What is your experience with significant increases in unsprung weight and rotational mass? (1 Viewer)

[jreichek]

What is your experience with significant increases in unsprung weight and rotational mass?

I have been doing a bit of research regarding the issue of Hutchinson beadlock wheels for my vehicle a 2005 Lexus LX470 (same as a 100 series Landcruiser). (For a 2 page thumbnail picture gallery of the vehicle with complete specifications of all the modifications on page two please visite www.reichek.org/lx3v )

First I weighed an existing 285/65/18 Cooper A/T3 on one of my Lexus stock wheels (a brand new rear mounted spare). The combined weight is 87.1 lbs

Hutchinson beadlock wheels for the 100 series weigh 39.4 pounds each.

Cooper AT/3 XLT 305/70/r17 tires weigh 61 lbs. (combined weight 100.4 lbs)

Cooper AT/3 XLT 285/70/r17 tires weigh 56 lbs. (combined weight 95.4 lbs)

That is either 8.3 lbs per corner or 13.3 lbs per corner of additional unsprung weight and worse yet -rotational mass.

with 4 corners, that is either 53.2 or 33.2 lbs of additional unsprung weight.

At a rule of thumb of roughly a 10:1 ratio of effect between sprung and unsprung weight (and even higher ration of effect for rotational mass), upon mileage and handling (and a 3:1 effect on acceleration, and braking) -- assuming this is a reasonable rule of thumb, that is equivalent to adding between 332 lbs and 532 lbs to the sprung vehicle weight (and even more to the rotational mass)

The "math and science" of unsprung weight

https://www.cjponyparts.com/resources/what-is-unsprung-weight

What is your experience with these kinds of significant increases in unsprung weight and rotational mass?

Best regards and respects, Joshua

 

[bozncsurf]

Amazing build!

A lot of thought went into your set up. The rear cargo area is full of surprises. As a Slee rear bumper owner myself I couldn’t help but study all the mods you’ve done to it. Mind blowing actually.

What are you using for swing out latching ?

Not to completely derail your thread I am a big fan of the proportions of the 305/70r17.

Good luck!

 

[Corbet]

MPG goes down and acceleration is reduced. Neither of which may be noticed much depending on your driving style and/or other factors. Personally lift height has had the most effect on the MPG of my truck. Adding heavier MT's didn't change the MPG nearly as much. It's also going to effect braking performance.

Hutchinson Beadlocks are really nice and I want a set too. But do you need headlock wheels for how you use the truck? Not that need really plays into much of what all of us do to our trucks

 

[bigredmachine]

I would think that the slight increase in weight compared to the rest of the truck is going to be insignificant. if your worried about stopping distance the total weight of the truck is going to be more of a factor

 

[jreichek]

Amazing build!

A lot of thought went into your set up. The rear cargo area is full of surprises. As a Slee rear bumper owner myself I couldn’t help but study all the mods you’ve done to it. Mind blowing actually.

What are you using for swing out latching ?

Not to completely derail your thread I am a big fan of the proportions of the 305/70r17.

Good luck!

Dear bozncsuf, Greetings. Thank you for your observation and online examination of my vehicle. Your encouraging and complimentary words are appreciated and welcomed. I do not remember the specific make etc. of the Slee swing arm latches we replaced. The ones that Slee provided quickly rubbed/abraded/vibrated themselves right through the stirrups - they were subpar. Gary Kardum of Mudrak Custom Cruisers in Sonoma CA. selected and installed them - He might remember. You can contact him directly, I will also contact him and ask. If he remembers I will post it to the specification in the picture gallery www.reichek.org/lx3v

 

[jreichek]

Dear bozncsuf, I have contacted Gary at Mudrak, The Latch Clamps he used are Southco # 00-149-0211 see attached

 

[hiluxjeremy]

Unless you're routinely blowing beads I don't think you'll find the continuous compromise of the extra weight worth while.

If you have to ask, you don't 'need' a beadlock.

I know 4 people first hand who've had Hutchinsons 3 out of the 4 guys I know ended up selling them. Two were avid wheelers, one truck was an 80 on 37's, one was Sas'd 1st gen taco on 37's. The third guy was a casual now and then family wheeler, sold them on a truck and never looked back. His 35'' Kenda mts with Hutchinson wheel combo wasunreasonably heavy/awkward for a single person to mount and dismount from rear swingout tire carrier.

The guy that kept them has a 2nd gen Tacoma on 1 ton diffs running 42's.

Numbers are one thing, but this is what I've seen.

On the other hand, the only way to really find out for yourself is to try it.

The day to day penalty in economy and all round performance of a heavier than required tire combo doesn't add up for me. The same truck with two very different setups feels night and day to me.

But thats just my two cents, its not all about 'need' either.