and elsewhere, but they're not exactly value-priced.
I opted to go with the slight mismatch and better value of ISIS Gossamer vs Mega EXO SL-K.
BTW, I even attempted to see if I could flip a set of standard FSA Mega EXO Gossamer cranks for use on the front, only to discover that the axle on FSA's drive cranks is about 5mm shorter than the one they use on the tandem fronts.
#3
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Maybe it is not the crank length but the difference in your fit and riding style on the Tarmac vs tandem.
I know I can have a tendency to push harder gears when climbing on the tandem.
I also stand more often on my single.
It would make sense to use whatever length you are comfortable with and have it the same on both bikes.
I stated off with SLK 170s and did not like the wide Q factor so I changed to standard Ultegra road cranks installed reversed and had the pedal threads helicoiled to reverse the threads.
I know I can have a tendency to push harder gears when climbing on the tandem.
I also stand more often on my single.
It would make sense to use whatever length you are comfortable with and have it the same on both bikes.
I stated off with SLK 170s and did not like the wide Q factor so I changed to standard Ultegra road cranks installed reversed and had the pedal threads helicoiled to reverse the threads.
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I also have 172.5 when I'd rather have 170. However that only increases our pedal circle by 5mm, about 3/16". What with the complex mechanics of leg motion, I don't think that's the problem. A tandem is just harder on your knees. I am just getting over a tandem knee issue which started on a 200k. Never would have happened on my single. Weight room, stretching, stepmill, and hiking is fixing it. About time I got back into that anyway.
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Pretty sure it's the crank length. I had a standard 53/39 172.5 on the Tarmac for a while and a 172.5 triple on my Pedal Force. Same pain in the left knee. I like the leverage of the 172.5's though I can spin up the 170's faster from a stop light. I will give it another month or so and see how things go.
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Pretty sure it's the crank length. I had a standard 53/39 172.5 on the Tarmac for a while and a 172.5 triple on my Pedal Force. Same pain in the left knee. I like the leverage of the 172.5's though I can spin up the 170's faster from a stop light. I will give it another month or so and see how things go.
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I would just get a standard double gossamer and do the helicoil.
That's your cheapest option, I think.
That's your cheapest option, I think.
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In theory, you'd think that would work but in practice it won't.
As I discovered last week, the Mega Exo primary / rear drive cranksets use a 127mm long fixed spindle, including the one spec'd for the tandem crankset.
Unfortunately, the Mega Exo tandem's front/captain cranks use a 132mm long fixed spindle, and the spindles don't appear to be something a user can swap-out.
I should have taken photos when I had the $89 NOS, Mega Exo 130 BDC Cyclocross FSA Gossamer cranks in my possession along side the tandem cross-over cranks, but was so bummed that it never occured to me. Heck, I didn't even need to do the Heli-Coils since we use Speedplay pedals: it would have been a pedal body swap and some Loctite.
If anyone does find a source for 170mm, Mega Exo Gossamer captain's cranks I'd be interested. As I said, I'm going to use a hybrid set-up on our triplet where the front & rear cranks will be Mega Exo and the middle position will be running the ISIS models. The bike came to us set-up with 170/172.5/175 and will now be 170/170/172.5. Ideally, it would be 170/170/170, but I'm pretty sure I can deal with 172.5 until I can find another set of 170mm ISIS or the illusive Mega Exo front cranks.
As I discovered last week, the Mega Exo primary / rear drive cranksets use a 127mm long fixed spindle, including the one spec'd for the tandem crankset.
Unfortunately, the Mega Exo tandem's front/captain cranks use a 132mm long fixed spindle, and the spindles don't appear to be something a user can swap-out.
I should have taken photos when I had the $89 NOS, Mega Exo 130 BDC Cyclocross FSA Gossamer cranks in my possession along side the tandem cross-over cranks, but was so bummed that it never occured to me. Heck, I didn't even need to do the Heli-Coils since we use Speedplay pedals: it would have been a pedal body swap and some Loctite.
If anyone does find a source for 170mm, Mega Exo Gossamer captain's cranks I'd be interested. As I said, I'm going to use a hybrid set-up on our triplet where the front & rear cranks will be Mega Exo and the middle position will be running the ISIS models. The bike came to us set-up with 170/172.5/175 and will now be 170/170/172.5. Ideally, it would be 170/170/170, but I'm pretty sure I can deal with 172.5 until I can find another set of 170mm ISIS or the illusive Mega Exo front cranks.
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170mm captain cranks came stock with my new 2006 Speedster. When I wanted to replace a right crank arm and could not find them I emailed FSA. The company informed me they made the decision to drop 170mm cranks from their product line and saw no reason to support prior customers with parts. In response I made the decision to drop FSA and converted to daVinci cranks. If a company does not support its customers or provide the product you want then do not buy from that company.
FSA stuff is ok and show up on new bikes because of their OEM pricing but I don't think they are anything special. There are other 170mm captain tandem cranks out there.
FSA stuff is ok and show up on new bikes because of their OEM pricing but I don't think they are anything special. There are other 170mm captain tandem cranks out there.
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In a perfect world where cost was no object, I would have clearly dumped the FSA cranks on the Triplet and replaced them with daVinci cranks... which is what we have on our other three tandems. I even considered canibalizing our Erickson and the Ventana for their cranks, but as a general rule try to avoid creating "hangar queens". So, at least for the time being and the upcoming rallies, the NOS ISIS 170mm Gossamers was the stop-gap solution.
As a general comment, all of the tandem builders and speciality dealers have been dealing with tandem crankset availability issues for several years. The volume of the tandem crankset buys is just so miniscule... which is why I'm still also a big fan and advocate of daVinci's "old school" square taper cranks. They meet all of our requirements for stiffness, appearance, durability, weight and available lengths / BCDs and finishes. Well, that and they're part of the tandem community and I'll always throw my business to tandem folks.
As a general comment, all of the tandem builders and speciality dealers have been dealing with tandem crankset availability issues for several years. The volume of the tandem crankset buys is just so miniscule... which is why I'm still also a big fan and advocate of daVinci's "old school" square taper cranks. They meet all of our requirements for stiffness, appearance, durability, weight and available lengths / BCDs and finishes. Well, that and they're part of the tandem community and I'll always throw my business to tandem folks.
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Interesting thread. I've been thinking of getting 165's for my wife on our daVinci and might be tempted to try her 170's on the front. My left knee will get a bit sore sometimes, result of a good deal of running into my 40's. It's difficult on the tandem, almost regardless of gear, to get into a completely comfortable spin. There always seems to be more effort to get over the top of the pedal stroke which I can feel in my quads. A shorter crank might help?
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In theory, you'd think that would work but in practice it won't.
As I discovered last week, the Mega Exo primary / rear drive cranksets use a 127mm long fixed spindle, including the one spec'd for the tandem crankset.
Unfortunately, the Mega Exo tandem's front/captain cranks use a 132mm long fixed spindle, and the spindles don't appear to be something a user can swap-out.
As I discovered last week, the Mega Exo primary / rear drive cranksets use a 127mm long fixed spindle, including the one spec'd for the tandem crankset.
Unfortunately, the Mega Exo tandem's front/captain cranks use a 132mm long fixed spindle, and the spindles don't appear to be something a user can swap-out.
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One-legged pedaling and weights might help. I wish I could throw down the bucks for a set of Powercranks for one of my singles.
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I also don't recall seeing anything different about the Mega Exo bearings used on the back set of cranks vs. the front two, but I may need to go and double check those tonight.
So, I dont' really have a hot clue why they're different, unless it was done to adjust the left-side chain line for the sync chain.
It's worth remembering that the front Mega Exo tandem cranks are flipped 180* from the normal Mega Exo crank, i.e., the spindle is fixed to the drive / right side on single and rear tandem cranksets whereas the spindle is fixed to the timing / left crankarm of a front tandem crankset.
That said, it did appear as though there was less material removed from the crankarm forging where the spindle was pressed-in on the front tandem cranks vs. two different sets of rear cranks that I was playing. This seemed to be the primary source of the different spindle length and that would move the left crank out a little more to line up with the rear timing ring. Again, I'll have to look at this again tonight just to satisfy my own curiosity.
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I have a set of 170 mm captain cranks sitting in a box, not being used. They are older Shimano 105-quality square taper cranks (model 1057 I believe). I bought them NOS a year or two ago to replace the 172.5mm FSA Gossamers on our tandem, and also bought the right length bottom bracket to get the chainline about the same as on the Gossamers. If anyone wants them (with BB) then PM me, but I would need to ship them from Switzerland.
I also just sold our complete set of FSA Gossamer tandem cranks, because for the moment we have been freed from needing tandem-specific cranks by using a Rohloff hub. Because we now only need one drive chainring, we can run a single-side drive and use normal cranksets; we can therefore use 165 mm cranks front and rear like we prefer (we're currently using a pair of Shimano 105 HTII 5603 models). However, the Rohloff isn't working out that well for us (it doesn't shift well under load, which is particularly a problem when riding OOP, which we prefer to), so we may revert to a normal derailleur setup. We'd then have to choose between skicking with the current cranks and single-side drive by running a super-compact double ring setup with something like a 28-44 chainring combo with the timing belt in the outer ring position. If we do decide that we need the top-end gearing of the triple setup (which I'm not sure that we do) then we'd buy a set of the Shimano R601/603 cranks in 170 mm lengths (plus a 42 tooth TA tripleizer ring to allow us to use a 26 or 28 tooth inner ring) and then we'd be back to having the timing belt on the non-drive side.
I also just sold our complete set of FSA Gossamer tandem cranks, because for the moment we have been freed from needing tandem-specific cranks by using a Rohloff hub. Because we now only need one drive chainring, we can run a single-side drive and use normal cranksets; we can therefore use 165 mm cranks front and rear like we prefer (we're currently using a pair of Shimano 105 HTII 5603 models). However, the Rohloff isn't working out that well for us (it doesn't shift well under load, which is particularly a problem when riding OOP, which we prefer to), so we may revert to a normal derailleur setup. We'd then have to choose between skicking with the current cranks and single-side drive by running a super-compact double ring setup with something like a 28-44 chainring combo with the timing belt in the outer ring position. If we do decide that we need the top-end gearing of the triple setup (which I'm not sure that we do) then we'd buy a set of the Shimano R601/603 cranks in 170 mm lengths (plus a 42 tooth TA tripleizer ring to allow us to use a 26 or 28 tooth inner ring) and then we'd be back to having the timing belt on the non-drive side.
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I had 175's on my tandem, they would pull my left ankle apart. The length makes a huge difference on your body. Also just read a study saying that the 175's only add 1.8% more power. I'd trade that for comfort any day.
I just bought an FSA 170 SLK Mega Exo with BB. The ad said it was made in 2011. Fits my co-mo beautifully.
Here's the ad https://www.ebay.com/itm/380448155595...84.m1423.l2649
I just bought an FSA 170 SLK Mega Exo with BB. The ad said it was made in 2011. Fits my co-mo beautifully.
Here's the ad https://www.ebay.com/itm/380448155595...84.m1423.l2649
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True, your left leg could be shorter, with the arm length accentuating the difference moving through a full circle. The shim would work better as a solid piece(s) between the cleat and shoe. Find shims at www.bikefit.com look for the leg length shims link in the left column.
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Last edited by aceSSone; 07-04-12 at 10:32 PM.
#19
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There seems to be some interest for shorter cranks on some single bike forums. Maybe the tandem cranks manufactures will bring back 170s. I went to 170 from 175 a few years ago and prefer the shorter cranks.