Crank Bros. refurb

bod

Old School Hero
It's been a while since I've hung out on retrobike but I just bought some slightly knackered but lovely RSRs and more recently a 94 Explosif frame. I only planned to get my 98 Explosif up and running so my girlfriend could ride trails around the New Forest and hopefully the South Downs but I'm sure you know how these things go…

I've also managed to break arm pretty well a couple of weeks ago which means I've had way too much time on my hands. You'll need to bear with me, I need to take strong pain killers to cope with the pain so I might be a bit confusing. Feel free to call me on anything!

Anyway, there seems to be a lack of info on CBR dog bones so hopefully I'll collate some of the info I've been struggling to find.

First of all, taking them apart; I read the usual "it's impossible, you'll die" rubbish on several forums. I was lucky because two of the pins on the back of the spider were already working their way to freedom. I managed to pry them out quite easily. The third's head was below the edge of the spider so I just undid the bolt and hit it with a (nylon) hammer. While the bolt seemed a bit rounded no Allen keys I had seemed to fit but an imperial key worked well enough to undo it. It looks standard so I'll source a new one that's 5 or 6 mill. Even with a broken arm it was easy.

The pins have a helix on them but they don't seem reluctant to come out. Once it was all apart it seems the spider and pins were glued together. The glue (if it is glue), which is now dark beige, peels off easily. I guess it's an epoxy, I've seen this kind of stuff on old aircraft parts but I could easily be wrong though. If it was glued together then the glue has long given up its purpose.

Hopefully this works, I remember having a hell of a time posting pictures here. Don't worry though, you won't have to see that yawning f*****g kitten!
RmMG6n


Next step is getting them reannodised. I'll sand the worst out but leave the big divots in. Hopefully polishing them as much as I can will reduce the cost of annodising. There's a few big dents that I can't get rid of so I'll live with those. I need to check how the stripping will affect the tapers and threads and then get the logo laser etched again. I think these will be the biggest obstacle.
 
bod":x0zqkvc5 said:
Bloody hell, can someone tell me how to post pictures here please?

You need to use a host site such as photobucket.com.
Upload the pics, then copy the link info next to or below the hosted image.
Click "img" at the top of the "Post a reply" (you have to use the full version not quick reply), hey presto image in your post.
 
bod":33w6yl1z said:
Bloody hell, can someone tell me how to post pictures here please?


You can download a picture resizer, they are free. You then right click on any photo on your computer and it gives you the option to resize image. You then just attach image using the box below your message reply box :)

Mark
 
resize - use MSPaint - there is option to resize; choose percentage to give 604 px horizontally and then post via this web site.
 
bod":oz18gevr said:
Next step is getting them reannodised. I'll sand the worst out but leave the big divots in. Hopefully polishing them as much as I can will reduce the cost of annodising. There's a few big dents that I can't get rid of so I'll live with those. I need to check how the stripping will affect the tapers and threads and then get the logo laser etched again. I think these will be the biggest obstacle.

I think the bolts are imperial.
Stripping will affect the threads and tapers if you don't know know what you are doing.
You can anodize them with the spider attached, although they are different grades of aluminium so the spider may look a different shade to the cranks.
I've anodised the logo's on these cranks before, but never again. I can blast the logo's on though, it'll look similar to the origionals.
 
Thanks guys. Well, that's that then, I don't even own a computer these days, i just do everything on my phone. Hopefully just a link will be ok. https://flic.kr/p/RmMG6n

This shows the spider, helical pins, the back of the drive side arm with the glue on it and the fixing bolt.

In hindsight it makes sense the bolt would be imperial what with them being relatively old and American.
 
Re. Those pins. Never seen anything like that. I would suggest tapping the holes to fit nearest size allen head bolts.
 

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