Calling all wanna-bee mechanics or the real thing: "crank extractor"

[kahn]

I brought my Creo to the shop and they did said they attached notes about what they did. I finally got to read those over yesterday. Here's an extract:

"The drive side crank extractor was missing. The washer was still present, though. The non-drive side was switched to the drive-side for convenience and the washer is in a bag. It should be kept for future use, if needed."

Can someone translate that to first grade, non-mechanic speak? Maybe a photo or image showing what is being discussed? Is that a part of fell off (unscrewed or loosened) or might not have been there in the first place? While I might ask the shop, snow, including two or three new inches overnight, is keeping me safely indoors other than getting a covid test yesterday and some basic shopping.

Happy New Year - well, soon.

 

[Stefan Mikes]

Happy New Year - well, soon.

The time is continous. I wish you all the best Fred NOW.

I cannot parse your mechanic's BS

 

[Stefan Mikes]

To be more clear. All SL e-bikes are similar. There is no "crank extractor" in SL e-bikes. All you need is a long 8 mm hex wrench. No idea what the mechanic has written.

 

[Prairie Dog]

I brought my Creo to the shop and they did said they attached notes about what they did. I finally got to read those over yesterday. Here's an extract:

"The drive side crank extractor was missing. The washer was still present, though. The non-drive side was switched to the drive-side for convenience and the washer is in a bag. It should be kept for future use, if needed."

Can someone translate that to first grade, non-mechanic speak? Maybe a photo or image showing what is being discussed? Is that a part of fell off (unscrewed or loosened) or might not have been there in the first place? While I might ask the shop, snow, including two or three new inches overnight, is keeping me safely indoors other than getting a covid test yesterday and some basic shopping.

Happy New Year - well, soon.

From what I understand, the bolt itself is the extractor. When turned the 8mm hex bolt pushes against the retaining ring and pulls the crank off the spindle. A better explanation is in the video link below. I simply don’t understand how the extractor bolt was missing from your bike though. Did someone else work on it in the past?

https://praxiscycles.com/product/m30-bolt-extractor/

 

[Jimbo08]

Creo crank arms use a self-extracting bolt that is specifically torqued. It can be tough to remove due to higher torque settings, and is a left hand thread. Before you fool around with it much more I would check back with your LBS about the 'spare' parts. As Mr Jones shows in the movie, depending on the brand some of these bolts do come in pieces, but without seeing it in person I cannot remember what the makeup of the Creo bolt is. I'd say your best to check with LBS.

 

[kahn]

From what I understand, the bolt itself is the extractor. When turned the 8mm hex bolt pushes against the retaining ring and pulls the crank off the spindle. A better explanation is in the video link below. I simply don’t understand how the extractor bolt was missing from your bike though. Did someone else work on it in the past?

https://praxiscycles.com/product/m30-bolt-extractor/

Well, only this shop has worked on the bike. I don't know if it was per-assembled by Specialized and how much the shop did. It went in for the 90 day workup after purchase. But I did not work on it and neither did anyone else. And the shop is quite large so any number of mechanics could have worked on it.

So, the question is maybe the write-up refers to that "retaining ring" rather than the extractor. Maybe it backed out and was missing? The "ring" that they returned to me is like a quarter (coin) size very thin washer. Thin in both its thickness (not very) and its diameter - like the raised edge on a coin, maybe a 1/16 of an inch if that. This is definitely a washer and not the retaining ring (no holes or indents or anything) - just a very thin spacer.

If the snow ever goes away I might head down there with the workup sheet and just ask.

Yeah, yeah, I know a little snow would not stop you

 

[Stefan Mikes]

kahn: Is your Creo OK or not?

 

[Prairie Dog]

The threaded retaining ring requires a splined cassette tool to remove it unless it was loose in the first place and worked itself out. It’s likely the shop was referring to the retaining ring as I can’t see how the bike could be ridden without the extractor bolt.


Is it safe to assume that both sides of the crank have the rings in place since the bike was returned to you?

Cold is one thing, but I’m pretty much helpless if the snow is too deep.

 

[m@Robertson]

What @Prairie Dog said is correct. Self-extracting cranks let you use a simple hex key to remove your crankarm without a specialty tool known as a 'crank puller'. Over the years, though, I have seen and had more than a few failures or glitches like @kahn has posted up. For that reason - if the crankarms use standard end caps and bolt threading (standard crank spindles use an uncommon fine thread for their metric bolts) I convert to standard crank bolts. Simpler can be better. Especially since the best crank puller on the market is under $20 and is very easy to use.

 

[kahn]

Well, only this shop has worked on the bike. I don't know if it was per-assembled by Specialized and how much the shop did. It went in for the 90 day workup after purchase. But I did not work on it and neither did anyone else. And the shop is quite large so any number of mechanics could have worked on it.

So, the question is maybe the write-up refers to that "retaining ring" rather than the extractor. Maybe it backed out and was missing? The "ring" that they returned to me is like a quarter (coin) size very thin washer. Thin in both its thickness (not very) and its diameter - like the raised edge on a coin, maybe a 1/16 of an inch if that.

If the snow ever goes away I might head down there with the workup sheet and just ask.

Yeah, yeah, I know a little snow would not stop you

kahn: Is your Creo OK or not?

I have not had a chance to use it since its "repair" so hopefully it is OK.

 

[Allan47.7339]

You could order a replacement but it's unlikely you would ever need it. When you order the carbon cranks to save a few grams they will have a new extractor.

It's a Praxis crank arm, their web page has an illustration for the bolt extractor:

https://praxiscycles.com/?product=m30-bolt-extractor

This is the reference to the extractor:

https://praxiscycles.com/product/alloy-ecranks/

This video shows how they remove the crank as part of removal of the battery and motor. They did not intended it as a "how to" but a demonstration of the steps a shop would go through. It appears there is no reason to remove the non-drive side crank for service unless replacing the crank arm.

 

[kahn]

You could order a replacement but it's unlikely you would ever need it. When you order the carbon cranks to save a few grams they will have a new extractor.

It's a Praxis crank arm, their web page has an illustration for the bolt extractor:

https://praxiscycles.com/?product=m30-bolt-extractor

This is the reference to the extractor:

https://praxiscycles.com/product/alloy-ecranks/

This video shows how they remove the crank as part of removal of the battery and motor. They did not intended it as a "how to" but a demonstration of the steps a shop would go through. It appears there is no reason to remove the non-drive side crank for service unless replacing the crank arm.

If I weren't so lazy (at the moment) I would take a picture of the washer. At the rate I add things to my kit and most recently fenders, shaving weight off the cranks is probably futile. But then again for every carbon fiber replacement I can shove something else in my kit!!!

Is the S-works Creo different than my aluminum model? I thought I saw a video where you only need to drop the motor housing to get at the battery. I did not realize you have to undo the crank also??? But after watching that video, too many screws/bolts. I'm not diving in!