LoBoy Fat Tire Chopper

[graucho]

Been a while since I've posted. I've been busy building electric bikes for the past few years. This one will have a motor, so I decided to come to the place where bicycle motor heads hang out. I'm researching 4 strokes and I haven't came to a decision yet on the set up. I have plenty of room so it will be easy to adapt.

I took it on it's first roll and it is perfectly straight and smooth. I have a single sided rear axle set up to show off the insane rear tire. It's my first try at a single sided axle so I had to figure in a lot of math and calculations to get it perfectly balanced.

First Roll.
http://www.youtube.com/watch?v=Lctcd0rkW8g

Zero Steering Flop.
http://www.youtube.com/watch?v=alQKmadQsgc




http://i284.photobucket.com/albums/l...ike/axle11.jpg

[srdavo]

Looking Good!!

Have you checked out the Harbor Freight 2.5 hp Greyhound??
Needs about 12:1 gear reduction for bicycle purposes. IMO

[Wheres my dog]

Now that is one bike with serious rear wheel stopping power!!!

[ibdennyak]

Ooooh, that's nice. Actually your build kind of looks like my mental picture of my current project.....only with......more attention to detail. I am using a Lifan 50 pocketbike engine....mainly because the narrowness of the cylinder gives lots of pedal clearance. You don't need the clearance, but that frame would be so sweet with a similar engine. Not only that, if you aren't limited to 50cc, your frame looks to have sufficient heft to take up to a 140....all with the same footprint. They seem to be a very durable engine too, althiugh a bit heavy for a bicycle add on.

I'm in the process of moving to Washington at the moment, but I have roots in your area. Maybe in my travels, I may have to take the Minnesoota stroll. I haven't been there in about 10 years...does that make me a bad person????

[motorpsycho]

Now that is one bike with serious rear wheel stopping power!!!

stopping power??
there aint any brakes on it yet!!!
what does the rear wheel have to do with stopping power any-whoo???

[graucho]

Originally Posted by Wheres my dog
Now that is one bike with serious rear wheel stopping power!!!

stopping power??
there aint any brakes on it yet!!!
what does the rear wheel have to do with stopping power any-whoo???

Actually... these fatties are about 80% of the stopping power as a normal bike. (to the bad side)
I always have a front brake for the times I really need to stop fast. You get that big tire rolling and
the centrifugal force wants to keep it rolling. ("manual" disk on the rear) I could change this if I installed "Hydraulic" Disk.
Since these are slower speed bicycles I save the extra 145 bucks on the hydraulic, since stopping isn't a danger issue with my current manual disk set ups.

[graucho]

Looking Good!!

Have you checked out the Harbor Freight 2.5 hp Greyhound??
Needs about 12:1 gear reduction for bicycle purposes. IMO

Thanks for the link srdavo. Is 3600 RPM high enough RPM to engage the clutch and pull the weight. Must be why you need the 12:1 gear reduction? looks like a nice little engine. Thanks.

Name 2-1/2 HP Horizontal OHV Gas Engine
SKU 97964
Brand Greyhound
Engine Stroke 4
Overhead Valves Over Head Valves
Cast Iron Sleeve Cast Iron Sleeve
Fuel Shut Off Fuel Shut Off
Mounting Type Horizontal
Shaft Diameter 5/8"
Shaft Length 2-1/4
Decibel Level 90 at 1 meter
Low Oil Shut Off Low Oil Shut Off
Material Sheet Metal
Shipping Volume 1.377
Item Type Gas Engine
Certifications/Approvals EPA and CARB
RPM Rated 3600
Fuel Tank Capacity .42 gal
Oil Capacity 13.5 oz
Start Type Recoil
Drive Type Direct
Horsepower 2.5

[graucho]

Member hammer5312 asked me in my "paint our bikes thread" where do I get some of my rear tire/setup items. I promised him I'd post some of my links here.


1" Axle
http://www.bmikarts.com/item/1-Live-Axle-4000-717

Billet Aluminum 4 bolt hub on a 4" dia for 4" on center rim bolt pattern
http://www.westcoastminichoppers.com/Page5.html

Brake Rotor
http://www.bmikarts.com/item/8-Brake...ck-05706B-6557

Brake hub
http://www.bmikarts.com/item/Hub-wit...or-600253-6500

Pillow block bearings
http://cgi.ebay.com/Qty-2-UCP205-16-...e#ht_500wt_922

1" shaft collar
http://cgi.ebay.com/4-pcs-1-Shaft-Co...b#ht_500wt_922

Brake Caliper
http://www.bmikarts.com/item/Mechani...per-400281-815

Caliper mount
http://www.bmikarts.com/item/Caliper...et-400287-5829

Wheels

http://www.rockymountainatvmc.com/ty...237&webCatId=8

http://www.atvtiredepot.com/products...%24184.95.html

https://www.3rsalesandservice.com/ca...EELS&pManuf=CC



Tires
http://www.rockymountainatvmc.com/ty...138&webCatId=8

http://www.tiresunlimited.com/ALL%20...ng_asphalt.htm

http://www.rockymountainatvmc.com/pr...FamilyId=24830

https://www.3rsalesandservice.com/ca...IRES&pManuf=CC

[graucho]

Robotics mentoring is finally finished. Time to get building again.

Finished my handlebars. Took the dimensions of the schwinn OCC bars and bent a new pair 25% bigger. Scaled for an adult.
Hand grips will be at 30 inches horizontal. Need to position a little nurling where the clamps are.
I ground the welds smooth, now ready for putty and primer.

[graucho]

OK, OK, finally after 4 months of Robotics mentoring 38 kids (6 mentors total) 4 tournaments (144th place worldwide of 2400) I had put this bike on hold. Then I needed a months break with nothing mechanical. Not even a 10 minute shower head replacement requested by the wife.

I've finally turned the shop lights on again and not getting nauseous of the thought of steel and things mechanical. I currently have 2 GEBE set ups for distance riding so I decided on the 58cc 2 stroke for this bike. "PURCHASED HERE" If I trash the engine I will be able to swap it out with another in an hour. I'm not a fan of the HT's but the 4 strokes were too wide for my jackshaft setup with the engine position being so low behind the pedals. (I already have the wide crank) If my calculations are correct I should be able to putt around about 15-30 mph. Also if my exhaust system works out it should be reasonably quiet. Then to keep things looking clean I'm running the throttle cable and brake cable through the frame.



I'm running the throttle cable and brake cable through the frame.


The handlebars are 30" end to end for a nice stable stance.


Finally starting to take shape with the look I visioned from the start.