404 CC Banshee Build Complete

[SleepyKeys]

Over the last week I managed to rebuild my Yamaha Banshee. Pics below, comments welcome. Nothing too exciting, I rewound the stator, welded the crank and milled the head.


All the parts ready for final cleaning and install


Nothing a little magnet wire and epoxy cant handle

Case ready to go, looks pretty cool, amazing how compact bike setups are


Word on the street is that cranks walk/twist when abused so I figured I would fire up the tig for a min or two.


Fired up, sounds good, lights are quite a bit brighter. Just need to take it out tomorrow and dial in the jetting(needs a nice mass-air setup, maybe someday).

[gimpy]

Sean is that the same bottom end that was used on the RD series? I had a 400,was just scary fast for a 400 cc bike(I thought of it as a Shwinn,with a small blk. in it),always wondered if a fella could put a bike trans. in that case,have a water cooled RD.Thats a really scary thought Gimpy

[SleepyKeys]

Yes I believe it is, I think they used most of the RD stuff to make their ATV version cheaper. The water cooled RD, had power valves which would be nice sometimes, but isn't all that necessary. You just have to work the gear box a bit more. The porting is quite dated, that's why I put bigger sleeves in it making it 404cc. Picked up 15hp.

[gimpy]

My 400 air cooled had reed valves in it, helped the power band below 3000,didn't have that boog @ low rpms. 15 horse is a nice bump,what carbs are you runnig or are you injecting it? Gimpy

[SleepyKeys]

I'm pretty sure you would have to use a MAF to calibrate alpha-N tables as the WB02 reading would be worthless on a 2 stroke. Maybe in the future, but for now it has 2 35mm carbs. Reed valves are different from power valves. Power valves cover up part of the exhaust port at lower engine speeds so less of the intake charge gets blown out the exhaust port.

[gimpy]

Oh yes my bad,The RZ series,I've seen one or two of those never owned one,LOL Yep it would not proly work to use a WBO2 on a 2 stroke,I had not thought about that,but because your posted here I kind of wondered,injection on a 2 stroke would clean up a lot of carb woes.Gimpy