How fast how much weight etc etc

GoldenMotor.com

the13bats

New Member
May 3, 2012
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Orlando
Okay...I realize my question could be painted with a broad brush but,
I see lots of motor-bike kits out there, most run what I call a "Weed" engine, I have used these engines in RC boats, cars etc.

I am curious, as I plan to add an engine to a 4 wheel bike, I do not want a speed demon, rather a cruise around the neighborhood type idea,
I am thinking because I am heavy and the bike is heavy I might just need to run like a 3-5 HP edger type 4 stroke engine, ( big, heavy )

However,
Like I said I'm curious, how much weight are some of you making move with the "weed" engines,

Tell me your CC's 2 or 4 stroke, your rigs full weight with you on it ( guesses are fine ) and then how fast will it move along...

Also, anyone messed with that side shaft engine Harbor tool sells for just over 100.00 ?

Many thanks!
Cheers,
P.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
I had a 23cc "weed" engine (Bike Bug). It moved me 200lbs., and a Next bike up to about 20mph or so with a friction drive. I would suggest something a bit larger for your application, like at least 35cc.

If you are talking about a "preditor" from harbor freight, then yes, dozens here have used it.

Probably a better bet than a "weed" engine.
 

jowens

New Member
Jul 25, 2011
128
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0
Webster Fl
Welcome fellow Central Floridian.......
Im one of the dozens who have built one of the Predator Harbor Frieght bikes. Mine is a 99cc put onto a Micargi Rover beach cruiser. It weighs in with me on it at about 240 lbs, Im guessing. With how I have the gearing on it at 9.6/1 with a Q-matic tranny, I have hit 42MPH at 5200 RPM. I rarely and I mean rarely push it that fast because I would like for my new build to last a little while. However I consistantly run it at 4500 RPM for an hour or 2 at a time without any struggle or worry. At 4500 RPM I run 36 MPH which is more than fine with me!http://http://motorbicycling.com/showthread.php?t=38434

Prior to this build I did start with a 66cc 2 smoke kit and probably worked all the kinks out of it, but got fed up with tweeking the build all the time and made the decision to go with the Predator motor and test my fabricating ability. Im very happy I did and will not go back to 2 stroke except to put the old motor on another bike and probably give it to someone.
 
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the13bats

New Member
May 3, 2012
24
0
1
Orlando
Thanks all...yes, the Predator 99 it sounds like a winner, what do you believe the HP rating to be?

So why do you need the Q-matic?

I have been building recumbents for over 20 years, my favorites are tadpole trikes, but I have been getting into the 4 wheel bikes,
I bought this one the other day that looks a lot like the old Briggs and stratton 5 wheeler,
the 5th drive wheel is like a trailer in back, it had an engine in the side, I want to do something like that seems the predator 99 would be a hot ticket,



I have to wonder how heavy the B&S design was, I am guessing the engine and drive parts would be more than the new predator 99,

My plan was to use the rear swing arm from a discarded mountain bike, it will give me a nice looking frame, and pivot,
But I planned to just use a clutch on the engine to a large sprocket on the side of the wheel, I know from my go kart and mini bike days that is good from take off to...??? well, faster than I want to go on this thing,

Which brings me back to why the extra Q-matic thing?


Welcome fellow Central Floridian.......
Im one of the dozens who have built one of the Predator Harbor Frieght bikes. Mine is a 99cc put onto a Micargi Rover beach cruiser. It weighs in with me on it at about 240 lbs, Im guessing. With how I have the gearing on it at 9.6/1 with a Q-matic tranny, I have hit 42MPH at 5200 RPM. I rarely and I mean rarely push it that fast because I would like for my new build to last a little while. However I consistantly run it at 4500 RPM for an hour or 2 at a time without any struggle or worry. At 4500 RPM I run 36 MPH which is more than fine with me!http://http://motorbicycling.com/showthread.php?t=38434

Prior to this build I did start with a 66cc 2 smoke kit and probably worked all the kinks out of it, but got fed up with tweeking the build all the time and made the decision to go with the Predator motor and test my fabricating ability. Im very happy I did and will not go back to 2 stroke except to put the old motor on another bike and probably give it to someone.
 

Ibedayank

New Member
Oct 29, 2011
1,171
0
0
Columbia Tennessee
Thanks all...yes, the Predator 99 it sounds like a winner, what do you believe the HP rating to be?

So why do you need the Q-matic?

I have been building recumbents for over 20 years, my favorites are tadpole trikes, but I have been getting into the 4 wheel bikes,
I bought this one the other day that looks a lot like the old Briggs and stratton 5 wheeler,
the 5th drive wheel is like a trailer in back, it had an engine in the side, I want to do something like that seems the predator 99 would be a hot ticket,



I have to wonder how heavy the B&S design was, I am guessing the engine and drive parts would be more than the new predator 99,

My plan was to use the rear swing arm from a discarded mountain bike, it will give me a nice looking frame, and pivot,
But I planned to just use a clutch on the engine to a large sprocket on the side of the wheel, I know from my go kart and mini bike days that is good from take off to...??? well, faster than I want to go on this thing,

Which brings me back to why the extra Q-matic thing?

well for starters how big are the tires on a minibike or gokart?

its all about overall GEARRATIO you try and run small minibike sprockets what you gonna get is a fried clutch

type in the search bar ,, Qmatic lots of builds here use a qmatic

you can have pulling power or speed you can not have both... unless you run something that can change your gearratio on the fly
 
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the13bats

New Member
May 3, 2012
24
0
1
Orlando
well for starters how big are the tires on a minibike or gokart?

its all about overall GEARRATIO you try and run small minibike sprockets what you gonna get is a fried clutch

type in the search bar ,, Qmatic lots of builds here use a qmatic
Maybe, maybe not....
"IF" I took a Go kart wheel and sproket ( size isnt an issue yet ) and attached it to a "bike, trike, 4 wheeler, wagon etc" as a drive wheel that weighed the SAME as the go Kart and the clutch wasnt fried on the kart it wouldnt be fried on any other contraption that was the same weight.
 

the13bats

New Member
May 3, 2012
24
0
1
Orlando
if you already know all about it why did you ask for help?
I never said I know all about it...I always enjoy seeing how others tackle a problem.

I asked a lot of things and you tried to answer one question about the q-matic with a vauge reply for me to do a search and it's about gear ratios,

I more wanted a reply about why the "q-matic" specifically,
Not taking anything away from it but what I saw could be built in any good home shop in a few hours for cheap.

I asked all kinds of questions and have lots more, I would love to see how some people tackled adding an engine to a trike....
 

the13bats

New Member
May 3, 2012
24
0
1
Orlando
what trike granny... tadpole.... delta...
can't read your mind dude
Hah...you called me Dude....Well...gee have you read any of my posts?

Almost every one mentions I dig Tadpole tikes,

HOWEVER,
I believe if you were reading my posts you would have known I want to power a 4 wheeler, the rear ( as you know ) has two wheels a kin to a ( delta ) trike with two wheels, then you would understand ( had you been reading my posts ) why I asked to see how people powered trikes and you would have ( maybe ) deducted that the trike would be delta...

I know now you will tell me to go do a search for powered trikes....
 

the13bats

New Member
May 3, 2012
24
0
1
Orlando
Sounds like a fun one to do,
I scratch built many deltas then tried tadpole and was sold, I learned tadpole is one of the top handling lay out there is,
Hence the Can ams..

Your delta will be nice to haul dog food etc, you might want to play with steering geometry so it's not weird at speeds with the engine power,

The biggest delta I built was powered by a full tilt VW race engine, it would wheelie at any speed...not always a good idea.