Tear-Down: Phantom 85 with MS-460 Piston 

Thank you!

You have one?

Thank you!

I'm glad you are enjoying the videos! Rest assured there will be some YD100 mods in the future.

I did not check the ring end gap. I agree with your comment with one caveat, cutting through logs is definitely not a minimal effort task. It's WOT for much longer periods of time than you would expect; certainly no different than the 40 seconds of WOT that it took to blow up this engine, if the log is big enough. In any case, these engines fail in a similar way with the stock piston as well. The issue appears to be an inadequate amount of cooling fins, which yes, based on the damage, it does appear that the rings end met up.

I'd argue that since it's on a bicycle, with no shrouds its getting better airflow, maybe though not as forced. And we're traveling at speed too, however, these engines are designed to be short burst power, not continuous burn running. You have to use the motor in the condition it was designed. I live in a small, valley town in Appalachia. To get up hills and ride (especially in colder months) is so fun and the phantom does it well, but to run flat by the river for extended amounts of time is not where this motor excels. Though if ran right, maintained speed can be "easier" on the motor, this motors failure was due to improper use. If your motors hot already, load a heavy burn on it, you can expect a failure. When riding these bikes you always have to keep in mind it's temperature.

Ooof! Yeah, that's toasty. It would be nice if someone made a liquid-cooled jug for these engines.

Best time to run them is objectively the worst time to ride. They love colder weather, but I damn sure don't!

@@christianhunt7382 I heard that a cold front hit Texas it was 30 and sleeting didn't stick already in the 40s but that will be it tell Tuesday then it will get better 👍

Based on my short experience with this engine, I wouldn't recommend it. Reliability concerns aside, the engine was very buzzy and uncomfortable. It also seemed to only want to go fast. So, for my use-case of cruising around town, it was not a good fit.

Yes, I believe so. LA Hover Bikes swapped the piston. Check out his channel for more info on the build.

Link in the description.