Sand Rover DONE! (finished pics pg 7, sand video pg 10)

[yoothgeye]

Took a little break from my build off bike tonight to start the staging of a bike I want built by a labor day trip to the beach.

When I was pre-teen to early teen we use to take our bikes to Virginia Beach on vacation. Dad and I would cruise the boardwalk, in the evenings when the beaches weren't as crowded we would carry our bikes over the soft stuff and ride on the packed wet sand at the surf line. I always tried to ride the bike through the soft sand back to the boardwalk... it never worked.

At some point in a Popular Mechanics magazine or something I saw a big wheeled mountain bike for the beach, using those big pnuematic sand tires used for catamaran or jet ski beach landing trailers. It was a cool idea, just real expensive.

Within the last couple years I was checking out photos online of a guy riding the soft sand on a North Carolina beach on a Surly Pugsley... once again, cool idea, awesome bike... real expensive.

So I plan to build a bike capable of riding in some sand better than my mountain bike, but do it cheap. The idea finally came to fruition when I picked up a Schwinn OCC Chopper Stingray bike for $20.

It can be seen here: viewtopic.php?f=16&t=41380

I don't like these things and didn't really have any ideas of what I would do with it... maybe just flip it? Part it? As I looked at it more I started thinking that the wide rear tire at the right pressure on the right bike might do ok in the... sand?

So tonight, I started the process:


Removed the fork and gave it to a friend (pictures to follow) then took off some other parts, then did this:


Ohh, this is fun... next:


I will be putting the big wheels on a 20" BMX style frame. First I will cut off the rear chain/seat stays off the 20" frame and weld the rear stays from the chopper bike onto it. Then I will have to fabricate a simple fork to run another rear tire (which I don't have, currently looking) up front with the freewheel removed.

Next I will have to worry about drivetrain. The chopper bike runs a wide 3 piece crank, which I cut off. Once the back wheel is attached to the new frame I will slide the removed BB through the 20" frame american bottom bracket, line up my chain, and weld it in place.

Now, I wanted to gear it a little lower, so I looked around the shop. A neighbor was giving me some bikes and handed me this odd-ball part he found (on the left):


A Specialized mountain bike right side crank with removable chainrings. Glad he didn't find just a left side. The cool thing is, even though this is aluminum and the OCC side will be steel, the crank arm design is pretty similar. I removed the big a and little wheels and got this:


I went from a 44 tooth to a 32 tooth. That should help turn that fat tire in the sand:


So if you're keeping up, I'm currently $20 into this project, and hoping to stay close to that. Why the 20" frame? I'm 5' 10" and I still fit a 20" frame ok, plus I thought the little frame would make the fat tires look fatter, and allow my kids to ride it too.

I'll keep you updated!

Oh yeah, my friend Cody, I gave him the fork and he started this tonight:


I bet he won't be able to keep up with me in the sand.

[Con-Tiki!]

if you grind the teeth of of the biggest chain-ring, and stick it back on there, it'll make a cheap guard. I did that on my single-speed mountain bike, and it works great.
Not that your long pants will be getting caught while you're at the beach...

[yoothgeye]

if you grind the teeth of of the biggest chain-ring, and stick it back on there, it'll make a cheap guard. I did that on my single-speed mountain bike, and it works great.
Not that your long pants will be getting caught while you're at the beach...

I actually started to do just that, but I'm running single speed chain and it would have rubbed the chain (I tried it).

[Dr. Tankenstein]

Sweet concept. Any thoughts of using part of a second rear triangle to make the fork? As long as you're looking for a second wheel/tire, the tubes would match and make it look 'factory'.

What if you cut the legs off a second set of forks at the lower plate and welded part of a rear triangle to it?

Just brainstorming with your $$ and time!

Cheers,
Dr. T

[yoothgeye]

Sweet concept. Any thoughts of using part of a second rear triangle to make the fork? As long as you're looking for a second wheel/tire, the tubes would match and make it look 'factory'.

What if you cut the legs off a second set of forks at the lower plate and welded part of a rear triangle to it?

Just brainstorming with your $$ and time!

Get outta my head!

This had crossed my mind based on if I get just a wheel or a whole bike, it would definitely be easier, the only thing holding me back is that I just like the look of a round tube fork... and I've got a lot of donors.

[Dr. Tankenstein]

Run what ya brung!

If you have forks, then go for it!
Another thing to consider...Not sure if a 'standard' hub will be wide enough for that 4" rim though....hmmm. Since it's a freewheel, I guess you might be able to remove the cog from a second rear hub, dunno, just thinkin'....

Living vicariously through your work.

Cheers,
Dr. T

[yoothgeye]

Another thing to consider...Not sure if a 'standard' hub will be wide enough for that 4" rim though....hmmm. Since it's a freewheel, I guess you might be able to remove the cog from a second rear hub, dunno, just thinkin'....

The plan was just to remove the freewheel and run it as is. Leaving the threaded hub there if I really wanted to get fancy I would adapt a disc brake to go in it't place... but I've never been one for being too fancy.

[yoothgeye]

OK, this project is still alive, but I can't find another OCC Chopper for cheap enough to cut up for the front wheel/fork. I have since decided that instead of building a fork I will be just using the chainstays so that I can retain the wide V-brake so the bike will have front/rear brakes (so you were right Dr. Tank... once again). I really wanna have the other bike before the week going into the Labor day because I want this one at the beach!!!

[FatBoy]

I saw one of these at a local bike shop and it was really cool.It sounds very simillar to what your building.This one looked similar to a 26" cruiser with 4" wide tires front and rear I wish I could have riden it

[yoothgeye]

I saw one of these at a local bike shop and it was really cool.It sounds very simillar to what your building.This one looked similar to a 26" cruiser with 4" wide tires front and rear I wish I could have riden it

Yeah, there's this bike and the Surly Pugsley, both cool fat tire bikes, there's a whole forum for fat tire bikes on the net, neat looking bikes, but they are PRICEY! I should be able to build this bike for less than the cost of one tire and tube on those big boy bikes. I have seen photos of a guy riding one of those on soft beach sand. Cool, I wanna do it!

Still don't have my parts for this build so tonight in the shop Cody added a 3rd 26" wheel to his burrito bike, it trails behind the back wheel making his bike over 11 feet long. It is hinged so it floats up and down over elevation changes in the road, looks really cool. Then we got out my tall bike and welded it back together in it's new 10.5" taller height. I can tell the difference. We went ahead and got it working and rode it all over tonight, it's so fun.

[yoothgeye]

Good News! OCC Chopper bike #2 showed up today, $15, it's the older one with the fold down pegs on the forks. Choppy Choppy!

[kingfish254]

Looking forward to seeing your progress now that you have your parts.

The front chainring on that Spyder is the same one they use on training wheel bikes!

[yoothgeye]

Looking forward to seeing your progress now that you have your parts.

The front chainring on that Spyder is the same one they use on training wheel bikes!

As you can see earlier in my post I have addressed the smaller chainring, but I'm at about 34 tooth, which should be fine with the 20" tires, and looks like the freewheel on the chopper wheel pretty tall too.

[yoothgeye]

OK, if this doesn't get you excited, nothing will.

As stated, the second OCC Chopper bike was procured:


Then I grabbed my donor frame:

(don't cry, I'm saving it's life, not killing it)

Cut up a 24" mountain bike fork to make the WIDE fork out of the donor bike chainstays:


They call these things "choppers" for a reason right? I can't seem not to chop them.


Fork test fit:


Now, when you fit a big wide tire you need a wide bottom bracket, which the OCC has, so how do you mount it? First you clean it:


Then you slide it right inside the stock bearing cups, once alignment is made, the drive side will be welded to the new bottom bracket, then pressed into the GT bottom bracket, then the other cup pressed in and welded to the bike. I will keep the "chainguard" that is welded to the BB facing downward to protect the chainring from bashes by rocks/curbs/logs.


Didn't think about this, but had to lengthen the frame to clear the crank arm:


Chainstay welded in:


Seatstays welded in, mocked with handlebars and seat with original layback seatpost.



(ignore the cheesy seat, I just wanted to sit on it and this was the closest saddle to me.

As you can see, we gave it alot of center ground clearance in case it sinks down the sand some you won't be pedal dragging.

Next time we shall be getting it ridable... SWEET!

This bike really has me excited.

[Carbon]

Awesome! That thing looks tough!!