• Just wanted to summarise on some tech points discussed so far and share my experience on them.

    OSMAND is a fantastic app. So far in my experience nothing has come close to level of detail and flexibility for emergency measuring/routing when out and about in the wild. Pay the few euros to download the maps, and to get the elevation shading and contour lines. Avoid the monthly subscription they try to push unless that is really your thing to get updates every day. Make sure you have enough memory on the phone, or consider saving the map data on a micro SD card at install. Get familiar with the Measure Distance and Snap to Road feature. Use the save as GPX file feature and then go to My Places to recall and study them. OSMAND shows detailed elevation both when routing and saving GPX tracks via the measure distance feature. A life saver when making decisions on the fly.

    The GP5000 measures from the total external width unlike the previous 4000 that measured from the internal tube width. It means a GP5000 at 32mm is the same as a GP4000 at 28mm. In my use case, the 5000 measures 32 on a 20mm internal rim, the 4000 measured 31.

    The shimano road road going rear mech in the long cage GS variants that are spec'd for a max of 34 teeth, are happy enough up to 40. The Wolftooth roadlink is not necessary with a GS nor is it the ideal solution. The roadlink moves the mech pulley away from the cassette compromising shifting and wear. If an 11-42 rear cassette is desired, then an XT RD-M8000-SGS and a Wolftooth Tanpan is necessary. You can put the Tanpan in line near the bars instead of at the rear.

    The Absolute Black sub compact 30/46 and 32/46 front rings mount 2.5mm inboard towards the frame. It means your chainline changes by -2.5. So a non disc brake based road crank (practically all of them) with a chainline of 43.5 will be 41mm. If you have a really short chainstay this can be problematic. The chain angle can make the drivetrain unhappy. Chainstays of 435 seem ok with it, 450 has no issue with it. On my 410 and 412 bikes it didn't like it at all.

    The ovality of the AB rings is actually great. The shifting has been flawless and along with the Rotor Q rings, the same or better than my Shimano experience. However, on one ride, the chain got lodged between the mech hangar and the AB large ring and bent the mech outboard. Took me 30 minutes to get the issue resolved and riding again. But I lost one of the two plastic pieces that are clipped inside the new shimano front mechs. This meant readjusting the shift cable tension and mech limits. I have about 6000 km on oval rings of Rotor and AB, and this was my first issue. I never figured out exactly why it happened. As far as I remember, the adjustment was as per the AB instruction video. Moral of the story is that it is really important to adjust the distance from the large ring to mech hangar exactly how AB recommend, which is different than the usual 1 ish mm between chainring teeth and hangar.

    The AB use proprietary bolts for their rings. Maybe bring an extra set to be safe?

    Wish a technically trouble free ride to all you you!


    Thanks for very informative post!

    I immediately dug out the geometry chart when I read it. My frame is fairly relaxed, but the chainstays are only 425, so it might be in the 'interesting' zone. The rings are in the post: will try them and see.

    I use OSMAnd+. It is a very good.


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