It all depends on your rim/tyre combination and the resulting actual measured dimensions, i did a experiment mounting panaracer gravelking slick 38 on i29 rims -> WAM 43mm. Very little margins for mud/debree around the chainstays (~2mm) and the front deraileur were (just) touching the tyre.

I'm now running Vittoria N.EXT 34mm on i23 rims, WAM36 this leaves 6mm clearance to the chainstays.

Based on this i'd say if you are modest with the internal width (<=23-24mm) a 38mm tyre will problably be OK but if you want to be on the safe side go for 34-36mm tyres.

38 mm on the R088?! No way. Does not even clear 35mm (iw 21mm) in the front.

Almost done with mine, or are we ever done with a bike build? Anyways, first 100 km done, so just want to give som first impressions.

This thing feels fast (subjectively at least)! It both holds speed easily, and gains it quickly. I am however coming from a bike with different wheels(deeper wheels), and another gearing, as the R088 is built up with 52/36+11/30 vs. my other with 50/34+11/34. The bike feels stiff, but still comfortable. The frame is what I expected it to be, so happy for that.

The bike is a bit soft in the front (think GCN), but right now I am running spacers with the hight equivalent of some skyscrapers in NYC, plastic compression ring, and 40mm expander plug. I am waiting for some shims for the metal c ring, as the one I got was to low, and I also have a 80mm expander plug on my desk. However, I am having some problem with the expander plug "taking", so it just spins and I can screw into eternity, any tips?

The frame itself was mostly fine, with the exception of some base paint showing around the top of headset, a bit annoying as it kills the look of a otherwise great frame. But I will try to get some touch-up paint, and try to fix it. But I really wish Spcycle could get their act together regarding paint. Also the UDH I got with the frame I just had to bin, as it would not let the axle in. Think it was badly machined. But the great thing about UDH: easy fix, just got a new one from my local shop. I had trouble fitting the BB, so I took it to my LBS, so they could tape(is that the word?) the threads, but they did not have to, they just used more force then me and it went in.

Attached is a (bad) picture of the bike, and the upper headset paint.

Anyway, enough from me, I will head out and ride 

Could someone recommend me some good integrated handlebars for this frame? I got a Kocevlo Roval Rapide clone, but lost all confidence in them as they were very flexible and made funny carbon noises just being touched.

Had my eyes on LightCarbon HBR17, but they don't have my size in stock.

Thanks for the feedback regarding spokes, Sander and RLA. Appreciate it. Gives me something (more) to think about. 

Just ordered this crankset. Had to go down to 160mm length due to the wide q-factor of 165mm, but will be interesting to try. Anyway, my main use will be with Ultegra chainrings, but I am going to the alps this summer, and was thinking if I could fit my GRX chainrings for that. Does anybody know of a spider that fits this crank and GRX chainrings(BCD110/80?)? Tried to google a bit, but seemed to only find for Rotor cranks, but I might be missing something.

Also, since I’m riding a small frame, the seat tube bottle cage bolts are too high, which makes it impossible to take a 750ml bottle. Are there any solutions to lower the bottle cage mounts?

Just search ali for "bottle mount adapter".

I tried fitting them on a pair of Roval Rapide CL II. Had to give up, and sent the tires back. GP5000 felt like a walk in the park after.

This post is hilarious reading. 10/10 would watch the movie.