Trailer Suspension

[Lakesailor]

I was concerned that when I delivered Slippy to her new owner at Ullswater I may have a bit of a teeth shattering ride, or to be more precise, Slippy would.
The trailer was a 2 wheel affair with Indespension-type units. I remembered having collected her from Coniston when I bought her the 8 mile, slow, journey with a stop to effect trailer repairs had been noticeable for the rather harsh jogging ride the trailer gave.
I put this down to the suspension units being harder than need be for the light boat (550Kgs).
The trailer hadn't been used for more than a year.
For the journey over Kirkstone Pass I determined to go slowly and to give Slippy an easy ride. In the event after a few miles the trailer ride improved considerably and there was no crashing at all.
Does the team think that this is due to the rubber in the units becoming softer as it was worked, bearing in mind it's been stood, unloaded, for 18 months?

 

[PeteCooper]

If when you bought her she had been sat on the trailer for a while it is possible that the suspension was compressed a certain amount, thereby reducing any further travel. When you loaded her up for the final trip (with you) the suspension had had chance to relax and was not so compressed to start with. As you know full well this is what happens with Mini suspension cones.

 

[halcyon]

May have been a simple thing like rust.

Brian

 

[Lakesailor]

No. Was on the water when I bought her and had been for a year. The trailer had been unloaded in each instance. I'm thinking the suspension movement itself softens the rubber from it's rather stiff resting state?

 

[Lakesailor]

I'm pretty sure rubber doesn't rust.

 

[VicS]

The Indespension units do tend to seize up if left standing, I guess it's rust, I always work mine free with a long lever in the end of the arm and wd 40 sprayed at both ends before I use it.

 

[Lakesailor]

I was thinking it was the rubber becoming more rigid. Then the use of it starts to soften it again. I am not sure if rusting of metal parts would affect the suspension movement.

 

[Blue5]

Had you checked the tyre pressure two years down the line

 

[Lakesailor]

I tried both. Hard to try transmitting more loads into the suspension to make it work, and lower to absorb the shocks rather than crashing the boat of the trailer.
Neither seemed to make a difference, but about 3-4 miles of a bumpy road softened the ride considerably.

 

[Kawasaki]

The swing arm that connects to the stub axle and at tother end goes into the toresion arm what sticks into the "Rubber bit" bounces along as yer go.
Fairly good bits of kit, these Indespension Units.
More like shock absorbers than suspension units really.
Minimal travel but a lot better than nowt!
As the bit that sticks into the rubber is in "torsion" ie twisting about a bit this way and that.
Friction is apparent.
Friction will create heat. Heat will "soften" the stuff the torsion bar is sat in and "soften" the ride.
If the units have been stood for a while the "rubber" will change properties a bit.
As you know with tralering summat, it,s all about balance, tyre pressures too.
Best to have the trailer tyres as low as is safe and possible.
Say again, they aint really suspension as We know it more like shock absorbers.
Sometimes too if the load aint heavy enough the little blighters bounce a bit more.
Rust? Lost on that one /forums/images/graemlins/confused.gif

 

[Lakesailor]

You've moved along the lines I was thinking on there. That's how it seemed it would have "freed off" to me.

 

[Kawasaki]

Yer needs to Know Yer Rubbers.
Especially when Yer have a stiff one! /forums/images/graemlins/wink.gif

 

[mainmarine]

could be that the torsion bar has become detached from the rubber it goes through and is moving move than originally.

 

[Lakesailor]

Wrong way around. It was too stiff at first and loosened off to become just right.

 

[oldharry]

Guess you have hard rubbers.

Things can get stiff if they are not used for a while. Once in action things warm up and the ride improves....

Why, what did you think I meant? /forums/images/graemlins/blush.gif