[WildDoktor]

I've installed 1.0kg/mm sonic springs in my 04 Vee. But I cannot get my sag set correctly; there's too much sag even with the preload adjusters screwed all the way in. And, my forks use all their travel with even "mild" forest service road riding. (I put zip ties on my forks to measure that.)

I only weigh like 202lbs, so it's not like I'm an overly huge guy; but I do ride as aggressively as possible, as often as possible!

Will longer preload spacers help this? Or do I need even stiffer fork springs?

Also, I have 130mm raising links in the back; which raises the rear 1.125" higher than stock. I'm not sure if that needs to be taken into consideration here?

 

[RichDesmond]

The 1.0s are plenty of spring for most people your weight or even 30-40lbs heavier.
What are your sag numbers?

How did you set your oil level, and what did you set it to?

 

[dravnx]

Oil won't affect sag. If you have too much sag, you have the wrong springs. Any chance they sent you the wrong springs?

 

[RichDesmond]

Oil level won't affect sag* but the amount of oil does affect the progressivity of the overall spring rate.

*Actually it does, but it's a tiny factor and can be ignored.

 

[Big Boy]

@ 265lbs, I used 1.1 kg springs and 14 wt oil for the forks on my ZRX1200. Worked beautifully!!!

 

[oldjeep]

The 1.0s are plenty of spring for most people your weight or even 30-40lbs heavier.
What are your sag numbers?

How did you set your oil level, and what did you set it to?

And when you set the oil level did you do it with the springs in or out?

 

[RichDesmond]

And when you set the oil level did you do it with the springs in or out?

Springs and spacer removed, fork fully compressed. Measure the distance from the top of the tube down to the surface of the oil. IOW, you're measuring the air gap.

 

[oldjeep]

Springs and spacer removed, fork fully compressed. Measure the distance from the top of the tube down to the surface of the oil. IOW, you're measuring the air gap.

Yup - I was wondering if he did that
Also need to make sure the cartridge is fully bled out

 

[WildDoktor]

Thanks so far guys!

• Yep; 1.0 should be plenty for me; not sure why they aren't holding me and the bike up correctly.
• The sonic springs box has a "1.0" in marker on the outside of the box, so they should be the correct springs.
• I can't remember the sag setting at the moment; it's been a while and I'm at work with no bike here. Will reply with the number when I can.
• I'm running 7.5w oil, 130mm air gap. I set the air gap like Rich mentioned: Springs and spacer removed, fork fully compressed. Measure the distance from the top of the tube down to the surface of the oil. I started with the Suzuki recommended air gap but there was excessive brake dive; so I added a little at a time. It's "better", but still dives too much for my liking.
• I also measured the spacers according to Sonic Springs I think at one point that page recommended more like 1 1/4" for adventure bikes (rather than 3/4" for sport bikes), but I may be remembering that wrong. At the time I replaced the springs, I made sure the spacer measurement was correct according to whatever I was reading at the time. But now, of course, I can't remember what the actual measurement is.

 

[RichDesmond]

Static preload should be about 3/4" on the Stroms. That's measured with the adjuster in the middle.
Overall, it sounds like you're setup correctly. If you were at the recommeded 150mm oil level I was going to suggest 130mm. You can try 115mm and see how that is.
On the "bottoming". The ideal is to use up all the travel, but just barely. The zip tie indicates the first part, but how does the bike feel? Are you getting harshness on those dirt roads?
Keep in mind that it's not a dirt bike, it's a 500+lb street bike with a cosmetic 1" lift kit.

 

[Jimding]

If the sag isn't right, something's wrong. Either the spacer is too short, or the springs are not what they are marked. Might compare the length of the new springs and the wire diameter vs. the OEM springs, see if they're in the same ballpark. Could be they sent you the wrong springs. Sag is a relatively simple measurement. If the springs are compressing too far, that needs to be investigated. If nothing else, need to add spacer length until the preload is right in order to hit the proper sag. Obviously limits as to how far you can go without binding the coils, of course. I'd start out by talking to the supplier, verify recommended spacer length.

 

[WildDoktor]

Static preload should be about 3/4" on the Stroms. That's measured with the adjuster in the middle.
Overall, it sounds like you're setup correctly. If you were at the recommeded 150mm oil level I was going to suggest 130mm. You can try 115mm and see how that is.
On the "bottoming". The ideal is to use up all the travel, but just barely. The zip tie indicates the first part, but how does the bike feel? Are you getting harshness on those dirt roads?
Keep in mind that it's not a dirt bike, it's a 500+lb street bike with a cosmetic 1" lift kit.

Thanks Rich; I will check for sure what my preload spacer measurment is, and what my sag is. Now that you mention it, I'm not getting a ton of harshness on the dirt roads from the front end...just keep seeing that zip-tie up at the top of the suspension travel after every single ride...even my commute (12 miles of mostly freeway). As for the excess dive, I didn't know I could go "down" (up) to 115mm air gap, I'll definately try that. I do have 2 jugs of 15w oil; I suppose starting over with that weight oil and a 130mm air gap would be the next thing to try after that. Hey wait; I have a Shinko 705 on the front, so this MUST be a dirt bike, right???

If the sag isn't right, something's wrong. Either the spacer is too short, or the springs are not what they are marked. Might compare the length of the new springs and the wire diameter vs. the OEM springs, see if they're in the same ballpark. Could be they sent you the wrong springs. Sag is a relatively simple measurement. If the springs are compressing too far, that needs to be investigated. If nothing else, need to add spacer length until the preload is right in order to hit the proper sag. Obviously limits as to how far you can go without binding the coils, of course. I'd start out by talking to the supplier, verify recommended spacer length.

Good points; I'll get my sag measurements soon and see if they're correct or not. Maybe they are correct, and the bottoming out is simply me out-riding the suspension. I'll probably try a slightly longer spacer if none of the above works out.

 

[RichDesmond]

Thanks Rich; I will check for sure what my preload spacer measurment is, and what my sag is. Now that you mention it, I'm not getting a ton of harshness on the dirt roads from the front end...just keep seeing that zip-tie up at the top of the suspension travel after every single ride...even my commute (12 miles of mostly freeway). As for the excess dive, I didn't know I could go "down" (up) to 115mm air gap, I'll definately try that. I do have 2 jugs of 15w oil; I suppose starting over with that weight oil and a 130mm air gap would be the next thing to try after that. Hey wait; I have a Shinko 705 on the front, so this MUST be a dirt bike, right???

Um, sure, if you say so...

I wouldn't go all the way to 15w, but 10w is a viable option. Or just use that 15w to do the top off to 115mm.

Good points; I'll get my sag measurements soon and see if they're correct or not. Maybe they are correct, and the bottoming out is simply me out-riding the suspension. I'll probably try a slightly longer spacer if none of the above works out.

I usually recommend 40mm of sag on the Stroms, but you could try 35mm. I wouldn't do any less than that. The spring should have a 1.0 etched on the ground flat on the end of the spring. It's only on one end, so Murphy being Murphy, you probably have the number down on both.

 

[Jimding]

Might set the sag a little 'tall' with the preload adjuster all in, and use that setting for dirt play. You do know you can mix fork oil weights to get intermediate values, right?

I suspect without a complete fork change (and more suspension travel), not gonna get real 'dirt bike' performance from the supension. It is a heavy bike, and you hammer it hard enough, it's gonna bottom. Set it hard enough not to, and rough pavement will hammer you.

 

[WildDoktor]

Ah...maybe it was the sag settings I remember reading about that were slightly different, and not the spacer length. That sounds more like it. I'm now curious to see what the measurement is now!

The weight designation being etched on the spring is GOLD info, thank you! And yes...they're probably both in with that etching at the bottom of the fork.

I did use the 15w to top up each from 150 to 130; I'll do it again to 115 and see if that helps the dive.

Yep; I know about mixing oil weights...I wanted to try 7.5w with my new 1.0 springs, but couldn't find any for sale at the time...so I mixed 5w and 10w evenly.

I'm just kidding about it being a dirt bike. I mean, I ride it like one, but I know for sure it isn't one. And I was reminded of that in no uncertain terms a couple weeks ago when it fell over, downhill. Yeah...like my step dad used to say, it took "6 men and a monster" to pick the thing up!

 

[Spec]

Suspension (hydraulic) oil isn't rated/certified for viscosity like motor oil. One companies 10wt could be another's 15.

Here's a WIKI that goes into detail

Suspension Fluid

 

[WildDoktor]

Sonic Springs

So could the part on this page about spacers be interpreted as saying "with the front wheel off the ground, so the forks are fully extended, if you remove the fork cap and the spring pushes the cap up, the part of the cap that sits on the top of the fork should be three quarters of an inch higher than the top of the fork." ?

If that's a good interpretation, then my spacers are too short, as mine only sits a little over a quarter of an inch above the top of the fork tube in that configuration. Thoughts?

Sent from my SM-N920V using Tapatalk

 

[baroquenride]

I've installed 1.0kg/mm sonic springs in my 04 Vee. But I cannot get my sag set correctly; there's too much sag even with the preload adjusters screwed all the way in. And, my forks use all their travel with even "mild" forest service road riding. (I put zip ties on my forks to measure that.)

I only weigh like 202lbs, so it's not like I'm an overly huge guy; but I do ride as aggressively as possible, as often as possible!

Will longer preload spacers help this? Or do I need even stiffer fork springs?

Also, I have 130mm raising links in the back; which raises the rear 1.125" higher than stock. I'm not sure if that needs to be taken into consideration here?

Your last paragraph is the problem- take the raising links out as it's putting a lot more weight on the front forks causing them to use up all the stroke.

Sent from my Etch A Sketch

 

[Jimding]

The raising links increase the weight on the front tire only very slightly. Might have a bigger effect on brake dive, though.

If the supplier verifies that they are the right springs, then just keep making the spacers longer until the sag is correct.

 

[RichDesmond]

Sonic Springs

So could the part on this page about spacers be interpreted as saying "with the front wheel off the ground, so the forks are fully extended, if you remove the fork cap and the spring pushes the cap up, the part of the cap that sits on the top of the fork should be three quarters of an inch higher than the top of the fork." ?

If that's a good interpretation, then my spacers are too short, as mine only sits a little over a quarter of an inch above the top of the fork tube in that configuration. Thoughts?

Sent from my SM-N920V using Tapatalk

I think you're thinking about it correctly. The real point is that the spring needs to be compressed ~3/4" (20mm or so) with the fork cap installed. With adjustable caps, also with the adjuster in the middle of it's range.
If you have the adjuster sitting on the spacer, the distance between the top of the fork tube and the underside of the top of the fork cap (the part that sits against the top of the fork cap when it's screwed down) should be 3/4".

All of this though is a means of getting to the correct sag. so I'd start by measuring that. Just make sure you do it correctly, with a helper, etc... When I owned Sonic Spring customer provided sag measurements were the bane of my existence, very few people did it right.