14' narrow track bouncing when empty. porpoising

[rerod]

Hello.

I found a 2000 14x7 kiefer "narrow track" enclosed trailer I made a excepted 3k offer on. Plans are to drive south a few hours on Thursday to look and buy it, but something has me concerned..

The owner said they replaced this trailer with a new aluma enclosed "because it tows better".. He said when the kiefer was towed empty or lightly loaded with their motor home bus, they had some bouncing which Iv heard people call "porpoising". How bad, or how much of the time it bounces I'm not sure.. But everyone inevitably has to tow empty and I would hate if the trailer bounced the entire time! He said it didn't bounce when loaded.

I remember one time towing my fully loaded 24' featherlite TH, I ran over some road that made it feel like we were jerking back and forth uncontrollably! It scared us but stopped after what seemed like forever but I thought the receiver might just tear off! That was the only time I experienced any bad towing and I don't want anything like that ever again.

What causes bouncing or porpoising with a short 14' enclosed with two 3500# torsion axles? Could it be that the 18 year old torsion axles are wore out even though it doesn't look to be riding low? Could it be as simple as tire pressure to high? Or ride attitude to low in front? I never needed a WD hitch with my 24' featherlite so I assumed I would not need one with this 14'.

Even though I really like this trailer mainly due to its narrow track design and one piece rounded roof. I'm not going to like driving so far for a trailer that bounces much of the way home, if that's the case. What do I do if it does bounce when I'm test pulling it?

Any suggestions or advice would be appreciated..

Thanks!

[deltabravo]

enblethen wrote:
Photo shows trailer has the wheels what seems to be back on the trailer.

All Cargo trailers are like that. Not a problem.

[mkirsch]

rerod wrote:
Thanks for the tip that 14' isn't long enough.. What brand is your narrow track mkirsch?

It is a 2004 United brand. Had it custom ordered because I was worried that an 8' wide trailer would be too hard to keep in between the lines, and I only had a half ton truck with 4.8L engine at the time. With my current truck I could have gotten a standard 8x16 trailer for about the same price, with double the usable area inside.

[rerod]

Bobbo wrote:
When I sold my tow dolly in 2010, I had someone who asked if I could hold it for him. I told him the first person at my door with cash got it. I won't hold it. Ticked him off, but I wasn't going to turn away money and was honest with him.

Yeah, I cant blame the owner but I was fuming the day I learned. I'll admit that if that trailer was that important to me, I should have sucked it up and made the miserable trip. I gambled that no one would offer more than 3k.

Grit dog wrote:
I'll still say, although you appear to be about 100% set in what you want and will not waiver, if your building something for the long haul, it doesn't make much sense to start with a 15-20 year old trailer. Especially in the rust belt.
Don't look at it as a % of new vs used cost look at total $ out the door.
$3k (if you can find it, or maybe you'll sit on the couch indefinitely until you find one) vs $5k for a trailer isn't much.
You'll start off with new bearings, brakes, tires, Jack, breakaway system, wiring, etc....a new trailer!
If you have to work on all that stuff or replace, you'll eat up that $2k mostly in money, or more in time too and still have an old trailer.
The 12 valve thing I get. Significant difference between that and newer trucks and the simplicity is a bonus. Even with the 12V though it's a point of diminishing returns.
But trailers are trailers. They haven't changed in 30 years. Certainly not for the worse. And your one experience with a leaky roof doesn't mean anything. If it leaks fix it, if it still leaks, you don't know how to fix a roof.

Thanks Grit dog

I will call MTI king back and ask about building the narrow track with the truck wheels because if they will, I will be way ahead instead of later buying 5200# 8 lug axles and four new wheels/tires.

Does anyone know if 5 lug hubs can be replaced with 8 lug hubs on a 3500# axle?

Second.. Ive read the center hole of the stock truck rim might not fit over the trailer hub? It sounds like I would have to buy aftermarket rims for the truck and trailer if I want them interchangeable.

[Grit_dog]

I'll still say, although you appear to be about 100% set in what you want and will not waiver, if your building something for the long haul, it doesn't make much sense to start with a 15-20 year old trailer. Especially in the rust belt.
Don't look at it as a % of new vs used cost look at total $ out the door.
$3k (if you can find it, or maybe you'll sit on the couch indefinitely until you find one) vs $5k for a trailer isn't much.
You'll start off with new bearings, brakes, tires, Jack, breakaway system, wiring, etc....a new trailer!
If you have to work on all that stuff or replace, you'll eat up that $2k mostly in money, or more in time too and still have an old trailer.
The 12 valve thing I get. Significant difference between that and newer trucks and the simplicity is a bonus. Even with the 12V though it's a point of diminishing returns.
But trailers are trailers. They haven't changed in 30 years. Certainly not for the worse. And your one experience with a leaky roof doesn't mean anything. If it leaks fix it, if it still leaks, you don't know how to fix a roof.

[Bobbo]

When I sold my tow dolly in 2010, I had someone who asked if I could hold it for him. I told him the first person at my door with cash got it. I won't hold it. Ticked him off, but I wasn't going to turn away money and was honest with him.

[Grit_dog]

Ok, so you’re planning on a real load in it and a fair amount permanent installed. Big axles won’t be as overkill as imagined.
Good luck with your search

[rerod]

mkirsch wrote:
To be fair, you flaked out on him first, not wanting to drive 2-1/2 hours to look at the trailer. You can't expect him to sit on it for a month until he gets up your way, only to have you look at the trailer and tell him you don't want it, after he's turned down several offers.

By the way, I do have the exact trailer you're looking for, and no it's not for sale. I started making the modifications you have listed. Shower, cabinet (for an eventual sink), place to sleep, etc.. Turned out 14' is just not big enough to fit everything in. I had to shuffle EVERYTHING around every time I wanted to use a different function of the trailer. Taking a shower required moving just about everything in the trailer. Sleeping required moving just about everything. I didn't even bother trying to cook.

The trailer I wanted on craigslist was listed to be 1 hour south in Iowa. But when I contacted him, turns out it was 2 1/2 south. I wasn't searching in Illinois, but that's were it was.
If you rode in my current truck you would understand why I didn't go with no AC. Whatever, its gone supposedly.

Thanks for the tip that 14' isn't long enough.. What brand is your narrow track mkirsch?

[parker_rowe]

mkirsch wrote:
To be fair, you flaked out on him first, not wanting to drive 2-1/2 hours to look at the trailer. You can't expect him to sit on it for a month until he gets up your way, only to have you look at the trailer and tell him you don't want it, after he's turned down several offers.

This is why I never make an offer until I've looked something over first, and I won't put up with someone that give me the runaround on something I'm selling. Come look at it, today, and bring cash. Otherwise I'm moving on to the next guy who says he can come look at it today, and is bringing cash. None of this "accepting" an offer from some guy who has never seen it, and probably won't ever show up.

Yep, unfortunately sellers have the same experience with "a mans word". Sellers say it's a done deal and never make it to pick up the item, more often than not. Can't turn down real cash in front of you.

It happens...frustrating sometimes when you can't get to the item you want fast enough, put just the way it goes.

[mkirsch]

To be fair, you flaked out on him first, not wanting to drive 2-1/2 hours to look at the trailer. You can't expect him to sit on it for a month until he gets up your way, only to have you look at the trailer and tell him you don't want it, after he's turned down several offers.

This is why I never make an offer until I've looked something over first, and I won't put up with someone that give me the runaround on something I'm selling. Come look at it, today, and bring cash. Otherwise I'm moving on to the next guy who says he can come look at it today, and is bringing cash. None of this "accepting" an offer from some guy who has never seen it, and probably won't ever show up.

By the way, I do have the exact trailer you're looking for, and no it's not for sale. I started making the modifications you have listed. Shower, cabinet (for an eventual sink), place to sleep, etc.. Turned out 14' is just not big enough to fit everything in. I had to shuffle EVERYTHING around every time I wanted to use a different function of the trailer. Taking a shower required moving just about everything in the trailer. Sleeping required moving just about everything. I didn't even bother trying to cook.

[rerod]

Grit dog wrote:
^ Yeah, that's considerably more than $3k for sure.
How much weight do you plan on hauling?
That's an awful small trailer for 5200lb axles, especially if you're concerned about how much it bounces around when empty. 5200lb springs come with those axles ya know.

Guess if you're searching for a unicorn trailer that rightly no one or very few would spec out, you may be looking for a while unless you spec your own.

You did mention going off road. Ground clearance on narrow tracks or inlines with recessed fenders inside have cr@p ground clearance. Deck overs, whle they sit a little higher, also sit a little higher. Way better ground clearance and no fenders or tires to rip off the side.
As far as matching your trucks lug size, id, why that has any bearing on your trailer. You're apparently buying a trailer for the long haul. You get lugs to match, what about tire size? You get a new truck, then what? You have a trailer with a gvw of over 10klbs, what difference does the extra 40-50lbs of a spare tire for the trailer make?

The owner emailed me that someone payed their 4k asking price but I call BS.. This, once again unfortunately, has renewed my faith in a mans word.
I put a 4" lift on my old feather lite and planned the same for this trailer but the axles will always be the lowest point and a enclosed deck over like a snowmobile trailer is to tall if its tall enough to walk into which most are not.

Weight? Im not sure. But after install a bathroom kitchen a/c heat etc, load a couple of 600# motorcycles, kayak, mountain bikes, tools, camping gear, 4 t105 batteries, generator, 100 gallons of water, solar panels, food for a week etc etc etc. It will be packed to the gills! It could easily be 4000# or more if I take two motorcycles. The matching wheels, which the off road trailer guys do all the time, is mainly to save space/weight with only one spare, but sounds like the 4.75" offset of the truck rim would be the problem because trailer rims have 0 offset unless I spec it.

I have $14k set aside for the trailer project, but I just cant get it started. I have another 14k set aside for a 4x4 12 valve 5 speed cummins to replace my last one which is also really hard to find.

[Grit_dog]

^ Yeah, that's considerably more than $3k for sure.
How much weight do you plan on hauling?
That's an awful small trailer for 5200lb axles, especially if you're concerned about how much it bounces around when empty. 5200lb springs come with those axles ya know.

Guess if you're searching for a unicorn trailer that rightly no one or very few would spec out, you may be looking for a while unless you spec your own.

You did mention going off road. Ground clearance on narrow tracks or inlines with recessed fenders inside have cr@p ground clearance. Deck overs, whle they sit a little higher, also sit a little higher. Way better ground clearance and no fenders or tires to rip off the side.
As far as matching your trucks lug size, id, why that has any bearing on your trailer. You're apparently buying a trailer for the long haul. You get lugs to match, what about tire size? You get a new truck, then what? You have a trailer with a gvw of over 10klbs, what difference does the extra 40-50lbs of a spare tire for the trailer make?

[rerod]

This is the second narrow track trailer that's been sold out from under me. Yes call me lazy for not driving 2 1/2 hour without AC after being promised it will be 1 hour away yesterday.

The search goes on.. But it feels like I just got kicked down low again

Whats funny is that the two links I posted were actually both diamond trailers. So diamond (Bendron Titan) and now King are the only ones..

[rerod]

Grit dog wrote:

May still be worth a call to King Trailers in Wausau.

I talked to Bud at King Trailers who quoted me $5k for a 7x16 narrow track with flat roof. They offer round roofs but where they place the seams these days, it isnt worth it imo.
And $600 extra for 16" radials and 5200# axles. The 16" wheels don't sound as attractive now because Bud said the offset of the rim would be different than my trucks.

[Turtle_n_Peeps]

As was said above, bounce and porpoising are two different things.

You said you have bounce so lets look at that.

Dolly's bounce when there is no load on them because they have no suspension and the tires act as such.

Small trailers do have suspension but they do the same thing as a tow dolly when there is no load in them because of high spring rates.

Two things you can do.

#1. Lower the air pressure on you tires so it will cushion the ride and act as a suspension component.

#2. Get some shocks on the trailer so the shocks will control the rebound. You will have to pick the correct ones. Ones with too much compression and you will be right back to bouncing all over the place again.

Good luck and happy travels.