OK, next thing on my DT2: dropping out of fifth gear.

RT325 mentioned checking the detent plunger which lives behind what i can now see looks like a second drain plug.

Now, if I remove that bolt do I need to have drained the oil first?

Looks like all that could fall out is a spring and cam plunger. If I clean them up should that have any effect? Clutch was gunged solid before being freed up by somebody who pulled it all apart and knows about these things, so wondering if the cam plunger and spring might also be gunged and benefit from a clean up?

Probably can't hurt to change the oil a few times especially if it was grungy.

You could lay the bike on its side... ignition cover up... and check the spring and plunger without draining but I'd just drain.

And I say "check" because it's not uncommon to find the plunger and/or spring completely missing.... many owners mistook the plunger cap for a drain plug and the parts ended up in the waste oil and thrown away.

Mark, this thread or/on another thread "a picture of dissembled and reassemble order might be helpful.

Thanks-

So, I removed the bolt and there's a spring but no plunger unless it is well and truly stuck in there, but after having a good old poke I didn't get a sense that anything removable was left.

Next question is where on earth do I get one...?

Google the Yamaha part number

Hi, yep, I have. Plenty in the USA, but none in the UK (where I am) or Europe. I'll try a couple of the UK bike breakers in the morning.

It may be there. Look up in there with a good light. It's a hollow sleeve. If not there, you should be able to see the detent cam on end of shift cam.

I had a good old poke round in there. I think if there was anything there it would have come out. It also felt like I was poking around a fair way in. There wasn't any gunge, oil was fresh from when the clutch was pulled apart and freed up, spring fell out immediately. What I made contact with when I was prodding had the feel of being substantial rather than small. There was also no tension when I screwed the bolt back in.

What I'm learning about this bike is whoever last did any work on it cut corners or didn't notice when things went missing - the missing washer from the needle jet setter being one example, an exhaust stud being another, the wrong spark plug another, wrong screws and bolts all over the place and so on.

It's been that sort of bike. But not for much longer.

If someone here has one loose on their bench, maybe they could provide dimensions. You could then get one made up - either do it yourself if you have a lathe, or get a local engineer to do it for you.

I think this plunger needs to be hardened steel.