Thats because most Florida drivers I've ever seen all seem to look like Clara Peller who can't see over the steering wheel and drive just as bad...lol...lol.
View: https://www.youtube.com/watch?v=idnwh6iDnXA
China doll vs dirt bike engine vs predator 212
- Thread starter Skullcmd
- Start date
View: https://www.youtube.com/watch?v=idnwh6iDnXA
I choose a 125cc because it's pretty common, nothing wrong with 50cc and one of the main benefits of most dirtbike engines (not that they all include it) is gear shifting, still would prefer a smaller displacement dirtbike engine than a predator with a cvt as I've tried both and there's better acceleration with the other. If a chinadoll had a shifter it would be way better, I know there's the jackshaft and even hubs with inbuilt gearshifting but hubs aren't meant to work on the left side and jackshaft comes with its downfalls, hubs are expensive and jackshaft i think looks ugly, smaller chain to work with the sprockets, and would only get gear shifting from mountain bikes (I've never used a jackshaft and haven't really looked into the details but I've looked at some videos of it and id suspect those would be issues, although I may be wrong on how it works) still a motor built with one would be way better.
cloakedvillain
Well-Known Member
do you have the bike you want to motorize or are you looking around still? Part of the reason the predators can be slow is the governor and low power to weight ratio. 3-4 hp is plenty for most steel bicycles. With a chicago schwinn or similar over built frame there's more fudge factor due to the fatigue strength of 1010 steel. You are looking at 40 lbs before the engine though!
Wheels are another thing, while quality hubs have the fudge factor for 30-35 mph beyond that you want moped wheels.
You'll want suspension. Jerry knows better than me on suspension seat posts and saddles. Suzuki k10 forks will fit on bikes built for 1 inch steerer tubes. Plenty of good and basic suntour xc options but hard to find forks that have the strength for confidently riding at speeds higher than 30-35mph.
Same story for tires, kevlar/commuter tires have good tread life, and you can get speed rated bicycle tires but even dirt cheap tires for 16 inch moto rims will be a safer choice at high speeds.
Bicycles and motorcycles share handle bar diameter so you can get mirror mounts meant more for minimalist motorcycle builds on your mountain bike. Heres an example https://www.ebay.com/itm/3876193025...jmq7wgurws&var=&widget_ver=artemis&media=COPY
You will want headlights, turn signals and brake lights. There are inertia based brake lights used on bicycles but its also easy to wire up your own harness for a motorized bike with a battery you keep charged. DOT lights on a homemade motorbike! Image that.
Braking is another thing to think about. Honda used rim brakes that looked like chunky V brakes for 60s 50cc bikes but it did not work well in the 125cc bracket. Too much heat, tire can get unwanted pressure increases, to the point of unseating in extreme cases. 203mm are the biggest mtb rotors I know of. 160mm are the most common though. Hydraulic brakes feel better than purely mechanical but the force is still ultimately limited by your hand. Right before locking up is the strongest possible braking.
I know of a a handful of ways to convert 3 speed hubs into two speed fixed gear hubs, which does let you keep your chain on the left. But I need to experiment to determine what method is the least tooling intensive for an individual to do. All work via locking the planet carrier to the hub shell.
Wheels are another thing, while quality hubs have the fudge factor for 30-35 mph beyond that you want moped wheels.
You'll want suspension. Jerry knows better than me on suspension seat posts and saddles. Suzuki k10 forks will fit on bikes built for 1 inch steerer tubes. Plenty of good and basic suntour xc options but hard to find forks that have the strength for confidently riding at speeds higher than 30-35mph.
Same story for tires, kevlar/commuter tires have good tread life, and you can get speed rated bicycle tires but even dirt cheap tires for 16 inch moto rims will be a safer choice at high speeds.
Bicycles and motorcycles share handle bar diameter so you can get mirror mounts meant more for minimalist motorcycle builds on your mountain bike. Heres an example https://www.ebay.com/itm/3876193025...jmq7wgurws&var=&widget_ver=artemis&media=COPY
You will want headlights, turn signals and brake lights. There are inertia based brake lights used on bicycles but its also easy to wire up your own harness for a motorized bike with a battery you keep charged. DOT lights on a homemade motorbike! Image that.
Braking is another thing to think about. Honda used rim brakes that looked like chunky V brakes for 60s 50cc bikes but it did not work well in the 125cc bracket. Too much heat, tire can get unwanted pressure increases, to the point of unseating in extreme cases. 203mm are the biggest mtb rotors I know of. 160mm are the most common though. Hydraulic brakes feel better than purely mechanical but the force is still ultimately limited by your hand. Right before locking up is the strongest possible braking.
I know of a a handful of ways to convert 3 speed hubs into two speed fixed gear hubs, which does let you keep your chain on the left. But I need to experiment to determine what method is the least tooling intensive for an individual to do. All work via locking the planet carrier to the hub shell.
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@cloakedvillain I've already mentioned but haven't clearly stated what I have, I have a 2020 style phatmoto and a yd100, I'd like to get a 125cc 4 stroke to put on later and as for personal toys i have a go kart fitted with a predator 212 with governor removed and a vm22 carb along with a mini dirtbike with the same 125cc 4 stroke. It's a crappy go kart vs a dirtbike but I simply think it's a little bit too much for my bike, if It can easily flip over my go kart I don't want that on my bicycle and it has a fundamental rpm limit without changing the valve springs.
I've also mentioned already that suntour forks are real good for this application but Kevlar tires would be a real good benefit, I have the all terrain phatmoto but the hubs are crap so I'll look into swapping both wheels with something better. Probably would've been cheaper if I started with just the frame and built up but everything was a gift and was meant to be used day one to get to places, just we got it used and it came with a 2 stroke which the diy mount broke soon after. Months later and we made a sturdier one, i think we have some hydralic brakes that was meant for a side by side but never used so maybe I'll use those or maybe steal it from a scrapped quad.
Unsure but it would be neat to see a converted geared hub to work on the other side. Mirrors and lights shouldn't be an issue, should be able to power a battery from the engine to power the electronics and there may be a lighting kit out there but otherwise I can wire something up, I have a lot of knowledge in software development so I may build myself a custom speedometer, tachometer, and temp sensor with a rasp which I do have a 3d printer but it's kind of broken ATM although I haven't done anything quite like a speedometer so it should be fun, I'd like to use something like android auto to perhaps get into Uber eats and have GPS so just a all in one device but I don't think I'll be able to do that without spending a year on it.
The biggest thing limiting me on doing anything is a lack of a welder, every diy project I've ever done was with a drill and some bolts with adhesives and parts, very annoying especially when I'm met with design decisions from 30 year old manufacturers that put a uncommonly used size chain meant for bicycles on a predator powered gokart with the smallest brake disc and front shocks ever with a rotted out floor, twisted frame, and twisted drive shaft. But hey I Made it work even if the fuel tank was destroyed and further destroyed the carb every time I put it away
or the Kevlar lined belts turn into string after a week. The Florida sun destroys everthing
I've also mentioned already that suntour forks are real good for this application but Kevlar tires would be a real good benefit, I have the all terrain phatmoto but the hubs are crap so I'll look into swapping both wheels with something better. Probably would've been cheaper if I started with just the frame and built up but everything was a gift and was meant to be used day one to get to places, just we got it used and it came with a 2 stroke which the diy mount broke soon after. Months later and we made a sturdier one, i think we have some hydralic brakes that was meant for a side by side but never used so maybe I'll use those or maybe steal it from a scrapped quad.
Unsure but it would be neat to see a converted geared hub to work on the other side. Mirrors and lights shouldn't be an issue, should be able to power a battery from the engine to power the electronics and there may be a lighting kit out there but otherwise I can wire something up, I have a lot of knowledge in software development so I may build myself a custom speedometer, tachometer, and temp sensor with a rasp which I do have a 3d printer but it's kind of broken ATM although I haven't done anything quite like a speedometer so it should be fun, I'd like to use something like android auto to perhaps get into Uber eats and have GPS so just a all in one device but I don't think I'll be able to do that without spending a year on it.
The biggest thing limiting me on doing anything is a lack of a welder, every diy project I've ever done was with a drill and some bolts with adhesives and parts, very annoying especially when I'm met with design decisions from 30 year old manufacturers that put a uncommonly used size chain meant for bicycles on a predator powered gokart with the smallest brake disc and front shocks ever with a rotted out floor, twisted frame, and twisted drive shaft. But hey I Made it work even if the fuel tank was destroyed and further destroyed the carb every time I put it away
or the Kevlar lined belts turn into string after a week. The Florida sun destroys everthing
cloakedvillain
Well-Known Member
125cc phatmoto
View: https://youtu.be/8wPjMnzfWEA?si=BaydjFvtOVKyhiI-
Funny drive train but a 212 shoe horned in.
View: https://youtu.be/WsGAVKeIFP0?si=mKuNAAIAhtftXPGa
View: https://youtu.be/8wPjMnzfWEA?si=BaydjFvtOVKyhiI-
Funny drive train but a 212 shoe horned in.
View: https://youtu.be/WsGAVKeIFP0?si=mKuNAAIAhtftXPGa
Sidewinder Jerry
Well-Known Member
Maybe I'm somehow not comprehending what @Skullcmd is saying. My understanding of this is you can put a China girl engine on a bicycle frame and then, for legal purposes, call it a micro-mobility device or call it a motorized scooter. It won't require the rider to have a driver's license, prove financial responsibility, and registration. You can also ride it on the sidewalks under engine power. You just have to go less than 30 mph.
Now let's go with some forum history. Before Florida DMV procedure RS-68, many riders tried to use the self-propelled vs pedal-assist argument but sadly came back stating they lost the argument in court. What I'm trying to prevent is any Florida riders reading this thread thinking they can get around RS-68. Some areas of Florida are very strict on enforcing their guidelines. The only Florida vehicles that will allow you to use a bicycle frame are electric bicycles and mopeds. Insurance and registration is much cheaper than being fined in court. Unless of course you're talking about SR-22 insurance.
Here is a site stating the differences between a gas-powered motorized scooter and a motorcycle. The state of Florida doesn't require motorcycle insurance but you have to fill out a form to prove financial responsibility if you choose not to have insurance.
shakedlaw.com
If you make a home made motorized scooter or motorcycle for street use, you must use this form
In order to make a custom-built motorized scooter or motorcycle frame, you have to take a course to get certification. Otherwise, you have to use a manufactured motorized scooter or a motorcycle frame. You could also buy a custom built frame from somebody who is a certified frame builder.
Now let's go with some forum history. Before Florida DMV procedure RS-68, many riders tried to use the self-propelled vs pedal-assist argument but sadly came back stating they lost the argument in court. What I'm trying to prevent is any Florida riders reading this thread thinking they can get around RS-68. Some areas of Florida are very strict on enforcing their guidelines. The only Florida vehicles that will allow you to use a bicycle frame are electric bicycles and mopeds. Insurance and registration is much cheaper than being fined in court. Unless of course you're talking about SR-22 insurance.
Here is a site stating the differences between a gas-powered motorized scooter and a motorcycle. The state of Florida doesn't require motorcycle insurance but you have to fill out a form to prove financial responsibility if you choose not to have insurance.
Laws on the Road: What’s the Smallest Street-Legal Motorcycle?
Several small, street-legal motorcycles are acceptable under Florida law. In case of an accident, a Miami motorcycle accident lawyer can help.
shakedlaw.com
If you make a home made motorized scooter or motorcycle for street use, you must use this form
In order to make a custom-built motorized scooter or motorcycle frame, you have to take a course to get certification. Otherwise, you have to use a manufactured motorized scooter or a motorcycle frame. You could also buy a custom built frame from somebody who is a certified frame builder.
Its up to 30 for a moped with pedals, thats typically a chinadoll with a 44 tooth sproket. Mopeds need registration aswell. My operating principle to call it a motorized scooter is to limit it to 20mph along with other modifications, anything that can go more than 30 is a motor scooter and considered a motorcycle which you need to have motorcycle endorsement (take a class), registration, and proof you can pay if you get into an accident (typically insurance otherwise id imagine youd need at least 10k in savings which is a requirement if you dont want insurance on a car.) Most engines dont meet the requirement of a moped anyways because its well above the 50cc requirement so typically all chinadoll engines dont meet the requirement for rs68 and are considered motorcycles. To register it as a motorcycle you need to get it inspected and fill out a builders affidavit and get title.
artinmotionllc.net
This is why im pushing to use it just as a motorized scooter, otherwise im forced to say its a very illegal motorcycle.
the 50cc or less requirment is in the rs68 form but heres a website saying it aswell
www.911bikerlaw.com
Florida Registration and Title for a Custom Motorcycle Assembled from Parts
This article describes the Florida Registration and Title process from Art In Motion LLC Custom Motorcycles perspective and experience. Refer to Florida State DHSMV for current regulations & forms.
This is why im pushing to use it just as a motorized scooter, otherwise im forced to say its a very illegal motorcycle.
the 50cc or less requirment is in the rs68 form but heres a website saying it aswell
Moped Laws in Florida
Mopeds are popular vehicles for city transportation, but before you hop on, learn about safety and road requirements for moped drivers in Central Florida.
yeah, i just have had a bad time with predator engines, have a pessure washer aswell and i just simply dont want to deal with it, also i like shifters as the cvt, whether its with a belt or friction between two plates, go bad very quickly. Maybe if i really cant spare the money ill stick on a predator or just for the funny but ill try to put on a dirtbike engine for now.
Sidewinder Jerry
Well-Known Member
Well now it sounds like we're a little more in agreement. Putting a China girl on a bicycle frame and staying under 20 mph may work fine in your area. However, doing this especially in the larger cities probably isn't going to work. As soon as the police hears that gas engine they're going to want to know where your rear tag is regardless of how fast you were going.Its up to 30 for a moped with pedals, thats typically a chinadoll with a 44 tooth sproket. Mopeds need registration aswell. My operating principle to call it a motorized scooter is to limit it to 20mph along with other modifications, anything that can go more than 30 is a motor scooter and considered a motorcycle which you need to have motorcycle endorsement (take a class), registration, and proof you can pay if you get into an accident (typically insurance otherwise id imagine youd need at least 10k in savings which is a requirement if you dont want insurance on a car.) Most engines dont meet the requirement of a moped anyways because its well above the 50cc requirement so typically all chinadoll engines dont meet the requirement for rs68 and are considered motorcycles. To register it as a motorcycle you need to get it inspected and fill out a builders affidavit and get title.
Florida Registration and Title for a Custom Motorcycle Assembled from Parts
This article describes the Florida Registration and Title process from Art In Motion LLC Custom Motorcycles perspective and experience. Refer to Florida State DHSMV for current regulations & forms.
This is why im pushing to use it just as a motorized scooter, otherwise im forced to say its a very illegal motorcycle.
the 50cc or less requirment is in the rs68 form but heres a website saying it aswell
Moped Laws in Florida
Mopeds are popular vehicles for city transportation, but before you hop on, learn about safety and road requirements for moped drivers in Central Florida.
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