Rebuilding the Mini Rock Crawler Project - Part 1 

Those bricks need to be awarded a medal for all the hard work they put in!

63" is the sweet spot bud. Many trails are limited to 63" because of bridges, etc.. The new tires being so much taller will help your top speed also. Looking good, keep up the good work!!

I think one of your projects needs to include some chain drive portal axle ends. I think that would be really slick and would take a lot of the load off the tiny ATV size drivetrains you put on these and give you tons of ground clearance!

Chris, thanks for bringing this back. I really enjoyed this build

Just as a first visual impression, looks way more proportionate. Looking forward to see where you go with this build. I enjoy your content. Thanks man.

As long as it's not using an automotive based engine, I'd say "Mini" fits it fine. After all, the lifted UTV scene still call them UTV's despite HUGE tires.

ROCK CRAWLER IS BACK 🔥🔥

The Polaris front diffs (pre viscolock) used a plastic caged sprague bearing style system for the front diff. The front turning slower is correct and your research is correct as to it being as designed but the reason exactly is the sprague engages when the driveshaft spins faster than the tires (no traction) and is disengaged when the driveshaft spins slower than the tires (traction). Think of it like a 3/8 or 1/2” ratcheting head on a handheld tool. That gives you less wear when 4wd is on and not needed,but the engaging and disengaging is what breaks them. The issue is those plastic sprague cages are brittle like glass and the older they get the worse. Look into aftermarket aluminum sprague cages and do NOT use OEM or Chinese axles. They are as fragile as the plastic cage. Find something like Gorilla, Rhino or SuperATV.

Massive update. Very busy, tons of progress. Those tires are insane.

I was going like "Why the hell did you you put diffs in a rock crawler?! Also those diffs are obviously faulty!" at the going into the garage shot before you explained the CV joints broke 😅

when i built my mini didnt have much cash so . ended up using suzuki Samauri axles and transfer case mated to a t5 trans with a rotax 700 triple . for tires 30-10/14 boggers the stock rims that i widen to 8.5 inch them put self tappers in the bead . foa coilovers 4 link front and watts link rear . love it for everything !

Many Quad trails have width limits and I'm pretty sure you're right at them as is. The way you have this set, with the engine and drivetrain, puts the center of gravity pretty low already, so don't bother widening. You'll get through the turns and rocks better as you've set it up.The old electric steering from the other buggy should work better in this.There should be a rheostat in the power input for it to increase it's torque. Seeya.

I’m liking where you’re going with this project.

Outstanding upgrade. Nice work!

The simple reason for the different final drive ratio's front and rear is to compensate for the front and rear tyres being a different size on the 450 quad

Not sure if you said anything about this, but most rock crawlers have locking differentials, or are mechanically locked. It kills your turning radius, (one of the reasons many have 4 wheel steer) but they perform much better on the rocks.

paint job to those frames or powder coating will add a nice touch to your vehicles! Also have you ever thought on building like a full size project? big engine, big power..

Chris, you have the right attitude!! Laughing your ass off as the thing is being difficult. Evidently, the transfer case uses a viscous coupling. my first thought was smaller front wheel diameter than rear. Another note... Universal joint face at front and rear of each propeller shaft need to be within 1° of one another on the same shaft. More than that can result in u joint failure and/or some vibration in the drive train, especially under acceleration.

B welding Rock Buggy returns!!

Looks so much better man!! Bet it will preform better as long as you have the power. 🤙🏻 Love your videos been watching for years.

better make sure that front diff works. I just rebuilt that same one and the rollers inside have to be able to move freely. Can't make it too wide not to fit on your trailer.

24:37 I love watching your brain at work with the heavy mods I envy you to be honest

A crazy idea would be to paint things before they rust....

Over/underdriving the front wheels can also be a tuning aid to improve handling. Its probably not something you need in this application but it does have its uses.

Looks so good with the bigger wheels🎉

Great job as usual, just a quick note, when you're building your new shop, please make accomodations for a sandblasting booth 😊

Midi rock crawler 😂😂😂❤ And check how wide your trailer is 😊 so it will fit on the trailer 🥊🥊🇬🇧

that's a pretty nice chassi. next build, use that and automotive parts, Expedition rear independent suspension, S10 or Ranger trans & transfer case and a V-tech. it should rip and be quite durable

I have the same exact jumper. They are awesome!

That was a great idea cutting the housing down . It still looks factory & not soo bulky. You know what your doing for sure .

You should look more into the single seater sand rail parts available. People have been building street bike engine powered mini sand rails for thirty years that I know of and some of those put 200+ hp to the ground, some strong compact parts! The Porsche axles they use often on them will hold several hundred horsepower!

Keep it narrow to get through the ATV trails but air down the tires and run water in them when you’re going to really crawl it.

I would love to see you finish this with paint and make it a finished project. This was always my favorite build.

Keep it narrow for now and see what breaks. Also, look into a rekluse clutch, it will help you offroad as you don't need to use the clutch to take off anymore. They are expensive though and not sure if it's made for the sv650 engine.

You might think about gussets for the tab mounts

I could watch the cleaning time laps ALLLL DAAAAY!

You built a giant world leader toys crawler 😮😅😅 wobbly tires and all but it's awesome 👌

Love it so much keep it up as always 💘

Mini rock crawler is good still I’d say, and 64” is ideal for east coast trail riding.

I don't know about the new stuff, but generally the four-wheel drives I have had, would have something like a 4.11 rear end and a 4.10 front, so the front end will spin just slightly faster than the rear to drag the vehicle around

Absolutely upgrade the hubs and widen it now. It will be less work in the long run, because those old ones are definitely going to break. Same situation as using those tiny 250 diffs on a vehicle that probably weighs 800 pounds. Just make it strong so you have a chance to use and enjoy it.

Widen It and use those cv and make it 4 wheel steering. Definitely still a mini crawler.

Chris I think the Mini Rock Crawler is one of my favorite builds on RU-vid I really do like it out of all your builds I have it the most 😊😢😊

A big thank you to the guy who sent in the stuff to help you along with the project and also enhancing our viewing pleasure.

You should make a four wheeler. It would be nice to see how that would work out!

Tires look good! I say keep the width as is.

More than once I have wondered if you've ever considered mounting a winch on some sort of heavily constructed, welded up steel structure securely attached to the back of the shop directly across from the door. It could be used to pull vehicles up into the shop, but also with some securely mounted pulleys up near the roof it could help to lift and lower heavy parts like engines and such.

29:22 that looks sick

Big fan of your builds Chris, but sorry to say something negative that rear axel is a lot of work that a second hand $100 different would solve? And it would be lighter and stronger. Going to look awesome on those wheels though!

Hell yeah, big tires and beadlocks, finally you'll be comfortable enough to drive with low PSI, right? keep up the good work bro😁

if you think that clutch was screaming for dear life before..... i bet it melts down on his first off road trip

It'd be great to see what that rig could do with a complete suspension. Right now you have shocks but no springs. Springs are what handle the ride characteristics, body angle, ride softness/firmness etc. while shocks dampen and control the motion of the springs. You only have shocks so the suspension on this rig is always lopsided and wonky.

Diff ratio/wheel rotation can be equalled out with tyre profile changing the rolling ratio..

For that front diff, it can surely work if there is a one way bearing (like on bicycle) so that the front wheels can "free spin" in the forward direction. Once the rear starts slipping, the driveshaft it will start spinning faster, so the front wheels will get engaged. Maybe that is the way it works? But in that case, the 4x4 mode would be in forward direction only. Or maybe there is some other interesting mechanism? :)

Since you are redoing things, i would have put the differential higher up and the hubs lower at a similar angle that the control arms would have been but made it solid like you did so your center ground clearance is much higher. It would be similar to a hummer but a live solid axle.

You need to get some of that wipe on clear coat for your projects, it would help slow down the rust. until you have finalized them and paint them. This is my favourite project of yours even though it had many flaws.

Im excited for this!

Samurai transfer case and axles!!!!!!!

Holy build resurrection Batman!

Looks like a mini rock bouncer

Looks great with those larger wheels. Think you are going to have to change that gearing if you want to go over 20mph!

Polaris makes quads with chain driven front differentials , I believe it might be the sportsman 425 magnum or something like that, with all the smaller type engines you use that might be a better choice for your drive train or even on another project you do down the road it would be cool to see you use a chain driven front and rear differential with a jack shaft and it just be full time 4x4 .. anyway great work all the way around love the stuff on your channel

I do think widding the wheel base would improve it and make it look it a little bit more aggressive looking.

Great video 💯👍

I definitely appreciate the work to this happen but… you could always cram some Dana 30s from a jeep under there ;) I’d imaging you can get them dirt cheap.

I would play with wheel spacers, before I spent all the time/money modifying the axle cage.

Of course you have to mod the new differentials!

What you could do to see if it looks better with a wider axle is to make some temporary hub mount extension that bolt onto the original hub location that way you can see if it is better or not and if it is only a smaller modifications is required as you could use the temporary hub extension to make a permanent wider axle

the engine isn't bad, I have the same in my bike, the 2014 V-Strom 650, and for lightweight stuff, it's perfect, but a rock crawler isn't as lightweight as a motorcycle, so idk how it performs in this usecase. btw, really fun bike to have, as it's capable of doing everything I want to use it for as a beginner on 2 wheels

Stoked for this!! I’d be so stoked if you checked my latest supercharged wheelchair build out and let me know what you think 😁👍🏻

Let's go! Been waiting for this one.

Nice work. While you are cleaning all the bits up, you should paint them as you go, as you know what bits already work and what bits wont be changed, so may as well start doing that now, rather than having to strip the whole thing down later again and doing it then.

I think keep it simple keep the original hubs and it's current width. Those hubs should be OK.

You Underestimate that awesome 650 Suzuki engine mate Got the old Vstrom and shes awesome

You should make the axle angle down to the hubs. It would give you more ground clearance. At least angle it about 2 inches

Next time you rebuild it use Suzuki Samurai axles

19:00 bro just made a sick looking bumper lol.jk jk sick work bud

I want to see 4 wheel hydraulic steering 😆

Use dry lube spray on the hyme joints to lubricate them without using grease/liquid

You definitely need to get rid of those air shocks and put some normal spring shocks.

track width needs to be at least double the tyre height. 32" tyres, needs minimum 64" width for stability. Love it btw. Legit.

I think its wide enough. It needs to be able to fit through your door and on your trailer and a razer is a side by side yours is a simgle seater. Its still mini compaired to rock crawlers, it is getting close to a side x side in size though.

Widen enough to use factory length CV shafts...easy to source when talking replacement parts. Also, while you're at it any considertion to raising the diff in relation to the hubs? Sorta pseudo portal setup and could drasitcally increase clearance under the diff.

Man you need to find some like samurai axles or yota axles, maybe some jeep d30 axles and do rear steers

The new tyres look the part, you can probably lower it now and keep the same CofG

Here ya go

Please widen it and build an arched rear axle so your diff is 4-6" higher than wheel hubs.

Does Brick Aided Design work? Yes-- points to 'rather B welding' channel... were BAD is used all the time... ;P

Roll with it. If it breaks then you can build it stronger with the new bearings and widen it, but for now run what you brung! Just my honest opinion.

You could have integrated atleast 6 more inches of ground clearance if you would have arched the rear truss more.

65"' would be good and as for gearing i would do the math to have it at about 30-35 top end in low 6th gear and then you will probually run out of power in high 6th at about 50-60 i would guess without all the ratios.

Nice work ❤️ for power steering Use what is in it Mini Trophy

well if you are gonna need to make new bearing carrier mounts you could make them a little bit lower then the differetial, you are using cv axles so why not use that for more ground clearence. although that might be a bit more work, and you are already doing a ton for these machines yourself, but thats what i like about this channel

I'm curious if you've ever thought about using steel-it paint? it's weldable as far as i can tell, I've seen a couple of other Fabricators use it to keep from having rust appear. just a thought, do with it what you will. love that the Rock Crawler's back....

Add spacers and see how it looks and handles

I don't understand why he has so many toys just sitting and rusting but then again if he was my neighbor I'd prefer he have multiple toys soi can go over and play w/ him.... Awesome video RBW, keep it up. 😁👍🖤 😂

I would have left as much of the ribbing as possible on the diff. It keeps things from being able to flex and move around which is what causes breakage.

Don't forget it needs to fit on your trailer. Just see what it will do b4 putting a bigger engine on right now. Just go with the width it'll be fine.

I’m not sure how robust your charging system is, but you may be able to just add Prius electric power steering assist to your existing manual setup. It’s a pretty simple setup and Sami guys use it all the time with bigger tires then you have

I love everything that you do brother... Your skills are impressive! My only question is why don't you ever spray paint/ powder coat or even prime any of the frames on your builds? Is it because you are always going back to modify stuff or something? Just curious is all✊