Apart from choppers and bobbers, when you see a really nice build it's the tank and tail that stand out as the key element for obvious reasons. Besides being a part of the bikes ergonomics it gives the bike it's flow with it's line and form. I thought I'd just focus on the tails sections this time, as if you're trying to build something to a budget, the tank in most situations will remain.
There are a number of directions you can go with a tail section. These are my observations anyway so take them with a grain of salt.
Pretty common for cafe racers. Great shape for storage especially for electrics, and a small tool kit. Most are built with an integrated tail light.
An example of an integrated tail light with what looks like a separate seat pan.
Inspired from the original dirt trackers.
Seat of the dirt track xr750. Has the seat cover attached over the tail, have seen some with the number plate covering the frame triangle to hide the electrics.
Flat seat often found with a rear frame loop. Also seen on street trackers. I really like the rolled leather look, also good for two up riding.
Like the piping on this matching the lines of the frame
Looks like a nitroheads seat with indicator tab welded onto the frame loop.
This is very broad overview on the different styles. If anyone has any other subcategories let me know. Didn't add the bobber or chopper styles as they normally feature a single seat and fender.
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