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twin engine blower bike

Sprocket

CB750 Enthusiast
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Location
Brighton, MI, USA
This is just in the brainfart stage right now, but I've been thinking about it for a long time.
Twin motor big bore, stroker, displacement should be around 1064 each.
Both motor will be without trans portion of case, crankshaft power coupled via HD style primary chain or belt (modern belts can handle a lot with less lash) Rear cylinder head will be reversed to keep intakes together and exhaust heat away from front motor carbs.
Motor/trans mounting will be via motor plates on both sides like a top fuel bike.
Trans will most likely be Lenco, it IS a dragbike!!!
No doubt it will be in a custom frame, digger/old school '70s dragbike. But the chassis will be built around the motor configuration, no adapting something else to "work with".

Like I said, I'm just in the brainfart stage of planning, researching cams for the reversed cylinder head (gonna write to Dynoman and Jay @ATI about that), clutch choices and of course trans ratios... and a bunch of other shit that I can't remember or havent though of yet...lol

Posts on this will be spotty at best until I start gathering the main ingredients of 2 motors so mockup can begin. It'll prolly take a year or so just to get the motors mocked up and into a chassis while keeping up on makin' a living, cool thing is my OL is all for it and behind me 100%. Love that woman!!!
In the end, I'm gonna want to do some LSR racing with it and ultimately a trip to Bonneville.
Not planning a full tilt race only bike either, I wanna rid this bitch on the street!!!!

Any ideas or thoughts on this are welcome.

I have 2 cases that are going to get cut tonight, and the blower (Eaton M90) is awaiting a little bit of TLC before polishing.
I need 2 cylinder blocks and one more head so I can get to mocking up the engine plates, blower manifold and injector bosses/fuel rails.
Once the major mockup of these is finished, I'll start building the chassis. BIG tire, 70s style digger dragbike.
The motor build(s) will take the longest and require the most dollars, so that's the last major thing I'll do.


This should be fun, entertaining, aggravating and an all around good time.
Hope you're entertained :D
 
This is going to be awesome! :thumbsup:

As things move along, it would be cool if you could post some of those pictures here with a little description under them. :)
 
Things are moving along. Cases are cut and sitting on the bench with the blower in approximate position.
Cylinder blocks and another head are on the way.
Motor plate mockup as well as blower mounting and intake manifold will be next on the agenda.

IMG_20120817_142114.jpg
cases cut, transmission buh bye!
IMG_20120817_142015.jpg
Blower inposition
IMG_20120817_142042.jpg
another view of blower in position
 
I thought I posted this 2 days ago..lol
I cut them with bandsaw, need to bolt cases together to finish machine the final surface for the blockoff plate.
I also need to weld in some threaded bungs to bolt said plate to as there's no existing holes to use.
 
Juggs and head should be here tomorrow!
Gotta run to Portland MI to pick up the yammys I sold @ BBB (gotta deal with customs before I can title them) and make it back before the post delivery.
Going to Ubly to race the chop, so nothing this weekend.
I'll get a few pics tomorrow with the juggs and heads on for those picture junkies around here
 
Got the jugs and head today and set it up for eye candy.
Enjoy.
 

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So I thought the cased would be oriented the same way and the head would be flipped on the one?
 
Now that it's coming together (the major mockup parts) it's time to study and learn and design.
This has a lot of issues that need to be addressed and a lot of work to make it happen.
The rear motor WILL run the correct direction and the head will be reversed.
For now, it's easier to visualize the overall with it flipped around. More to do with how it sits flat on the sump cover surface than anything else, it gave the V angle for me to see and fit everything into place, or at least verify that there is room for what I want where I want it.

I need to machine a pair of dowels to crank journal diameter, and set up the motors off the table on V-blocks for the first round of MDF mockup motorplates. That will get the motors off the table and allow me to rotate the motors (on the "crank") to the correct position, and locate motor mount holes in the plate.

I'm looking for some engineering drawings of the motor so I can work out the changes and save some measuring time on old parts. Lots of machining and fabrication before the motor builds are even close to starting. And more questions come up every step of the project to be answered or worked through.
 
This is the inspiration for this build. The bike pictured is being restored and will be raced against RC's other bike, the triple engine nitro injected Atchison, Topeka & Santa Fe bike, which is also under reconstruction/restoration.
The triple crashed @ 170mph, Russ Collins designed the Sorcerer while recovering from that crash that almost killed him.

RC Sorcerer.jpg
 
I've worked much of my fabrication career in automotive prototype.
We had access to some cool stuff back in the 90s.
Lots of good parts slated for scrap. This blower has never ran. It sat on a shelf in my friend's shed for 10+ years...lol
I finally talked him out of it for a song.

There will be a mounting bracket for the blower which will connect the end plates between the motors for a solid blower mount.
Oil pump should fit beneath that.

I'll cut, weld, and machine the throttle body flange to point in the opposite direction (forward on the bike) and I need to decide what throttle body I want to use. Maybe a GM 2bbl from an LT1 or other MPFI setup.
 
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