Honda VTR 1000 – Cylinder Head Repair

Honda engines have some weaknesses, one of which is the timing chain tensioner. While this issue is not as critical for inline engines, it is more problematic for V-twins.

The engine couldn't be turned manually, and after removing the timing chain tensioner of the rear cylinder, the suspicion was confirmed: the timing chain had slipped, leading to significant damage.

The tensioner spring had broken.

The front cylinder was in good condition, so it only required adjustment and a new tensioner.

I carefully disassembled the rear cylinder. Removing the valve cover:

Camshaft bearings:

I removed the cylinder head itself and observed heavy carbon deposits on the valves and in the combustion chamber.

In the cooling jacket, I noticed a piece of sealant, and on the piston, there were marks from valve contact.

Unfortunately, none of the valves survived.

I resurfaced the cylinder head, replaced the valve seals and valves, and reassembled everything in reverse order.

I also replaced the moldy O-rings in the cooling system:

After assembly and adjustment, the motorcycle ran smoothly and pleasantly, and its performance significantly improved.

As it turned out later, the first cylinder had been operating at 20% capacity due to a diaphragm in the carburetor tearing and jamming the throttle valve at an inconvenient moment. This annoying issue was successfully resolved.