Any idea why my Rear Shock Bolt bends in the middle?

[RangerRick]

Well, I increased the spring tension by 6 turns, it still bottoms out on very rough surface, as in wash board gravel roads. Marcus's instructions say if you do more than 4 turns you may need a different spring, contact him. Well that is no longer an option. So for now, I am putting back on the stock spring, then will look to see if there is any info on his spring, I'm sure he purchased them from a supplier. The stock spring is bigger and 2 stage. What a difference in these two springs, no wonder his shock bottoms out.

 

[BajaRon]

That is a very short spring. Inspect the spring and it should have some numbers and manufacturer identification on it. Most quality springs have the rate, length, and diameter displayed somewhere on the spring. You don't have to stick with the length. I would be extremely tempted to go with a longer spring. You certainly have the shock body to accomodate it. The shorter the spring, the harsher the ride. A longer spring will give you a nicer ride. A longer spring will require a relatively higher spring rate. But if you are bottoming out, you should up the spring rate anyway.

I would remove the spring first before purchasing another one. This way you can test the shock to see if it is still servicable. No use buying a new spring for a bad shock.

You have discovered the root of your problem. The first step towards success!

 

[RangerRick]

Thanks Ron. here is what's on the spring, and I see he used Bilstein.

 

[BajaRon]

Very good! That's an Eibach spring. They make some of the best springs in the industry. Here is what these numbers mean.

Linear Main Spring - Dia. 2.25 in | Len: 6.00 in | Rate: 500 lbs/in​

Linear simply means it is a single rate spring. The OEM spring is progressive (weaker in the tight coils getting stronger in the more spaced out coils). As with everything, there are advantages and disadvantages with each.

With a diameter of 2.25 inches you have all the information needed to get a ballpark idea of where you need to go with this.

Again, check the shock itself to see if it is worthy of a new spring rate before you do anything more.

 

[RangerRick]

Thanks Again Ron, I think the shock is fine. I have removed the spring, and the shock is fully extended and there is no way I can shove it. I'm impressed that there is even a roller bearing assembly on each end of the spring, as shown in the picture. I will grease these back up as I have cleaned them off. Waiting to hear opinions of what spring to replace this with. Sounds like longer for sure.

 

[BajaRon]

Thanks Again Ron, I think the shock is fine. I have removed the spring, and the shock is fully extended and there is no way I can shove it. I'm impressed that there is even a roller bearing assembly on each end of the spring, as shown in the picture. I will grease these back up as I have cleaned them off. Waiting to hear opinions of what spring to replace this with. Sounds like longer for sure.

View attachment 254149

I would talk to Eibach and get their professional opinion as to where you need to go from here. Glad to hear that the shock is in good condition.

 

[RangerRick]

I sent an e-mail to their Tech support, so

 

[Mikey]

Are you able to adjust the damping remotely from the outside of that shock? I still think the damping in that shock is not set right for you! Just my 2 cents! Springs help carry the load and gives you ride height the damping and pressure in the shock gives you the squash and restriction from bottoming out! That's my way of thinking, correct me if I am wrong Ron!

 

[Little Blue]

That would be correct about the spring. The Shock is a little bit different. I would need to carefully look over the shock. But I will defer this to Baja Ron.

Next Question please.

 

[BajaRon]

I want to be clear that I do not consider myself a 'Shock Expert', because I am not. I'm just knowlegable enough to be dangerous! If I can point you in the right direction, then I feel that I've done good here.

I believe that this is your shock (Pictured). It has a dampening dial (indicated). And it should have markings to tell you the + or - directions with clicks to give you orientation. I was not able to find the total number of clicks available, so I would turn it in the (-) direction and count the clicks to stop. Then do the same in the (+) direction to stop. Do not force it in either direction. You will feel added resistance at the stop, so quit when you get there. That will give you the total spread number of clicks (adjustment). This will tell you where you were on the full scale with the original setting.

I agree with Mikey and Little Blue that increasing the dampening may be enough. Especially if you were sitting at the lower end of the scale. You would need to experiment with this setting combined with the zip tie application. You might be able to get away without changing springs. Though for the ease and price, it might be an interesting experience to do so.

I hope Eibach responds with suggestions. That will be interesting. They may be reluctant to go to a longer spring, simply wanting to stay with the original design. Kind of a CYA thing. Who knows. Hopefully, that shoe drops soon.

 

[CrazyCooter]

I know everyone is trying to be helpful, but SOOOOO much misinformation here! I'm all about tech and learning, so lets put these misnomers to rest so that it won't keep getting regurgitated in our echo Spyder chamber?

The length of the spring has zero effect on the ride or rate. Its already been pointed out that the installed spring is a linear rate, so unless it is too long and binding at full compression OR unloading and unseating at full droop, that isn't your issue. There is no difference in the rate between a longer/shorter spring. The block height of your installed spring is 2.46" so you have 3.54" of available compression travel before it binds. IF your total shock stroke is only 2.5", that leaves room for 1.04" of preload, but I wouldn't push it that far. Just do the math to see IF the spring is binding. IF the spring has enough travel in the shorter configuration, it's lighter and therefore marginally cheaper/better overall?

To expand on the spring rate thing... It is common practice in the off road world to run springs WAY over length so that they can install a lighter spring rate, then dial in A LOT of preload. This nets the desired vehicle ride height, a lower ride frequency, slower ramp up of spring rate, while stuffing the wheel quicker into a hole (due to higher wheel rate at droop) after a bump event, so that the tire maintains traction to control the vehicle and keep putting power down. Think miles of 3' deep whoops where the tires just move up/down nonstop. The downside is this can introduce unwanted body roll, acceleration squat, and braking dive. This is similar in theory to how BajaRon's JRI's are configured? I'd quote the numbers between JRI/BajaRon's and Elka for comparison, but the numbers are no longer shared for the JRI's. From memory, JRI's have a much lighter rate than Elka, but this makes sense when Ron is setting them up with his complementing sway bars kits for a more compliant ride and controlled roll. Now keep in mind I HAVE NOT sampled Ron's shocks, but we do have his "Ultra Bar" on the RT. So I guess it's speculative, but I have 35 years in the suspension industry and can imagine the scenario. Because of the bar, I opted to drop one front spring rate from what Elka supplied.

As far as the actual rate is concerned, I would guess that a 500# would be in the ballpark, considering you don't have the aux bag. I don't own an F3, but IF the motion ratio of the rear suspension is the same as the RT (mounting points and swing arm length), you are right where I would think is good. I felt a 475# resulted in a ride frequency that was too low for our taste, even with the air bag active. I swapped it to a 600# and it's MUCH better for the heavier RT that we run loaded most of the time, but possibly a little too "sporty" for 1-up riding if you want a marshmallow ride like stock. It's awesome for traveling with a light load or even 2-up once the bag compensates. Eibach probably isn't going to help you decide. They don't offer off the shelf Spyder applications.

What you really need to do is put in a new bolt, reinstall everythong, and take static and rider sag measurements... There's lots of tutorials on the net. Then you will have an idea of what you need. Yours is easy without having to deal with the air bag.

Can you post up a pic of the lower shock mounting hardware? The OEM shock had one full length steel sleeve with plastic spacers over the top on each side to keep it centered/sandwiched into the swingarm mount? If Marcus just supplied some spacers to stack the width, this is why your bolt is bending. FYI... You could never bend that bolt upward by jacking under it unless the bike weighed 1000's of lbs.

You might also want to add an outer shock protector sleeve before you reinstall, to keep the grit from blasting the shaft and force feeding the seal pack. Cheap insurance on ScAmazon.

Anyway that was a lot...

 

[RangerRick]

Thanks CrazyCooter, for all the info. Yes Marcus put two sleeves in the kit, so there is not a one piece solid sleeve like stock. Here is the reply back from Eibach.

Unfortunately we are unable to specify a spring rate as we have no data on your Can Am, but the spring you have is a 500 lb/in spring rate. You may have to buy a couple of spring rates and see what works best for you. You probably need at least a 10% increase in spring rate, possibly more. We do have 550's, 575's and 600's in stock, the part numbers are listed below and they are $80 each. The 550 would be a 10% increase in rate, the 575 would be a 15% increase in spring rate and the 600 would be a 20% increase in spring rate.

0600.225.0550​

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0600.225.0575​

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0600.225.0600​

- Team Eibach

The following is from the manual included, by Marcus.

DAMPING ADJUSTER: Allows "stiffer or Softer ride". 72 clicks of total adjustment. Set out at 45 clicks from the stiffest setting

 

[CrazyCooter]

At first look, my eye is drawn the load being placed in the center of the bolt/shock eye with that 2pc spacer setup, but it's not like the net is littered with broken shock bolt reports? You might consider boring the spacers to the ID of the shock eye, drilling out your mounting bracket on the bike, and installing a larger bolt. Are the bushings damaged/worn in a manner where they can't pinch properly?

OE bolt diameter is 10mm, yes? What is the shock eye bore? The suggestion to swap out a grade 8 bolt would be a bad idea in this application. It would likely break instead of bend, leaving you on the side of the road.

Are you actually bottoming or this an assumption because of the bolt bending?

Another consideration, but I doubt this is your issue... The damping during high shaft speed moments (Example: hitting a square edged pothole at 65mph) is so high that the shaft could be effectively locked up. Without putting the shock on a dyno to test, you wouldn't know. Even though Marcus may have been considered a poor business man in my opinion, I believe he is very knowledgeable, having being in the business for some time. That said... he was selling a new "never set up" CTW shock dyno on ebay at the end, so was that a second dyno, or was he sending this stuff out unverified? Now I don't currently own a dyno, but I do own the vehicles that I send out tuned shocks for, and I have 60K miles of seat time. Marcus did not ride a Spyder?

I wouldn't screw with the spring rate for now. I think 500# is near your sweet spot.

What is the stroke on that shock? Slide up the foam bumper and measure between the seal head and the flat under the bumper. Also, stroke the shock by hand. Are there any air bubbles, dead spots, or binding? Or is it smooth and restrictive in a linear fashion?

That adjuster knob is a "Bi-Directional" bleed. It's just a controlled leak around the piston, so it affects both compression and rebound at the same time, assuming yours is the same as what Marcus was going to sell me. Some shocks have a one way check valve where the bleed only flows in one direction too. Marcus told me it was bi-directional.

So I'll attach a pic of my RT's OEM mounting... It's honestly pretty ghetto! The Canyon Red Rock is much worse because it has play in it even though the shock is of WAY higher quality. I have yet to tear it down to see what can be done to improve it.

Note the 1pc tube that carries all of the load, spacers keep it centered, and the bolts only job is to clamp it within the lower mount!? With your current setup, he created a bending point in the center where the bushings meet, since there's not much meat to clamp there.

 

[RangerRick]

Thanks CrazyCooter So should I crank up the damping beyond the 45 clicks that it is set at from the max setting?

 

[CrazyCooter]

Thanks CrazyCooter. So should I crank up the damping beyond the 45 clicks that it is set at from the max setting?

That's a trick question... Why do you think you need more damping? Are you bottoming out? If so, is your shock healthy? See the stoke test in my post above.

 

[RangerRick]

Yes, it bottoms out. I have put a zip tie around the shaft and shoved it up against the bottom of the shock and it ends up being shoved down onto the rubber stop. I have it dis-assembled, the spring is off as in the picture, and I cannot push the piston in by hand. There is 2 3/4 inches of travel. I have stock shock back on there for now, or maybe for ever...

 

[CrazyCooter]

If it bottoms and the shock feels healthy, then yes... add some more damping with the clicker.

You can go full tight and back off as needed to your liking for one method, or you could add 3-5 clicks at a time until it feels right. I like to move at least 3 clicks at a time, so that you can feel the change... if it was too much, then back it off 1-2 clicks until it feels right to you.

With that measurement of 2.75", you can run up to .75" of spring preload. Any more than that, and the spring will bind. If you need more preload AND your sag is within range, you should get a longer spring.

Maybe if you were slamming onto the bump stop, that was what has been bending your bolt. I still think that spacer setup is not the best design, but it's what you own. Maybe with more control/not bottoming hard, it wont bend again?

 

[RangerRick]

Thanks for more ideas/info