Bought in November in questionable condition. Spent the last 10 weeks pulling everything apart, had frame repaired and coated, installed new cylinder studs, fixed wiring, cleaned up tank, set the valves, undid decades of questionable repairs and errors, etc.
This weekend I finally got a plate, and started some test rides to sort out the carbs. I had an ongoing issue where the idle would either hang hot or cold, or die when hot. But it was great once on the needle and mains, so I rode 100km to work and back, with a few stops to fine tune the idle mixture screw. I thought I had it dialed once I got there.
On the way back in the rain, things slowly started getting worse again - this time, bike would die when off the throttle. Suspected maybe fouled plugs, maybe choking one cylinder due to the carb synch screw being off, maybe ignition issue due to water or something. I could keep things going if I kept the throttle on a bit, it was raining, dark and cold, so I rode home.
Opened the air box to find this
The lid was on properly, but I think the clamps are a bit weak. There are marks on the tank so maybe the tank was pushing on them, either way it obviously lifted enough for it to fill with crud and sand from the front wheel.
I had some hope at first that the rubber snorkels had kept most of the sand out of the engine, but then I pulled the plugs. I'm pretty sure I can see scratches in the cylinder walls and some grains of sand on the vertical piston. The horizontal cylinder looks better (at least viewed through the plug hole), but the plug was oily. It had been dry when I last checked it 100km before while at work.
I'm pretty deflated. I guess I could do compression/leakdown first, cranking it with the starter I feel like it has lost compression for sure, but maybe it's just my imagination.
The engine will obviously have to come out again even just to make sure no sand is left in the cylinders. Then I'll see what the damage is. I was planning to save this years bike budget for some FCRs, now I may be looking for a donor engine instead.
And my neutral light stopped working, too.