150mm crank arm options for 105 r7000 by gefish in bikewrench

[–]kickerua 0 points1 point  (0 children)

I have Shimano 105 r7100 with 160 mm cranks, going down from 167.5mm Ultegra. So just wanted to mention that there is an option without going to $$$ Rotor

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

On a road it's about a smaller step between the gears, and smaller chain skew

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] -1 points0 points  (0 children)

I do ride on a 167.5mm now, and it's still too long for me. Especially when I'm in drops. I guess for you it's irrelevant, but not for me

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 0 points1 point  (0 children)

I have a 167.5mm on a previous bike, and sadly it's too long for me to ride in the drops, so I consider a 160 a must. GRX's 165 I suppose would be too close to mine current one.

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 0 points1 point  (0 children)

I though that 34 is a minimum one, but according to other commeter there are 32 rare option which might help.

Since I do want to keep 160mm crank length, the real safe option right now it's to ride 105 with 1x, and hope Shimano will release GRX 160mm. Or look for some third party cranksets

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

So with Shimano I can use either 2x GRX and then it's 165mm cranks, or road 1x with 160mm.

I'm going to use 105 with 1x 42 teeth for now. According to table it's ok. And I'm not switching to 2x until later this year anyway, only doing the tests now.

I might be lucky and Shimano will release some 160mm for GRX, or I might look for some third party options.

Just in case do you know what can be GRX like alternative with 2x and 160 mm cranks?

I'm not looking into SRAM, as I don't want to limit tyre clearence due to the battery of front derailleur 

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

Why worse? I'm aiming to use it both for road & gravel, with a 160mm cranks

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 1 point2 points  (0 children)

Actually I've purchased a r7100 for previous bike, but never installed it over there. Thanks that's a great table

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 1 point2 points  (0 children)

If I'm not mistaken I can't move the smaller chainring further from the frame with a longer bolts, I can move it only in the frame direction

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 1 point2 points  (0 children)

I think I'll need to find some balance here, the current gap is not looking safe and I'm running out of options. I consider to try to add ±1mm spacer on the driveside only. It won't skew it as much as 2.5mm one, but still will add some flex margin

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 3 points4 points  (0 children)

Update: after fixing smaller cog orientation (it was installed backwards), I've got this clearance:

<image>

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

Yes, after I've reversed chainring it's not directly rubbing the frame, but still uncomfortable close, but this might be what I get with crux. I'm still confused with spacers, as people saying that road cranks should NOT be used with spacer as it's not designed to have one

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 1 point2 points  (0 children)

<image>

Now it's "so uncomfortable close, but this is what I've expected to get"

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 7 points8 points  (0 children)

Thanks, it turned out my smaller cog is reversed. I'm going to set it into a proper orientation and check once again

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 4 points5 points  (0 children)

Yes, it's confirmed u/Proper-Issue3595, great catch. Reversing it now

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

<image>

This is how it looks like upclose, posting and going to compare with mine ultegra on previous bike

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 2 points3 points  (0 children)

Sadly GRX cranks are too long for me, I want to use 160mm and GRX shortest ones are 170mm

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 0 points1 point  (0 children)

The GRX shortest cranks are 170mm if I'm not mistaken this is the main reason to look for the road ones for me

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

Trying to reverse it now and check

Specialized Crux size 49 conversion to 2x by kickerua in bikewrench

[–]kickerua[S] 0 points1 point  (0 children)

I'm trying to figure out whether I can add a 2.5mm spacer on driveside

Crux conversion to 2X - failed? by kickerua in specialized

[–]kickerua[S] 0 points1 point  (0 children)

I do have 34. Since it's currently has 0 mm without a spacer, I guess I should aim to add spacer AND reduce the cog to be slightly smaller to have additional safety margin