compatibility front derailleur / crankset ( convert 1x to 2x )
 

I want to convert my Ibis hakka mx 1x grx to 2x grx

https://www.ibiscycles.com/bikes/hakka-mx

Cranks Praxis Zayante Carbon S 30mm spindle, 40t Alloy Ring

Bottom Bracket Praxis M30 - T47
Rear Derailleur Shimano GRX RX812 Shadow Plus
Shift Levers Shimano GRX R810
Cassette Shimano XT 11-46



I purchased the left Shimano GRX ST-RX810 Hydraulic Brake Lever. I have 11-40T cassette also. I don't think the 11-46 will work with 2x setup.

I can purchase 2x chainring for the Praxis Zayant carbon crankset that's on my bike. The praxis website says it's

not compatible with 2x grx front derailleur.
https://praxiscycles.com/product/zayante-carbon/
CHAINLINE 2X = 44.5mm ROAD | NOT compatible with Shimano GRX front derailleurs

1X = 45.5mm ROAD


Can I just buy this?
Shimano Dura-Ace Front Derailleur Braze-On Adaptor

https://www.biketiresdirect.com/prod...waAnFaEALw_wcB

Shimano GRX FD-RX810 11-Speed Front Derailleur

https://www.biketiresdirect.com/prod...ont-derailleur

or do I need to buy this to work the praxis crankset ?
Shimano Ultegra FD-R8000-F Braze On Front Derailleur

https://www.biketiresdirect.com/prod...ont-derailleur

or should I just buy

Shimano GRX 810 2x11 Crankset and buy a new bottom bracket for the T47 so I will have matching grx front and rear Derailleur

https://www.rei.com/product/161259/s...B&gclsrc=aw.ds


I have seen non shimano cranksets work with grx Front Derailleur.
My 2021 Giant Revolt comes with Crankset Praxis Albe 2D, 32/48
https://www.giant-bicycles.com/us/revolt-advanced-2

yet Praxis says that crankset
https://praxiscycles.com/product/alba/
CHAINLINE 2X = 44.5mm ROAD | NOT compatible with Shimano GRX front derailleurs


So, I don't know what to believe any more.

They really don't make this easy, do they. Apparently the chainline on GRX from derailleurs is 2.5 mm outward.
According the Lennard Zinn you could use an Ultegra FD, which is a lot less expensive than getting a different crank. https://www.velonews.com/gear/techni...ount-calipers/
There are several other gravel crank options if you want to go that route, including White Industries G30 and FSA Energy or SL-K.

I went from a 1x sram force with the same Praxis carbon cranks to a 2x GRX system on my 2019 Diverge. My first attempt included a 2x praxis levatime 2 chainring/spider swap in. The GRX FD handled the 2.5mm difference just fine. I doubt it would be a problem as i have seen a few reports of road FDs being used with GRX cranks without issue.

The problem I had was the chainring bolts to chainstay clearance. There was about a 2mm gap which I felt was enough, but after 1 ride I could see the witness marks from the chainring bolts rubbing on the chainstay. My ultimate solution was to buy the GRX 810 2x crankset. The 2.5mm outboard chainline worked perfectly and I no longer have any contact in that area.

Edited to add: Per Praxis the M30 bottom bracket cannot be shimmed over. I confirmed this when I tried and the BB bearings bound up.

I will say the Praxis chainring shifting was much smoother than the GRX. Even smoother than my roadie bike with full DA.

My Praxis 1x front and shimano 812 rear derailleur with shimano cassette is constantly dropping the chain. Even on a smooth road going up hill like today. I know a lady with an Ibis MX and she bought the sram package instead of the GRX like me and she has the same problem. On my mnt bike there's a little plastic guide by the front chain ring. I wonder if that helps because my Ibis does not have it.

yesterdays gravel ride dropped 3 times ( factory wheels / tires )
https://www.strava.com/activities/7245971892

todays road ride, dropped twice while going up hill ( carbon wheels, smaller cassette 40T vs factory 46T maybe that's why it fell off the back cassette )
https://www.strava.com/activities/7256112697


So it looks like as long as I have clearance for the chainring & bolts etc then GRX front derailleur should work with my praxis chainring.

Thanks for your input that has helpful.

https://praxiscycles.com/product/zayante-carbon/
https://praxiscycles.com/product/levatime-ii-x-kit/
https://www.biketiresdirect.com/prod...waAnFaEALw_wcB


https://cimg1.ibsrv.net/gimg/bikefor...6529ee25b.jpeg


It all bolted together just fine. A short little ride it was fine. I have a bigger ride this weekend to see if anything crops up.

update praxis and GRX FD
 

Hi All,

Any update on the Praxis crank with the GRX FD?
I'm planning on something similar and was wondering if it all worked well in the end..

My '22 Checkpoint came with the Praxis 2x and a GRX front derailleur, even though Praxis says it doesn't work. Well, it doesn't work well. I could get it set so it would shift ok from the big/small chainrings, but much cross-chaining at all and the der was scraping on the chain. If I was on the big chainring I couldn't be on the 30 or 34 on the cassette or the chain would drop. Or if I was on the 11 or 13 the front der was dragging on the chain. I finally gave up, pulled off the front der and changed to a 1x setup. YMMV
https://cimg7.ibsrv.net/gimg/bikefor...5b0781082e.jpg

Sounds like I need to try and see if I can make it work.. I'll post, once I have some info to share.

My Ibis in post # 5 has been working great with 2x praxis and grx front derailleur. I have over 2000 miles since I converted from 1x.

my bike requires this mount which might amount more leeway on you mount the derailleur vs a braze on mount.


https://cimg0.ibsrv.net/gimg/bikefor...3055dd2b76.jpg