So, having finally gotten a big bore kit on the bike, its time to take the next step. This is going to be a really long thread with lots of questions, but I hope someone can offer some insight. It seems that everyone sort of agrees that the stock springs on the KLX250 are rubbish. I have read all the old threads on the topic and it seems like most go with the motopro or racetech springs.

Well I have been researching a little bit about what is available here in Europe and I found out about a Dutch company Hyperpro, who make progressive springs. They deliver a complete set of progressive springs for the KLX front and rear for 125€/170$ which I think is fairly cheap. When reading on the internet, Hyperpro seems to be a good company that is known for delivering quality, so that part is pretty good. On the website it says the springs are for:

"KLX 250 - Year: 01> - LX250E"
"D-TRACKER - Year: 01> - LX250E"

The 2009 KLX250 is a LX250E am I correct?

(Check out page 7 of this link: http://www.hyperpro.com/hyperpro/sit...%20Springs.pdf)

• One thing that confuses me is that I see the springs for the KLX250s and the D-tracker have the same parts number on their website. I thought these springs were not the same on both bikes since the D-tracker has different suspension set up?
  
• What are the pros and cons of a set of progressive springs over regular springs like what motorpro and racetech offers?
  
• When ordering progressive springs, I would still need to figure out which weight I want them for, right?
  
• Would just changing the springs give me much improved suspension or is it a "Half measure?" I see people are also doing revalves and even complete fork swaps. Im trying to get bang for buck here.
  
• Honestly, the bike feels okay on road except for the front end dive on braking, but on gravel it feels very unstable, especially when trying to turn. Can I expect a noticable improvement in this area?
  
• Finally, I am unsure about setting up suspension. I can install the springs myself and set the race sag, but what else would I need to do in order to get suspension set up for me?

 

What do you use the bike for and how much do you weigh? What is your level of experience and how hard do you hammer it off road? I know these are very personal questions, but relevant to anyone wanting to give you the correct advice.

 

I'll plead ignorance here, but aren't those D-Trackers the same travel as the '07 and earlier KLX's?...that is around 11"? On progressive wound springs in general, I think they are a good match to bikes that have forks with ported orifice dampers and no shim stacks like the KLX. I used them on KLR600/650's, and they worked great, but shim stack forks usually do better with straight wound springs...generally. In fact, I think progressive wound springs were mainly designed for ported orifice forks where end of travel damping wasn't the greatest. None of this is to say they won't work in a shim stack fork, but I don't think it's usually the best match. In fact, the KLX usually has a compression spike in the mid-to-end-of-travel, right where most progressive wound springs are starting to kick in. Just my 2 cents, without more knowledge on these particular springs.

 

Graham. I use the bike mostly in the city where the stock suspension is decent except for the annoying dive in the front forks when braking.The bike spends 90% of its time on asfalt.

However, every once in awhile I take it out into the terrain. No mud or anything like that, mostly gravel roads, hard dirt fields and hard sandy beaches. On the gravel roads in particular, the bike feels unstable when turning. I am also planning to do a very long trip next summer that will be mostly on bad asfalt roads and gravel and I want to make sure the bike will be able to handle that trip well.

As for my experience. I dont have much. This is my first bike and I am still learning. I am not really hammering it because I dont have enough confidence, but id like to ride faster.

I weight probably 78kg with gear. For my trip i will probably carry 30kg of luggage or so.

TNC. I have no clue on the suspension travel differences betwene the years and the models. I heard there is a difference between the 07 and earlier KLX and the newer 2009 and after models. I also figured there would be a difference between the dirt version and the sumo version of the bikes. Im just confused because their website displays the same part number for a 2001+ D-tracker and KLX250. I dont think every version of the bike made since 2001 uses the same springs?!

I think I will e-mail hyperpro and ask them. I just wanted to get some things cleared up before I started asking them questions.

 

The KLX has a linkage rear end with rising rate, therefore there should be no need for a progressive spring.
I went for 2 clicks more compression damping F and R. Seems to work quite well for a 145lb rider.

 

I thought we were talking only about fork springs, but I see the OP mentioned front and rear...though the main complaint is fork dive. The front springs aren't "rubbish", but they are generally too weak for most rider weights...over 160 pounds. The rear spring is a lot more usable for most riders, but at 190 pounds, I went to a 6.0 rate for the rear.

DT's comment about the rear spring not needing to be progressive is correct due to linkage and rate design. I still contend that a progressive spring is not the correct match to the fork on the KLX in particular due to its overly aggressive compression spike in the shim stack. I'd install a more proper straight wound set of fork springs to match rider weight and riding style, and then revalve later if necessary. A better matched rider-to-fork-spring weight will be a noticeable improvement.

 

Well. I spoke with Hyperpro and their springs dont fit the 2009 model anyway, so progressives is not an option it seems. So many suspension manufacturers here in Europe and nobody makes springs for a 2009 KLX?!

I think I will have to go with Motopro even if it means paying ridiculous customs fees once more. I used the calculator on their website and at 165lbs(my weight) it recommends 0.40 front and 5.6 rear. I really dont know much about suspension, but it doesnt seem like a very big change. if I calculate 230lbs (me + my luggage) it recommends 0.44 front and 6.2 rear.

Reading old threads, it seems that people here think that you should go with harder springs than the calculator recommends. I dont ride hard offroad, mostly asphalt with some gravel and hardpack dirt and sand.

So whats the verdict here, should I go with what the calculator suggests? Maybe I should go with springs front/rear for something thats in between my weight and weight + luggage.

On the other hand, it might be stupid to factor in the weight of luggage when I only ride with it about 5-10% of the time.

 

Check out this site regarding KLX suspension, it has a lot of good info. KLX TECH TIPS*-- SUSPENSION ADJUSTMENTS

Having issues with cornering on gravel roads? Have you adjusted the rear sag yet? Having proper Rider Sag will help with this. Check out the Sag Adjustments section.

There is a spacer mod on this site that will help fix some of the fork dive. I have not performed that mod but it seems cheap and easy. Other than that, only way I have seen to eliminate the fork dive is to get new springs.

 

Interesting site JaMan. Does the info relate to pre 2009 KLXs though? These have different geometry and travel to 2009 on.
I don't find the rear too hard on my 2012 model (like it says on the site), it's easier to bottom the rear than the front. That's why I increased the CD 2 clicks.

To the OP:
I'm not convinced progressive fork springs will help reduce dive, they will make it worse if the 1st half of the travel is softer! What you need is more low speed CD - although I have no idea how to achieve this on the KLX without adjusting the overall CD.

 

With most of your riding being on asphalt or hard packed roads, you don't need to set the suspension up to make use of its full travel. I'd go on the firm side when selecting the springs. I weigh in at 160 lbs without gear and use .42 fork springs in my KLX300, which is dirt only. I would guess that you street version bike weighs in at more than mine so the front end will be carrying more weight and need even heavier springs.
The recommended spring rates on the KLX TECH TIPS are for the dirt model KLX 250 and 300.

Ride on
Brewster