I understand that this is a website wholly dedicated to VINTAGE yamaha enduros, but could I get some opinions on this. My rt180 has one of the infamous oil injection systems. I continue to rely on it because it's never failed me, and continues to work great. However, the first three days I had the bike, we had a problem. The oil pump line to the CARB became disconnected, and it ran without oil for three days. I found out, basically lost my shit and thought I toasted the motor. It actually popped off again during my ride today, which for certain means new oil lines, but the bike actually worked fine and still has good compression. What the hell? I figured it would've blown up by now. Should I be worried about any failures? It still seemed to smoke blue just fine, so I'm actually confused. The pump doesn't actually go anywhere other than the carb.

RT180 is a very close relative to the 78-81 DT175. Several parts interchange... it's a "dirt bike" version of the street legal DT version that other countries got.

In fact, your oil pump is the same part as a 1976 DT175 pump.

Anyway, seems odd that it ran without oil for three days with no ill effect. And kept smoking? I'd check your trans oil level. You might have a leaking crank seal that's allowing some of the motor oil in the trans to get sucked into the crankcase.

Off the top of my head, I can think of two reasons why that oil line would 'pop off' its fitting (I assume on the carb, not familiar with that model). One is that there is some kind of tension on the line that's pulling it off, like maybe someone cut it a little too short. Solution is to replace with a longer line.

The second reason is that there is something blocking the line (inside the carb?) past the point where the line attaches to its fitting, and the pressure of the oil in the line is pushing the line off its fitting. In that case, there is likely NO oil getting into the combustion mix at all - ever! My solution to that is to poke something (a fine wire?) through the oil passage until it's obvious that the obstruction is no longer there.

Yes, all of the above or pull the carb off & eyeball the wire coming out the fitting in the carb [or manifold--wherever it feeds in]. But originally there should be a roll spring clip [thing] that holds the line tight onto the fitting & can't imagine it popping off if that was in place. Often if the line has been off for some reason the roll thingy can slide down the pipe & be almost invisible sitting there.. Might be a good idea to run it for a minute & watch the open line pump oil out. Just squirt a bit of oil in the fitting so gets some to the crank/cylinder for a minute or so. Also it pumps very little unless you pull the cable at the pump while you're running the motor slow/fast idle or a bit more. & temporarily block the fitting while you're doing that or it'll run lean & revs will creep up. Sorry--few words turned into an essay.

Thanks for the help! I ended up replacing the line. Ironically, this bike just got new seals. The first three days, it definitely had a blown gearbox seal, but after the second time running with the oil line off, there shouldn't have been any oil going into the motor for a while. Still has 150psi compression. I'm just suprised that I've yet to see any ill effects from all this.