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I am looking at the compact 110mm cranks out there and am wondering if people using the ISIS crank/BB combo on the road are satisfied. My experiance with ISIS on my mountain bike was not good but those BB's took alot of abuse from my bash ring transfering impacts to the ISIS bearings. Do the ISIS bottom brackets hold up ok in road bike use?
 

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My dry bike has a FSA Ti Platinum Pro BB (ISIS) with 6K miles on it. No problems. I've used both the standard 39-53 and compact cranks on it. I think it's fine.
 

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JBF,

I personally prefer the ISIS to Mega Exo style cranks or Shimano (Octilink) BB. I have used all three and I think the ISIS gives the best combiniation of weight, stiffness, and cost at this moment.

IMO the ISIS spline is stiffer then Octalink and I'm sure there is some data that exists to that effect. An ISIS BB and crank are lighter on average then a crank with an integrated, external bearing BB. Obviously it depends on the components involved, but if you look at FSA for example: the SLK MegaExo weighs 848 grams (with BB) while the Carbon Pro Elite cranks weigh 515 grams. There are plenty of bottom brackets available that weigh less then the 333 gram difference.

I too was worried about the durability of ISIS, but I am yet to have a problem with it. I am a big guy and a 'masher' who replaced 2 Ultegra BB within the mileage my Truvative Gigapipe has lasted with no problems. I also have a new SLK Mega Exo and the crank spins like it is out of true. I have everything tensioned correctly and have put a true bar on it (it measures as being true) but it still spins with a wobble. IMO its because of play or deflection of the outboard bearings. I have heard of other users with the same problem. Also, my Carbon Pro Elite seems much stiffer to me then the SLK Exo. It could just be my imagination, however the fiber oreientation is much different.

If I were to buy right now and the prices were the same I would get ISIS. However, ISIS seems to be much cheaper so maybe the choice even easier.
 

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But it's a dry heat...
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JBF said:
I am looking at the compact 110mm cranks out there and am wondering if people using the ISIS crank/BB combo on the road are satisfied. My experiance with ISIS on my mountain bike was not good but those BB's took alot of abuse from my bash ring transfering impacts to the ISIS bearings. Do the ISIS bottom brackets hold up ok in road bike use?
You're right -- ISIS sucks big time on the MTB. I've gone through 3 Truvativ Gigapipe bottom brackets on my NRS in the past 2 years.

That said, ISIS seems to be a good choice on the road bike in dry conditions. Road bikes aren't subject the outrageous abuse that most MTB's are, so the smaller bearings should hold up fine on a road bike. Another weaknesses about ISIS bottom brackets was that the seals would allow water to enter and destroy the bearings. So if you ride in mainly dry conditions, ISIS should be fine on a road bike.

Thx...Doug
 

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Juanmoretime
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I've worn out two ISIS bottom brackets.

Both were the FSA Platinum Pro titanium version with the three bearings. I took over seven thousand miles for both and you can have new bearings pressed on by FSA or any bike shop with a bearing press. Considering I ride multiple bikes and for the weight I consider this very acceptable. I always keep a spare around anyway so when a bottom bracket goes bad, I just pop another in.
 

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But it's a dry heat...
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Juanmoretime said:
Both were the FSA Platinum Pro titanium version with the three bearings. I took over seven thousand miles for both and you can have new bearings pressed on by FSA or any bike shop with a bearing press. Considering I ride multiple bikes and for the weight I consider this very acceptable. I always keep a spare around anyway so when a bottom bracket goes bad, I just pop another in.
The Truvativ's that I wore out had less than 1K miles on them. The last one failed with about 200 miles on it (3 months), which is a joke. Of course, these were MTB miles, which are MUCH tougher than road miles...but regardless, it is still unacceptable. The 7yr old Race Face square taper BB in my old hardtail is still on its original bearings and smooth as ever.

I hear much better things about FSA ISIS BB's. I just switched my MTB to an FSA Platinum Pro Quad. The new road bike has an FSA Platinum Pro ISIS BB too. So far so good on both.

Thx...Doug
 

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I know there a bit heavier, but ry the MegaQuad...

MegaQuad Ti version is around 190g, but has 4 bearings and can take soem good abuse with large seals. I am trying one on the MTB in nasty conditions and so far after 5 months, still smooth as butta!
 
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