Crank Problems

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12/29/2008 6:32 PM

Okay, so I went out to ride today and my whole crank setup went to complete shit. My chainwheel had been loose the past few times I rode, but after I tightened the allen-bolt on the outside of the pedal it was fine.

[LINK TO IMAGE]
[LINK TO IMAGE]

Right after I started to ride, the left crank arm fell off completely. I wasn't too worried because ever since my bike was assembled, about three or four months ago, parts just oddly seem to become loose. I thought I had stripped my handlebars at one point, but double-checked the allen-bolts and they were loose to the point where I could adjust them with my fingers. I'm just guessing half-ass assembly on the part of the shop I took it to. I couldn't do it myself because I don't have the tools and I don't know bikes in and out yet. I checked out the setup and figured that the allen-bolt that clamps the crank arm down to the spindle must be loose.

[LINK TO IMAGE]
[LINK TO IMAGE]
[LINK TO IMAGE]
[LINK TO IMAGE]

I tightened it, along with the chainwheel again, and everything worked fine for about an hour. I was grinding a ledge (feeble) and then everything just went downhill. The pedal started falling off again and the allen-bolt to tighten down the chainwheel couldn't be tightened anymore by hand and without stripping it out. Also, the chainwheel became so loose to the point where the crank arm wouldn't even catch the chainwheel and it would freewheel pedaling forward.

[LINK TO IMAGE]
[LINK TO IMAGE]

I'm not too knowledgable about all the parts on real BMX bikes yet, as this is my first, so I was hoping for some input and advice (new/better parts, preventiong, assembly, etc.). It' was a stock three-piece crank, so I wasn't expecting a high quality product. I'm already anticipating having to drop some bones for a whole new crank setup, unless I'm a complete idiot and this is a quick fix. I need to find alternatives because I don't think I'll be taking my bike back to the shop where I had it assembled. Just hoping to get some pointers in this process. Thanks.

I have a 2009 Fit STR 1. Here are the stock specs straight off the Dan's Comp site where I ordered it. All I've changed is the chain.

Hi tensile steel frame with a chromoly toptube and no brake mounts or cable stops, standard 1-1/8" headtube, Fit fork w/ chromoly steerer tube, Fit bars, Fit grips, frontload alloy stem, 3-pc tubular chromoly cranks with sealed Mid BB, 25T chainwheel, 14mm front hub, 14mm sealed rear cassette hub with 9T driver, 36H Alienation PBR rims, Fit tires, KMC 410 chain and plastic platform pedals. 20" Toptube. (26.4 lbs)


http://www.danscomp.com/101975.php?cat=BIKES

Also, if the pics don't help, here's a video:

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12/29/2008 7:19 PM

i would dissasemble the bike completly and put it back togehtr right and fix any broken shit

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12/29/2008 7:42 PM

Would love to, but don't have all the tools, or the knowledge. There's only one shop around here that messes with BMX bikes and they're the ones I think slacked on the assembly in the first place. The only dude I know who I'd trust to assemble it for me doesn't even live in the same state as me anymore.

What crank setups would you recommend buying?

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12/29/2008 8:24 PM

if you bought it as complete then the cranks would have already been attached... so go check out that bmx shop...

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12/30/2008 1:38 AM
Edited Date/Time: 12/30/2008 1:39 AM

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blind eyes could look at me and see the truth

12/30/2008 1:39 AM

Yates wrote:

Would love to, but don't have all the tools, or the knowledge. There's only one shop around here that messes with BMX bikes and they're the ones I think slacked on the assembly in the first place. The only dude I know who I'd trust to assemble it for me doesn't even live in the same state as me anymore.

What crank setups would you recommend buying?

you already have a demolition bb kit so just get the demolition medial 2.0 cranks.. i love mine and there as simple as you can get when it comes to cranks

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blind eyes could look at me and see the truth

12/30/2008 11:21 AM

I think you're misunderstanding what I wrote.

The bike was already fully assembled, it just recently started to have these problems with the crank.

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12/30/2008 3:07 PM

Go get some tools that are common with building a bike, sit there and carelfully dissasemble the bike piece by peace remembering what you did 2 take the parts off for when u put them back on. If all else fails, carry allen tools in your pocket whenever yoiu ride,

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12/30/2008 5:56 PM

Yates wrote:

Would love to, but don't have all the tools, or the knowledge. There's only one shop around here that messes with BMX bikes and they're the ones I think slacked on the assembly in the first place. The only dude I know who I'd trust to assemble it for me doesn't even live in the same state as me anymore.

What crank setups would you recommend buying?

blaxuede wrote:

you already have a demolition bb kit so just get the demolition medial 2.0 cranks.. i love mine and there as simple as you can get when it comes to cranks

What specs would I need exactly? I don't know what it means when it's talking about mm's and such.

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12/30/2008 6:02 PM

the next time you get money buy twombolts or wombolts-theyre the best

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ukdthjctfukghcyr5eh

12/30/2008 6:03 PM

Yates wrote:

Would love to, but don't have all the tools, or the knowledge. There's only one shop around here that messes with BMX bikes and they're the ones I think slacked on the assembly in the first place. The only dude I know who I'd trust to assemble it for me doesn't even live in the same state as me anymore.

What crank setups would you recommend buying?

blaxuede wrote:

you already have a demolition bb kit so just get the demolition medial 2.0 cranks.. i love mine and there as simple as you can get when it comes to cranks

Yates wrote:

What specs would I need exactly? I don't know what it means when it's talking about mm's and such.

okay: 3-pc tubular chromoly cranks with sealed Mid BB
thats whats on your bike now
so if you buy cranks you need to get a mid bottom braket kit
for example:
if you buy this - http://www.danscomp.com/452550.php?cat=PARTS

you would need to buy this as well - http://www.danscomp.com/456007.php

you can tell if you need to buy a Bottom Bracket if when your on danscomp looking at cranks and it says : "Need a bottom bracket to complete your crankset?" then it has a link to it

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My nigga Ressler, stay up!
My nigga Babysatan, stay up!
My nigga Copiolet, stay up!
My nigga DakAttack, stay up!
My nigga NCDave, stay up!
My nigga Enzo, stay up!


And I ride for my niggas

12/30/2008 9:07 PM

When it has measurements from 145mm to 175mm, what is that referring to exactly?

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12/30/2008 9:08 PM
Edited Date/Time: 12/30/2008 9:08 PM

Yates wrote:

When it has measurements from 145mm to 175mm, what is that referring to exactly?

the length of the crank arm itself...most stock bikes are 175mm

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FI

12/30/2008 9:18 PM

Thanks. So it's more like a personal preference type thing? If I'm comfortable with how the stock crank is, I should just stick with 175mm, right?

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12/30/2008 9:30 PM

I'm considering these:

http://www.easternbikes.com/part/7/

What else would I need?

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12/31/2008 8:11 AM

Bump^

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12/31/2008 8:13 AM

Buy a DK Random Wrench V.2. It's the best $40 I've spent in a long time. You can take your entire bike apart with it and it's not much bigger than a seat post.

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12/31/2008 9:07 AM

Yates wrote:

I'm considering these:

http://www.easternbikes.com/part/7/

What else would I need?

u would need 19mm mid bottom braket bearings and everything would fit i had the same problem thats why i bought this how to book on bmx bikes or u can go to theshadowconspiracy.com and the have step by step instructions

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i like cake!!!!!!!!!!!!!!!!!!!!!!! 4shizzle

12/31/2008 10:05 AM

Yates wrote:

I'm considering these:

http://www.easternbikes.com/part/7/

What else would I need?

mr.530 wrote:

u would need 19mm mid bottom braket bearings and everything would fit i had the same problem thats why i bought this how to book on bmx bikes or u can go to theshadowconspiracy.com and the have step by step instructions

http://www.actionvillage.com/product/mapping/BkbAqAp.v3sAAAEd.8sutG2h

Like so?

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12/31/2008 10:08 AM
Edited Date/Time: 4/14/2016 6:02 PM

Actually,


This:


http://www.danscomp.com/...452511.php?cat=PARTS


And then just buy the BB set linked in the info?

--Sorry for double-post.

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12/31/2008 10:09 AM

i rode 180mm they are so nice.. i had a race bike with 145mm cranks and i was funny as hell

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"i forgive you and so does jesus"

12/31/2008 3:14 PM

So that Eastern crank (175mm), along with the linked BB set, will be fine? I just wanna make sure everything will be compatible before I buy it. Thanks.

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12/31/2008 9:09 PM

Yates wrote:

So that Eastern crank (175mm), along with the linked BB set, will be fine? I just wanna make sure everything will be compatible before I buy it. Thanks.

ya everything will fit

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i like cake!!!!!!!!!!!!!!!!!!!!!!! 4shizzle

1/1/2009 7:31 PM

Do I need to get a new BB set?

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