# Dart 2 Preload Adjustment



## Jnthomps08 (Mar 22, 2010)

I was flipping through the owner's manual for my Dart 2 and I was reading the part about adjusting the preload for "sag". I knew the fork had this option, I had just never utilized it. 

The directions on how to do this seem incomplete. Im not sure exactly how to adjust the preload and I cant really tell a difference when its adjusted tighter or looser. Is it really necessary to have it dialed in? You have any advice on how to adjust it?

Thank you.


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## ataylor (Dec 28, 2009)

If you cant tell the difference between a high amount of preload and no/low preload your fork may be broken. Does the amount of sag change?


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## Jnthomps08 (Mar 22, 2010)

Yeah the sag does change but Im not sure how to adjust it for me... Does that make sense?


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## musky (Jul 21, 2007)

In general, you typically want about 20% of the forks full travel used as sag.
Basically, when you get on the bike,. the fork should compress some to compensate for the riders weight. Thats a 100mm fork I believe, so about 2 cm should do it!


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## Jnthomps08 (Mar 22, 2010)

So, have the fork on full travel and set on it and adjust that preload to move ~2cm (or do the zip tie thing in the manual) when I set on the bike? Well, thats alot simpler than I thought it was. 

Thanks.


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## musky (Jul 21, 2007)

I would say either method will work. If you think you have gone too far, just readjust it back.
I had the same fork at one time and didn't find adjusting did much. Glad you're having better luck.


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## mullen119 (Aug 30, 2009)

Its an 80mm fork I am pretty sure so sag should be 1.5cm. Dart 3 is 100mm


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## GFAthens (Sep 10, 2009)

My 09 Dart 2 is 100mm travel.


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## Brujo (Jan 21, 2010)

darts can be 80, 100, or 120 mm find out how long travel is and sag should be 20% of that


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## musky (Jul 21, 2007)

Brujo said:


> darts can be 80, 100, or 120 mm find out how long travel is and sag should be 20% of that


Correct!


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## GrayBeard Pirate (Dec 26, 2009)

Great thread...I will check out my Dart 3 to make sure I have the preload set appropriately.

Thanks!


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## AndrwSwitch (Nov 8, 2007)

Sag is just a starting point for adjusting the fork, IMHO. It's a good guideline, but forks are for riding and how it rides is what matters.

If you tend to bottom your fork out a lot when you're riding, you need more preload. If you bottom it out a lot and you're preloaded all the way, you need a stiffer spring. If the ride is harsh, try less preload. If with no pre-load, you never use your whole travel, you need a softer spring.

This fork has no rebound adjustment, so you may find you want to run it a little soft to keep it from bouncing back as hard after you go over things. Or it might be totally fine.


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## adrianmoisey (Jan 3, 2008)

AndrwSwitch said:


> This fork has no rebound adjustment, so you may find you want to run it a little soft to keep it from bouncing back as hard after you go over things. Or it might be totally fine.


My 2007 Dart 2 has a rebound adjustment at the bottom of it.


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## Jnthomps08 (Mar 22, 2010)

It has rebound adjustment on the bottom.


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## mullen119 (Aug 30, 2009)

Jnthomps08 said:


> It has rebound adjustment on the bottom.


 According to the the sram website, the dart1 has only a preload adjustment, the the dart2 has preload and a option for a lock out, and the dart3 has preload, external rebound, and lockout. I know my wifes 2008 dart 2 manual said the only way to control rebound was to change the oil weight.


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## adrianmoisey (Jan 3, 2008)

mullen119 said:


> According to the the sram website, the dart1 has only a preload adjustment, the the dart2 has preload and a option for a lock out, and the dart3 has preload, external rebound, and lockout. I know my wifes 2008 dart 2 manual said the only way to control rebound was to change the oil weight.


Strange, I double checked and mine definitely has the rebound adjuster. The shock is a lot older (2007) I have it on my Giant Alias (http://www2.giant-bicycles.com/en-AU/bikes/mountain/1131/28948/?collections_id=3).

The rebound adjuster is a little knob on the bottom of the fork which you can turn towards a little picture of a rabbit or a picture of a tortoise.


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## Jnthomps08 (Mar 22, 2010)

adrianmoisey said:


> The rebound adjuster is a little knob on the bottom of the fork which you can turn towards a little picture of a rabbit or a picture of a tortoise.


And Im looking at that knob on my Dart 2 that came on my new Fisher Marlin.


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## AndrwSwitch (Nov 8, 2007)

Awesome. Ignore the bit I said about messing with spring rate to help tune rebound.


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## mullen119 (Aug 30, 2009)

adrianmoisey said:


> Strange, I double checked and mine definitely has the rebound adjuster. The shock is a lot older (2007) I have it on my Giant Alias (http://www2.giant-bicycles.com/en-AU/bikes/mountain/1131/28948/?collections_id=3).
> 
> The rebound adjuster is a little knob on the bottom of the fork which you can turn towards a little picture of a rabbit or a picture of a tortoise.


That's really weird that my you guys have it and its not listed on srams website and my wife's didnt have it. The only thing I can think of is that rock shox has a deal where if the fork is OEM, it comes with external rebound. ( I picked my wifes up off the internet to replace an old suntour.) I am still suprised that it isnt listed on the sram website.


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## AndrwSwitch (Nov 8, 2007)

On any given line of Rock Shox fork, for example the Dart, all the features are modular. So a big enough manufacturer can ask for the Dart 2, but with a rebound adjuster. Or if you have a Dart 2 and wish you had a rebound adjuster, you can probably get your LBS to order the damper unit for you, and you can install it.

The same is more-or-less true of most other companies. My Manitou R7 can have two different kinds of dampers, and I could switch if I wanted to and could find the parts.

It's a little annoying when shopping for bikes because it can be difficult to figure out what, exactly is on the front end. And the badging and features don't always agree. I suspect I'm done buying complete bikes, as long as I keep riding a 26" hardtail, partly for that reason.


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## adrianmoisey (Jan 3, 2008)

So, I've got a Dart2 (with the rebound adjuster as we've discussed).
I'm quite light (81Kg) and the preload is set to the max (or is it to teh min?) so I don't get 2cm of sag.

What do I do? Change the spring?


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## AndrwSwitch (Nov 8, 2007)

The preload adjustment works by compressing the spring, effectively increasing the spring rate. So if you're light and it's not sagging much, you should lower the preload. If your preload is already at minimum and you don't feel like the fork is working well for you (harsh ride, or doesn't use its full travel on a typical ride) you need a lighter spring.

I found this chart with a Google search.

http://www.sram.com/_media/pdf/service/coil_spring_chart.pdf

Here's a spring kit for $18.

http://www.universalcycles.com/shopping/product_details.php?id=14119

They list springs for the 2007 Dart, which is what you have. I doubt that they've changed since then, and current parts are probably fine. I'd still talk to your LBS or e-mail SRAM tech support and make sure there aren't different, incompatible versions of the Dart spring kit out there.

At 81 kg, SRAM doesn't think you're light and you should have to have the preload set pretty high on the standard spring. Manufacturers will often spec a different spring on their small and large-sized bikes, though, so before you go off half-cocked, you should open up the fork and figure out what you've got. I'd also be a little surprised if you need a lighter spring. Have you ever rebuilt the fork? Does it ride differently than it did when it was new?


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## adrianmoisey (Jan 3, 2008)

Awesome, thanks for he advice. I'll find out what I have and check the preload adjuster


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## adrianmoisey (Jan 3, 2008)

I tried changing my preload adjuster, but it doesn't appear to do anything. Well... nothing I can notice.


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## AndrwSwitch (Nov 8, 2007)

The preload adjuster may not have much effect on sag and ride feel if you're on the wrong spring. It also may not preload the spring enough to do anything.

How much sag do you get? Do you sometimes bottom out? Do you bottom out a lot?


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## adrianmoisey (Jan 3, 2008)

I get about 10% sag.
I don't really bottom out a lot I think.

How do I know when I bottom out?


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## AndrwSwitch (Nov 8, 2007)

It depends on the fork. On the older ones, the fork travel would abruptly stop traveling and transmit a pretty powerful hit. I never notice it on mine, though - suspension's gotten better since the 90s.

If you put a zip tie on one of your fork stanchions, you can tell how much travel you've used on your biggest hit at the end of the ride. Most forks have a little bit of unused stanchion tube, so the zip tie should never get all the way to the top, but it should be pretty close.

If you're only getting 10% sag, you should figure out which way is which on your preload adjuster and back off a little bit. XC riders and racers on short-travel forks tend to go for 15% or 20% sag, but of course that's something to adjust to what you find you want for actually riding. Also, measure sag with dampers at full-open - a lot of forks will sag a little bit less with dampers engaged.


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## AndrewMiller (Aug 26, 2010)

AndrwSwitch said:


> The preload adjustment works by compressing the spring, effectively increasing the spring rate. So if you're light and it's not sagging much, you should lower the preload. If your preload is already at minimum and you don't feel like the fork is working well for you (harsh ride, or doesn't use its full travel on a typical ride) you need a lighter spring.
> 
> I found this chart with a Google search.
> 
> ...


Okay I want to get the soft black spring from the 2nd sight you have posted up but I have a few questions for anyone who may know the answer. I have a 2010 29er Dart 3 with 80mm of travel. At least I think it's a 2010 fork... it came on my 2010 Gary Fisher Mamba, but I gotta know if it will still work being a 29er fork with 80mm of travel. I only weight like 123 pounds so i'm goinna have to get something soon here cuz my fork is very stiff for me.


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