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E.13 DRS on a Nomad??

erikkellison

Monkey
Jan 28, 2004
918
0
Denver, CO
Okay, so I know a million people must be running these, and I must be doing something wrong. Maybe y'all can tell me what it is.
I have an ISCG 05 DRS and a 73mm BB Nomad. I am having serious issues.
I do have the 5mm plastic spindle spacer on the driveside arm. I have 2 x 2.5mm BB spacers installed on the driveside, outside of the 2.5mm wide ISCG05-BB mount adapter. The BB adapter is installed concave side inboard so as to bring the DRS as close to the bike as possible. With this setup, I finally got everything to line up right (with only one wear plate installed). But now that it's all lined up, the thread purchase for the driveside BB is dismal (5mm less than it was, maybe not even 10mm now!). More importantly, there is now so much junk spacing it all out that I can't even get the preload nut to fit into the threads on the non-driveside through the crankarm. So clearly, I am not allowed to run those extra 5mm of spacers. But if I take 5mm of spacers off the BB on the driveside, the inner chainring bolts will contact the guide - actually, as it is, there's about 1mm of clearance with the 5mm of spacers installed, and if I remove them, there will be a 4mm gap where the crankset isn't inserted into the BB enough (4-5mm of spindle exposed between the plastic spacer and the BB cup). Adding another 5mm spindle spacer would only do the same thing that those 2 2.5mm BB spacers are doing - I would still be too short on the non-driveside to get thread purchase.
So I've concluded that I need a BB mount DRS. Here's why:
After all the fancy spacing that I've done, the end result is that the DRS backplate is exactly where I want it in relation to the inner chainring bolts (about 1mm away). Now, if this giant hole for ISCG05 was a BB mount hole instead, I could get rid of the 2 2.5mm spacers, move everything inboard by 5mm, and be set to go. The ISCG 05 to BB adapter that I have does not make this possible as it's made to space things outboard, not inboard. It doesn't work if you mount it on the other side of the backplate.
So I guess my question is: are all you Nomad riders with DRS' running the BB mount backplate? Or is there something I'm doing wrong?
Thanks in advance.
 

erikkellison

Monkey
Jan 28, 2004
918
0
Denver, CO
Of what? I already took it apart....
If a description helps, visualize this:
In order, from left to right, facing forward:
preloader nut
non-drive side crankarm
spindle
left BB cup
73mm shell
ISCG'05-BB adapter, concave inward
2.5mm spacer
2.5mm spacer
drive side BB cup
5mm plastic spindle spacer
drive side crankarm

To expand on the adapter:
It is concave inward, and the DRS is bolted to the flat (out) side
There is one wear plate installed (out of an optional 4)
The inner chainring bolts are about 1mm from the DRS ISCG'05 mounting bolts
This means that the drive side crankarm can't be any closer to the DRS
The fact that the adapter is spaced as far inward as it can get, and that's still 5mm too far outboard has made me determine that I need a BB mount backplate.
I already had an order I needed to place for a part at Pricepoint.com, so I actually bought a Blackspire Stinger instead. If I can't get that to work, I'll special order the proper BB mount backplate for the DRS (Pricepoint doesn't carry the backplate that I need).
 

BillWC

Chimp
Jan 25, 2008
6
0
What kind of cranks are you running? Most likely your cranks are not compatible, I've run into this problem many times, especially on Raceface cranks.
 

erikkellison

Monkey
Jan 28, 2004
918
0
Denver, CO
I'm running Shimano XT M760 cranks.
I'm pretty sure I solved the problem though, err, not solved it, but have concretely figured out that I need the BB mount backplate. This is because there is no way that ANY adapter can get the ISCG 05 backplate inboard enough. It's just not possible without some weird custom adapter. It MIGHT be possible if I mounted the adapter on the outside of the guide, but then the adapter hits the chainring bolts. Basically, the bottom line is, if you have a 73mm BB and want to run a DRS, get the right backplate for your mounts. If you have tabs, get the tabbed version. If you don't have tabs, get the BB mount version. Adapters don't work in this instance. They did work when I ran a single ring up front with an LG1, but that's because the 1 ring was outboard more, and that was fine. The 2 ring setup is much more specific in its needs. Anyway, Blackspire Stinger here I come!
 

PhilipW

Monkey
Mar 13, 2007
313
0
Leominster, MA
Hey Erik,
You're right...you need the Bottom Bracket mount version of the DRS backplate. The ISCG adapter plates are designed for our single ring systems, and it spaces out the DRS too far as you've experienced.
Shoot me an e-mail at philipw@e13components.com and I'll get your backplate switched out for the correct one ;)

Cheers!
 

erikkellison

Monkey
Jan 28, 2004
918
0
Denver, CO
Okay, so Phil from E.13 contacts me about this issue, and basically is swapping me my ISCG '05 plate for the BB mount plate that I need at no charge! Now if that's not excellent customer service, I don't know what is. You can bet that I'll be running the DRS over the Stinger for sure. Thanks Phil!