My Road Trip Project

[WorkingOnWise]

I am building a motorized bike that will allow me to do long trips on the bike.
I will be starting with a yet-to-be-chosen mountain bike. The bike will have an aluminium frame, shimano deore ls or xt components, and disk brakes, likely Avid.
The bike will also have a freeradical, from www.xtracycle.com, installed, to allow for some serious cargo. The engine will be installed as low as I can get it, behind and below the seat.
I will build the drivetrain for the engine myself.
I intend on carrying myself, the bike, a trailer, my 60lb dog, plus 200lbs of cargo. I figure the total weight will be 500lbs.
My goal is to travel with this load at 30mph (no faster), with a little power on reserve to maintain speed up a hill.

My questions are:
1) What horsepower would I need?
2) Will a standard bike chain work as the drive chain for this engine?
3) Is there a freewheel sproket I can use that will handle the engine needed, and be compact enough to fit on a bike?

I know 500lbs is a lot for a bike. about 100 of it will be the dog, who will be in the trailer, towed behind me.

I know this is a srange project, but it is what we want to do. With that much weight, I don't know how much I'll be able to peddle, but as long the the engine runs, it won't matter.

Oh, the trips we want to take will be as long as 350 miles one way

Thanks
keith

 

[gone_fishin]

hiya...this was close enough to an introduction and it didn't exactly fit in the Q & A area, so...

anyways, it sounds like you've got your work cut out for you, and it also sounds like a lot of fun

i think you'll probably get your hp-to-weight/drive-train questions answered by someone who wanders by to say howdy...then check out "wild in the streets" for a few neat sprocket tweaks, jackshafts, gearing talk, etc...

when you're ready for the build, we'd love to see you start a project thread in "general" or i'd suggest "wild" because it does sound wild to me

welcome to MBc

 

[Alaskavan]

Hi Working. Welcome to MBc. There are several vendors who sell hubs and wheels set up for freewheel sprockets on both the right and left sides. That's a lot of weight to be hauling at 30. I'll be interested to see how you get 'er done.

 

[WorkingOnWise]

Lol... Yeah, that is a bunch of weight. It was a lot at 20! At almost 40, I wouldn't get 10 miles without a little gasoline assist for this meat motor!
The project looks good on paper!
I will definitely post s I go. Probly with more questions....
As long as I don't pretzel $800 of bike, my wife is game for whatever I bulid!
I didn't tell you guys the crazy part yet!

 

[Dockspa1]

Sounds like you need to go to a 6-8 HP 4-stroke with a torque-a-verter belt drive. I am no pro, but that is a lot of weight for a bicycle. Maybe a tricycle is a better choice, putting the weight on 3 wheels instead of 2?
Welcome
Doc

 

[Alaskavan]

As Augie said, you should start a thread in "General" or "Wild" to discuss your project. I'm sure there are a lot of members that have ideas and opinions (I know I do), and the ideas may get lost to others if they stay in "Introduction".

 

[bamabikeguy]

How old and agile is the dog??? Cuz HE might have to trail behind you occasionally !!

Good luck, should be do-able, bet a Tanaka 40 could do it, but not at 30, maybe 22-25.

 

[npk1977]

On flats, you'll be OK with low power, you'll just accelerate very slowly!

My setup is a 48cc from that's dax. My whole gig weighs something like 300#. I go uphill at like 18-20mph on a decent grade. That means you need more than DOUBLE the power of dax's 48cc.

good luck
n

 

[bamabikeguy]

On flats, you'll be OK with low power, you'll just accelerate very slowly!

My setup is a 48cc from that's dax. My whole gig weighs something like 300#. I go uphill at like 18-20mph on a decent grade. That means you need more than DOUBLE the power of dax's 48cc.

good luck
n

He's right, you need "takeoff torque".

Downhill/500 pounds? You might top 60, it will all average out.

The dog will LUV downhill.

 

[Dockspa1]

That My friends is why I suggested the larger 4 stroke. For low end power with torque-a-Verter for hills.
Where's that ace mechanical engineer that belongs to this forum?
With that kind of weight you almost have to go illegal in engine size for it to perform right.
Doc