Lazy Bastard's custom rear suspension

LB, I seem to remember a post about your rear suspension where you stated that you extended the length of the rear arms to arrive at 14.5" of travel. You also state in your avatar that you have solved track tension problems. How was that accomplished? Have you posted any pictures and if not would you please? I am about to start a modified rear suspension project for my 03 and am considering going to a cat rear arm with torque sensing links and torsion springs. I will start out with the bolt that passes thru both rails in front of the arm for one way coupling and ditch the control rods. I think the front arm spring shock combo could be made to work as good as anything out there. It would be even better if I could borrow your idea and extend the front arm and reduce the approach angle as you have done. What do you think?

Ok, the big problem with track tensioning on extensions is when your objective is to reduce the approach angle. Absolutely critical is that the radius of the track matches the radius of the main-arm and is somewhere in the middle of the control rods. Problem you face with such things as relocations is that you increase the radius of the track without increasing the radius of the arms, so when the suspension compresses, the track tightens SEVERELY, so a simple relocation is NOT sufficient.

What I did with my suspension is quite extensive.
1) all arms extended by exactly 4 inches. That includes the main-arm (w-arm), back arm, and lower control rods (because they're easier and safer to extend than uppers).
2) moved the rubber bumpers in the middle of the rails back by 3.5 inches.
3) 7.5 inch rail extensions,
4) New drop brackets 7.5 inches back from original position, mounting hole slightly lower in order to provide clearance for rear heat exchanger,
5) Center shock mounting bracket straight back by 7.5 inches.
6) Middle (small) wheels moved back to next available set of holes to provide clearance for the back-arm - original mounting point for the back arm.
7) New mounting holes for back arm and lower control rods 7.5 inches (must be perfect measurement for the control rods) from original positions.

Now to perform the extensions of the arms, you actually need to cut the original square pipe out of it and replace it with new, longer 1" x 1". For the control rods its easy, just find a piece of steel pipe that has a curvature that matches the curve of the lower control rod (hint: 2"), split it lengthwise, hacksaw the lower control rods in half, and weld the two parts of the control rods onto the split pipe.

You'll note from the pictures that I've got the whole thing tied down pretty far, limiting the stroke. At full stroke, it will give 14.5" travel, but at the original approach angle. Strapped down it gives a reduced approach angle. I've got a whole bunch of plastic washers for the control rods and I intend to adjust how far down I keep it until I like it. Tied lower with the back bolt in lower positions on the drop plates will give better deep snow performance but less stroke depth, higher on the drop plates and more stroke should trench worse in deep snow, but offer a cooshier ride. I've never been much for a cooshy ride.

Looks pretty sweet L.B. Have you had a chance to even try it out yet?

How long do you figure it took to fabricate everything?

As you stated about the track tensioning as it compresses, What are you going to set the track tension / deflection at?

Do you think it will ratchet when you are at low speeds going to WOT?

I like what you've done, you got me thinking about doing something like that to my Warrior. You will be the test set up for those that follow.

I have not yet had the chance to test it out.. summer project and the snow isn't due for another couple of months.

Didn't take too long to fabricate, though the job did take a while. I was in no hurry, so I paced myself and was very careful about the measurements. Probably if I put all the thinking and building time together, it would be about a full week from morning to night, though only about 6 or 8 hours playing with the machines. Now that the thinking part is done, I could reproduce it in about 10 hours of work.

I plan on setting the track tension a bit looser than stock and seeing how it works. I doubt that it'll ratchet at all. My experience with the relocation kit is that it only ratcheted when the track was SEVERELY loose (ie dangling 2.5" off the rails so that the suspension would actually work). It also ratcheted after the W-arm broke no matter how tight the track was set.

Nice work LB. If I understand, by extending the arms you would raise the ride height of the sled. This alone might actually worsen the approach angle. You have countered this by cranking down the front limiter straps and reducing the lower control rod gap which causes the suspension to rotate up and back which reduces the approach angle. The only downside I can see is that the suspension will have more leverage on the shocks and you may find it too soft as is. This of course can be easily compensated for.

Its compensated by increasing the preloads. I'll have to figure out how that works out after I get to try it.

Tried and its good. With the extra leverage its a little soft and bottoms a little too easily, going to start playing with springs and shocks now.

Have the track HANGING LOOSE and it never ratchets AT ALL.

I see you have some earlier generation cast wheels. What is behind the choice?

why arent those rear wheels polished????

Those wheels would be difficult to polish. Maybe have them chromed instead.

they could be 7.5in. vs. stock 7in.

144 hartman kit

just finished my 03 144 hartman kit with the relocation brackets the other night,looks awesome,havent tried sled yet,my question is about the rear suspension brackets,i see you have 3 different holes,can i drill different holes and move just the rear bolts to lower ride height or would i have to do the middle one also to keep the geometry correct,i dont think i'll like the seat quite that high,i also noticed my track is rubbing the back top of the rear shock spring and mount a little bit,let me know what you think about this ....thanks

impalapower said:

I see you have some earlier generation cast wheels. What is behind the choice?

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Same size, not plastic, bearings can be changed, rubber on outside. They are the exact wheels that are on Exciter 570. I picked those exact ones because I compared the wheels on my *spare* sled and they were good.

BETHEVIPER said:

why arent those rear wheels polished????

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Because I haven't sent them in to cubby yet.

grader said:

they could be 7.5in. vs. stock 7in.

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I went with the same size 7". Going bigger REALLY doesn't make any difference, particularly since the slide doesn't go that far back.