A few questions....

[Blue Dave]

You can adjust your preload (sit-in) easily by yourself by using a wire tie on your shock rod.

Simply tighten the wire tie around your shock rod and slide it against the shock with the rear of the sled lifted in the air on a stand. Then when you let the sled down and sit on it the wire tie will slide down the shock rod and stay at the point where it slid to.

Then you can measure the "sit-in" (how far the wire tie slid) without someone else trying to do it with a tape measure while you are sitting on the sled.

 

[BigMac]

You can adjust your preload (sit-in) easily by yourself by using a wire tie on your shock rod.

Simply tighten the wire tie around your shock rod and slide it against the shock with the rear of the sled lifted in the air on a stand. Then when you let the sled down and sit on it the wire tie will slide down the shock rod and stay at the point where it slid to.

Then you can measure the "sit-in" (how far the wire tie slid) without someone else trying to do it with a tape measure while you are sitting on the sled.

Great tip!

 

[Blue Dave]

I can not take full credit for the tip because I saw it in another posting last year when I set my sit-in. That is what is so great about TY, all of us helping each other and learning from each other!

I have learned so much from this site I am going to upgrade from a VIP to a lifetime member. I figure it is money well spent if I can help keep this site operating for as long as I am riding Yamaha sleds. (hopefully for at least another 25 years!)

 

[subaru2006]

Awesome tip but where to I go from there to set my sit in to 40mm?
I did some reading in th manual again hoping something would pop out at me but everytime I look at it and go to the sled it just doesnt make sense. I wish there was a basic setup to this suspension and you could fine tune it from there. Like a step by step what does what on this.

Subaru2006

You can adjust your preload (sit-in) easily by yourself by using a wire tie on your shock rod.

Simply tighten the wire tie around your shock rod and slide it against the shock with the rear of the sled lifted in the air on a stand. Then when you let the sled down and sit on it the wire tie will slide down the shock rod and stay at the point where it slid to.

Then you can measure the "sit-in" (how far the wire tie slid) without someone else trying to do it with a tape measure while you are sitting on the sled.

 

[BigMac]

Awesome tip but where to I go from there to set my sit in to 40mm?
I did some reading in th manual again hoping something would pop out at me but everytime I look at it and go to the sled it just doesnt make sense. I wish there was a basic setup to this suspension and you could fine tune it from there. Like a step by step what does what on this.

Subaru2006

You are measuring the amount of spring compression, so you need to measure the spring length with the sled unweighted at the rear, compared to its length with the rider (with gear on) sitting on the sled. That difference should be between 40-45 mm of compression. I did it by measuring the actual spring length with a tape measure (takes two people), Blue Dave mentioned it can be done by measuring the amount of travel of the shock rod -- same thing -- you're looking for the amount of shock travel for a given rider weight. If the spring is set too soft, it will travel too much to the point where it will bottom. It only makes sense that a sled suspension set for a 200 lb rider will be too harsh for a 120 lb woman, and too soft for a 240 lb man.

To adjust, you have to loosen the lock ring on the shock body, then turning the spring clockwise or counter-clockwise (that will turn the adjuster ring) to incease or decrease the preload on the spring. If the spring is adjusted too soft, you will bottom out a lot. If it's too hard, you'll have a harsh ride. I weigh about 190 with gear on. My Apex rode pretty harsh when I got it from the dealer, and I didn't like the ride or handling at all. After I adjusted the spring preload (and softened up the front suspension too) it was a night and day difference. Now, I can ride down the trail comfortably. If the trail is dead smooth, I decrease the damping with the electronic control. If it's a rough trail, I bump it up a few bars. Once the pereload is set correctly...THEN I could use the electronic damping adjustment to prevent bottoming. It is a very slick system. These sleds do come set up with a basic setting, but they can definitely be improved by fine-tuning the suspension to individual riders' weights.

I agree that the manuals aren't very helpful. They show absolute spring lengths, which still leaves you with a lot of guess work. By measuring the actual shock travel (either by amount of spring compression or by shock rod travel) weighted vs unweighted for a given rider and setting it to between 40-45 mm, you are actually custom tuning it for yourself.

Note that if you weigh more than about 220-225 lbs with gear (Yamaha says 240 lbs), you may need a heavier shock spring because you can't get that magic 40-45 mm unless you tighten the spring to the point where it's too short and interferes with shock pivoting. Those "big boy" springs are available from Pioneer Performance, among other places. Note that some posters have recommended that that monoshock spring be replaced with a Pioneer dual-rate spring anyway, or that the shock be re-valved to p[rovide more effective damping. I didn't find that to be necessary to get the sled to run better than any sled I've ever owned, but a lot of people swear by the revalving. Look at the Pioneer Performance website http://www.pioneerperformance.net/ for more info. Personally, I'd meticulously set up the suspension as recommended and ride it. It it still doesn't suit you, you can pull the shock in the off-season and send it to them for re-valving.

 

[Blue Dave]

In addition to setting the "sit-in" on the rear shock, I lowered my front end which also helped greatly.

To lower the front end, lift the front of the sled in the air and then spin the spring compression nuts on the shocks down until the springs are almost completely loose. Make sure both sides are adjusted the same (measure the threads).

When you set the sled back down on the ground you will notice that the A arms are more level and when you ride the sled I believe that you will agree that it handles much better.

 

[Len Todd]

Here is a good place to start. The Spring pre-load on the rear shock should be adjusted to match your fully dressed weight. If you are bottoming, then you may need to add pre-load, if you are not maxed out already. Actually, if you are maxed out, you may need to change springs to a heavier spring. But the guys tips above will help you get started.

 

[subaru2006]

Ok so I did the sit in check and this is what I got. With the sit in it was very close to 1 3/4" differnce. As for the transfer control rod it was set at the STD according to the "special wrench". The limiter strap is at the first hole on the top. I didnt check the damping stuff yet. The EC setting is set in the middle. So I was wondering if the sit in was fine. I checked the sit in with the pioneer thing they sent out with the revalve. (mine isnt revalveed) I found it on this site. They say 1 3/4" is the max sag? Should I do anything to mine?

Subaru2006

 

[BigMac]

1.75 inch = 44.45 mm. Sag is supposed to be between 40mm - 45mm. You're in that range so you should be good to go. Your damping setting won't affect sag - that's entirely determines by spring preload. If you wanted, or if you are still bottoming out, you could give your spring a little twist to decrease your sag a little - you have about 4 mm of shock travel to play with. I set mine at 40mm in case I gained weight or something . But if you're in that 40-45 mm sag zone, your EC damping adjustment ought to cover the bottoming. My approach is to set it as soft as possible. If the trail conditions get to the point where I bottom too much, I just click up the damping.