today i used a parts 350x to build the new pipe for the nre 350x... i used a stock xr400 head pipe,. bigger diameter than a stock 350x and its stainless steel like the 400ex. it bolted right on without a single issue, so then i added a nice carbon fiber can that i have been saving for just this reason,,,, it fits perfect .. so as soon as i get the motor in the new trike ,, the pipe is already done.. with the exception of cleaning it up and polishing it up.... also i am going to use a master cylinder off a newer yz450,, it has a built in resiviour so i eliminate a few things,, it will bolt on where the stock master goes and hook right up to the pedal.. so far the only thing i see is it has a smaller diameter on the cyilnder,, not sure if that will effect the amount of pedal travel necessary to activate the brakes properly yet or not,,, i guess when i get it all juiced up i will see,,,