Micargi Seattle Hybrid

[Forbidden Tuna]

Finally got a new project in mind. I have this Micargi Seattle Single Speed frame hanging around and a 36V hub motor. I have a buddy building a decent capacity battery for me on its way so I'm just prepping it for the build. I have a Monarch style disc brake fork, and my own freehand bent handlebars from some black iron pipe. The tires on the hub motor are temporary, I will be replacing them with some Fat Franks. If I can fit it I'd like to put a stock 212 motor on, but I'm thinking a 4 stroke 50cc will be more realistic.
Sprocket is mounted to the disc brake. If I can fit a Predator then I will use a band brake on the clutch bell for a rear brake.

 

[curtisfox]

How about a small disk brake on a jack shaft.............Curt

 

[Forbidden Tuna]

How about a small disk brake on a jack shaft.............Curt

That's a good idea, I didn't think of that.

 

[curtisfox]

Yep do to the reduction gearing of the sprockets doesn't have to be very big...........Curt

 

[Forbidden Tuna]

One question I'd like to ask is that I want a pretty low gear for my pedalling. It has to be a single speed because I have no interest in a derailleur or fabricating a mount for it on this oddball dropout. I recently ordered a 16 tooth rear freewheel sprocket, would a 36 tooth sprocket on the crank give me a decent low range?

 

[curtisfox]

Should work good......Curt

 

[Forbidden Tuna]

Little update:
I'm thinking about using this Lifan 79cc engine as my gas motor, been having issues finding a replacement carb that uses a slide style until I messed around and mocked up a 3d printed Predator 212 filter adapter. Seems to fit just fine so I guess I'll get a Mikuni clone kit in a 19mm size and adjust the angle for the studs.

 

[Forbidden Tuna]

Been testing the ebike portion with a little 36v battery I keep around. Still no brakes but my driveway is 1/8th of a mile so I just apply the Flintstones Brakes. I had to use a multi speed freewheel instead of a single speed because I'm not using a Fatbike motor wheel so my chain alignment is awful. It's mitigated a little bit but I'll need to add a tensioner to keep it from falling off or surprise shifting to another gear.
Found an old white vinyl Troxel sprung saddle so I just had to use that. I let the metal parts sit in a bath of Evaporust and they're good as new.
Modified a kickstand to fit this low rider as well.

 

[indian22]

Have you decided on how you'll setup the Lifan's drive train?

I've seen this frame with a 212 predator in the unmodified horizontal cylinder position and though I prefer the vertical cylinder look in most bike frames, the horizontal looked really good in the "stretch" Micargi frame.

Also some food for thought the 36v. can be and often is coupled to a 48v. controller and 48v. lithium pack. I did this on my hybrid Grubbe and the difference was dramatic. The controller I use is a multi voltage (inexpensive $30.) so you can use 36v. or 48v. lithium pack. It's a 30 amp controller and quite an upgrade to the 10 amp controller that came with the motor kit and upped the 360 watts output of the 36v. kit to 1440 watts with the 48v. battery and the 30 amp controller. In hp approximation 1/2 hp to 2 hp output gain. 750 watts equals one horsepower estimation which is the commonly used but not entirely representative calculation. Yes the 48v. lithium is a little more costly, but not a bunch.

Rick C.

 

[Forbidden Tuna]

I do actually have a second controller that is dual voltage with a higher amp rating. I'm just waiting on my battery to arrive from my friend. The size of the battery kind of dictates what engine I'll be going with. Battery will be mounted up front in between the cranks. If the battery takes up too much space I might have to just use a China Girl 66cc or a YD100 engine.

 

[Forbidden Tuna]

I'll be keeping it at 36v for this go round mostly because of North Carolina laws. We have a pretty strict 20mph limit on ebikes, and as long as we abide by that there's no paperwork required and you can ride on the sidewalk with pedestrians having the right of way. The gas engine will be there if I don't see police around and need a speed boost, or if my battery goes kaput.

 

[indian22]

I hear you Tuna & respect your reasoning. The legal aspects of riding vary greatly not just state to state but locally. I primarily go with what is acceptable to local law enforcement, even though it means staying off state highways for the most part on several of my bikes. Riding high powered bikes requires a great deal of rider moderation or traffic tickets will ensue. They are great fun however even for an Old Guy!

Riding safe & having fun are not mutually exclusive concepts...

Rick C.

 

[Forbidden Tuna]

Well I flew too high and into the sun. Got to enjoy a Predator 212 on a bike for the first time, until two of the bolts on the disc brake got ripped out. Luckily nothing too serious happened but I know when to quit while I'm still uninjured. Here's some pics of that progress. I really should have known better with the hub being made of chinese aluminum but I'll chalk it up to a learning experience.

At least I got to ride it up and down my driveway a couple times. This bike will just be a normal boring street legal eBike I guess. 212 will go on another project, probably with one of those moped hubs from MBRebel. Maybe a 29"er and try to emulate the old Triumph shape.

 

[PeteMcP]

Shame this build ended prematurely the way it did, Tuna.
I'm studying the last pic and struggling to figure out what I'm looking at. Are those the ripped holes you're talking about to the left of the glinting sprocket teeth? Was under the impression you were only running a disk brake up front on the Monarch forks. Hadn't glimpsed a rear brake in any other of your pics. Enquiring mind needs to know....

 

[Forbidden Tuna]

I was running a sprocket in the disc brake holes on the electric hub. Two of the bolts got ripped out from the torque and in that photo some are pulled out partially.

 

[indian22]

Looks like the rear rotor holes were used on the hub motor to attach the motor drive sprocket to the 212. If so it's an ill conceived design though it's done on occasion with an after market adapter to connect a low power gas engine to a standard rear hub with rotor mounts.

I'm not a fan of using the hybrid concept to drive the rear wheel with both motors. Driving front hub & rear hub has many advantages in design and practical application. Just because something is possible doesn't mean it's actually an effective solution.

Rick C.

 

[Forbidden Tuna]

I had attempted to fit a China Girl on it but just couldn't get a proper alignment.
Thought about another 79cc Predator but they're anemic unless geared to 15:1. I'm almost glad I'm reduced to just the electric hub because now the bike will be less temperamental and lighter weight. Also won't be harassed by police since it's totally street legal per North Carolina law.
I'll probably end up with a rim brake adapter on the rear and go for a disc in the front. Been using yabba dabba doo brakes for now while going at leisurely speeds.

 

[PeteMcP]

Thanks for the clarification.
Would still have liked to see you persevere with the stretched hybrid concept featuring an e-hub up front combined with predi rear drive.
Understand your reasons re NC legality though.

 

[Forbidden Tuna]

I will probably rehash this idea with a different frame in the near future. Something akin to Indians style but stretched out so everything is in the frame. Maybe a sixthreezero in the barrel. I think this Micargi frame uses too thin of tubing for the frame because I've already made a dent or two in the bottom tube from the plate adapters and the china girl clamps.

 

[indian22]

Tuna I like the look of the Micargi frame. Though I've had no first hand experience with them. Many off the rack bicycle frames are not good candidates however for motors generating more than a very few hp & low torque unless one baby's them in daily operation and ride smooth streets. I'd think not many would find this to be much fun. Thin wall tube is just one problem for motorizing, but saving weight on a straight pedal bike is a big deal& so I can't blame the manufacturer for saving weight and keeping costs down at the same time. The Felt frame motorizes well, quite strong and pricey. There are others, but beware of inexpensive knockoffs of real Felt frames, and others. The electric hub on your Micargi however should be a sweet ride that looks good getting you there...dependably and safely. These are desirable bike traits.

I can see you really getting into this hobby and building cool bikes along the way. Keep it up!

Rick C.