I have a few updates and upgrades to make on the Bridgestone. Including revising several items I've fabbed up recently. Such is life.
What I've realized is that my footpegs are too high, so I'm not comfortable on the bike. Way too much weight up on my wrists, and my legs are too cramped. Also, I had no real good way to attach a rear brake light switch to the brake lever I built. Normally I build a brake lever that mounts behind the swingarm, with the toe peg poking out below the swingarm and above the exhaust. Unfortunately, there was no room with the stock exhaust. So step #1 was to build a new exhaust.
The result is shown below. I used the spare header pipe and an expansion chamber I had in the parts bin from a YSR50. Since the YSR50 is a very peaky 50cc engine, this expansion chamber actually closely matches the dimensions Bridgestone shows for building a hot rod exhaust for the 90cc engine with a lower rpm peak.
Exhaust mounted up, just shot with some high temp black paint for now:
Tons of room for relocating the footpegs and brake lever downward a few inches:
I'll likely wrap the exhaust once I finish fabbing up the rest of my mods.