Losi’s Accidental new Crawler Release - Page 3 - RC-Monster Forums

kulangflow · 02:06 AM

Quote:

Originally Posted by Tempted

The most successful crawlers(1/1) are locked front and rear. Unlocking them causes traction loss and tire spin, neither of which you want when your crawling. How many guys out there are crawling with open diffs? Thats a serious question. Anyone crawl with open diffs?

I think that you're not understanding what gtxracer meant by "unlocking diffs". He means that he can lock or unlock them depending on the situation. Your statement makes it sound like you think he has them unlocked all the time.

No-one crawls with open diffs all the time because locked diffs are absolutely necessary most of the time.

However, some of the time the ability to remotely unlock one or both diffs would be a huge advantage.

Tempted · 12.05.2008, 02:37 AM

When I start seeing comp crawlers winning with selectable lockers, I may buy into the idea. I think its an okay idea on a basher that sees slow off-roading and on-road speed runs but a crawler is going to want all tires pulling all the time. We'll see, I could be wrong.

gtxracer · 12.05.2008, 03:09 AM

Tempted - How many crawlers, RC or 1:1, have you had? Just wondering.

I think you'd be surprised how that feature comes into play. Drive a locked rig and a rig with selectable lockers. You'll see.

lincpimp · 12.05.2008, 03:21 AM

Being able to remotely unlock the diffs is a cool idea, that is for sure

My only issue with the losi setup is that the worm drive axles will not allow the free wheel function that most dig setups allow. It is nice when making a steep crawl, or going up a rock that has an indent at the bottom. Not having drive to the rear wheels can help the truck not experience the rear axle trying to "drive under" the truck. However it is important in this situation to let the axle freewheel, as any resistance may cause issues with the front axle pulling the truck up and over. Only way I can see to do this would be to have a slightly slower ratio gear that could be selected to drive the rear wheels slower than the front. No "drive under" that way, and the rear wheels would still turn, helping the front wheels out. Not sure what kind of setup that would require...complex to say the least. Could be done with a clod/worm axle hybrid that had 2 motors and escs. Have some sort of radio mix that had a bunch of expo on the rear esc throttle to drive the motor slower... I really want to make some worm axles with outrunners mounted directly to the worm... Ultra low cg and a very narrow chassis, with super drag brakes and no driveshafts, plus only 2 gears. Its in my head, just need to make it!

The Worm axles will give great drag brake, and having selectable front and rear engagement is a cool feature. I only play crawl, so no reverse points for me. Should be a big hit with the comp crowd, and most likely much cheaper than the kyosho...

johnrobholmes · 12.05.2008, 09:36 AM

A guy in Oregon makes worm drive with outrunners on them, a worm drive clod of sorts. They are $400 for a set of axles, but super nice full metal.

Open diffs really help in some situations. Locked diffs are really only needed when a wheel lifts off the ground. If all wheels maintain traction then turning is much tighter with at least a front open diff. Just like having dig, a selectable diff is very useful and makes the rig more maneuverable. If I had to choose one option, I would go for dig first probably. But if I had the choice I would take a remote front diff locker and front dig too. Now we are talking about 4 channel radios.

Losi really hit a home run with this one, it looks pretty dang awesome all around.

Tempted · 12.05.2008, 03:41 PM

Quote:

Originally Posted by gtxracer

Tempted - How many crawlers, RC or 1:1, have you had? Just wondering.

I think you'd be surprised how that feature comes into play. Drive a locked rig and a rig with selectable lockers. You'll see.

Two 1/1 crawlers FTR. My all purpose truck that I used as a crawler was a Detroit locked 14 bolt rear and full spooled Dana 44HD front. Almost every single time I went off-road I locked the front hubs for a completely locked front end. And every time I crawled I locked the diffs. Bar none. I went places I could never go with an open front diff and I never had to unlock my front to get somewhere. I crawled with people who had open diffs and had to winch them out half the time. If you are making a U-turn on asphault then sure, unlock a diff. Otherwise its a feature that will never be used on a true comp crawler.

johnrobholmes · 12.05.2008, 04:09 PM

Quote:

Otherwise its a feature that will never be used on a true comp crawler.

Sure it will. Sounds like you haven't competed before. Gates are set up so tight that you have to turn 180's between them sometimes. Let us say there is a gate facing downhill, with the next gate set up so that you must turn a 180 in a 4 foot circle and go back up the same way you came. An unlocked rig could do this pretty easy without a reverse, a locked rig could not. A rig with front dig won't have any advantage, as the dig will just make the front end slide further downhill.

Big difference between crawling and competing. You can reverse with no penalty when just crawling.

Tempted · 12.05.2008, 05:17 PM

Thats true. Like I mentioned, if you have to do a U-Turn on asphault then sure it would work. If your turning on dirt, or any other loose surface, the inside tire will spin. By blipping the throttle you can usually pick the inside wheel up and turn on a dime. Just my experience.

johnrobholmes · 12.05.2008, 05:30 PM

They are called ROCK crawlers for a reason,

Takedown · 12.05.2008, 05:34 PM

Wow looks really nice.

TexasSP · 05:43 PM

JRH, maybe you can answer this for me but I am having a hard time understanding how dig and the worm gear setup will work together. When using Front Wheel Drive only how wheel the rear wheels free wheel and allow movement. It would appear to me that with the worm drive it would lock up the rear end. Don't get me wrong, I like Losi's new truck, I am just trying to see what I have missed in the equation.

Tempted · 12.05.2008, 05:42 PM

Quote:

Originally Posted by johnrobholmes

They are called ROCK crawlers for a reason,

Sure, but when your crawling you want them locked all the time. Its flat ground we are reffering to.

Arct1k · 05:44 PM

That is the idea - The front wheels drive whilst rear locked pulling you around - this gives you a tighter turning radius.

kulangflow · 06:30 PM

Quote:

Originally Posted by Tempted

Sure, but when your crawling you want them locked all the time. Its flat ground we are reffering to.

You don't necessarily want them locked all the time when crawling.

On the courses, there are often flat parts (like plateaus, etc) on the rocks where you need to make the U-turns for the gates. It's hard to explain, but I'll see if I can find a picture unless someone else finds a better way to explain it.

Edit: This is the best I could do:

On the top part of the picture (the u-turn between gates) it's a flat section where an unlocked diff would work wonders. It's kinda hard to see the grade of the terrain from the picture, but several of us mentioned wishing we could unlock our diffs for those two gates.

BL_RV0 · 12.05.2008, 08:18 PM

Anyone know how long it would take to lock/unlock a diff? Like 1 second or???