A couple briggs style bikes

[Motormaker]

Here are a couple bikes I built this summer. I like to try different things mechanically.

This is a 26-inch " La Jolla cruiser" from Wal-Mart. I chose it for it's coaster brakes and no cables, gear changers etc. I like a clean look. It is an aluminum frame, which is a bonus. I used a 3.5 hp Briggs & Stratton engine. A go-kart style centrifugal clutch was used with #35 chain. The "side pusher" type design track's very well. The small tire takes all the weight of the engine so it doesn’t feel heavy when riding.

These photos were taken before I installed a twist grip mini-bike throttle and a handle bar mounted kill switch.

The motor assembly pivots where it mounts to the bike. You lean to turn just like a normal bike with two wheels. The wheel-motor will move in a scissor type action as you lean.

The bike will let you know if you take off to aggressively. The lack of weight on the drive tire will cause it to buck and bounce wildly. However if you give it 4 or 5 quick turns of the pedals then keep a light hand on the throttle she will buzz along at about 24 mph for miles and miles. More on the other bike later. MM

 

[comfortableshoes]

That is a very nice design for a pusher type motor. I like how tight it is to the bike, very minimal design too. Clean build. I like it!

And it must be a 4 stroke?

 

[stude13]

thats very cool. i tried to build a pusher last month and it was a complete flop.

 

[deacon]

I like that idea a lot.... The more original the idea the better it is in my opinion. Also not to worry about failure when you least expect it something you learned in a failed build will help with a new build. It all about the learning.

 

[vernon/retiredtinkerer]

nice job motormaker, simple and slick, i wonder if some kind of shock absorber or spring tension would help it stay on the ground when you want to gas on it??? vernon

 

[OSCAR383]

Simple I Like It

 

[Jemma Hawtrey]

Its a nice machine and a lovely bike - but not all that original in concept.

The Wall Motor Wheel used this system in 1910 with what looks like a solid 16/20 inch wheel and, I think, a 211cc single cylinder motor clamped to the cycles superstructure.

Its actually a full circle job - because the two guys who took over production of the Wall machine were a Mr Briggs and a Mr Stratton...

Incidentally to get rid of the axle tramp on fast starts - you can get hold of the mid frame damper units for MTBs as a replacement unit. Make up a mount to the bike and a connect tho the engine unit and that would help with that particular problem.

Jemma xx

 

[Motormaker]

In reply to "Shoes" Yes it is a 4 stroke. However I am looking into making a two-stroke 50cc version with a pocket bike engine. (To be street legal in Indiana) Another idea I had along these same lines was to use the engine, torque converter, rear wheel assembly from a 50cc scooter/moped. It would just be a matter of simple bracketry. Also in regards to "Vernons" comment: I am looking for a mono-shock assembly from a scooter for that very idea. (Great minds think alike) It will also help with the problem of the whole thing falling over when parked. No "Jemma" the concept is not new at all. The execution is. The Briggs and Stratton motor wheel had the motor situated beside /inside the wheel. The motor wheel also had no clutch. The whole assembly was lifted off the ground to allow the wheel to spin in mid air. My design is much closer to the Popular mechanics/Mechanix Illustrated version from the mid 1950's. I simplified that that design further because I have the ability to weld and with today's aluminum block 4 strokes I could do more with less. And the Popular Mech. design seemed clumsy and inelegant to say the least.

For the unknowing here is the B&S motor wheel for bikes.

There were many uses for the Motor wheel.

 

[stude13]

could you give us some close ups. i have a boreem scooter. the motor is mounted on square tubing. because of starter im thinking of mounting on other side. did you use a long shouldered bolt as attachment?

 

[Large Filipino]

Dude that is AWESOME!!
I could see a shock absorber (with outer spring for rebounding) from even a car halfway down that arm to the upper half of your bike frame.
Man I wish I could weld.

Sorry for my evaluation here because it's a great design but have you thought about theft? It looks like one bolt and it's all theirs.

 

[Motormaker]

Yeah, "Stude" Here are some detail shots.
This shot is of the frame mount itself. It is a section of shallow channel iron with a kick bent in one end. Holes were drilled for the axle and for the "U"-bolt. A 3/4-inch double nut was welded to the center of the channel iron. The nice part about this mount is that the bike is not modified in any way, and in 5 minutes it can be removed.

I tore it down for prep and paint. The powered wheel came from northern tool. It had bearings and a sprocket installed when I purchased it. The axle is a 3/4-inch bolt. The pivot bolt is also 3/4 inch.

"Filipino" If someone want's to steal the drive unit by removing the pivot bolt they are a better man than I. Wink Wink.

The pivot bolt is welded to the motor unit and the Double nut is welded to the frame mount. The "swing" action is the bolt and nut screwing and unscrewing ever so slightly.

The boreem style scooter would be a perfect donor. Gas or Electric.

I thought and re-thought and then thought some more to simplify,simplify,simplify. I didn't want to use 5 parts when 3 would do. I subscribe to the "less is more" school of design. I like the super clean look I ended up with.

 

[stude13]

kiss is the way, thanks.

 

[Motormaker]

No problem

 

[NEAT TIMES]

Motormaker, Thanks For Sharing. Very Neat Setup. Great Pics.

 

[carbman]

what size tire & wheel did you use from northern tool

 

[Motormaker]

The one I used is a 4.10/3.50-4. A 4.10/3.50-5 could be used for a slightly higher top speed. Hey if you happen to build one like this post a photo for us. MM

Low Speed Wheels | Low Speed Pneumatic Tires + Wheels | Tires + Wheels | Northern Tool + Equipment

 

[carbman]

thank you motormaker i plan on building one this winter for my home built recumbent. I have a 5 horse briggs so Im going to use the big tire & wheel.

 

[NEAT TIMES]

Harbor Frieght: 2 1/2 Hp Greyhound Motor $99.99 Item # 97964-ovga . Should Do The Job . Clutch And A Wheel/with Sprocket From Northern Tool And Equipment.

 

[Motormaker]

That would be perfect. And closer to legal. The 3.5 was the smallest 4 stroke I could find at the time.

 

[stude13]

with your inspiration and a dream, i put one together in an hour for 85 bucks. cut a boreem goped $25 and bolted it to an occ chopper $60. and it cooks. thanks mitch