Harbor Freight Greyhound 79cc engine

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healingnations

New Member
Jan 5, 2011
10
0
0
Florida
2 Speed Trans and More

Cyclonetics 2Matic Transmission - http://www.cyclonetics.com/2maticblog.html

Browning Automatic Bicycle Transmission (2 speed). Not sure it's even in production, but worth a look, out of Germany - http://www2.bsn.de/Cycling/articles/browning.html

Check this guys 6.5 hp motorized-bicycle. 42.8 mph, he said scared to go faster! Awesome fabrication and mount! - http://www.youtube.com/watch?v=Nw7M78b52Jc&feature=related

Here's absolutely insane 160cc setup - http://www.youtube.com/watch?v=eQd_PwJo7q0&feature=related
 

healingnations

New Member
Jan 5, 2011
10
0
0
Florida
Shifter Hubs 3+ Speeds

A great thread going on here. Not sure why the big mystery over transmission/gear-shifter development for motorized-bicycles. Why not just move the shifting to the rear wheel? Maybe I'm wrong here, but Internal Shifter Gear Hubs for bikes have been around since the 1800s. Forget those crappy derailleurs or all this big investment on new transmission development. Now days they have internal hubs from 3 speeds up to 14. To keep it efficient a 3-speed hub would probably be more than enough gears.

The hubs can get pricey, but the ultimate in gear ratio selection. I would just make the rear sprocket less teeth (maybe 20-30t) instead of the 48t mentioned earlier, then everybody could take advantage of the gear ratios, obviously some trial and error would be needed for each motor and application, but a 5-speed hub would be fairly inexpensive and I think more than enough gearing options. I like the left handed (throttle like) hub shifters, easy to shift up and down with.

Plenty of manufacturers to choose from (hubs and shifters). Just watch those prices!!

Sturmey-Archer
SRAM
Shimano
Rohloff 14-speed (gears 12,13,14 on this hub are actually overdrive ratios!!)


I already bought a 6.5hp (196cc) 4 stroke (8.1ft/lbs @ 2500rpm) from Harbor Freight today ($100). I'm going to try a multi-speed rear hub. Already saw on YouTube a guy using this exact engine, fit in the frame no problem. Then I saw another guy on Youtube using an multi-speed rear hub with a 66cc engine, 40mph!


All the links for what's mentioned are below

http://upload.wikimedia.org/wikipedia/commons/b/bb/Speed1c.png
Hub gear - Wikipedia, the free encyclopedia
Sturmey Archer
Internal Gear Hubs | SRAM
Nexus
Rohloff AG - Sprocket ratios
YouTube - Home-Built 6.5hp Motorized Bicycle
YouTube - OilyPablo's Channel
 

healingnations

New Member
Jan 5, 2011
10
0
0
Florida
Transmission made Easy

Here you go guys. A very effective and simple multi-gear transmission, using an internal rear hub. Another member (camlifter) had pics of it on his bike. Brilliant in its simplicity. So the basics are:

1. Centrifugal Clutch goes to Jack Shaft
2. Jack Shaft goes to Internal Hub (acting as transmission, from 3 to 14 speeds)
3. Internal Hub goes to Rear Tire Sprocket

That's it. Very nice, very simple.


See attached pics.
 

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Dan

Staff
May 25, 2008
12,765
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Moosylvania
Suweet build Healing! Really looks great.

A very minor thing, I can't find it and may now be a moot point but up until a few yrs ago, (last time I read it in the Fed CGS, guide for state laws) it was stated that the transmission was to be maximum 2 speed and automatic. Not that it would matter and each state would vary. Here in CT they can now be any thing up to 5brake HP and any transmission is fine. Covered by the same local laws pertaining to bicycles, scooters and mopeds. Called "Motor driven cycles" The really confusing part is you can still find CT. "CGS 14-286" on the internet which states the old 50cc, 30 MPH laws. LOL, you would not believe how many folks I talk to who tell me I am wrong even after showing them the DMV hand book on the matter. Local cops (God bless em) just smile, wave or look away.

DMV: Important Information About Motorcycles, Motor Driven Cycles, Motor Scooters, Mopeds and Three-Wheeled Vehicles

Motor Driven Cycles: If you have a motor scooter, moped or motorbike having a motor that produces 5 brake horsepower or less (or 3.7 kW or less) and a seat height of at least 26 inches, you may operate it on the roadway without registering it. However, you must have a valid motor vehicle operator’s license to operate it, and you may not operate it on any sidewalk, limited access highway or turnpike. If the maximum speed of your cycle is less than the speed limit of the road that you are on, you must operate in the right hand lane available for traffic or upon a usable shoulder on the right side of the road unless you are making a left turn. As of October 1, 2008, these vehicles are referred to as “motor driven cycles.”

But again, I can not find the fed thing on it and think you have just made it a whole lot easier on us all! I know you just completely changed a build I was working on.

Is that a "suicide shifter"? Really cool looking build. Also, great tank, DIY?

Really important, we should all check our local laws periodically. I was all over the internet with the old local law. It changed and I had no idea. Also, even well meaning (or trying to sell ya some thing) folks may give you bad information.

(LOL, sounded a lil "preachie" there didn't I?)
 
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Hi Dan,

I don't think following the rules about legal drive systems are important when your power plant is rated at 6.5 HP to start with.

The majority of moped, motorbike, and motor assisted bicycles laws require AUTOMATIC drives [no manual shifting], under 50 CCs, and less than 2 HP but who bothers with the rules?

I am sure if enough people break the existing rules it will certainly be easier to have them changed in our favor [NOT].


You are lucky that your state has the 5 HP limit, and as a youth in Ohio the rules were also 5 brake HP [not now].

Have fun,
 

healingnations

New Member
Jan 5, 2011
10
0
0
Florida
Harbor Freight 196cc (6.5hp) w/tranny

Hi Dan,

The build isn't mine, it's a member's named camlifter. I'm a total newbie and just gathering all the info I can before starting my build. I just purchased the Harbor Freight 6.5hp 4 stroke the other day - $100. Quenton is absolutely right about exceeding local laws, so clearly a judicial throttle is going to be needed, but it's nice to know you got it when you need it. I will say though, I detect a fundamental change already happening in America regarding transportation. Camlifter did a little fabrication work (welding), but small 120vac welders are dirt cheap now days, and with a little welding practice his build should be replicate-able. I drive a 1993 GEO Metro XFI, get about 45mpg city, but looking to upgrade to a 2000 Honda Insight, average mpg is 63!! But I digress, the 196cc engine with a 5 speed internal hub, and proper sprocket ratios to keep the engine rpm low but still maintaining enough torque is the goal here. I think 85+ mpg is possible, maybe even better. I'm more interested in economy mixed with a little fun occasionally. I'm one of those hyper-miler guys!! In my thinking, we take the 6.5 engine base mounting plate idea from the Youtube guy and mix it with Camlifter's internal hub tranny setup, and we get a speedy, torquey, yet fuel efficient motorized bike! Probably have to go through some sprocket ratio iterations before it all comes together, fuel economy wise, but I think it's do-able with a little patience. The Youtube guy mentions what frame he used. Anyway, now let's just see if I can find a big durable frame to start this project. Time to start my build's parts list (ugggh). Some more pics are attached.
 

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healingnations

New Member
Jan 5, 2011
10
0
0
Florida
Internal Hub Longevity

I forget to mention that Camlifter said he rode his build with the hub (3 speed i think) with no problems for a year. Albeit his engine was probably 2.5hp, so easier on parts. I think he sold or traded it with it still working fine.
 

healingnations

New Member
Jan 5, 2011
10
0
0
Florida
196cc build

I just started trimming the fat off the 196cc harbor freight 4 stroke. Interestingly enough it has a Lifan sticker on the bottom, so it's not a harbor freight exclusive like they advertised. For $100 they can hype the advertisement all they want! I dis-engaged the rpm limiter by removing the spring to the carb and just wired it stationary so it wouldn't flop around. It's really just a centrifugal expansion mechanism that's connected to the main throttle blade on the carburetor via spring. Put in some oil and gas, two pulls later, she started right up. It'll turn 3800-4000rpm without damage, but I won't go any higher for longevity sake. It's capable of 4500+, but not worth the risk! I'll install an rpm gauge to keep things in check. Electronic RPM control is easy to do too, but for a $100 engine that's just overkill. I removed the gas tank and temporarily attached 4 feet of fuel line for shop and test. Still lots of work to do, but it's a start. Pics attached!!
 

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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
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northeastern Minnesota
I'm curious how much bigger this is than the 2.5 Greyhound which must also be Lifan. I have the 79cc mounted in a 51 cantilever framed Schwinn and it is snug in the frame and feels like I'm riding a motor it is so wide. My right calf rests against the engine as I ride. Is yours going in frame? On what kind of bike?
SB
 

healingnations

New Member
Jan 5, 2011
10
0
0
Florida
196cc build

Hi Silver,

The bottom tube on the bike frame will need a little modification, but nothing a cut-off blade and arch-welder can't handle. The basic idea has already been done by another guy on youtube. The difference with my build is I'll be using an internal hub for shifting, similar to camlifter's setup. Take a look at the pic and video attached. The engine mounting plate is much lower in the frame because of the modified lower tube. Hopefully the hub can handle the additional torque. If not, it's back to fine tuning the sprocket ratios and a more direct drive approach.

YouTube - Home-Built 6.5hp Motorized Bicycle
 

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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Re: 196cc build

Hi Silver,

The bottom tube on the bike frame will need a little modification, but nothing a cut-off blade and arch-welder can't handle. The basic idea has already been done by another guy on youtube. The difference with my build is I'll be using an internal hub for shifting, similar to camlifter's setup. Take a look at the pic and video attached. The engine mounting plate is much lower in the frame because of the modified lower tube. Hopefully the hub can handle the additional torque. If not, it's back to fine tuning the sprocket ratios and a more direct drive approach.

YouTube - Home-Built 6.5hp Motorized Bicycle
Interesting setup. That's a whole lot of motor there. I'd suggest starting your own build thread on this as it deserves a thread of it's own. Lots of photos, please. Good luck to you and stay safe.
SB