The Dual Fuel Drop Loop, or Pig Iron Pete

Forbidden Tuna

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The closeup pic shows the two tacked together. It's 3/16" plate. It's still thicker than any pedal bike dropouts that I've seen personally.
Luckily I can still comfortably fit a standard coaster wheel with enough thread bite to where the nuts have full purchase and then some. I'm using an old Shimano cruiser wheel which was good enough to stop me with my 79cc huffy bike but seeing how this one might be a bit heavier I wanted the band brake as a backup so I don't burn up the coaster. I guess one big advantage of the sprocket adapters is they kinda act like a heat sink for the hub.

I don't have it added yet but my jackshaft will be on the frame directly. I have a pair of 2 bolt flange pillow block bearings and it looks like all the reduction gears will be between the bearings, seems pretty stable to me.

I kinda want to build a kick start mechanism, I have some 5/8" bore 1 way needle bearings and I've seen how some folks have made kickstarts using two thin sprockets and chain.
 
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Forbidden Tuna

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I've pretty much decided on the final aesthetics of the bike.
It'll be somewhat of a blend of a 1912 Henderson with the side mounted floorboards of a 1916 Henderson Short Frame style. Kind of an anachronistic idea of if Henderson sold a Short Frame model of their 1912.
I have the idea of making an elongated fire extinguisher gas tank, I'm hoping to get a fuel filler neck for Harley bayonet style gas caps just for my own sanity and not needing a funnel to fill it up.
The backbone extends almost straight from the chain stay and has a 180 degree bent middle tube. It'll look a little funky because I'm using a bigger backbone than the middle tube, it's only purpose is to support the cylindrical fuel tank in my situation.
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Note how in the top picture the 1912 it has a very forward floorboard. I'm 6 feet tall and even I think that's a bit of a stretch. I like the side boards on the Short Frames from what I've seen. With that 196cc Honda I will have a bunch of room up front so I can keep a battery box or something like that. I will be attaching lights to the bike and I might try my hand at disguising them as carbide lights.
Really wondering how hard it will be the remove and attach the wheel with horizontal dropouts and a full sized fender. My donor fender is from a very sturdy Murray cruiser, I just need to reinforce the supports.
Front fork I'm not sure if I want to try to recreate the Henderson fork or just build/buy a girder fork.
 

Forbidden Tuna

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Got the 24mm Mikuni copy mounted on the engine. I wish this flywheel was flat instead of having integral fan blades so I could leave the engine without a side cover. Don't want to catch my pants on the blades though. Maybe with a different build.

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I'll be building a new exhaust for this engine, something that flows straight back.
 
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Forbidden Tuna

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Mocking things up. I actually might have enough room to use an original style Henderson floorboard. By the way I'm using this belt sheave mounted wheel because it's the only spare rear wheel with a big balloon tire on it so I can guesstimate where I can mount the rear fender.
The rear axle has plenty of bite on the dropouts. Using a big nut and a washer on each side evenly.
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I'm using random crap in my shop to counterbalance the front end since I have the rear wheel hanging off of the table.
 

Forbidden Tuna

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My drivetrain is going to be pretty simple and upon Tony01's advice I'm going for a V belt primary and chain drive. 4" pulley going to a 7" sheave, driving a 10t Maxtorque centrifugal to a 48t sprocket on the wheel. 8.4:1 gear reduction. Haven't tuned the carburetor yet, need to size up the main jet just a smidge. Assuming the rpm plateaus at 6000rpm due to valves floating it gives me a top speed of 55mph according to BMI Kart's MPH calculator. More than enough for me.

Might try to get a self exciting v belt alternator so I can power lights and whatnot. Engine isn't electric start but it's not a hard one to pull over, no big deal.
 

Forbidden Tuna

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I've been waiting for a plasma cutter to come in so I can do more annoying cuts with it. It's finally arrived.

I'm going to show you guys how you can build this downdraft charcoal gasifier and also how to build a simple updraft charcoal gasifier for a small engine. These will run a generator no problem and run until the hopper gets near empty with no issues.

This weekend I'll be building most of the down draft reactor, but this afternoon I'll draw up a simple updraft unit.

The updrafts can be built with little to no welding. In fact one of my experimental designs ran on my truck with only exhaust sealer covered with ultra red silicone rtv before I was satisfied with the layout and welded it into place.
On the other forum I frequent we consider charcoal reactors to be an open source idea because it can be beneficial to people that need power in an emergency and they're safe to work with provided you don't leave them indoors when running(carbon monoxide).
You can build one out of steel and cast iron plumbing parts.
I'll be drawing it up in paint.
 

Forbidden Tuna

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Cody's Generic Updraft Charcoal Gasifier.png

Here is a super abstract drawing of a charcoal updraft gasifier. You want two containers with lockable lids and heat resistant gaskets. I used for my truck a 55 gallon drum with a fireplace rope gasket ultra red RTV'd into place to the lid, and I used a tall ammo can and covered the neoprene gasket with the same RTV. Permatex Ultra Red is good up to 600F.

For nozzle size, we've figured it takes a half inch sized nozzle for every 500cc, you can oversize for your engine it won't hurt anything. Might be a benefit and make richer gas. For my 2 liter Mazda engine I used a series of holes making the pipe look like a flute.
If you make a simple nozzle just coming into the side and not pointing upwards it will burn away, but if you point it back upwards with a 90 degree elbow it puts the nozzle below the extreme heat. The reaction is endothermic because the fuel is also it's own insulator from heat. You have a small lobe of anywhere from 2000F to 1300F depending on if you use water drip or exhaust gas return to cool down the reaction. Water drip is beneficial because it turns to steam when it hits the hot nozzle, then as the steam passes the lobe it cracks into hydrogen, a small amount but it still helps, as well as brings the reaction temps down.

You want the upwards facing nozzle as close to the center as you can get it, but it doesn't have to be perfect. This is just to keep the heat as insulated away from the barrel and keeping it from getting hot.

For my gas exit of the main barrel I welded in 2" thin wall conduit, with about 4 inches protruding either side. I wrapped up a cylinder of hardware cloth and hose clamped it down, this keeps the little charcoal bits from flying into the filter and being a general annoyance.

For a small engine you could use 1" plumbing pipe or conduit. I will be using 1" conduit for most of the gas routing for this bike.

The gas exiting an updraft usually isn't super hot but you should still use a metal line to connect to the filter where it will be ambient temps. I used 2.25" flex exhaust hose, RTV then exhaust clamped into place on the conduit pipe studs. I used the same conduit for the bottom and top pipes on my ammo box filter. With the gas coming in from the bottom it lets the heaviest soot settle to the bottom, leaving only the finer stuff to get caught by the sack/bag filter. In a mobile unit the soot being collected on the outside of the bag allows it to be shaken off by bumps in the road. After the filter you can use PVC pipe because the gas is at ambient or below temps.
The added benefit of a sack filter is if you have poor quality charcoal and it produces tar, it will clog up the filter instead of your engine. To clean a sooty filter I just take it out and shake it. You would probably need to machine wash one that had tar on it.

For an air mixer, you can use a simple ball valve. I find the brass ball valves move easier than stiff PVC ones. Your fresh air filter should go where the ball valve is. If you have a Honda 196cc with the stock carburetor, you can use those pod filter adapters and attach the charcoal gas with rubber boot connectors. Some guys have used shop vac hose but I've never had luck with them, they're leaky and bring in too much air making it run lean. Most hardware stores sell rubber connectors that are made to fit both PVC and metal plumbing pipe, I use these combined with PVC pipe to route to the engine. You should check for air leaks by blowing air into the unit and spraying soapy water, and patch any leaks with red RTV. The system is under vacuum when running so it isn't dangerous to have air leaks, it's just annoying and can make the gas not strong enough to run the engine or give poor performance.

To start this unit up, you can use a shop vac or a mattress blower using the suction side. A handy place would be at the air mixer with the valve set wide open. Turn on the source of vacuum and use either a propane torch or some burning paper, one guy uses fiberglass rope soaked in just a little kerosene held by a long wire to light his. You should see a glow pretty quickly, dry charcoal lights rapidly. Once the unit is warmed up you can introduce water drip, I use a small petcock valve on a rubber hose with a stainless steel straw at the end and place that straw inside the nozzle pipe. You want about 1 drip per second for a small engine.

To see if you're ready to start the engine, take a match or lighter to where your vacuum is exiting. You should see a mostly blue flame. Don't worry if you see purple or a little red. Typically you're ready to run the engine after 5 minutes of warming up.

This is where having electric start would be handy. Close your air mixing valve almost all the way, just barely cracked open. You could fill your float bowl with gasoline and then shut off the liquid fuel supply. The engine running provides vacuum demand on the gasifier, so it's only making gas as long as something is sucking on it. With my truck I usually would start on gasoline to both light and warm up the gasifier and once I noticed it was running really rich I would shut off gasoline supply and let the float bowl empty.

Hopefully once gasoline is used up in the carburetor it will transition over to pure charcoal gas. If you have a lot of air leaks you might have to close the mixing valve even more or close all the way. If that's the case then you should find the source of the leak.
Woodgas and charcoal gas really like high compression engines, it can withstand up to 18:1 compression before knock occurs. They also like really advanced spark timing. Carbon Monoxide is a very high octane gas and resists knock like crazy. I adjust my distributor on my truck all the way forward and all it does is smooth up.

If you have any questions let me know, I just wanted to share the process of how it works.