changing 8" tires to 13" tires.

[limitout]

Re: changing 8" tires to 13" tires.

No such thing as "normal" position... they are installed both over AND under on different trailers.... You can't possibly know that it isn't in the factory original position...

I have yet to see one single light weight 1500lb or less boat trailer sold with factory axles mounted above the springs

MOST trailer axles have camber built into them and installing them upside down can lead to tire wear problems... to correctly "flip" a trailer axle requires that spring perches be mounted on the top or bottom to allow the axle to mount in it's original attitude.

again you ONLY think in terms of what you are used to which is large big heavy boats with large heavy trailers so your point of reference and viewpoint reflects only that experience. while its true that MOST large heavy trailer axles have camber built into them, its also true that most light weight trailers do not and they do indeed have perfectly straight non cambered flat axles. cambered axles only show up when you start to get into the heavier class single axle trailers. when you shop for new straight axles they have them with or without camber depending on the axles weight class and the straight axles are designed to give you the choice to be mounted over or under the springs. I am surprised you didn't know all this.

I just counted... of the 9 trailers here on the property 2 have axles under the springs and 7 have axles over the springs. All are believed to be in factory original positions.

are they boat trailers or utility trailers? and what are the brand and weight class of those two trailers that have factory axles over the springs?

the OP still has his motor and trailer frame bottoming out (look at the ground clearance and not just the boat height) so while lifting the bunks is a good idea, flipping the axle is going to be a better step in getting him the safe ground clearance he needs. if he needs more clearance after that, then he should raise the bunks. either way the boat will be higher but my way the trailer frame wont still be dragging the ground on curbs and steep hills.

you have your opinion and I have mine. the OP has heard both and will do what he thinks is best for his own peace of mind.

 

[dockrat100]

Re: changing 8" tires to 13" tires.

My axle does have a camber built into it. If I flip it it will reverse the camber. The way it is currently, the center of the axle is slightly higher than the wheels, which should put the top of the tire "out" just a little from the bottom.


\-----/ Somewhat exaggerated, but like this, methinks.

 

[dockrat100]

Re: changing 8" tires to 13" tires.

I just measured from the rims, the top is nearly and inch farther apart than the bottom.

 

[limitout]

Re: changing 8" tires to 13" tires.

My axle does have a camber built into it. If I flip it it will reverse the camber. The way it is currently, the center of the axle is slightly higher than the wheels, which should put the top of the tire "out" just a little from the bottom.


\-----/ Somewhat exaggerated, but like this, methinks.

then you cant flip the axle so you should strongly consider replacing the axle with a straight axle or just replacing the whole trailer and sell the old one. you have no weight load pressing down to straighten out the axle so you are constantly riding with wheels that are untrue and will wear extremely fast

well unless it has just gotten bent somehow, it looks like you do have a cambered axle and that means it DEPENDS on a certain correct weight load to straighten the axle out so it rides straight and true.

putting everything we have discussed in this thread together, all into one list of things that are wrong or need to be fixed/ adjusted, looking at all that together, I think you would be better off selling that trailer as is and just get another trailer with a straight flat axle that comes ready to go and comes with no issues.

the idea of the camber is the weight would cause it to bend so by pre bending it the weight will bring it straight again. the problem with that system is if you don't have the expected weight load on it the camber actually forces the wheel out of alignment and they ride just like in your diagram and that isn't how it is supposed to ride.

 

[smokeonthewater]

Re: changing 8" tires to 13" tires.

why on earth would he be towing his trailer on curbs and hills so steep that the frame drug???

good grief... now you think his axle needs replaced because you think it shouldn't be cambered like 98% of all trailers?

so since his trailer is sooo light that it can't even flex it's axle it's gonna go destroy tires?

He "can't flip the axle"???? of course he can... just needs a couple spring perches, new ubolts, and new center pins.... but he doesn't NEED to flip it.


OP your axle is fine... unless you really do have tire and frame dragging problems and limitout managed to figure that out with psychic powers then all I would worry about is getting the rear of the trailer as close as possible to the rear of the boat AND getting the outboard supported in the raised position..... as for boat height, within reason, lower absolutely is better.

 

[dockrat100]

Re: changing 8" tires to 13" tires.

Should the camber be positive or negative? /---\ or \---/ ??

I have a plan to cheat the trailer length issue. If the camber is supposed up be negative, I can flip the axle without buying new hardware.

Currently, I have positive camber, \---/

Should it be negative?

 

[smokeonthewater]

Re: changing 8" tires to 13" tires.

no the camber is correct as is

 

[limitout]

Re: changing 8" tires to 13" tires.

when you press down on the axle with the expected weight load it bends the axle straight and the wheels will stand up from looking like this: \---/ to look like this: l --- l

that's why if you don't have the correct expected weight load on a cambered axle it stays looking like this: \---/ and doesn't ride correctly and wear tires unevenly even though it will still trailer just fine

 

[smokeonthewater]

Re: changing 8" tires to 13" tires.

uneven yes a little but not fast.... he'll likely get more miles out of a set of tires riding a little onto the outer edge than a heavier trailer on the same tires... he'll be absolutely fine