2x MTB crankset compatible with press fit GXP-A1 PFGXP ROAD 86.5/WA91.5

[EMGX]

Against better judgement I'm sort of considering a carbon non-E 1x gravel bike that comes with 40t chainring (minimum 38t compatible) and 11-42t 11 speed cassette SRAM Apex1 derailleur. That setup won't provide even close to the lowest gear ratio that I require. I could add a front derailleur and a 2x crankset but it appears that only MTB specific would provide the low gearing I need, something like 38/26. AI tells me that MTB crankset wouldn't be compatible with GXP-A1 PFGXP ROAD 86.5/WA91.5 press fit bottom bracket but "you can mount an MTB GPX crankset into an 86.5mm road bottom bracket by using a GXP-specific spindle spacer kit." I don't want to get in over my head and end up with a bike that I can't ride up the hills where I live. If anyone with expertise can offer clarity/solution please post up.

I'd like something like this crankset https://www.sram.com/en/service/models/fc-x5-a1

 

[Brendon@OEB]

MTB bottom bracket shells are usually wider, 73mm compared to 68mm from the road/gravel/touring side. The "kit" is simply a spacer that slides over the crank spindle so the non drive crank can properly tension and attach to the spindle.

What about an MTB cassette? Since you're using SRAM you can use their wide range MTB cassettes out back.

 

[EMGX]

Apex 1 is rated 42t max (some report useable with 46t) and the crankset is rated 38 minimum which gives ~25 gear inches. I have my BH/Yamaha set up with 44/32 and 11-40 with Shimano 105 5800 and wolf tooth roadlink giving 22+gear inches which is barely low enough for long steep inclines unless I use the higher assist which I like to avoid. Another bike I have with 3x10 drivetrain has low of 16 gear inches which I do make use of - pretty much necessary for me for a non-assist bike. I'd rather go slow riding than getting off to walk, although I do that too.

 

[stompandgo]

Change the front ring to a 38, replace the rear derailleur with an SX Eagle and either a 10-50 or 11-50 cassette, and work on your leg strength. If you need MTB gearing on a gravel bike, you should get an MTB.

 

[EMGX]

38/50 with 700c wheels won't cut it for a non-assist bike for me where I live/ride. Two current ebikes with lows of 30/40 and 32/40 700c. I don't have use for a mountain bike anymore. I was looking more for a light bike (the one I was considering is 21#) with sub 20 gear inch low. I used to ride the hills around here grinding out of saddle but those days are gone limited more by joints than muscle as I'm fairly fit and strong for my age. For days that I'd want assist I could throw on a Keyde thru axle rear hub motor in literally minutes and still have a sub 30# bike with better performance than Mahle X35 per reports from @peterecosse. I already have a regular axle Keyde on an old mountain bike (16-18 gear inches low depending on cassette), it performs well IMO, was hoping for something that would be lighter with and without a motor but I'm not going to bodge up a new bike.