Looks like my dream project is going to happen. I have found a package deal for a 1984 ATC 250R(blown up) and a 1987 Banshee(also blown up) The price for both is $2800obo. Is what I want to do is stick the banshee motor into the ATC frame. This would be strictly a drag racer. I think it would be trick to have drag pipes come out both sides of the trike! My only problem is that Im not sure where I would place the radiator. I dont think it would be a big deal in the sand, but the drag track we run is more dirt than sand, and they keep it prety watered down, IE mud. I suppose I could offset it a bit to the left, or maybe adapt some 85-86 ATC 250R radiators to the 84? Any ideas? Thanks..

RoostKing...

 

Finding a spot to mount the radiator shouldn't be that big of a deal if all you're doing is drag racing. Just about anywhere will do. If the '84 frame is similar to the '85-'86 ones then I'd use that radiator. the '84's were air cooled werent they?

 

Yes, the 84's were air cooled. I am going to be going to a friends house this weekend that has an 84 frame so I can do some measurements. I have been told the engine compartment area is not big enough to house the banshee motor. If that is the case, I will have to rethink this project , as I dont want to hack up the banshee frame to make this work. I might get the package deal, strip what I need off the banshee, get the 84 running,(it only needs a topend) sell them both and find an 85/86 frame. I have been told the bansheee motor will fit in this frame and it will also solve my cooling problems. Keep the ideas flowing!..

RoostKing...

 

Nothing new here. Harry at Trinity Racing was the first to do this in the very early 80's using RD 350-400 engines.

 

I'm going through a similar conversion now. I'm taking a DS7(twin Cyl. 2-stroke 250cc.) and converting it. I'm going to put a 200X swingarm and triple tree on the motorcycle frame. That way I don't have to do any hacking. The only thing I'll have to fabricate is the rear shock mount and the fender mounts. We've done a few of these conversions and they work pretty well. Of course, there's always some fabricating to do. The hardest part is getting the pipes done. This bike is air cooled, so a radiator is not a problem. Keep us updated, I bet that Banshee motor on a R is going to be killer!

 

If you would be interested in a big bore, I think the FL350R jug is the same pattern if the head bolts do not hold the ATC cylinder on. The FL350R is also air cooled. They normally run hot with mods, but should be fine without a seat in front of the cylinder.

I can measure the bolt spread if you like.

 

I have passed over many A-arm framed, 90-94 blown up banshees in my area for $1000-$1300. That is the typical price here. J-arm framed bikes are hard to give away. What I would do is find a banshee motor and a Tri-Z frame. This is a trick setup and it solves your cooling problems. I recently sold my 85 tri-z for $700 and that is average for a running one around here. I have heard this is an easy swap.