Chain tunnel I believe it was the german "Fighters Magazin" where I saw pictures of a Turbo-Zed that had the chain running trough the frame. This gives room for a rear tyre that's approx. 240mm wide. This picture gives a good view of the chain-run. A closer look to the tunnels and what seems to be a chain-tensioner with a green roller. Some people aren't really convinced about the ingenuity of the setup I believe. Well... I guess it's too late for second-thoughts now. A 60x40x4mm box-section tube fits exactly between the engine mounts and the swingarm pivot. Luckily I didn't have to alter my previous bracing. The tunnel has a thick wall to make sure the construction doesn't get weakened (and the chain will take a long time eating trough it ;-) Ruud from Postma Motoren welding it into place. The dotted line shows how the top part of the chain should run. With the swingarm-pivot tightly attached to the top tunnel it's time to make some room for the lower tunnel. Because the bottom of the lower tunnel is a bit narrow I added some extra bracing. Out comes my favourite 60x20x2 box section. And here's the tunnel welded into place. The angle between the two tunnels may seem large but their positions have been carefully adjusted with the engine and rear wheel in place. Here you see the bracing of the lower tunnel.