Suspension Setting/Testing Questions

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5/22/2018 7:07 AM

I am having a little bit of issues with one of my bikes. I have never really messed with suspension much and kind of just rode my bikes. My bike in question is a 03 rm 250. I went ahead and changed the front and rear springs for my weight based on race tech spring rate search. I set my sag to something close, and thought I set everything to pretty much stock. I have a few questions about how I should go about testing and what some issues I am facing.

With sag, and also goes for HSC on the shock it gives a pretty big range 95mm-105mm and 3/4-1 1/4 turns out. How do you choose a good starting point? Do you just start in the middle of every range they give you for stock settings?

Second issue, I rode a track after I did the work and I felt it worked really well. But this track has really well built jumps with good faces and landings that are really smooth with plenty of landing space, also the track usually gets bigger wider spaced braking bumps if it gets any. The bike seemed to do really well and I liked it.

So couple weeks later I took the bike out to a different track and they have dumped a ton of sand and they are working on it getting mixed in. I would say they are about half way from actually getting it mixed in. We also showed up at 1 in the afternoon so when we go there the track had little washboard like stutter bumps everywhere around the whole track. This track also has poorly made jumps. Flat ish faces and really flat short landings which make for very hard not smooth landings.

My two issues I had, first was with the stutter bumps, it felt like riding on a jack hammer around the whole track. Felt like my forks were not moving. But I don't actually know if I am way too stiff or if I'm riding around the track blow through the stroke and I'm almost bottomed out everywhere and that's why it hurts so much. Does anybody know how to tell this? Maybe have somebody watch? Second fork Issue is when landing hard off these poorly made jumps I tend to land a little rear wheel first and it feels so hard a couple times my hand was so close to coming off the bar. I have done these same jumps the same way on one of my other bikes even my 03 yz125 which has basically the same kyb forks and it does not feel like this. This maybe makes me think it is too stiff?

Second issue is with the shock when seat bouncing some jumps that I always seat bounce on other bikes and on this one before I did the work on it I was fine. Now I am getting kicked a bit. I feel like it is my rebound could be slowed down a tad but also was also wondering if my HSC is too much not allowing the bike to squat enough so I come off rear end high. I am sitting almost on the tank when I do this and usually I can sit on the back on this jump and be fine.

I guess the only way is to go out and start playing with settings but I wanted to know from you guys maybe some good things to try or how to start with or maybe my symptoms says something.

Thanks

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5/22/2018 7:48 AM

Strap a ziptie tightly around your lower fork tube and slide it up against the dust seal. Go ride the track and come back and check where the ziptie is. That will tell you how much travel you have used. Also, having someone watch you go through the section you were having trouble with also helps.

For the shock, HSC only effects your squat a little bit. LSC is really what effects your bike squatting on acceleration. HSC is mainly for square edge and choppy stuff, and hard landings, and possibly steep takeoffs. Unless you have no oil in the shock, rebound damping isn't going to cause your bike to want to frontflip. Chances are you are bottoming out the shock when seat bouncing and its deflecting. Try going stiffer on LSC.

In both cases. you should just spend a day at the track trying out different clicker settings and taking notes on what you like. Start in the middle, go ride a few laps. Then go drastically in one direction and go ride again. Take note of how it feels. Then go drastically in the other direction and see how it feels. Then you can take what you've learned and dial them in closer towards the direction you feel more comfortable.

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5/22/2018 7:54 AM
Edited Date/Time: 5/22/2018 7:54 AM

If you really wanna check your mind, have a buddy that’s good with settings. Or a suspension guy at the track. Tell him to adjust your stuff based on your feedback. And every once in a while tell him to pretend to change it. At random intervals. Then you can get a better understanding if sensing changes is in your mind as well... im not saying you’re an idiot. I’m the same way and sometimes I think an adjustment changed something drastic when it’s in my head. My suspension guy showed me this. FCR suspension outta Ohio.

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GP740
Since 1987

5/22/2018 7:58 AM

These are great podcasts by Keefer Tested, he’s a professional test rider and gives some great insights into your questions.

Suspension adjustments:
https://itunes.apple.com/us/podcast/rocky-mountain-atv-mc-keefer-tested/id1245516386?mt=2&i=1000389964898

How to Test:
https://itunes.apple.com/us/podcast/rocky-mountain-atv-mc-keefer-tested/id1245516386?mt=2&i=1000389079912

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5/22/2018 8:16 AM

Theycallmebryan, thanks I will do that. Good to know to not worry as much with the rebound. I thought about the zip tie thing. Probably should just ride the section in question and then check it because after I land off a big jump it could go all the way down but that is what I would want it to do on a big jump.

Georgie I cant afford a suspension guy haha, If I could I would be on a new yz 250 and would not have these problems like I do on my 03. I don't know anybody who knows suspension. I actually would like somebody to mess my settings up and see if I even notice. Usually I just ride the bike. And don't really notice stuff when changed. Had a shop do a revalve on an old bike once and could not tell. Got an over sized front rotor on my 450 and cant tell a difference. Really I'm only picky about my bars and levers, which makes me wonder how bad my bike is that it seems really bad compared to my other bikes.

Carlino I have listened to the keefer suspension clicker podcast and it is really good. But as he says in a lot of the situations it could be too hard or too soft. My problem is figuring out which one. Also the rear effects the front and front effects the rear. So maybe my rear is set up bad and its why my front feels bad but I could be chasing my tail by trying to only mess with the front.

Usually I don't worry about stuff and just ride but it feels a bit dangerous right now with almost knocking my hands off and some kicking when hitting jumps so I figured I should try to figure it out. I am just out there to have fun it is only a 03 250 if I wanna go fast ill get on my 450, it feels great.

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5/22/2018 9:22 AM

Hey Landis what are your rebound and compression settings on your fork and shock?

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2017 RMZ450
2005 YZ250-sold :,(
1998 YZ250
2005 KX250F

80% of the time it works every time
IG @2HRacing
Thanks to : Factory Effex, N2Dirt, Acerbis, DT1, Fasthouse, Matix, FMF, ASV, 100% & Mika Metals

5/22/2018 9:27 AM

mattyhamz2 wrote:

Hey Landis what are your rebound and compression settings on your fork and shock?

I'm not sure I thought I set everything to stock but Ive gotta check. I'm going to set everything to the middle of the range for stock settings and go from there I think.

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5/22/2018 9:33 AM

mattyhamz2 wrote:

Hey Landis what are your rebound and compression settings on your fork and shock?

lcgordon711 wrote:

I'm not sure I thought I set everything to stock but Ive gotta check. I'm going to set everything to the middle of the range ...more

Set rebound at 14 and compression at 12. It's kind of a general setup that a few suspension tuners that I know use. Makes it easy to go from there.

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2017 RMZ450
2005 YZ250-sold :,(
1998 YZ250
2005 KX250F

80% of the time it works every time
IG @2HRacing
Thanks to : Factory Effex, N2Dirt, Acerbis, DT1, Fasthouse, Matix, FMF, ASV, 100% & Mika Metals

5/22/2018 9:36 AM

Is that for fork or shock or both?

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5/22/2018 9:37 AM

How much do you weigh? Were the forks stock from a spring and valving standpoint?

When you set the sag did you check the static sag? This helps determine if you truly have the correct spring rate.

Your goal is to 1) have the correct spring rate on the shock so that you can set the sag (and have the static sag in check). 2) adjust the forks so that the front and rear balance. If the bike doesn't feel biased (front end high or front end low) when riding it around normally then you're probably pretty close.



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5/22/2018 9:47 AM

I weigh about 170lbs. I used the race tech tool to imput my number and I think stock is .44 and 4.9 and I went to a .46 and 5.2. I also used recommended oil at 110mm. I don't think they had a static sag number in the manual. Maybe they do I cant remember. I'm pretty sure my sag is right around 100mm. I want to re check it again and write down all my numbers on everything. Honestly I just put it close to sock I think on everything thinking I would not really know the difference.

The valving is stock as far as I know in that I have never messed with it. It had stock springs in it before so it was all probably stock.

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5/22/2018 10:00 AM

lcgordon711 wrote:

Is that for fork or shock or both?

Both

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2017 RMZ450
2005 YZ250-sold :,(
1998 YZ250
2005 KX250F

80% of the time it works every time
IG @2HRacing
Thanks to : Factory Effex, N2Dirt, Acerbis, DT1, Fasthouse, Matix, FMF, ASV, 100% & Mika Metals

5/22/2018 10:09 AM

I wanna say they are at 10 and 12.

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5/22/2018 11:55 AM

I dont think your spring rates are too out of spec. What happens is when like a 250lb person resprings a stock bike with no valving change you'll see issues with how the suspension performs.

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5/22/2018 11:56 AM

TJMX947 wrote:

I dont think your spring rates are too out of spec. What happens is when like a 250lb person resprings a stock bike with no ...more

I cant attest to that.. riding in the bottom of the stroke sucks dick

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5/22/2018 12:13 PM

Yeah I’m going on a two week vacation so hopefully after that I can get some testing results back up here and maybe some video.

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5/22/2018 12:26 PM

If you install stiffer springs without changing the valving, you'll likely need to soften up the compression damping and slow down the rebound damping to compensate/ get the same feel.

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5/22/2018 12:32 PM

The same feel as before with stock springs? I don’t want that either bottomed our everywhere was really soft. I just need to try some stuff

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5/22/2018 1:44 PM

how many hours of the rear shock oil?

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5/22/2018 1:45 PM

Changed oil when did the spring so maybe 3hrs now

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5/22/2018 6:53 PM

Checked the current settings tonight
Shock
Reb 9
Hsc 1 turn out
Comp 8

Fork
Reb 10
Comp 10

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5/23/2018 1:06 AM
Edited Date/Time: 5/23/2018 1:07 AM

Check your static sag with the 5.2 spring, you might find its too stiff.

I'm 180lbs intermediate and really like the stock .44 fork springs with a 5.0 spring in my 2008 RM250.

Check the static sag figure and report back, you should be aiming for around 30/35mm with 100-105mm rider sag.
I've found Race Tech to air on the stiffer side with their spring rate recommendations.

Your current settings seem a little stiff and could well be the cause of your issues.
If it was me I'd try the following:

Shock
Reb 8
Hsc 1 3/4 turn out
Comp 12/14

Fork
Reb 10
Comp 14/16

Use a zip tie to monitor fork travel. You may find you can come out even softer on the compression to 18 or 20 out with the 0.46 springs. Alternatively, reducing the oil qty in the forks helps to soften them, particularly in the 2nd half of the stroke.

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@russ_69

5/23/2018 1:15 AM

I have found the racetech calculator to be slightly stiff on springs, especially fork springs. I'd try switching back to the stock fork springs or use one stock spring and one racetech spring to get an in between rate.
Also check the stock springs and racetech springs are the same length. If the racetech springs are longer you may have too much pre load on them

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5/23/2018 6:21 AM

Thanks guys for the help. Remember I do have the kyb bumper forks so they are different than your 08 Russ. Everybody said if you were over 150 lbs you had to go stuffer in the forks. .46 is only one size up from the stock .44. Everybody did say get the showa forks but I refused to believe that I needed to spend 300 bucks or forks, 150 on revalve and 120 on springs to go out and have some fun. Not always but a lot of times I have found ppl on the forums to sit and pick fly shit out of chili, so I believe that I can get something that is fun and rideable with the stock forks.

I’ll go out and do some testing. I will also check my fork height.

I don’t have any friends who know anything at all about watching somebodies suspension. I don’t even trust him to do an air filter by himself so I will get some video.

Just wondering stock says like comp 10 and reb 12 if I went to comp 14 do I need to make rebound 15-16?

Thanks for all the help. I will probably be back on in 2 weeks when I get home and can go ride again

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5/23/2018 7:01 AM

lcgordon711 wrote:

Thanks guys for the help. Remember I do have the kyb bumper forks so they are different than your 08 Russ. Everybody said if ...more

Of course, I forgot the 03 uses KYB's.

However, I'd still recommend putting a zip tie on a fork leg and checking your travel usage. The different linkage on the 03 may warrant the stiffer rear spring. But in terms of forks, you generally don't see much variation in spring rate between fork brands.

I have never ridden the 03 KYB fork so cannot comment on its performance, but I'm sure its a perfectly decent fork. I'd agree it seems extreme to switch to newer Showas.

The compression and rebound adjustments are totally independent and don't need to be adjusted together. So yes, you can do whatever adjustments you want to the compression, and not need to touch the rebound (and vice versa)

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@russ_69

5/23/2018 8:23 AM

Yeah everybody hates on the forks but they are probably basically the same as the forks on the early 2000s yz bikes and people like those. Just in 03 the Showa had better technology at that point.

I did hear Keefer say when you go stiffer compression by day two clicks you should probably open up the rebound one click. I’m guessing open means out so it has less damping so it springs back faster

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7/2/2018 8:00 AM

Took a while but got back on the RM this weekend and did some "testing". At first felt really weird in the rear. Kinda high and springy maybe. Forks felt hard like they bottomed out a lot.
Stiffened the forks up and they seem better most of the time. They seem better on the first 1/4 ish of the stroke but kinda hard through the mid and soft on the bottom maybe. If you land a jump wrong it sucks. If you hit breaking bumps pretty hard it can be kinda harsh.

The forks would be at
8 comp
10 reb
110mm 5w oil ( stock says 150mm-110mm) race tech says 110mm. Some people said to lower oil height to get rid of mid stroke harshness but how can you get more bottoming resistance? Do I just need to revalve?

The shock was really funky.
Went out with
8 comp
9 reb
1 3/4 hsp
the rear kinda felt high and springy like it wont stay squatted.
then I tried
10 comp
7 reb
1 1/2 hsc
and was maybe a little better but then figured I needed to mess with sag. Some guys next to me helped me out and actually had a sag scale. I had set it with under an hr of ride time with a tape measure at 100mm. It was at 114mm WTF! So I changed it to 104 and rode and it was a lot better but not perfect but was ride able now. Not sure how I was that far off. I went home and ordered a sag scale that day.
I would maybe like the rear end to squat a touch more and stay down on the face of a jump. Hitting one jump with a smooth not steep face sitting down when I first get on the face it kinda rebounds my butt off the seat and I cant stay down on the seat. My 450 just stays smooth and squatted the entire face.

Any ideas on what I should try?

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7/5/2018 9:03 AM

Anybody have experience with the race tech gold valves for older style forks. Did some riding yesterday and the forks feel really good initially. Stiffening up the low speed compression really helps them hold up. But when you hit harder the mid stroke seems really harsh. To my knowledge I could lower the oil level to take some of that harshness out but that is also what gives me bottoming resistance. Right now I don't have much bottoming resistance. Im thinking I could do a revalve to help with that and then lower the oil level a bit to make the mid a little less harsh.

Wondering if the race tech gold valves would be a good option for me?

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