[Thumper]

AJ1 (https://aj1moto.com/) has a variety of engines, including the twin cam ZS NC300 liquid cooled engines (280cc) shown here. They do have the ZS174FMM-3A (OEM 5-speed on the original Temp X and now on the Temp M). It is a great engine for off road, no counterbalancer, but easy to work on/mod.

This NC300 won't fit and you'd obviously have to add a radiator!! But at the moment, a TempX frame conversion would be one way to own a Zuumav NC300!

The K8 motorcycle is offered on the AJ1 website for $3900. It seems like you can equip it with the NC300 engine!

Originally Posted by Thumper

I like the ZS172FMM-3A (5-speed) for it's simplicity, and for a dedicated offroad bike, it's adequate. But the 6-speed version with counterbalancing is also available for about the same cost. Amazon has at least one source for the 5-speed, and ebay has a few sources including the 6-speed.

I can hear the counterbalancer linkage in the 6-speed whining (not loud, but audible). I am sure it is normal. That extra gear is useful, and the counterbalancing is nice for road use, but the 5speed might be a better choice for an offroad build. The choice is not that easy for me

As you can tell by the triangular right case shape, and the absence of a kick starter, this is the 6speed. It even comes with a gear shift and a starter. The real benefit of paying the additional ~$450 (more than the cost of a head) is that you can do a complete bench build and swap it in when you are ready. And the head in the complete engine includes the cam/rockers/camchain sprocket/camchain...

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