Checking shocks (& are they still bad after rebuild?)

D

Drwe

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Nov 28, 2021
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So my big rear shock is definitely in need of a rebuild, is there a way to test the small rear shock without taking the skid off the sled?
My sled has the aluminum (I assume rebuildable) shocks.

So, I'm looking to probably get both rear shocks rebuilt I'm quite sure the front shocks are still good but I'm wondering how I can tell for sure, what should I look for, or what measurements should I take to confirm?

I would be happy to simply remove the skid and pull the shocks off to avoid paying shop labour costs for that part but the truth is that it was pretty difficult to install the rear skid even with the help of two buddies. I'm not sure if there is a trick to getting it bolted into the tunnel, we did front bolts first, then rear then middle which were very difficult to line up.

I do see a small part on the rod on the big rear shock which has a rust "bubble" maybe the size of a dime, maybe an inch from the end of the rod, would that make the whole shock toast needing to be replaced? If for some reason I was wanting to replace the rear shock what are some good economical options here in Ontario?

A small side note, I also noticed the cap on the coolant reservoir seems fairly loose, as I understand it there is a brass pressure relief valve on the bottom of the cap which connects to the small maybe 4" long hose on the top, however I don't see the cap holding much pressure at all before coming off or leaking. Should I just replace the cap with a new (tighter?) one?
 

it can be a pain but you can pull the shocks with the skid in the sled.

for your skid install, i install how you do but i use a trick i found on here. i use a ratchet strap to compress the spring on the rear shock enough to put the bolts in. usually do it by myself unless i am teaching someone how to do it.

i have used shock tec here in ontario. depending where you are, there is a local guy in dowling area that does them as well. have not used him yet.
 
Maim said:
it can be a pain but you can pull the shocks with the skid in the sled.

for your skid install, i install how you do but i use a trick i found on here. i use a ratchet strap to compress the spring on the rear shock enough to put the bolts in. usually do it by myself unless i am teaching someone how to do it.

i have used shock tec here in ontario. depending where you are, there is a local guy in dowling area that does them as well. have not used him yet.
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I will definitely try the ratchet strap next time, thanks. I'm not sure how I'd get much torque on the shock mounts especially the center shock.

I could possibly send them out to shock tec, will the most Yamaha dealers not rebuild shocks? Are the wolftech shocks are royal distributing bad to use, who makes them?

The rear shock is obviously bad, but how can I check the center one?
 
i usually get them rebuilt as a set. never had to check them individually.

most dealers now-a-days send the shocks out to get rebuilt/serviced.

never used the royal distributing ones myself as i have quite a few spares still floating around.

the ratchet strap, i usually try to get the hooks around the bolts that mount the shock and then tighten it down until the bolts line up on middle mount.
 
Maim said:
i usually get them rebuilt as a set. never had to check them individually.

most dealers now-a-days send the shocks out to get rebuilt/serviced.

never used the royal distributing ones myself as i have quite a few spares still floating around.

the ratchet strap, i usually try to get the hooks around the bolts that mount the shock and then tighten it down until the bolts line up on middle mount.
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Good point, I'll look to get them both rebuilt, I'll pull the skid tonight and get them off. Can I simply unthread the preload nut to get the springs off or do I need a spring compressor?
 
So I just got the rear shocks back from rebuild. I put them in the skid, skid back into the sled and absolutely no difference. The skid sits high but just sitting on it (150lbs) and the skid drops almost to the bottom leaving maybe 2 inches to the bottom. The skid does not rebound at all (same behavior as original). I can lift it all the way up and it will sit up until I put any weight on the sled. I checked all of the spring preloads dimensions before installing the skid and they are still at the factory setting. Was this a botched shock rebuild? Could it be weak coil springs? Should I just buy new shocks?
 
Yes, everything moves freely. How high should the rear bumper bar sit at on these sleds?

It's sitting really low but maybe it's normal for these machines I'm not sure. The gap in the control rods is all at the top and when I stand and bounce on the rear bumper it does articulate moving the gap towards the bottom but I don't think it bottoms out on the rubber bumpers. The control rod gap makes me think I need to soften the suspension and maybe the ride height is actually ok?

What is the easiest way to adjust the full rate adjuster? It's at the middle setting now but I can't get it to move up (or down).
 
depends on if it is long travel or short travel. remove all dollies before seeing if any adjustments are needed. regardless, the slot with the 3 lumps in it at one end of the shock (called fra ) should be in the middle. then you set the spring tension on that shock so that when someone your weight, or your weight on the seat, the transfer rods end up at 50/50 for the best ride. this style suspension never goes all the way to the top of its travel unless you lift the sled by the bumper unless the spring is set waayy too tight. it is ok to flip the sled on the side or support it by the rear when adjusting the shock but transfer rod measurements need to be done on ground with weight on.
 
Yes on a concrete garage floor. Is there a way to get the shocks out and back in without pulling the skid? It's been extremely hard to put the middle bolts in when installing the skid and I don't want to do it again. My shocks are the threaded type so I cant adjust them inside the machine.
 
i adjust the threaded type in the sled all the time. with the track off the ground or sled on its side, need to use a hammer and screw driver to get jam nut loose. you can then turn the spring to get the nut to adjust tighter if the threads are in good shape. if they are tight, i use a shock spanner wrench to adjust it when it gets tighter. you can use the screw driver and hammer as well. once desired transfer rod gap is reached, tighten the jam nut back up with the hammer and screw driver again.
 
Maim said:
i adjust the threaded type in the sled all the time. with the track off the ground or sled on its side, need to use a hammer and screw driver to get jam nut loose. you can then turn the spring to get the nut to adjust tighter if the threads are in good shape. if they are tight, i use a shock spanner wrench to adjust it when it gets tighter. you can use the screw driver and hammer as well. once desired transfer rod gap is reached, tighten the jam nut back up with the hammer and screw driver again.
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I just took the rear shock out now. It was easy after I loosened the bolts on the control rods. What gap should I be trying to set with my weight on the sled? If the whole gap was at the top how many turns should I try first one, two? maybe I'll put it in with the locknut loose as you say and see where it is happy.
 
Drwe said:
I just took the rear shock out now. It was easy after I loosened the bolts on the control rods. What gap should I be trying to set with my weight on the sled? If the whole gap was at the top how many turns should I try first one, two? maybe I'll put it in with the locknut loose as you say and see where it is happy.
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it all depends on riding position and weight. if gap is all at the top with you on sled, it is too tight. needs to be 50/50 to ride its best.
 
Although gas shocks do assist the springs to a degree, it is the springs that carry the weight and thus determine ride height. The shocks main purpose is to slow the travel in both directions based on the stack of shims (washers) on either side of the piston. Basically they vary in thickness and diameter which controls oil flow depending on speed and energy. The thinner the shim, the faster oil is allowed through. One side controls compression, the other rebound. To be fair there is way more to it than that, but that is the basics.

Like others said, you either do not have the right springs, or they are adjusted way too soft. With most suspensions you do want a certain percentage of set-in. Set-in is how far from full travel the sled returns to on it's own after you take weight off of it. This is a starting point only IMO. You then should adjust with your full riding weight on the sled. Yamaha specs where to set ride height based on the average expected rider and riding style. It is still a mystery to me how they derive this as you generally will want to tune further once you ride it, but at least it gives you a starting point.
 
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