is it true no sub-compact crank for bb90?

[eddief]

I have considered getting a pre-2020 Trek Domane with PF BB90 and to the best of my googling fingertips I can't find a 48/32 or 46/30 crank that will fit it...except for GRX which I guess would be ok. But with Di2 that would also mean adding a new FD. I hate the aesthetics of the 2020 models and I know the alleged issues with BB90.

I even considered going Etap 11 but not sure Etap FD can handle GRX chainline.

others besides GRX?

[Tony]

I have considered getting a pre-2020 Trek Domane with PF BB90 and to the best of my googling fingertips I can't find a 48/32 or 46/30 crank that will fit it...except for GRX which I guess would be ok. But with Di2 that would also mean adding a new FD. I hate the aesthetics of the 2020 models and I know the alleged issues with BB90.

I even considered going Etap 11 but not sure Etap FD can handle GRX chainline.

others besides GRX?

Why not use sub compact rings like Absolute Black on your compact crank?

[thermalattorney]

I even considered going Etap 11 but not sure Etap FD can handle GRX chainline.

If the Domane used clamp-on FDs, you could get a "Wide Spacing" clamp that shifts the chainline 2.5mm outboard. Since it has a braze-on mount, I don't think it's worth the risk.

[jtbadge]

Looks like they're out of stock, but you can mount these 46/30t rings to standard 5-bolt 110bcd cranks:

https://www.ebay.com/itm/bikinGreen-CNC-Road-Chainring-46-30T-BCD-110mm-5-Bolts-9-11-Sp-Cyclocross-Tour-/123706511747

[thirdgenbird]

Chorus has a subcompact and trek sells an appropriate bearing kit for ultra-torque. If my searching is correct, the chainline is only +1mm. Grx is +2.5mm


Chorus cranks with e-tap would get a high five from me.

[eddief]

the utube about ultratorque install looks ominous with the "gluing in" of the bearings. but maybe that is on older Treks?

Chorus has a subcompact and trek sells an appropriate bearing kit for ultra-torque. If my searching is correct, the chainline is only +1mm. Grx is +2.5mm


Chorus cranks with e-tap would get a high five from me.

[jtbadge]

Also there are these cranks from IRD that use a 110bcd big ring, 74mm small ring, and 24mm axle (i.e. Hollowtech-compatible)

https://www.interlocracing.com/shop/product/ird-crankarms-bb-lobo-2520?search=lobo

[Mark McM]

As above, there are plenty of options for sub-compact cranks that fit BB90.

Two you might want to look into are the Sugino OX series and IRD Lobo compact cranks. Both feature 24mm spindles (which is what BB90 is designed for) and 110mm/74mm BCDs, and are available in either silver or black (alloy). The Sugino OX cranks feature a road width chainline and narrow Q factor, while the IRD Lobo has a wider chainline (and Q factor) for bikes with fatter tires.

If you want carbon cranks, look into the previous discussions on SRAM Force 22 road cranks, which have 24mm/22mm spindles and interchangeable spiders. Spiders are are available with a variety of BCDs, including 130mm, 110mm, 120mm/80mm, 110mm/74mm, and 96mm/64mm. For a wider chainline, you can look at the SRAM XX1 Q156, which takes the same spiders as the Force 22.

[eddief]

oops

[muz]

I hate the aesthetics of the 2020 models and I know the alleged issues with BB90.


I don't know that i could pick out a 2020 from a 2019 from 6 feet away. But the 2020 has some nice upgrades like threaded BB and room for 40mm tires. It would take a huge discount for me to pick '19 over '20.

[eddief]

the only improve i'd care about is t47. and might eventually come around on looks.

i think it's the seatpost integration or the lack thereof that strike me as oogly. first it's a topper, then it's an inner, what next? proportions look outa whack.

https://cyclingtips.com/2019/07/2020-trek-domane-first-ride-review/

I don't know that i could pick out a 2020 from a 2019 from 6 feet away. But the 2020 has some nice upgrades like threaded BB and room for 40mm tires. It would take a huge discount for me to pick '19 over '20.

[eddief]

idea is easiest route to these subcompact options with bb90 bottom bracket.

As above, there are plenty of options for sub-compact cranks that fit BB90.

Two you might want to look into are the Sugino OX series and IRD Lobo compact cranks. Both feature 24mm spindles (which is what BB90 is designed for) and 110mm/74mm BCDs, and are available in either silver or black (alloy). The Sugino OX cranks feature a road width chainline and narrow Q factor, while the IRD Lobo has a wider chainline (and Q factor) for bikes with fatter tires.

If you want carbon cranks, look into the previous discussions on SRAM Force 22 road cranks, which have 24mm/22mm spindles and interchangeable spiders. Spiders are are available with a variety of BCDs, including 130mm, 110mm, 120mm/80mm, 110mm/74mm, and 96mm/64mm. For a wider chainline, you can look at the SRAM XX1 Q156, which takes the same spiders as the Force 22.

[robt57]

Looks like they're out of stock, but you can mount these 46/30t rings to standard 5-bolt 110bcd cranks:

https://www.ebay.com/itm/bikinGreen-CNC-Road-Chainring-46-30T-BCD-110mm-5-Bolts-9-11-Sp-Cyclocross-Tour-/123706511747

I got these, and had to wavy washer the drive side as it tightened the chain line with them on. Wonder if the Absolute Blacks are like that too.