Bad Maintenance Day for my 426

Yesterday, I attempted to install a new timing chain and a 03 450 exhaust cam on my 01 YZ426. Just before I took the cam cap bolts off, I figured I'd just check my torque wrench to verify that it's working properly. I put a spare bolt in a vice and set the wrench to 30 in-lb, turned, turned some more (shouldn't this be releasing by now?) and SNAP I broke the bolt. Maybe the torque was set so low I didn't hear/feel it release?

I figured that since my cover was already off, I could at least check the valves. I pull out my feeler gauges and realize I don't have the ones I need! I need smaller gauges to measure intake valves.

The good news is that my exhaust valves are still in spec: .205 mm, which is near the minimum allowed clearance, but still in spec! According to the previous owner, the valves have never been inspected or adjusted.

Once I figure out this torque wrench, I'll be doing the cam swap and from what I hear I'll have to adjust the valves anyway so I'll try to put them in the middle of the range.

At really small torque values, the click is really subtle, and not really even audible...you have to sort of feel it...

+1 on the torque wrench. 30 in/lb is next to nothing.

On the feeler gauges, I've never had any trouble using standard 4" automotive feelers in a 426/450. But if yours are wider, just trim a little off one edge with a pair of sharp scissors.

It's not that they're too wide, they're too thick. The smallest I had was 0.20mm, which is the lower limit for the exhaust clearance.

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