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Discussion Starter · #1 ·
Im in need of some info about replacing my bottom bracket..well actually the whole crank set. My IFS crank is creaking very badly and no amount of bolt tightening would fix it so im just gonna replace the whole thing with a new crank/bb set from pricepoint.

My questions are, can i use a makeshift tool to get my old BB off or do i NEED to get the special tool for it? Dont worry ill be using the right tools to put on my new BB but i rly dont wanna spend $12 or so on a tool im only gonna use once.

Here are some pics of my BB:





Second question is, how do i find out what BB's are compatible with my bike? Is there a universal size? I see abbreviations being thrown around like ISISI and others but dont rly know what they mean. Any help on that would be fantastic.

This is the crank set im wanting to buy, would it be compatible with my bike?
crank: http://www.pricepoint.com/detail.htm?stylepkey=13968
my bike: http://www.bikesdirect.com/products/motobecane/fantomtrail_ds08.htm

Thank you. :)
 

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You'll need a splined bottom bracket tool to get you bottom bracket off. No makeshift tool will work. That crankset will be compatable w/ your bike but it's a bit on the hefty side.....why not get the evolve XC? Keep in mind, while removing your crank the drive side BB cup is reverse threaded......turn to the right to loosen. Non-drive side is normal (turn to the left to loosen).
 

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Discussion Starter · #3 ·
JSumner13 said:
You'll need a splined bottom bracket tool to get you bottom bracket off. No makeshift tool will work. That crankset will be compatable w/ your bike but it's a bit on the hefty side.....why not try the evolve XC?
Honestly weight dosent really bother me but if i can save some i will. I wanted the Race Face Evolve DH because it had 22/32 tooth combo, it was on sale, it had a bash guard, and came with a BB.

I do a mix of road riding and free ride/dh riding so i use the 22t ring quite a bit and would hate not having it for those steep slow climbs.

If there is a lighter crank that came with 22/32 rings, bash guard/bb combo, and for that price i would buy it.
 

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Creaking does not mean that you need a new BB. Is it running rough? Is it loose when grab the crank arms and try an move them laterally?

If not, then the BB is fine. Buy a BB tool or get your LBS to remove, clean, grease and re-install to trouble shoot the creak.

I think your BB is a ISIS spline and I read here on MTBR that ISIS is good, but will always eventually creak. Anyone want to confirm this?




You will need a different tool for the External BB that comes with your cranks.



and you may need this
 

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Old man on a bike
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First, your question about what bottom brackets fit your bike. The bb is more about fitting the crank, but the bike's bottom bracket shell width does determine either the specific bottom bracket or the number of spacers to use with one that's for the two normal widths found on mountain bikes (68mm or 73mm). Your link doesn't tell me what width your bb shell is but just take a ruler to the bottom of your shell and measure it, it's one or the other.

There are several different systems for bottom bracket/crank, square taper, ISIS, Octalink and the external bb type (and within the external camp there's a few differences to watch out for). I can't tell which your bike has, the link mentions in the "features" area that it's a FSA Dyna Drive, which is a square taper, but in the specs in the boxes below "shipping now" it says it's a Power Drive, which is an ISIS type. They (the ISIS or square taper FSA cranks) use the same tool to get the bottom bracket out, as was already mentioned, but slightly different crank pullers to get the arms off (unless they have self-extracting bolts, and the crank puller tool like the bottom bracket tool wouldn't be of any use with an external type crank).

I think you're in for an expensive habit if you buy a whole new crank when it creaks. Unless you're getting a lot of play or your rings are toast, I'd service the current one first. Take the bottom bracket out of the frame and make sure both the frame and bb threads are nice and clean and greased and then reinstall it back to spec, which means torquing the bottom bracket and arms to spec (using a torque wrench). More than likely that will get rid of the creak.

Otherwise that new crank you're picking is a bit porky to just lose a chainring. I'd get the Shimano LX for $99 at Jenson if you want a new external type bb/crank (3-ring, no bash, though). It might make sense for a true fr/dh rig to get a dh crank, but you don't have a fr/dh bike (hope you're not doing serious fr/dh type riding on that bike). You could just buy a bash ring and install it in place of a big ring, too.

You'll need to readjust the front derailleur which ever way choose to lose your big ring.
 

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i think its a octalink crank. isis bbs dont usually look like that. uses the standard 20t cartridge bb tool as posted previously
 

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Discussion Starter · #7 ·
I'm positive my bb is not the cause of my creaking, the creaking is comming from the crank bolts. No matter how much I tighten them they just keep craking, I stripped half the bolts in the process lol.

When I decided to get a new crank I initially wanted to just leave the BB, but I didn't find any cranks that I liked which were compatible with the fsa BB I had. So I just decided to replace the crank and BBC together so I wouldent run the risk of incompatability.

I've got to leave for work now so...tbc lol
 

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eliassami5 said:
I'm positive my bb is not the cause of my creaking, the creaking is comming from the crank bolts. No matter how much I tighten them they just keep craking, I stripped half the bolts in the process lol.

When I decided to get a new crank I initially wanted to just leave the BB, but I didn't find any cranks that I liked which were compatible with the fsa BB I had. So I just decided to replace the crank and BBC together so I wouldent run the risk of incompatability.

I've got to leave for work now so...tbc lol
Creaks can be deceiving...how are you so sure it's the bolts? You mean where they thread into the bottom bracket or the interface with the crank arms? Have you used grease on those interfaces? Have you ever made sure the cups of the bb are tightened to spec? I'm guessing you don't have a torque wrench, though.
 

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Discussion Starter · #9 ·
Bikinfoolferlife said:
Creaks can be deceiving...how are you so sure it's the bolts? You mean where they thread into the bottom bracket or the interface with the crank arms? Have you used grease on those interfaces? Have you ever made sure the cups of the bb are tightened to spec? I'm guessing you don't have a torque wrench, though.
Yes I've got a torque wrench and any other tool I might need, my dad used to be a mechanic. The bolts I am refferin to are the ones that secure together the different size cogs, not the main bolt that tighten the crank ams.
I know this because I had tightened them once before and the creaking went away for a while and then came back.
 

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eliassami5 said:
Yes I've got a torque wrench and any other tool I might need, my dad used to be a mechanic. The bolts I am refferin to are the ones that secure together the different size cogs, not the main bolt that tighten the crank ams.
I know this because I had tightened them once before and the creaking went away for a while and then came back.
So what did you torque the chainring bolts to? Did you take them apart, clean them and grease them first? Not saying it's not possible, but in all the cranks I've had, that's just not much of an issue...
 

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Killroy said:
I think your BB is a ISIS spline and I read here on MTBR that ISIS is good, but will always eventually creak. Anyone want to confirm this?
This looks like a FSA Platinum series ISIS BB to me. The FSA style splines (definitely a proper tool is required), the fat, gray colored axle, and the blue seal kind of give it away. I've got 2 FSA Platinum ISIS BBs right here, they look the same. I may be mistaken of course.

As to whether ISIS is good, I'd say that not all is well with it. First there's too little room for bearings, which leads to many failure modes and all sorts of hacks that attempt to delay or circumvent the problems. Then it's a press fit arrangement.

My favorite in BBs is the Hollowtech 2 standard - it very elegantly sidesteps both of the above issues all the while staying compatible with the most established BB shell standard.

Edit:
as for the chainring bolts, it's a good idea to threadlock them.
 

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Discussion Starter · #12 ·
Bikinfoolferlife said:
So what did you torque the chainring bolts to? Did you take them apart, clean them and grease them first? Not saying it's not possible, but in all the cranks I've had, that's just not much of an issue...
I removed the crank bolts and greased them and put them back on, i tightened them as much as i could with ought stripping the bolts, i didnt use a torque wrench to tighten the bolts.
 
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