Middleburn RS1 Help

[dc2100k]

Had a little problem with the RS1s I recently took off my old Clockwork. I trien to loosen the 5 small grub screws that hold the spider to the crankarms but 2 have broken down their shaft! The arms are now dissociated from the spider but have two bolt shafts in the threads. Anybody got any idea how I might remove them?

I did a search and somebody mentioned Middleburn have these screws available, I think I need a new set! Also, were I to replace the chainrings (currently well-used Pace items) what type do I need? I am guessing that the compact type mentioned are too small for this.

I was planning to fit them to my 1996 Orange P7, although I may reconsider if (as I have worked out) I need a new bottom bracket as well. The cranks were originally on an old DX/XT B/B as far as I can remember and stuck well out of the B/B shell. The P7 has STXRC numbers on it at the moment which sit very close to the shell, but I cannot get over how weedy the 42 outer ring is compared to the Pace 47T on the Middleburns. Might I be able to use them on the current B/B if I was to forego the inner ring? Can I set the derailleur to stop it dropping down by accident?

I'll post a photo if I get a chance, any advice or experience welcome.

Kind regards,

James.

 

[hamster]

Probably the only way to get them out is electrical machining (also known as Spark eroding)

Essentially a spark attacks it and slowly vapourises it. Takes ages, but I used to use it at work when somebody did exactly what you've described to a piece of aircraft equipment.

It won't be cheap, and can take hours. For a consumer product like a chainset it probably isn't worth it, unless you have a friend somewhere...

You could try you local yellow pages, but don't hold your breath!

 

[garethrl]

semi-hijack alert!

Hi, I can't offer any constructive information on how you might solve your problem, but if you give up on the cranks then I would be interested in the LH crank if it's 175mm! I have a mis-matched pair of RS2s with 175mm drive side crank and 170mm non-drive.

From memory, when I built up the bike I used a 122mm bottom bracket to get the correct chainline and clearance for the RS2s set up as a triple. If you want to run the RS1s as a double you would still need a BB spindle of >117mm and many/most modern BBs have shorter spindles than this. They are still available of course, but the point is that even if you have some old square taper BBs lying around, you would probably need to buy a new one to use with the RS1s.

Hope this helps,
Gareth.

 

[cyclerelic]

rs 1 cranks

i have a blue pair of rs 1 s fist thing to do is to lossen the bolts and copper greese them well and the spider ...i have heard a few tails of bolts snapping and getting stuck inside ,a guy got his stuck like you and had to sell them for £17.00 !! cus he had the small screws stuck inside solid he took the cranks to a mech shop and the guy got them loose ,with you i guess you can get a pro enginer to drill and re tap holes ..i allso read that its best to replace the small bolts with stronger stainless ones tho where you get these from i dont know if you find out give me a shout would love some ...i love these cranks but there seems to be a weekness there ...sorry i can help that much