Engine quits at 65

Oldschool said:

I don't know if the R3 is a interference motor but it sounds to me like the cam chain broke and valves are bent (or the valves are stuck open due to cam position). Pull the air filter out and put your hand on the pipe. When you crank the motor check to see if you have air pushing back out of the intake pipe. That would be a sure sign you have bent intake valves or valves that are sitting open.

The fact that the motor spins faster than normal suggests to me that it would be likely that you no longer have compression. Just like if you pulled all of the spark plugs out and tried cranking the engine.

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Yes i agree with you. I will be sharing this information and helping him monday. will post results of our findings. Thank you for your reply!

If the engine is spinning "freer" than normal the first thing I would do is check compression. At this stage I wouldn't be too worried about the absolute compression number, but all cylinders should be relatively close to the same...say within 5% - 10% of each other. If you find that you have something weird like no compression on any cylinder I would guess that you have a valve train issue (I.e. Broken cam chain, etc) that is causing none of the cylinders to seal on the compression stroke. Although I will say that every time I have experienced a broken timing chain on an engine running at speed there was a significant amount of clunking noise as a piston came to TDC on a valve that was out of position. If only one is badly out of whack there could be other causes (valve problem, broken compression ring, etc)...either way...potentially expensive to fix. If all cylinders have good compression I would start looking at electrical first. Ignition switch, coils, etc.

One thing to always keep in mind...the bike was running fine yesterday and had done for 60,000 miles...start with the simplest stuff first before you assume the worst and dive off into an engine rebuild scenario. In this case make sure it is getting the basics...fire, air and fuel to each cylinder. Identifying those basic things may send you one direction or the other. Good luck and keep us posted

Although I will say that every time I have experienced a broken timing chain on an engine running at speed there was a significant amount of clunking noise as a piston came to TDC on a valve that was out of position

For sure, you would think that it would have made some sort of noise that would have suggested "engine blew up". The fact it turns over faster than it should makes me worry. I know for a fact that even with the coils and injectors disconnected the engine doesn't turn over fast, so clearly thats not a very good sign when it comes to compression.

I hope you are wrong for his sake, but your description so far certainly sounds like the cam chain

Please remember to keep us up to speed on what you find as ones trials and tribulations adds to the collective knowledge base and could save a future captain some troubleshooting heartache

Just to put it out there but it could be a broken cam - unlikely I know.
But to have it shut down with NIL noise or indication something was wrong and then to have no compression is a bit baffling.

Btw....we are just the "B" team. Maybe @warp9.9 @Rocket Scientist or one of the other internal engine gurus will speak up soon. I know Warp has broken more $hit than the rest of us combined and could probably offer a pretty good guess

...and just because he didn't hear a noise doesn't mean there wasn't one...

I would scope it before I try a compression check. if it is something like jumping time and you have not bent the valves yet why take the chance. Scope down the plug holes. And maybe pull the exhaust manifold away for a visual inspection of the exhaust valve stems. Of course if it was my bike and I suspected a collision I would not hesitate to have the cam cover off for a even more detailed inspection.

Sounds like a cam chain to me.