Weight Bias in Climbing Capability?

[TeCKis300]

Why do some builds and vehicles climb better than others? Here's a look at some key parameters outside the usual lockers and suspension discussions.

The first half of this video shows some pretty dramatic differences in climbing ability. Pretty dramatic what a little toy can climb relative to it's own size.



Observation of something not usually talked about? - Weight bias

Seems to play a big part. On a 4x4, front weight bias can help. Or better said, more rear weight bias with a lot of gear may compromise climbing capability. I couldn't find the spec on the 200-series stock but some scales show it to be ~52% front biased. With added build and cargo, can substantially make it rear biased, reducing climbing performance. I suspect this is why Tacoma's, with relatively light weight, long wheelbase, and front bias upwards of 55%+ climb well.

And of course the more usual lower center of gravity, tire diameter, and tire grip.

 

[lovetoski]

So dual battery, bull bar and winch could improve climbing? LOL justifying future upgrades....

 

[TeCKis300]

So dual battery, bull bar and winch could improve climbing? LOL justifying future upgrades....

Yup, but leave the goodies off the rear

 

[bloc]

Is there a point at which we make climbing physics so good that we harm our ability to descend steep obstacles safely?

 

[TeCKis300]

Is there a point at which we make climbing physics so good that we harm our ability to descend steep obstacles safely?

That's a good point. Likely yes that front bias could effect stability and braking capability to a degree. But going downhill has the benefit of gravity so it's much less about traction to overcome obstacles, allowing rigs to tackle much steeper grades in that direction. Inclines needs traction to work against gravity and obstacles and probably becomes the limiting capability. Could reverse downhill...LOL??

 

[bloc]

That's a good point. Likely yes that front bias could effect stability and braking capability to a degree. But going downhill has the benefit of gravity so it's much less about traction to overcome obstacles, allowing rigs to tackle much steeper grades in that direction. Inclines needs traction to work against gravity and obstacles and probably becomes the limiting capability. Could reverse downhill...LOL??

I’ve been on a long, loose, beach type sandy downhill stretch before and puckered like crazy by the rig not wanting to stay straight. Not sure whether different weight distribution would help.. but sometimes traction downhill can be an issue too.

This was my v8 swapped 80.. armor, winch, light load, mud terrains, but the front was over a hundred pounds lighter than stock because of that engine swap.
Ultimately it was more capable than I was. Got me thinking about big loose hills and how best to approach them though, even pointed down hill.

 

[40Man]

Why do some builds and vehicles climb better than others? Here's a look at some key parameters outside the usual lockers and suspension discussions.

The first half of this video shows some pretty dramatic differences in climbing ability. Pretty dramatic what a little toy can climb relative to it's own size.



Observation of something not usually talked about? - Weight bias

Seems to play a big part. On a 4x4, front weight bias can help. Or better said, more rear weight bias with a lot of gear may compromise climbing capability. I couldn't find the spec on the 200-series stock but some scales show it to be ~52% front biased. With added build and cargo, can substantially make it rear biased, reducing climbing performance. I suspect this is why Tacoma's, with relatively light weight, long wheelbase, and front bias upwards of 55%+ climb well.

And of course the more usual lower center of gravity, tire diameter, and tire grip.

Didn't watch the video, but agree with most of this, although my personal experience is on steep climbs trucks end up not being as great, particularly on more loose terrain, as the front bias is too much.

When I first started offroading lot back in the day my buddies looked into this, and as I recall, the consensus at the time was a slight front heavy, similar to what the LC is stock and maybe a bit more (52-54%) was the best overall balance. I had a Tacoma, and it was a beast, but really steep climbs were tough compared to friends Broncos and Cruisers, even with a rear locker as the lighter rear end could lose traction, even with the weight pushing in that direction.

It would be cool to see some real world research as there are a lot of variables.

 

[Sandroad]

Fun video As I see it, our 200s need center articulation. Mine's still under warranty, but surely there is someone out there with a torch, a welder and an interest.

 

[AnyMal]

As far as climbing or scaling a slope i would imagine smaller tires for a lower center of gravity and front bias on both up and down.
The interesting part would be to find the grade and distribution curves at which rear traction become suboptimal and work out the sweet spots.

When it comes to climbing over and on top of an obstacle I think large tires and rear bias no?

Thats a great channel btw.

 

[bloc]

They made a good demonstration of larger tire diameter approaching a step at a better angle. Basically it is already angled over the top vs hitting it in the front. Thing is it would need to be a significant difference in diameter to have a noticeable effect, and this would be tough to do on a 200.

But, simply increasing tire diameter 2 inches means one more inch of clearance under the axles/body/chassis. Clear advantage.

 

[linuxgod]

Why do some builds and vehicles climb better than others? Here's a look at some key parameters outside the usual lockers and suspension discussions.

The first half of this video shows some pretty dramatic differences in climbing ability. Pretty dramatic what a little toy can climb relative to it's own size.



Observation of something not usually talked about? - Weight bias

Seems to play a big part. On a 4x4, front weight bias can help. Or better said, more rear weight bias with a lot of gear may compromise climbing capability. I couldn't find the spec on the 200-series stock but some scales show it to be ~52% front biased. With added build and cargo, can substantially make it rear biased, reducing climbing performance. I suspect this is why Tacoma's, with relatively light weight, long wheelbase, and front bias upwards of 55%+ climb well.

And of course the more usual lower center of gravity, tire diameter, and tire grip.

If only I could flex like that. Or as George Carlin once said, "The stewardess says to put my seat back forward? If I could do that I'd be in pornos!"

 

[Lester did that]

I never thought about the math but in my experience after I installed the bull bar and winch it was a lot easier to ascend trails that normally would cause some slippage. To be fair before the install I had a large drawer system filled to the brim in the back. The bar and winch weight in the front is more than the box in the back. Common sense would tell ya if the back is loaded heavy your going to have issues grabbing in the front. I think I am around 53% in the front?

This thread has got me thinking. I'm going to bring some weights with me. Test it out a little more.