2010 Cotic Soul + Square Taper Middleburns - 113mm or 118mm HELP!

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2010 Cotic Soul + Square Taper Middleburns - 113mm or 118mm HELP!

17 posts & 9 voices | Started 1 year ago by letmetalktomark | Latest reply from Denis99

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letmetalktomark - Member

There seems to be a number of people who have had clearance issues using a 113mm axle length BB with a 2010 frame and have increased the axle length to 118mm.

Where exactly is there a clearance problem? Pics? Speaking with Cliffe @ Royce this morning about one of their Ti bottom brackets he recommend no more than 113mm with an RS7 and a 135mm rear drop out.

I have a frame on its way to me with 113mm & 118mm shimano BB's to test but ahead of its arrival I wanted to get the lowdown from folk on here first.

CY; if you read this might you be able to help?

I plan on running a 1x9 set up with a 32t ring but also want the flexibility of a dual ring depending on how I get on. (thought it worth mentioning in case it makes a difference)

Many thanks in advance,

Mark

Posted 1 year ago #
Denis99 - Member

I've got a 2010 Soul and Middleburn RS7's.

Bought a UN53 113mm x 73mm, as Middleburn say this is the correct width b/b axle.

Fitted it and the righthand (driveside) taper pulled up the taper and just catches the internal splines of the b/b. This fouling of the splines undoes the right hand bottom bracket cup.

Fitted a 118mm and all is fine.

The 113mm will foul the drive side crank spider.

I've got a brand new 113mm in the spares box now, because it won't fit.

~~
Its the spider which fouls the internal cutouts on the b/b (where the tool fits), so it won't make any difference whether you run one/ two or three rings. I've measured the chainline and its 48mm from centre of seat tube to middle ring.

Posted 1 year ago #
orange - Member

i've used 115 and 118, but it was on a mk1 soul

Posted 1 year ago #
mudsux - Member

but won't increasing the axle length by 5mm give you really w@nk shifting?

Posted 1 year ago #
letmetalktomark - Member

mudsux - Member

but won't increasing the axle length by 5mm give you really w@nk shifting?

That is what I am concerned about

@denis99 - The problem you describe seems that would happen on any frame as its a BB/crank clearance issue or have I missed something?

I ran a 113mm axle and RS7s on another build and there were no clearance issues

I don't know

Posted 1 year ago #
nuke - Member

It's only 2.5mm each side so it's not going to make a massive difference. Ran 118mm on my Inbred and on my PA with no shifting problems...can't see the Soul would be hugely different

Posted 1 year ago #
soulwood - Member

I have a Mk 2 (slight modification to the frame in its second year) Soul, and I found width issues when running 2.3" tyres rubbing on the front mech when in granny ring. I used to run an extra BB spacer to clear it on an external BB, but with a square taper can you still do that? I eventually resolved it by using an e-type front mech, despite it not being bolted to the frame it has been fine and I don't need any spacers.
Also I don't think an extra 5 mm will affect your shifting, it didn't for me, but then I don't use rapidfire shifters... old school thumbshifter for front mech duties for trim as I think RF is w**k for that.

Posted 1 year ago #
Denis99 - Member

I was confused as well by the width of the axle, took the bike to Skyline Cycles, where one of the mechanics has an early Soul frame.

He runs a 113mm bb width, but could clearly see the problem.

118mm does have a "perfect" chain line, but its very close. Could possibly try a 115mm, but for the moment the 118 will more than do.

Its the lockring on the spider that fouls the bb shell.

Posted 1 year ago #
Conespanner - Member

I've got a very old Cotic (frame no. 5) and also use an Middleburn RS7. I've been using a 113mm UN53 BB, but my cotic has a 68mm shell as did all the very early ones. Surely a 73mm shell would need a 118mm axle? It's only 2.5mm difference per side and that can't have that much effect on chainline?

Posted 1 year ago #
Denis99 - Member

As I said, I measured the chain line with my calibrated vernier gauge.

Centre of seat tube to middle ring 48mm,seems spot on to me.

Visually with the chain in the middle ring and positioned on the centre of the cassette, it looks very marginally out.

Posted 1 year ago #
letmetalktomark - Member

Cheers for the response and clarifications.

I have both 113mm & 118mm so will get some pics up whilst experimenting.

@Denis99 Do you have a picture of your complete bike?

Posted 1 year ago #
Denis99 - Member

Yes, I've got images - search my posts if you need to look now, can't link from work (don't finish until later).

Posted 1 year ago #
younggeoff - Member

OOh, my soul must be an early one as it has a 68mm bottom bracket, were there any differences with the right hand chainstay.

Posted 1 year ago #
cy - Member

I don't know the answer here, but taking advice from people with older frames won't help because I've changed the chainstay shaping over the years. The current chainstays are optimised for the wider 50mm chainline of HTII type set ups and I used it as an opportunity to get rid of all the crimps in the chainstays so the frames will last longer. From what I've heard on this subject, the guy up there hit the nail on the head, I think the issue is not with the frame but with Middleburn cranks as they don't seem to work on the recommended BB length on the 73mm shell.

Posted 1 year ago #
letmetalktomark - Member

Cheers Cy.

In case it is of use to you when I fit the cranks I will take pics of any clearance issues and pop them over to the Cotic inbox.

Hopefully 118mm will be okay & a 48mm chainline as measured by dennis99 shouldn't prove problematic.

Posted 1 year ago #
Denis99 - Member

I'll take some photos this morning and post up the link.

Posted 1 year ago #
Denis99 - Member

Just uploaded images to my pbase photo site, click the link to see quite a few images.

There is approx 1 to 2 mm clearance between the spider lockring and the right hand bb cup. So fitting a 115mm bb would be tight, but it could work (just).

UN53 73mm x 118mm square taper bb om Middleburn RS7 cranks.

Re measured chainline at 48mm.

Chainline photos taken with middle chain ring (32T) to middle of cassette.

Hope this helps, looks fine to me.

Unfortunately I can't ride any real distance on the bike at the moment due to a leg injury (that would have to be another post though.....)

http://www.pbase.com/denis99/cotic_soul_2010&page=2

Posted 1 year ago #

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