Rebuilding the banshee motor

[pondtunes]

12 O clocks got you covered.... I would suggest sending your stock carbs, timing plate & head to a builder to modify. Do you live by a small airport? If so: Recon over there and see if you can buy 100LL out of the pump. Have the timing plate notched to advance it 5 1/2 degrees.... with a modified head and the carbs dialed in it will wake that pig up in a hurry.

 

Theres a builder here in AZ that builds a nice package for Av-Gas with stock modified carbs, head, timing plate (same one Im running), His port, VF3s and T-5s that makes 70hp... Assuming your crank is still solid, you could have it welded up and build a nice reliable motor for a reasonable amount of doah. I'm sure our site sponsors have similar packages,

 

I stripped out a stud on my bike and had to drill it out and drop a heli-coil in... it was a little nerve racking but no issues at all.

 

 

 

I can buy 110LL AVGAS long as my gas can has AVGAS written on it The cost is about $1.32 / gallon more.. That being said is there a formula for knowing when you'll need that much octane? What kind of compression would I be looking at with a fresh bore, new rings/pistons, 5 1/2 deg timing advance?? Dune port & milled stock head any way to guess?

[theeechozen1]

On a stockish play bike I wouldn't go lower than an 18cc dome or equal... I run 19cc domes with a +5 1/2 advance on the 100LL without issues. Im pretty sure I could get away with 18's on the 100. There is no need for 110 on a play bike... Im sure a performance shop could cut your head for 110 if you really wanted. But your bike will start to lose some over rev with that much compression. It will rip out of the hole tho....

 

I recommend setting it up on 100LL

 

anything more than 40 off the stock head (about a 21cc dome I think?) and you will have to have the head rechambered to clear the pistons