calling the cannondale crank experts! srm vs. frame

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simon
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by simon

hi all
i have a cannondale srm crank(powermeter 6 on hollowgram crank, srm specific axle and left bearing cover)that doesn't clear the bb area of my new frame(felt f series, got beefed up compared to pre-2014 frames)
the srm unit and chainring bolts need 2-3 mm more room, they hit the chainstay before the crank sits tight on the axle.
what ways are there to move the thing outwards a bit?i know i sacrifice q-factor but could live with a few mm as i have sram cranks on most other bikes, mtb pedals etc. so i don't have that ONE setting on all of my bikes.
many thanks for your help!

by Weenie


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goodboyr
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by goodboyr

I believe c'dale has a special bb insert that adds that space. Check at cannondale experts.com
http://www.cannondaleexperts.com/Cannondale-Hollowgram-BB30-Road-Bottom-Bracket-for-SRM--QC850_p_217.html

grover
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by grover

He's already got those parts installed 'goodboyr'

I've encountered the same problem before fitting to a lugged carbon Time. In that case it was one part of a fat lug. The plastic cover is quite thick so we shaved it down. The owner of that bike had given it a hard life and it was out of warranty so he took a file to the carbon lug. He figured it was extra thick in that spot anyway :shock:

I haven't done this and don't know if it'll work but...the SiSl2 spindle is 109mm. Yours would be 104mm.
http://www.cannondaleexperts.com/Cannon ... _2016.html
You could install that as it would push both arms out 2.5mm.

Note that it doesn't have a lip on the non-drive side so you'd have to use spacers between non drive side crankarm and bearing shield to stop lateral play. The nice thing about this is you have infinitely adjustable chainline so in theory you could install some of those spacers on the driveside to get more clearance between spider and frame. Of course that means you're asymmetric by a couple of mm but some people are ok with that.

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simon
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by simon

thanks!!
looking to get an sisl2 axle to try it out. what's the difference(except weight)between the "old" hollowgram arms with sisl2 axle and the complete sisl2 setup?
in other words, could i solve the problem by mounting my srm to a complete sisl2 crank? i know it's way more expensive though...

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ms6073
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by ms6073

The SISL2 crank arms are a tad more asymmetric but replacing the 104mm spindle with the 109mm road spindle should solve the problem. In addition to the 5mm extra length, the new spindle is smooth end to end thus offering more lateral adjustment.
- Michael
"People should stop expecting normal from me... seriously, we all know it's never going to happen"

ProEvoSLTeamHighMod
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by ProEvoSLTeamHighMod

As stated above, try that 109mm spindle. If the SiSl2 arms are asymmetric, this is news to me, as they are designed for use on both BB30 and BB30-A frames which have a non-drive offset.. if the arms were asymmetric they would create an odd (although minimally so) q-factor on one or the other configuration...

Also be aware that spacing out to accommodate the frame's being not really to spec will move the chainline out.. hopefully your shifting doens't suffer.

jooo
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by jooo

Doesn't BB30A just remove the need for a NDS spacer? Not really asymmetric other than that :noidea:

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simon
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by simon

ok so i've found and ordered that sisl2 spindle. hope that works out somehow. i'll let everyone know!

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ms6073
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by ms6073

I had similar issues when I tried to mount a Hollowgram SRM on a Ridley X-Night with PF30 bottom bracket shell and until the SISL2 came out, I followed the lead of another forum member and had the bearing ridge on 104 mm spindles machined-off by a local machine shop. That was a workaround but the SISL2 removes the 'ledge' that held the non-drive side bearing and also adds 5 mm to the length allowing for much better tuning of chainline with spacers as well as moving the wave spring washer to the non-drive side to help resolve clearance issues.

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- Michael
"People should stop expecting normal from me... seriously, we all know it's never going to happen"

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Calnago
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by Calnago

I'm finding this thread kind of interesting and timely (for me). A friend with a 2012 Supersix Evo was having all kinds of issues with his PF30 BB creaking. I basically didn't want anything to do with it but when every shop he tried just seem to slap a bunch of grease in there (which didn't fix anything, just masked the problem), I took it on as a challenge. Well, I got that resolved but in the process couldn't really dial in his DA9000 front shifting. He runs a Hollowgram Sl crank. Initially I just advised he go to a praxis conversion BB and run a Shimano crank, but he got a quark PM for his birthday which was Hollowgram specific (30mm spindle diameter). So that sort of killed that idea and I installed the Quark. But same issue, it seems that the chainline is just a little too inboard for the DA9000 to be set up perfectly so that all the stops work (outer, lower, and two trim positions). Well, I managed to find a spindle for the SRM PM that I had sent to me and I'm hoping the added mm or two on the drive side will be all I need to dial it in. It is still a 104mm spindle but the shoulder has been reduced, albeit not completely removed as on the newer sisl II spindle. I kind of like the idea of the 109mm spindle except it would seem to be a little bit of a pain in the ass to dial in initially trying to figure out how many spacers on each side is optimal for both clearance issues and shifting performance. Pretty much trial and error the first time but I suppose once you've got it figured out then you're good. I'll let you know if just this little extra helps dial in the shifting. Bike is at a training camp down south through Sunday. So next week I should get another crack at it.
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simon
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by simon

keep in mind that the srm specific spindle works together with a special bearing cover that's recessed.spindle and cover move the whole thing 2 mm to the right iirc,srm spindle with normal bearing cover just 1 mm. never found this cover for sale seperately,only in a set with axle,bearings etc.

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Calnago
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by Calnago

Yeah, got the bearing covers with the spindle. Won't be using them. I've got a Chris King PF30 BB in there and it's probably the best thing that's happened to that bike for a while. No bearing covers over the Chris King stuff. They are sealed pretty well.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

Svetty
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by Svetty

viewtopic.php?f=3&t=114357

V familiar with this. Best solution is to get 109mm spindle and fine - tune the chain line by varying the numbers of spacers on both sides.

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simon
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by simon

so far it works...
i have now 2 alloy spacers(included in sram bb30 bearings),1 plastic spacer on each side,the regular sram bearing covers and the wavy washer on the left.that way there's a tiny gap and the system shouldn't move around.it's quite symmetric,nearly same distance left and right between chainstay and crankarm.
off course,the chainline looks a bit screwed for a racer who abuses the drivetrain regularly with big ring and the biggest sprockets,but i'll try it out over the next days in real life.
everything runs without issues on the workstand.
wanted to thank you all again,i save quite some cash if i come around ordering a new srm...

by Weenie


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