Pretty experianced home mechanic preparing to flat bar my gravel bike for a giggle (and some fit improvements)
I am currently running shimano 11spd GRX and have ordered some mtb brake levers (deore 6100 which i know arnt very officially compatible but everyone ive spoken to says are fine)
What am i going to need in terms of olives and hose? will it come with the brake levers or will i need to order something else?
cheers
Photo of the topstone in question!
Running uder the assuption that you are running M6100 levers with GRX calipers, the SM-BH90-SS kit that may come with the levers should do it. Relative to both the caliper- and lever-specific connection, the Deore and GRX calipers are identical, requiring the standard flare nut/olive/11.2 mm silver barb combo. The lever connection is the differentiator here: this requires the SS kit, versus the JK-SSR kit called for by the GRX manual. Order the -SS kit and you should be good to go. Good luck! 
I converted my Lynskey GR300 to flat bar and the existing hoses were plenty long enough to use. I just shortened them to length.
I have no idea if the levers come with connecting hardware or not (they should at least come with a nut). but standard bh-90 barb and olive should work (assuming that’s the hose you have)
what are you using for shifters? I have had a set of the road-derailleur flat bar shifters (SL-RS700) sitting around for a while, just haven’t found the time to make the swap yet.
Next problem…. Shifter has turned up and it’s I- spec 2 
the band on one is out of stock everywhere in the uk.
Will i-spec 2 that looks like this picture be workable with I spec ev deore brake lever?
Shimano won’t say officially that I-Spec A/B/2 are inter compatible with I-Spec EV, but I’ve had luck getting them to mount to EV clamps by using a spare brake rotor bolt, rather than the longer bolt that I-Spec 2 components use.
thanks , yeah what wierds me out is that this is the ‘tuck it under the brake lever clamp’ style of mount rather than the bolt in version that the mtb’s have. 
I will have everything turn up tomorrow and can just test it out! 
