The Nicolai 135x12 bolt-through system
Most Nicolai frames are now compatible with the bolt-through system. For a number of models this has already become the standard or it is available as an option without an upcharge. Bolt through hubs are stiffer than quick release hubs and there are now a lot of capable hubs and wheelsets on the market at fair prices. That’s all common knowledge but we would like to explain why we've decided on the 135x12 mm system in particular. (150x12 for Ion ST)
QR-10 quick release hubs make still have a small advantage in weight so it's still preferable to use them for XC and marathon riding where, normally, loads are not extreme. However, with a QR-10 rear hub the interface mainly relies on friction between the hub and dropout - the quick release lever itself is not able to have any real impact on the stiffness of the rear. That is why, for intense bike use in rough terrain, we recommend the bolt through system.
The Nicolai bolt through system through is designed around the common 135x12 mm standard. Rear hubs of this standard have got an end-to-end hollow axle with an outer diameter of 18 – 20 mm and an inner diameter of 12 mm. When the bolt is attached the hollow hub axle is pressed with positive locking force between the drop outs so that the rear hub, and the bolt itself, become integrated, load-bearing, components of the frame. This makes the whole rear end of the bike perceptibly stiffer.
Compared to other rear axle systems, which use a fine pitch thread, the Nicolai design comes with a regular metric 12 mm thread that allows easy and hassle-free mounting even in sandy or muddy conditions. The only tool required is a 6 mm Allen key. If the axle once should seize after a long period of non-use, or if the 6 mm inner socket should round off, the Nicolai axle can also be released and mounted with a 17 mm ring spanner. Last, but by no means least, the Nicolai bolt through system is fully compatible with the Rock Shox Rear Maxle ® standard.