My Motoped

as far as the ICE motors for motopeds..
i dont blame anyone for wanting gas,
especially if needed for range or to reduce build costs vs batts..

if you want to pedal then i would recommend the semi-auto 125cc
semi auto there will be no clutch lever on the bars so room for hand brakes..
w/ full auto it would shift very slow
but semi auto just ease off the throttle, hit the shift lever & go..
a higher power build would be manual transmission so clutch lever would replace brake lever on bars & rear foot brake lever would need pegs instead of pedals..

Pirate cycles who has built probably more motopeds than anyone..
recommends the 1down, 3 up transmission (if you can find it)
so that you can more easily skip through the low gears when/by pedaling..
maybe talk to them before you buy..
(the motors you listed are semi-auto but the have 4up trans..)

reference:
http://motopeds.com/forum#bublaa-/topic/53548f388a292e3d61722481/post/53603577b6ccefcf5557c853

good luck..


kfong said:
Been trying to pick out a gas motor. So many choices, there is even an oil cooled 150cc that looks promising. I'm trying to be practical on the choice and not go crazy with power. My main objective is a low profile setup that I can ride around town with and still have fun in the trails. I'm pretty sure it will see mostly trail use, but you still have to cross roads, sometimes long stretches. I think 45mph is the fastest I really care to go just to be able to keep up with traffic, and only 35 mph or less in the trails. I'm currently thinking 125cc might be a good power choice, but have no idea really how that would perform or feel.


After going through the listings, I'm down to these two choices. Anyone have any experience in this area?

LIFAN 125CC Motor Engine w/ Dress Up Kit XR50 CRF50 XR 50 70 CRF70 Z50 CT H SET $450
http://www.ebay.com/itm/LIFAN-125CC-Motor-Engine-w-Dress-Up-Kit-XR50-CRF50-XR-50-70-CRF70-Z50-CT-H-SET-/161053787561?pt=Motorcycles_Parts_Accessories&hash=item257f8dc5a9&vxp=mtr

125CC LIFAN COMPLETE ENGINE MOTOR FOR HONDA XR CRF 50 70 CT70 ST70 XL70 $340
http://www.ebay.com/itm/125CC-LIFAN-COMPLETE-ENGINE-MOTOR-FOR-HONDA-XR-CRF-50-70-CT70-ST70-XL70-/181391881401?pt=Motorcycles_Parts_Accessories&hash=item2a3bcc74b9&vxp=mtr
Click to expand...
 
kfong said:
Both bikes would make a good candidate for that motor. Once I have the motor in my hands, I will let that decide for me. The Motoped is one level up in weight compared to the Versus, and I thought that was a heavy bike. This one really is more of a moped than a bike, or even closer to a motocross, once the moped tires get installed. What's the expected watts or HP of the big block? We are moving away from ebike territory with this build and into a small motorcycle.
Click to expand...

I'm actually really excited about your Versus as well. That's also going to make a great e-bike. My problem is that I'm a zealot. I want to electrify everything.

It's pretty much unavoidable that high powered pedal hybrids will start becoming light motorcycles. My state of Oregon is pretty open minded about registering weird-azz home built vehicles (you can even drive full on race vehicles on public streets under certain circumstances in order to get to the race track). I'm going to try going legit with the state and see if I can register a human-electric hybrid motorcycle here. If you read the legal definition of "moped" the big block will exceed that if let off of it's leash. Most states say 20 mph tops for power assisted bicycle and around 30 for a moped. Yawn.

The armature magnets and stators in the big block are almost exactly twice as wide as the small block. It weighs very nearly twice as much at 11 lbs vs. 6 lbs for the small block. The manufacturer rates it at 1100 watts vs. 500 watts for the small block. Since the small block is being run regularly at 4 kW I'm expecting 6-8 kW for it's big brother.

efMX Trials Electric Freeride said:
(im guessing you want larger cogs on the jackshaft for motor reduction..)
Click to expand...

There will need to be a primary reduction stage before going to the jackshaft. The gassers that Vince is showing have their primary drives internally. A two stage would do it for the relatively low rpm big block up to around 48V.
 
Thanks efMX

I will see if those shift combinations are available. Glad to know I'm on the right track on the 125cc. The two choices I posted, one was the best value in my limited searching and the other seemed to have the best performance to $ ratio. Going gas is a very quick conversion. Going electric will take some fabrication, unfortunately summer is here and I'm only able to do things that can be done quickly. Once winter is back, I can devote more time on builds. Riding the trails is why I build these things in the first place. I can only peck away at the builds now. Way too many things on my plate and my interests sadly lack focus.

I will likely go with the value option for now, and see how I like having a stink bike over time. Maybe the big block CNG motor once next to the bike will get me motivated. Planning for that second stage on the Motoped will take some designing. For the Versus, the design is mostly done. Just need the physical motor so I can start mounting it. Things should get interesting since we just converted our 7x12 lathe into a CNC.


Some of my notes for those going electric.

CNG and Versus

The unloaded Kv of the stock GNG motor is 67...

36V X 67 = 2412 RPM
48V X 67 = 3216 RPM
72V X 67 = 4824 RPM

11" battery bay length

2.248-2.669 bottom tube diam.

6.25 before first water post mount

1.39 seat tube
1.587 top tube

Bicycle sprocket diameters:

____inches__mm
40T = 6.4___163
42T = 6.7___170
44T = 7.0___178
46T = 7.4___188
48T = 7.7___196
50T = 8.0___204
52T = 8.3___211
54T = 8.6___219
56T = 8.9___226
58T = 9.3___237
60T = 9.6___244

Bicycle gears
Cog Teeth Radius Inches Cog Teeth Radius Inches
10 0.809027886318775 33 2.63009311340335
11 0.887379767661787 34 2.70955591216871
12 0.965941669640332 35 2.78902541710941
13 1.04466364585876 36 2.86850106731321
14 1.1235104986384 37 2.94798236277534
15 1.2024566882985 38 3.02746885634353
16 1.28148322154136 39 3.1069601469094
17 1.36057567355722 40 3.18645587362662
18 1.43972288832893 41 3.26595571097952
19 1.518916099869 42 3.34545936455968
20 1.59814832314133 43 3.42496656743452
21 1.67741392261326 44 3.50447707701329
22 1.75670830068737 45 3.58399067233274
23 1.83602766880394 46 3.6635071516982
24 1.91536887666401 47 3.7430263306270
25 1.99472928302824 48 3.82254804004996
26 2.0741066567262 49 3.90207212473375
27 2.15349909993283 50 3.9815984418933
28 2.23290498807221 51 4.06112685996837
29 2.31232292228593 52 4.14065725754055
30 2.39175169150125 53 4.22018952237484
31 2.47119024190823 54 4.2997235505667
32 2.55063765220899 55 4.37925924578353
 
I've been searching out motors with different shift combinations. I found one with 4 down, but it's 110cc. I think this is preferable than 4 up or 1 down 3 up. I have not been able to find a 125cc with this combination. I will be giving up some power, but the shifting seems better.
 
Are you going for footpegs or a bicycle crank on your Motoped? I've been trying to visualize foot shifting a motorcycle trans from a bicycle crank and it seems awfully awkward to me. What's the plan, man?
 
Mike, I want to keep the pedals. That's the whole point of the motoped. As mentioned earlier in this thread, shifting is not an issue. I'm just being particular on how I prefer to shift. 4 down seems best to me. As long as I'm not speeding and keep low key, I should be able to ride it around town. It will be considered a moped by the cops, unless they check the motor displacement. I don't plan to give them cause to check it.

Dual conversion is also planned since two bolts are used for the mounts. This makes for an easy gas or electric conversion.

Use the electrics around town and the gas for up north where distances make it impractical. Been giving this a lot of thought lately. Mechanical throttle can be setup for both setups since it's easy to add a hall sensor and just measure throttle displacement. The exhaust is mounted just at the motor and rear rack, so removal is rather easy. I plan to keep the electric motor and assembly as a unit. Switching between the two should be rather quick, only 2 bolts. Battery mounting will take some creative thinking, but I already have ideas on that front using the a123s 20 ahr cells. I'm rethinking the Versus power plant, the big block might be better suited to this frame. Will know once I have it in my hands, or go even bigger. I will be putting moped tires on this setup and looking for some serious brakes. It will be more like a light motorcycle/motocross.
 
very interesting build plans!

as per shifting..
the semi auto motors have a left foot shift lever
but no clutch lever on the bars..
its not that hard to shift once you learn how..
but you wont be pedaling much while shifting or under motor power..
just a small bit of back/fwd pedaling while your left foot is on the shift lever..
you also need the right length cranks, shift lever (& feet;) for proper clearance..
when you are pedaling, such as under under low speed..
then your foot should clear and pass by the shift lever..
when you want to shift then move your foot forward a bit to contact the lever
and back or fwd pedal a bit to shift up/down..
you get used to it..

as per the ice transmission..
of course everyone will have their own preferences..
and it may take trying different setups to see what you like best once riding..
but.. the reason some prefer the 1dwn/3up is so that first gear can be skipped over when under way
since first gear is only needed for getting going.. but since you have pedals then first gear wont be needed much.. therefore its preferred by some not to have to shift through first to get to second..
just shift from neutral to second skipping first..

keep us posted on what you get & how it works out for you..

as for the hybrid or dual build..
ive been dreaming of a tri-brid using the motoped chassis..
what if the electronics were small enough to remain on the bike..
& the ice could be used to charge the batts when under power or deceleration if desired
(would increase fuel consumption of course)..
and the motor could serve as motor & generator
w electric power for a stealth power mode..

will be following your progress..


kfong said:
Mike, I want to keep the pedals. That's the whole point of the motoped. As mentioned earlier in this thread, shifting is not an issue. I'm just being particular on how I prefer to shift. 4 down seems best to me. As long as I'm not speeding and keep low key, I should be able to ride it around town. It will be considered a moped by the cops, unless they check the motor displacement. I don't plan to give them cause to check it.

Dual conversion is also planned since two bolts are used for the mounts. This makes for an easy gas or electric conversion.

Use the electrics around town and the gas for up north where distances make it impractical. Been giving this a lot of thought lately. Mechanical throttle can be setup for both setups since it's easy to add a hall sensor and just measure throttle displacement. The exhaust is mounted just at the motor and rear rack, so removal is rather easy. I plan to keep the electric motor and assembly as a unit. Switching between the two should be rather quick, only 2 bolts. Battery mounting will take some creative thinking, but I already have ideas on that front using the a123s 20 ahr cells. I'm rethinking the Versus power plant, the big block might be better suited to this frame. Will know once I have it in my hands, or go even bigger. I will be putting moped tires on this setup and looking for some serious brakes. It will be more like a light motorcycle/motocross.
Click to expand...
 
I've thought a lot about adapting a motorcycle sequential shift transmission to a powerful e-bike. It seems that a solenoid should be a good solution for moving the shift lever up and down through the gears. That way shifting could be done with a thumb switch up on the handlebars.

I suppose you'd get used to the pedal dance in order to foot shift but I'd rather not if I had a choice. Putting pedals on a bike and not being able to use them because you're busy shifting is less than optimal.

I had a Honda Trail 70 with an automatic clutch and 3 speed manual when I was a kid. Very similar to the motor shown on the factory bikes.
 
thats a great idea for the shift lever..
(in fact its been done b4, not by me of course)

or a full auto motor of course wouldnt need a shift lever
but it would shift slow.. always compromises..
also remember the motoped is single speed pedal input..
so pedaling at speed was never much of an option
unless of course you build a multispeed pedal trans in there..


LightningRods said:
I've thought a lot about adapting a motorcycle sequential shift transmission to a powerful e-bike. It seems that a solenoid should be a good solution for moving the shift lever up and down through the gears. That way shifting could be done with a thumb switch up on the handlebars.

I suppose you'd get used to the pedal dance in order to foot shift but I'd rather not if I had a choice. Putting pedals on a bike and not being able to use them because you're busy shifting is less than optimal.

I had a Honda Trail 70 with an automatic clutch and 3 speed manual when I was a kid. Very similar to the motor shown on the factory bikes.
Click to expand...
 
eFMX, thanks for clearing that up. I had assumed I had to go through the gears. I didn't know I could jump to second. Mike, a solenoid setup is a very cool way to do it. It has me thinking! Will know once I get the motor how much shift pressure will be needed. Two solenoids on a rocker setup would be simple to design.
 
kfong said:
eFMX, thanks for clearing that up. I had assumed I had to go through the gears. I didn't know I could jump to second. Mike, a solenoid setup is a very cool way to do it. It has me thinking! Will know once I get the motor how much shift pressure will be needed. Two solenoids on a rocker setup would be simple to design.
Click to expand...

You are the man to design it! I'll be wanting one for my own m/c transmissioned bike. I'd also like a motor power cutout when the solenoid engages to shift gears, please. Just hold it WFO and hit the shift toggle. :D
 
heres some auto shift kit on market for possible parts, inspiration, etc

http://www.disabledmotorcyclerider.com
newfrontpgpic2.jpg


http://www.quickshifters.com
updownandhand.gif


http://www.mpsracing.com/products/MPS/as01.asp



LightningRods said:
kfong said:
eFMX, thanks for clearing that up. I had assumed I had to go through the gears. I didn't know I could jump to second. Mike, a solenoid setup is a very cool way to do it. It has me thinking! Will know once I get the motor how much shift pressure will be needed. Two solenoids on a rocker setup would be simple to design.
Click to expand...

You are the man to design it! I'll be wanting one for my own m/c transmissioned bike. I'd also like a motor power cutout when the solenoid engages to shift gears, please. Just hold it WFO and hit the shift toggle. :D
Click to expand...
 
Cool, one solinoid, push pull with off being center. That's as simple as it gets, easy to wind one up using magnet wire and a drill. Customize a small unit tailored to these motors, so it's not anymore bigger than it needs. Circuitry to activate them would be simple, hell I could get fancy and auto shift based on speed, use a switch for setting profile. Performance mode, cruise mode, ect. Even allow programmed shift points. I see another project in the makings.

Is it good to shift under power, or do we need to throttle down each time. Need to figure that part out if we want this auto electronic shift. Temporary shutdown of the ignition coil comes to mind?
 
kfong said:
Is it good to shift under power, or do we need to throttle down each time. Need to figure that part out if we want this auto electronic shift. Temporary shutdown of the ignition coil comes to mind?
Click to expand...

It's not good to shift under power. We used to do it racing motocross but it beats the hell out of your equipment. On an electric install it's easy- you just cut the power. For gas it's better to cut air and fuel than ignition but for an event as brief as a shift it shouldn't matter. Like the solenoid motorcycle shifters (which I'd never seen) I'm sure someone is doing this already.

For electric motors it might be better to experiment with various levels of reduced power when shifting instead of a total shut off. We want to take the load off of the gears during the shift. The cogging of a dead motor might load the gears more than partial power.

Imagine a nice four speed constant mesh back where that jackshaft is. Both pedal and motor power go through it. That's exactly what I've been dreaming of for months.
 
Mike, seems like you could just marry the transmission of these cheap gas motors with a electric motor. You can find lots of them on locally, since you don't care if they run.
 
:arrow:
kfong said:
Yep, but until batteries progress. This stink bike will still out distance yours on a full tank. That and the cost are the only reasons that I'm going this route...


I had considered a123 for the Motoped, but riding up North with them still won't work out.
Click to expand...
How much range do you need?

What is the approximate price of the gas engine?
 
I can easily see myself going 100+ miles. Northern and Upper Michigan has extensive snowmobile tracks and wooded areas. Charging just isn't practical and the wait would be a hassle. Even considering bringing a tent on such ventures. GPS would be needed so I don't get lost. Gas engine I'm looking at is under $400. Seems like a fun way to explore the state.
 
You can't argue with the energy density of petroleum. This is actually a good breakdown of the way energy should be managed: electric for short range in town commuting, petrol for rural long distance runs. The automotive model in Oregon is Leafs and Priuses in the cities and diesel pickup trucks out in the country.

While you're looking for ICEs consider a used small displacement, high output motor from one of the big Japanese mfrs. I bet you could find an 80cc Japanese motor that is half the size and weight of the Chinese Honda 90 knockoffs that has higher output. Apologies if you've already discussed this option. That is the gas motor I'd want on the Motoped.
 
Mike, my main concern is the mounting. These Motopeds were designed for the old Honda style motors, easy to pick up on eBay for me. I'm not familiar with the motors you are talking of? Got any links.

We got posted on hackaday again, my brother did the conversion! Looking forward to making my first bike part on it.
http://hackaday.com/2014/06/06/lathe-cnc-upgrade-is-nothing-to-shake-a-turned-stick-at/#more-124007
 
Mike, that would take too much work to convert. Motopeds take horizontal engines, I have font and rear shocks coming. They were part of the purchase. The rest should be easy to find. I'm hoping to get this done quickly, since it's all plug and play. I can mess with the mods when I have more free time.
 
My upgraded front forks came in, I didn't know they were Marzocchi 888. Pleasant surprise. It was packed only in the factory box. Needed better padding since it blew though the box. The front face of the fork was banged up. Some paint chips resulted. The rest looks good, and the all important shock surface is intact. I'll post pics soon. Still waiting for the rear shock and rear hub from Motoped.

The steer tube is the standard 1 1/8", but measuring the Motoped ID, it's 1.9" roughly. This isn't a standard I'm familiar with. I was expecting to see 1 1/2"

From the kickstarter site,
"Frame The frame is hand tig welded out of certified chro-moly tubing. Head tube size is 1 1/2" mountain bike. All tank/seat/ body mounts are Honda crf50 style pitbike. Shock mount is 7/8" wide with 8mm(5/16") hole. Frame is powder coated metallic grey."

Not sure if they sent me the wrong headtube size?
 
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