i original seen the idea brought up by chariot performance asking the HQ about dual piston calipers. so me being impatient, i cant wait for chariot performance. a few people have already successfully swapped out there banshee calipers with trx250r and chimed in on chariots post. i got the general idea of what was involved, but i jumped into this blind and came out on top. So heres what i did.
First off your going to need a round house banshee swingarm, otherwise this will not work. given you have the correct swingarm arm you will also need a trx250r brake stay, C ring puller, 4 washers, trx250r caliper, bench grinder and Hybrid rotor.
Step 1. you will notice when you receive you brake stay that there is a milled spacers on the surface. this has to be removed in order to fit on your carrier. i used a bench grinder and grinded little at a time until it was perfect.
after you grind it, it should look like this and fit like that.
Step 2. so after you have your brake stay on and you axle back on, you will notice your caliper will not bolt on. this is because the banshee brake hub will not clear the caliper, and modification is required again. i took my bench grinder and ground about a half inch into the alumium and made an arch effect.
Step 3. Step 3 should be pretty self explanatory. you will need 2 pairs of washers to shim out the caliper from brake stay, bolt your custom disc onto your hub, check your hubs clearance with the caliper, bleed brakes and tighten everything down and enjoy.
here are some pics of the spacing of the washers, and some various other comparisons pics.
and a few comparisons pics that i borrowed from the site.
my rotor was cut by JDS or 87sheerips, honda used a 7.10inc disc vs yamahas 8.5inch, this increases ground clearance while adding braking performance. contact him for your own! my purpose for writing this is to help out anyone whos fed up with yamahas shitty rear brakes. it always nice to have directions when staring a project so you dont have to learn the hard way, gl and enjoy