Singlespeed & Fixed Gear - I done broke it...

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




View Full Version : I done broke it...


bleedingapple
07-20-10, 03:03 AM
So I was doing some maintenance on my bike today and found out that I ****ed up my crank set... I had to use a combo of rubber mallet external BB tool and vice grips to get if off my bike... It looks like I bent the axel of my Truvativ Elita external BB crank set. So much so that it exploded the bearings of one of the cups and was stuck to the axel. I mean my legs have ****ed up their share of bike parts in the past but I have never seen this... I mean I'm kinda proud too but **** I really liked that crank set and now I need a new one, so my new bike is on the shelf until I get one... sigh... :(

I'm kinda scared to used anything but my Omniums now seeing as I havent broken them, but I cant really swing for a new set let alone a black set to match my bike... This is why I was asking in the other thread what people thought of the Origin8 Propulsions vs. the Eighthinch crank set...


oldfixguy
07-20-10, 03:10 AM
I believe you. How many frames have you destroyed through punching holes in the BB shell with all that incredible leg strength?

LupinIII
07-20-10, 03:34 AM
obvious answer is that you need omniums, not the fact that you were trying to take off your grips with, among other things, a mallet and locking pliers


Squirrelli
07-20-10, 03:41 AM
Pictures of the aftermath would be appreciated.

Omniums are one of the stiffest track cranks around, I'd love to see a snapped Omnium.

f50fan
07-20-10, 04:58 AM
Reading this I pictured huge explosions and metal shrapnel flying everywhere.

Scrodzilla
07-20-10, 05:36 AM
So I was doing some maintenance on my bike today and found out that I ****ed up my crank set... I had to use a combo of rubber mallet external BB tool and vice grips to get if off my bike...

Why did you think that would be a good idea?

EssEllSee
07-20-10, 08:40 AM
How did this happen?

bleedingapple
07-20-10, 01:46 PM
I believe you. How many frames have you destroyed through punching holes in the BB shell with all that incredible leg strength?

No frames as of yet, thank god. I am always scared of it though... I have never ridden in 70+ GI, so I think that might have had something to do with it...


Reading this I pictured huge explosions and metal shrapnel flying everywhere.

They didnt fly everywhere but lots of little pieces came falling out...


Why did you think that would be a good idea?

I didnt think it was a good idea it was all I could do to get the crank set off... Left arm came right off no crank puller needed, then needed mallet to bang it through enough to use the BB tool to take the cup off. Pulled out the pieces of the cup that were left in the shell, then used vice grips to grab the drive side cup to get that out... Then needed a vice and a hammer and screw driver to get the rest of the cup off the crank set...

Held it up thinking the only way those cups could be stuck like that was it being bent, sure enough it was bent... still need to find the best way to measure it though...

spaceballs
07-20-10, 01:59 PM
So what actually broke? Was is the external bearing cups? I am not entirely sure, but I think the BB that comes with this crankset is the same as the BB that comes with the Omniums.

If the axle of the crankset is bent, I am not sure a different crankset would be any better. I have compared the axle of three different SRAM cranksets [Omniums, Rival, and s300s], and the axle looks pretty similar. I know the crankarms are made of different materials between the three different cranksets, but not sure if that applied to the axle.

For what I think you are describing to happen, I would think that there must have been some play in the crankset, BB, or a combination of both.

bleedingapple
07-20-10, 02:40 PM
So what actually broke? Was is the external bearing cups? I am not entirely sure, but I think the BB that comes with this crankset is the same as the BB that comes with the Omniums.

If the axle of the crankset is bent, I am not sure a different crankset would be any better. I have compared the axle of three different SRAM cranksets [Omniums, Rival, and s300s], and the axle looks pretty similar. I know the crankarms are made of different materials between the three different cranksets, but not sure if that applied to the axle.

For what I think you are describing to happen, I would think that there must have been some play in the crankset, BB, or a combination of both.

Yes the cups blew out... And as best I can tell the axel of the crank set itself is bent and thus the cups were stuck on it... I'm sure there must have been some play but nothing I noticed while riding... The fact that the left arm slid right off without needing a puller scares me... I know the look similar, I just wonder if the quality and machining is better? Funning thing is I was just talking to a coworker of mine the other other day about how he had broken the square taper right off his Phil BB for the 2nd time...

I'm really pissed though, was so happy to be riding my new wip, only other crank set I have is a cheap one I got in a used bin... Id rather not pull my Omniums off my other bike...

Anyone got some used black Omniums for sale? :p

spaceballs
07-20-10, 03:13 PM
The fact that the left arm slid right off without needing a puller scares me...

The left crankarm will extract itself as you unthread that bolt. Then the right side should slide right out. Should...

If you already have a set of Omniums, I would try to remove them from that bike. Then I would try to reinstall the suspected bent crankset into this BB. If it does install smoothly, then you can be pretty sure that the crankset is fine and the BB from the first bike was the culprit. Then you can replace the BB for $30 or so on the first bike and roll with the same crankset.

Tour sprinters ride cranksets of similar design and will push a lot more than 70 gear inches without bending their cranks.

adriano
07-20-10, 03:51 PM
no, you broke it.

cnnrmccloskey
07-20-10, 03:51 PM
If you already have a set of Omniums, I would try to remove them from that bike.

Please don't use vise grips

bleedingapple
07-20-10, 03:56 PM
The left crankarm will extract itself as you unthread that bolt. Then the right side should slide right out. Should...

If you already have a set of Omniums, I would try to remove them from that bike. Then I would try to reinstall the suspected bent crankset into this BB. If it does install smoothly, then you can be pretty sure that the crankset is fine and the BB from the first bike was the culprit. Then you can replace the BB for $30 or so on the first bike and roll with the same crankset.

Tour sprinters ride cranksets of similar design and will push a lot more than 70 gear inches without bending their cranks.

I know it should extract itself but this one comes off by hand, like i can slide it on as far as it will go and there is a very good amount of play and i can just pull it off by hand... My Omniums dont do this... I actually have an extra GXP BB but considering the left arm just flops around on the axel makes me not want to try it... Also it wasnt like this when I got the crank set, I had to use a puller to get the left arm off... I will at least try sliding on my extra BB and see if it gets stuck on there but riding it im not so sure about...

bleedingapple
07-20-10, 04:16 PM
So I tested the new cups on the crank set and they get stuck on the drive side, another thing my omniums dont do...

Leukybear
07-20-10, 05:26 PM
Wowwwwwww... fail. And to think there's a simple and cheap bike tool that does it for you painlessly....

spaceballs
07-20-10, 05:49 PM
So I tested the new cups on the crank set and they get stuck on the drive side, another thing my omniums dont do...
You cannot screw in the BB cup on the drive side of the first bike? The drive side is reverse threaded...

I don't know how you would even use a crank puller here.

bleedingapple
07-20-10, 05:49 PM
Wowwwwwww... fail. And to think there's a simple and cheap bike tool that does it for you painlessly....

I used the BB tool to get the non drive cup off, but since the axel of the crank was stuck in the drive cup I had to used the vice grips to grab the BB cup and unthread it since the BB tool doesn't fit around the crank spider... I have the tools and know how to use them... :notamused: