How to have 2nd freewheel on my bike

[nobtiba]

Hi, thanks for the pictures of your solution! Here is a photo of my bicycle:

I need to be able to use both the rear and front seats, so the positioning of the engine is quite important as I need to accommodate two children.
In @Sidewinder Jerry 's post, I'm unsure about the purpose of the following statement: "run a 7-speed 34-13 freewheel in the rear once you've installed a rear derailleur and hanger." Is it solely to enable speed selection? As long as the motor assists in achieving a normal biking speed, that should suffice for me. In your bicycle design, it's not very clear to me how the motor will independently move the middle part from the pedal.

When attempting to comprehend some of the terms in your post, I came across a YouTube video that suggested the shift kit may not be a good idea:
View: https://www.youtube.com/watch?v=qIAycuNwBag

 

[DAMIEN1307]

I need to be able to use both the rear and front seats, so the positioning of the engine is quite important as I need to accommodate two children.

Are you seriously going to have two children with you on this bike all at the same time???

 

[Gordy]

Hi, thanks for the pictures of your solution! Here is a photo of my bicycle:

View attachment 218539
I need to be able to use both the rear and front seats, so the positioning of the engine is quite important as I need to accommodate two children.
In @Sidewinder Jerry 's post, I'm unsure about the purpose of the following statement: "run a 7-speed 34-13 freewheel in the rear once you've installed a rear derailleur and hanger." Is it solely to enable speed selection? As long as the motor assists in achieving a normal biking speed, that should suffice for me. In your bicycle design, it's not very clear to me how the motor will independently move the middle part from the pedal.

When attempting to comprehend some of the terms in your post, I came across a YouTube video that suggested the shift kit may not be a good idea:
View: https://www.youtube.com/watch?v=qIAycuNwBag

That shift kit is a front freewheel, which will keep the pedals from moving while the drive chain is, but still allowing pedal assist. If you could get a front freewheel with a dual chainring setup you could run the motor on the front chainring to power the rear, and leave your rear setup alone

 

[Sidewinder Jerry]

The safer option would be to have a pull behind trailer for your children.

I'm 250 lbs and live in the mountains. A gas engine can have rpm between 3600~8000+ rpm. In order for an engine to propel the bike the rear wheel has to be spinning at a much lower rpm than the engine. This is known as a reduction drive system.

For example: Even with one of the lower 3600 rpm engines to do around 23 mph on 26 inch wheels with just 2 sprockets you would need a 10t on the engine and a 120t sprocket on the rear wheel. This may still not be a low enough reduction if you encounter a steep hill.

 

[nobtiba]

Are you seriously going to have two children with you on this bike all at the same time???

The total weight is estimated to be around 260-280 lbs.

 

[nobtiba]

That shift kit is a front freewheel, which will keep the pedals from moving while the drive chain is, but still allowing pedal assist. If you could get a front freewheel with a dual chainring setup you could run the motor on the front chainring to power the rear, and leave your rear setup alone

Since I am new to this and have tried multiple times without success, I need more details about the design and the items to purchase in order to make it work.

 

[Gordy]

Since I am new to this and have tried multiple times without success, I need more details about the design and the items to purchase in order to make it work.

When I get home today I'll take a few pictures of the shift kit I have and send them to you with a more detailed description of how they work. You would only need the front freewheeling chainring to build this setup you have, nit the whole kit.

 

[DAMIEN1307]

The total weight is estimated to be around 260-280 lbs.

Weight was not my initial concern, SAFETY is my concern.

In most countries, it is totally illegal to carry any passengers on a bicycle that is not expressly made for that purpose, (such as a tandem bicycle also known as a "bicycle built for two"), for obvious reasons.

Adding a motor to the bike now adds a further dimension to this scenario.

It is just plain dangerous as just one unforseen accident can cause serious injury or even death not only to you but the children as well.

 

[Urban Fatbiker]

Weight was not my initial concern, SAFETY is my concern.

In most countries, it is totally illegal to carry any passengers on a bicycle that is not expressly made for that purpose, (such as a tandem bicycle also known as a "bicycle built for two"), for obvious reasons.

Adding a motor to the bike now adds a further dimension to this scenario.

It is just plain dangerous as just one unforseen accident can cause serious injury or even death not only to you but the children as well.

Yes with a bullet! While a police officer may ignore a ‘potential’ violation based on engine cc or even shift kit, cause it looks legal from a distance, they won’t ignore an adult with two kids on a motorized bike.
You’ll lose that bike.

 

[DAMIEN1307]

Yes with a bullet! While a police officer may ignore a ‘potential’ violation based on engine cc or even shift kit, cause it looks legal from a distance, they won’t ignore an adult with two kids on a motorized bike.
You’ll lose that bike.

He is in Singapore so I have no idea how the authorities may look at this over there...Remember though that Singapore still uses "caning" as a form of corporal punishment...I am sure that would be quite a deterrent to would-be law breakers...lol.

Caning in Singapore - Wikipedia

en.wikipedia.org