Cannonballs Abbynormal 3Speed.

Thanks for all the positive comments everyone!
Cant wait to get it going, just waiting on parts to finish the bike. This was an engine only and not a kit so am having to piece stuff together.
And truly as RC says the devil is in the details.

LSR, to which side do you need to move the hub? It has a small amount of side to side adjustment but NOT MUCH. You can add/subtract spacers to the driven sprocket to shift the hub around the CGs chain line which is locked in by its mounts. The hubs spoke flange is used to hold the driver sprocket. Shifting the hub moves this chain line. It just depends on the bikes frame/wheel combo how much movement it will tolerate. The MTB wheel I used is dished flat on the pedal side and inward on the engine drive side achieving the clearance for the hub to wheel drive chain. Most of the adjustment would be to the right with very little to the left.

Run a skate wheel idler on the pedal side lower chain run. This chain is used the least(might not be so true in your case) Is most important to have good adjustability on the engine drive chains, don't want to throw one of them at high speed! Since the pedal chain only travels loaded in one direction on a freewheel bike the slack bottom chain is easily tensioned with an idler. There are manufactured idlers available for converting multispeed bikes to fixies to do this very thing. I have one on a build and it is very picky about alignment. The skate wheel is not, plus its quiet and durable(a plus when used on the engine side). I will be running one on this build for the pedal side.
Mapbike said he makes one, PM him and see what he has. Its a simple thing to make a bracket to mount the idler. Don't worry about spring loading it.

If you look closely at the hubs mounting in the pics you will see the lock collar mountings. These allow you to get the ultimate setting on the initial chain set up by being easily movable, The hubs mount is also slotted for fine adjustments. I set everything up (hub/back wheel) bottomed in their adjustments so I have plenty of adjustment over the chains life.

I want to be sure at this point every one knows you are on you own on the inner driven sprocket. The hub was never intended to be used this way, so there are no ready fit sprockets available, The reason the hubs sprockets are so large is to accommodate the hubs diameter. 23t is the minimum for the inner. The outer driven sprocket is a stock Surley fixie sprocket of 22t. These are easily obtained in many different tooth counts to change the ratios. The back wheel on my build is slightly overdriven(22t driving 23t) This is not really an issue. I just found a deal on the Surley 22T.

If you hook up the engines in parallel is it still a 50cc(electrical joke)-lol.
The problem with shimming the engine will be upsetting the engines chain tension to accommodate the pedal chain unless you can add/subtract links in/out to make it work-never seems to happen that way.

Stuff to complete the build is due in the first of the week(hopefully). Paid some big$$ for a genuine SA thumb shifter. The bar end shifter seems too awkward. Will be using a double pull brake handle on the right and the clutch and shifter on the left.
I had a new friction thumb shifter but its not indexed like the SA and I don't want to hunt for gears. Im thinking of clutching between shifts like an M/C if I can do both at the same time. Maybe just backing off will do, but the hub is still loaded in reverse flow then(engine braking).
Starting will be done in high(locked 1:1) to ease the load on the planetary gear. Once started, just shift to what ever gear is desired. Im digging the fact that an IG hub will shift sitting still. Just come to a stop and shift from high to low sitting there.

Way Cool!! Im wanting to build a carbon frame in a real BAD way. Been watching the prices come down, so maybe one day.

If you wanted to make it a 6speed you would need to use the first 3sp as a jackshaft and
transfer it 3sps to the chain ring/rear wheel in the normal shifter bike fashion. While you could constantly shift both sides as a 6spd it would be easier to use one side(probably the secondary) as the shifting side and the other a range side It would really offer a broad range. Imagine having the primary(engine side) in low that would make the other sides 3spds rock crawling capable, with a midrange, probably the one to stay in(even though its running the planetary) for normal operation and a high range to haul a$$(probably have to shift in to this one at high speed). Great idea, just takes about $300 worth of hubs. If it would work as theorized that's really a bargain.

I saw really nice used carbon road bike frames on ebay in the $200+ range, have to save my nickels.
Stuff will show up today to get this build finished. Except the dang handle bars! Gonna be sitting til the middle of the week waiting, and the temps are gonna be in the 80s!

This is a bone stock engine build, its more about the hub on this one. I have figured ratios on mild engine rpms(6500) if it will turn more it just gets faster which I wont complain about. Its geared for 32mph@ 6500. Have to wait and see.

All this info is great to hear!
I have a pull start I bought to use when I was considering running the Shimano backwards. It would have freewheeled when trying to start.
The teardown vid of the S3X showed a large three eared drive that locks the hub to the drive. When in high(third) the sliding clutch has a large face the locks the planetary gears and the loading is carried through the gear case not the gears. I feel it will handle pedal starting ok. Staring in third is a must I believe.
I finished the shift selector yesterday and ran it through the gears while pushing the bike. It was pretty cool watching the chains traveling at different speeds then finally the same speed in lock up. The chain lines are perfect with smooth flow. Should be a nice ride. It may operate better with an auto clutch. Shifting might be easier just by backing off. I may go that route.

Cool stuff LSR!!

Got the bike 99% finished today(yeah right). Stole a set of handlebars from another bike to complete the build. Should nickname this things "cables" its got a bunch of em.
Everything fit and worked well. Had to run the very awkward bar end shifter. Made clutching/shifting difficult. Top handlebar mount will be here tomorrow.
So how does it work? Id say perfectly! It pedal starts no problems. I start in 3rd as the load is carried through the outer planetary carrier and not the gears. As soon as it is started you can down shift to what ever gear you want. It shifts with out clutching just by backing off, but is much better clutched. The overall ratio is a bit low, should have gone to a low 30t rear sprocket instead of the 40t. The spacing on the gearing is good no big gaps. I REALLY like BMX chains so smooth and quiet. One of the nicest things compared to other shifters is there is no chain lash and or freewheel take up. Feels solidly linked to the rear wheel.

Next great thing is the GT5, my first one, its a super smooth engine. I don't think it could run any better as a stock engine, I did clean the ports and match the transfers. This is the $60 ebay auction, engine only. Im super impressed!
Will spend the day tomorrow tweeking a few details and waiting on the new shifter to get here. This has turned out probably better than I expected!

Yeah I know, hold the comments on the p-nut tank.