Bicycle Mechanics - Problems removing Bontrager race crank (isis style)

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vtsteevo
01-18-10, 06:55 PM
Hi all,

My bontrager race cranks creaks on every single turn of the pedal, so I'd like to remove the crank, re-grease and re-assemble. I removed the 8mm bolts on the crank, and now I am trying to remove the crank from the isis bottom bracket.

This is the tool that I have: Nashbar crank extractor.
http://www.nashbar.com/bikes//Product_10053_10052_124649_-1___

I first unscrewed the outer part all the way, then I screwed it into the crank by hand until I could no loonger it it in there by hand. Then I started to turn the tool clockwise driving it into the crank. I kept turning it, and it is as tight as it can get, and it won't extract. I feel that I've applied more then enough pressure to remove any type of bolt known to man, and this thing still won't come off. I am guessing by the fact that it won't move it means that the stopper on crank extractor won't let the exractor in anymore.

So what am I doing wrong? do I have the wrong tool? Per nashbar this works with Isis BBs. P.S. i've found similar posts but with no resolution.

thanks,
-steve

Bike: 2002 Gary Fisher Sugar 2 with Bontrager Race Crank and Bontrager Isis Bottom Bracket


reptilezs
01-18-10, 07:40 PM
you need the big stopper piece that goes on the tip of the extractor.

operator
01-18-10, 07:43 PM
you need the big stopper piece that goes on the tip of the extractor.

And I might also add, you're supposed to use a *wrench* to tighten the extractor fully into the crank extractor threads. Not just hand tight.


reptilezs
01-18-10, 09:26 PM
made this vid a while ago http://www.youtube.com/watch?v=J6Bv70B545U

MudPie
01-18-10, 10:51 PM
Make sure there is not a washer in the crank arm to crank bolt interface.

Soil_Sampler
01-18-10, 11:17 PM
see if your lbs has a few of these FSA extractor buttons laying around.

http://www.fullspeedahead.com/imagefly.aspx?p=productimages%2fcopy%5b1%5d_BB_ISIS_ExtractorTool.jpg&w=326&h=326

operator
01-18-10, 11:22 PM
see if your lbs has a few of these FSA extractor buttons laying around.

http://www.fullspeedahead.com/imagefly.aspx?p=productimages%2fcopy%5b1%5d_BB_ISIS_ExtractorTool.jpg&w=326&h=326

His extractor should already come with an ISIS compatible tip.

Soil_Sampler
01-18-10, 11:41 PM
must come with two.
description and pix don't match.

joejack951
01-19-10, 07:16 AM
ISIS cranks do take a lot of force to extract. However, make sure you have the right tool and no washer in the way first as recommended above before you go nuts with the extractor.

vtsteevo
01-19-10, 11:01 AM
Thanks for the replies. I will check for the washer when I get home this evening, but I am 99% sure I pulled the washer off when I removed the crank bolt. There was a thick washer attached to the bolt on both sides.

Will take pics/vid tonight of the tool. I am pretty sure I have the correct tool.
-Steve

vtsteevo
01-19-10, 05:24 PM
Looks like I have the right tool, and I am using the fat lip thats in the picture. There is also no washer in there. Frusturated, I took the bike to the local shop and the guy tried to use my tool in front of me and could not get it off. When we removed the tool we found that the fat lip was stuck in the bottom bracket (it went through the hole that it was supposed to push against). After removing it with a srewdriver/hammer we tried using the shop's Park tool designed specifically for ISIS style BBs. Same thing, the tool got stuck in there pretty good, and we had to hammer it out. The guy had to leave so we will pick this up again Thursday evening. I may just replace the BB because its creeking like there's no tomorrow but most important, I should be able to remove a crank trail side if I ever need to without this much effort!

Will update on Thursday..
-Steve

Soil_Sampler
01-19-10, 06:02 PM
Is this a 2pc crankset, with an Isis spline on one side?

With a self extractor bolt?

http://www.bike-manual.com/brands/bontrager/om/BT/self-extractor-parts.gif

WNG
01-19-10, 07:11 PM
Try placing a nickel or other flat steel disc as a 'plug' before installing the extractor. This will prevent the tip to deform and press into the hole.

vtsteevo
01-25-10, 08:13 AM
Well, it was the washer. It was jammed in there so much that it looked like it was part of the threading. The nickel did the trick of helping get the crank arm off, and then we got the washer out with a screwdriver and a hammer.

We put on the Truvativ Giga Pipe Team SL BB, which came with its own set of crank bolts. The washer was pre-mounted and attached to the crank bolts, so I will not have this problem anymore!

MudPie
01-25-10, 09:18 AM
I wrecked a tool because of that dang washer (back in the mid 80's, pre Internet days). Remember, experience is our best teacher!