Bunny hopping when slashing.

Magicman

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My old 1968 Ford Bronco had a 410 front differential and a 411 rear differential. Same reason, the front turned a bit faster than the rear for easier steering.
 
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NorthwoodsLife

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My old 1968 Ford Bronco had a 410 front differential and a 411 rear differential. Same reason, the front turned a bit faster than the rear for easier steering.
Sir, your classic 68 Bronco had 411's in the back because Ford's 8" rear axle was 4.11.

And Dana Spicer built 4.10 front axles for everyone.

Ford used what was available and strong. Therefore 4.11 in back, 4.10 in front. Miniscule difference.

Engineers design 100 capability with 100 percent eficiency. In a perfect world.

It wan't designed in. It was economics.
 
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Dave_eng

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Suggest you take a moment and read this earlier thread on tire hop. John Deere has done a lot of research on the topic.
Tire hop

It boils down to a resonant flexing of the tire sidewalls under certain conditions.
Dave
 

NorthwoodsLife

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Suggest you take a moment and read this earlier thread on tire hop. John Deere has done a lot of research on the topic.
Tire hop

It boils down to a resonant flexing of the tire sidewalls under certain conditions.
Dave
Thank you for posting that! Interesting.
 

NorthwoodsLife

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Yes Sir they did and for a very good reason.

Maybe if I was as smart as you I would also know everything. :cool:
Magicman, I come across as arrogant sometimes. A flaw of mine.

I wish that I had a 68' Bronco Now!!
 

Flintknapper

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Sir, your classic 68 Bronco had 411's in the back because Ford's 8" rear axle was 4.11.

And Dana Spicer built 4.10 front axles for everyone.

Ford used what was available and strong. Therefore 4.11 in back, 4.10 in front. Miniscule difference.

Engineers design 100 capability with 100 percent eficiency. In a perfect world.

It wan't designed in. It was economics.
^^^^^

All early model Bronco's had a Ford 9" rear end (not an 8") and the '68 would have had a Dana 30 up front.

But yes, the gear ratio's were a product of what was available and not a design feature.

The ratio difference is insignificant and would only be in play when the vehicle was in 4WD (Tcase) and the hubs were locked anyway.

And without power steering.....I can assure you nothing will improve the steering of an Early Model Bronco. I've owned several....and still have one to this day.

halfcab2.jpg
 

Magicman

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I owned a '68 and a '74. The '74 was Auto, PS, and Air. Sadly now they are both only a memory.
 
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mikester

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Magicman, I come across as arrogant sometimes. A flaw of mine.

I wish that I had a 68' Bronco Now!!
Since we are way off topic already what ever happened to "So long and thanks for all the fish!"?

 

NorthwoodsLife

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^^^^^

All early model Bronco's had a Ford 9" rear end (not an 8") and the '68 would have had a Dana 30 up front.

But yes, the gear ratio's were a product of what was available and not a design feature.

The ratio difference is insignificant and would only be in play when the vehicle was in 4WD (Tcase) and the hubs were locked anyway.

And without power steering.....I can assure you nothing will improve the steering of an Early Model Bronco. I've owned several....and still have one to this day.

View attachment 118834
Nice uncut Bronco!

And yes, I meant 9". A great axle btw.
 

ken erickson

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Nice uncut Bronco!

And yes, I meant 9". A great axle btw.
Flintknapper's Bronco is good looking! I like the tire and wheel treatment and front winch bumper and winch.

It does look like a "cut" Bronco to me though. That term refers to opening up the quarter panel wheel well openings correct?
 
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Henro

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Since the OP is from "down under" maybe we also need a definition of what "bunny hopping" means?

My imagination says surging...but hopping seems possible I suppose...just can't seem to visualize it...Tires are leaving the ground? which tires?

By the way, I thought everyone knew slasher meant brush hog...bush hog...rotary cutter...movie character...
 

NorthwoodsLife

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Flintknapper's Bronco is good looking! I like the tire and wheel treatment and front winch bumper and winch.

It does look like a "cut" Bronco to me though. That term refers to opening up the quarter panel wheel well openings correct?
Yes Sir. Most cut Bronco's I've seen have Serious sheet metal cut out. Especially the rear quarter panels, to clear much larger tires. Flintknapper's Bronco appears to have factory wheels and that threw me off. I'm a Jeep guy for decades, and that one slipped by me 'cuz I'm no early Bronco expert. And, because it looks so original. Nicely done @Flintknapper .
 

Boatman

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I apologize.

RE: The slasher definition was my mistake. I apologize for my not checking that the OP was from Australia. Australia is a very different English place. Being an old school American boy here, is my only excuse. Sorry.

RE: Front tire ratio, I will not dispute deeply, because I don't care to. That being said, engineers generally don't design in a 2% difference because that is miniscule with rubber tires. So I don't believe they engineer a 2% faster, factor. We'd have to talk to the Japanese engineers. But it's not going to cause "bunny hopping". An Aussie term too, I suppose. My mistake. IF the front tires wear out faster it's because they constantly side slide in turns, and they carry more weight in a loader use environment. (edit: no brainer... the fronts are smaller and make more revolutions than the rear. ) In fact, if the fronts wear out faster, your 2% just became a negative number in a few hours by your explanation. (edit: So, you're wrong. But I apologize anyway, because 85Hokie is a Moderator and on Staff).

I'll stop replying to foreigners. Foreigners to me, that is.

My apologies. Carry on.

It's called "lead ratio". Look it up, it's a thing. I can't think of a 4wd tractor I've operated in the past 50+ years that didn't have the fronts driven faster than the rears.
 

Flintknapper

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Yes Sir. Most cut Bronco's I've seen have Serious sheet metal cut out. Especially the rear quarter panels, to clear much larger tires. Flintknapper's Bronco appears to have factory wheels and that threw me off. I'm a Jeep guy for decades, and that one slipped by me 'cuz I'm no early Bronco expert. And, because it looks so original. Nicely done @Flintknapper .
It IS a 'cut' Bronco and has factory wheels but they are the 16" optional wheels not the 15" standard.

It has some other alterations as well (4 wheel disc brakes, NP435 four speed, lockers front and rear, 23 gal fuel tank, etc). I've owned this one for 40 years now.
 
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NCL4701

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This thread has likely drifted too far for a response to the OP’s original question to be useful but here goes anyway…

I have experienced “bunny hop” on my L due to rough ground or operator error (such as lurching forward due to my error/foot slipping and then over reaction causing opposite lurch). Regardless the cause, if I (the operator) am getting knocked about, it can result in a vicious cycle of the HST pedal also being knocked about which causes me to be knocked about further which causes the HST pedal to be knocked about further and on and on and on… Thus the vicious cycle of “bunny hop”. It’s much easier to have this cycle happen if you have your whole foot on the pedal. Once it starts the only way I know to stop it is remove foot from HST pedal. Pause briefly to allow operator and the tractor to come to a complete stop, then try again.

Obviously, this isn’t exactly common and I had more problems with this when I first started operating the tractor than I do now, but it can happen.

If any concern the above might be part or all of the problem, use cruise if you can. Looking at the pic of your tractor it appears to have a mechanical cruise, same as mine. It’s the lever with the orange tip beside your left hip as you sit in the operator seat. It’s a quite low tech thing that mechanically holds the HST pedal in a fixed position. Move it forward to engage and increase speed. With it engaged, you can stop by either moving the lever backward or hitting the brakes.
 
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