I figured I'd swap over my front HD rim and HP tire before the maiden run. Of course, when I did that the v-brake arms hit the mounts because of the wider rim. The rear v-brake also hit the mounting bracket, so I clearanced that too.
When I rolled the bike onto the sidewalk, I thought both brakes were locked! Then I remembered friction drag and when I raised both engines, the bike rolled well enough, considering the extra weight. There is massive amount of friction drag to take into consideration now, and the front engine assembly drags more than the rear drive. The new bike takes getting used to, since men's bike frames are at least an inch taller, and because of the extra 16 lbs off to the left front.
So I walked my bike to the nearby park and picked a remote location. The rear engine started with two pulls. The front engine started in three pulls and both idled well. I sat down for a 5-minute water break and let the new engine start the break-in. It sounded much crisper than the rear engine. Maybe because it was tight, and the mass of the lighter spindle allowed it to rev quicker.
In a couple minutes, I was driving down a medium-size hill using both engines. The rear engine felt weak. It took a few minutes of driving to warm up, and there's that extra resistance with the front engine idling.. When the new engine kicked in, I am SOOOO glad I chose the 1.25" roller instead of another 1.5" spindle. Acceleration is UNBELIEVABLE! The engine needed break-in, so I kept the revs reasonable. There is a definite major power boost at low and medium end with dual engines. It could be a number of factors that made the front engine more responsive, such as smaller-diameter spindle, HD rim and slick tire.
All was going well for three miles, when I floored the new engine and it immediately died. And it's still dead and unwilling to start. I yanked that pull start numerous times but it still won't start. Driving with the rear engine only was sluggish until I remembered the front engine resistance. When I raised the new engine, it was much easier for the rear engine to drive home. When the new bike charged up the medium-sized hill, it was much easier than previously, because the 7-speed option helped when the engine needed it.
Everything went well until the new engine quit. I felt the power of the dual engines, and it was awesome. If you start off with the front engine then kick in the rear engine, you can feel the little extra help. When you're at low speed with rear engine only, you can SERIOUSLY feel the extra help from the new engine and smaller-diameter roller. I only have three miles on the dual-engined setup, so I can't comment much on it. There's no smoke in the face from the front engine, and the extra noise at idle and speeds below 15 mph was very little. When the new engine breaks in, there will be serious power and acceleration available!