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Need helping balancing suspension

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I am having trouble setting up my suspension. The problem was the bike wouldn't stay in a rut. I am "5"'10" AND I weigh 135. My fork springs are .42 and the shock spring is 4.5. And I am a fast beginner. So here are the settings I came up so my bike will stay in a rut:

1. Sag at 93mm

2. fork compression at 14 clicks out

3. fork rebound 9 clicks out

4. High speed compression on shock 1.5 turns out

5. Shock rebound is at the stock setting 10 clicks out

6.Shock low speed suspension is the stock setting at I think 7 clicks out .

7. fork oil level at I think 130-140mm and the bike is within 1/4 to 1/2 of a inch to bottoming.

8. Forks 8mm up in tripple clamp.

But with that setup my bike turns perfect in a rut and I didn't get any headshake at all. But now the problem is if the turn is flat the back end justs slides around and like squares off the turn even though I don't want to. My rear tire is a Michelin MS3. So how can I can I make my rear hook up while having enough weight on the front?

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You didn't mention tire psi. Try a little bit lower. Not to low for the terrain . In the turn load the outside footpeg (ass 1/2" off the seat)while getting far forward and gasing it. Remember the gas control is all in your clutch finger. Now that you feel the bite lean back (not slide back) and lift the bars . :banghead:

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I started the day off at either 10.5 or 11.5 PSI but I forgot to check it during the day. And the terrain was intermediate.

Will to much rear compression not cause the rear tire to hook up well?

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riding ruts is also a timing thing, when your on the front brake coming into the turn you dont want to realise the front brake until your are ready to accelerate,

its best to gentley realise the front brake as your body weight moves forward and down on the seat/tank so as keep the front end springing back up, this will toss you out of the rut.

so as youve fully realised the front brake be ready to accelerate.

if by chance the front still tries to pop out try pulling a small amout of front brake while your acellerating, this will collapse your fork a little and hold the front end in the rut, its near impossible to pop the front out using this method.

but most important is brake timing because once you have your forks loaded coming into a corner you dont want to reliese that load to early and have the front rebound and throw the balance of the bike out.

usually staying in the standing position as long as possible will have you doing this automatically.

and if you find youve braked to heavy to early, still let the bike loose more speed than needs be, as if you try and reliese the brake and activate it again youve lost the balance of the bike and may most likely wash the front end out.

maybe you already know this but if you dont it a huge help

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What you have is a prolonged stability problem, which is seldom related to damping.

In other words, damping deals with dynamic matters, events that happen within fractions of a second, whereas these issues are occurring for your entire time within a corner.

With that, I would look at tires and everything springs (springs, oil levels and nitrogen PSI). Assuming of course that the mechanics of your suspension is in order (no binding and such).

Now, a .42 and 4.5 combo seems a bit soft particularly in the front, (considering your "beginner" status). This is why you can easily get into a supported corner but can't keep the back end in place when it's flat. However, spring rates are very much related to rider level, and it's possible that your speeds and comfort level (which leads to demand) are very different in ruts than they are on the flat stuff.

What I mean is - it's common for beginners to push the bike more in the flat stuff and be slower and more hesitant in the ruts, making spring selection even more tricky.

As for tires, for most parts of California there's only one choice - the F and G versions of the 739. (yea, I know, we hate 'em, we love 'em). I have worked with Bridgestones and Michelins which can be really good under certain conditions, (and certain rider levels) and of course the 756 and 756RR are also a good choice (particularly for concrete starts) but nothing brings a 4-stroker to life like the F and Gs...at the right PSI. Let's say nothing over 12.

Given this, I would add as much pre-load to the fork spring as possible, which is not much, but it will help. Then I would maximize the fork oil, (highest amount of oil, lowest setting). This will allow the bike to dive and plant, but not so much that the rear will want to lift.

Then as you improve, you're going to find the need to switch to a stiffer, and soon a much stiffer fork spring.

BTW - what parts of California are you in? If you're local, I may be able to meet up at one of the tracks and help out.

DaveJ

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I have the stock .44 and 4.8 or 4.9 springs. Should I put the .44 springs back in and test it? Or should I put some preload in and put the oil level to the 80mm or whatever is the highest setting?

DaveJ, I live in Hollister.

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Put the bike up on a rear stand and measure the compressed (pre-loaded) height of the rear spring. Or pull the shock and measure it if need be.

Be as accurate as possible.

Let me know what this value is and I can tell you what direction to take.

And I'm in Los Gatos. Testing at Hollister is a bit tricky since the only two tracks are the MX and TT, which ain't much when it comes to setting a bike up. Too bad the GP track isn't open more often heh? Metcalf or the CMA track at the fairgrounds is best. Ever go?

DaveJ

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Okay I just set my sag at 98mm and my forks 12mm in the clamp and I will test it tomorrow. And I will tell you guys how everything is.

Yeah Hollister hills isn't the best place to ride or test because because the tracks are sooooo hardpacked. Did you race/practice at the GP track last weekend? That place is hecka fun!! Metcalf it kinda fun when it is watered. How is the San Jose fairgrounds track? Because I am planning on going there next Tuesday. The thing that sucks is that I am only 14 years old and my dad doesn't always have the time to drive me really anywhere farther than Metcalf most of the time and that terrain isn't the terrain I usually race on so I it would be pointless to test there. But when my brother gets his drivers license next summer I will be going riding to places that are farther away that are not hardpacked and that forms ruts like at tracks I usually race on.(ex.club moto,GP track)

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I was down south over the last few weeks so I was not able to attend the GP event. Bummer since it's not open very much.

And you're right about the Metcalf track - it's useless unless it's watered. However, it has plenty of hoses and I always thought about using some using sprinklers when I'm there. Could make things fun.

And the fair ground track is very different than all the rest. Some people call it a Supercross track which is far from the truth, but it does require a bit more attention than say Club Moto or the GP track. It's all corners and jumps.

Now, the issues that you need to address with your set-up are very elementary, but still very important. In other words, it has little to do with terrain and all about validating spring selection. Additionally, never discount a track just because it's not exactly what you race (dare I use that word) on.

With that little snap of a whip, I'm usually at Metcalf about twice a week, and sometimes at the fairground once a week. So just let me know when you can get a ride and we'll go from there.

If not, perhaps I'll just run into you (no pun intended) at some other point in time..or track.

DaveJ

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Put the bike up on a rear stand and measure the compressed (pre-loaded) height of the rear spring. Or pull the shock and measure it if need be.

I feel like an idiot, but what do you mean?

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And the fair ground track is very different than all the rest. Some people call it a Supercross track which is far from the truth, but it does require a bit more attention than say Club Moto or the GP track. It's all corners and jumps.

How is the fairgrounds track? Can you tell me what hard things there are on the track? Is it fun? Is it a very tight track? Does it have whoops or huge jumps. Is it better than the GP track or Club Moto? Dang, I ask a lot of questions. But hey I am 14 what else am I supposed to do.

Thanks

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I feel like an idiot, but what do you mean?

Only idiots don't ask.

What I mean is...put the bike on the stand so the wheels are not touching the ground.

Then, measure the length of the rear spring from end (top edge) to end (bottom edge). In other words, you need to measure the compressed length of the spring, when the shock is fully extended. It's tricky, so you may need something other than just a tape measure.

This value, when compared to the amount of sag produced, is a valuable measurement in spring and pre-load configurations and bike-balance evaluations.

In other words, there is a relationship between set pre-load spring length and sag. These numbers can then be used to determine and evaluate spring rates and proper sag settings.

If you let me know what your pre-load spring length is at a particular sag setting, I can then tell you, with something more than an educated guess, if you're running the right spring.

Make sense?

DaveJ

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The track is great, but it's $20 to $25 to get in, each time. However, if you wait until later, the gate man is often on the track and not able to collect your funds. :banghead:

However, the track is not for the casual trail rider that wants to go ride a "track". For example, at the GP track I usually ride mid-pack with the pros and intermediates. At Club Moto, I seldom get passed. At the fairgrounds track, I barely have the ability to keep myself out of trouble and get whipped by many.

But, to no surprise, there is always someone out there on an old 1980's RM that is managing quite well to stay out of trouble at a very slow speed.

The whoops are weak, (by comparison) more like an un-even rhythm section, but still enough to toss you over the bars if you don't hit them at speed. They often don't look that bad, but when you're on them it takes some skill. BTW - my whoops speeds are really low, so this is where I often get by butt kicked. They also change the track around every now and then so I'm not exactly sure what the current configuration is.

And they use to have some nice doubles, with really nice gaps, which I really REALLY liked, but they took 'em out.

And...it's mostly a second gear track. Whereas GP and Club I often visit 4th. This most likely makes it safer. It's the one track that I have ridden where you can really develop skills to manage the bike under tight conditions....jumps, rhythms...etc.

You just need to go and check it out. You'll be fine.

Does that help?

DaveJ

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I am having trouble setting up my suspension. The problem was the bike wouldn't stay in a rut. I am "5"'10" AND I weigh 135. My fork springs are .42 and the shock spring is 4.5. And I am a fast beginner. So here are the settings I came up so my bike will stay in a rut:

1. Sag at 93mm

2. fork compression at 14 clicks out

3. fork rebound 9 clicks out

4. High speed compression on shock 1.5 turns out

5. Shock rebound is at the stock setting 10 clicks out

6.Shock low speed suspension is the stock setting at I think 7 clicks out .

7. fork oil level at I think 130-140mm and the bike is within 1/4 to 1/2 of a inch to bottoming.

8. Forks 8mm up in tripple clamp.

But with that setup my bike turns perfect in a rut and I didn't get any headshake at all. But now the problem is if the turn is flat the back end justs slides around and like squares off the turn even though I don't want to. My rear tire is a Michelin MS3. So how can I can I make my rear hook up while having enough weight on the front?

To me, it sounds like too much weight bias forward. Cahnge your sag as suggested and test. If better but not great, slow the rear rebound down 1-2 clicks to keep the back end down. If you like this leave it alone. If not great, speed the HS rear comp up about 1/8 turn in an effort to get the rear to squat a little more.

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Well after riding yesterday I felt like the front end wanted to tuck and of course the the rear didn't want to hook up so I went 3 clicks out on the fork rebound and went 1 click in on the shock rebound. Then I dropped the forks to 5mm above the triple clamp. And finally set the sag at 100mm. And now it turns great but it could be better alittle with a little more setup.

But I think why my bike wouldn't stay in ruts well that one day was because of rider error therefore me setting up too much weight on the front then my rear wouldn't hook well. Rider error was not having elbows up enough, not using the front bikes in to the rut enough, and not sitting far up on the tank enough.

Thanks for your guys help

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Well after riding for 2 days I found out my bike did good in ruts. But everywhere else my bike felt I guess I could say "mushy". Also it just felt like the suspension went farther down in to the stroke on everything it needed to and it bottomed kinda easy. Like even over a small 15 foot it felt like I was almost bottoming. And it just didn't have a good handling feel to it. What part of the travel do springs affect? I always thought they affect the whole stroke but I just want to make sure. I am thinking of going back to stock springs and testing. Or is there anything else I could do. I just want to get rid of the "mushy" feel.

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The mushy feel is from soft springs.

I think you'll be happy when you convert.

And the answer to your question is yes, they effect the whole stroke.

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one easy thing to try is more air pressure,when you run to low of pressure in tires the middlle of the tire doesnt touch the ground just the verry outsides of the tire.may not work,but very easy to try,

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Put the bike up on a rear stand and measure the compressed (pre-loaded) height of the rear spring. Or pull the shock and measure it if need be.

Be as accurate as possible.

Let me know what this value is and I can tell you what direction to take.

DaveJ

Dude, sorry for not measuring the compressed height of the rear spring. It is like every time I go to my garage to work on my bike(which is like everyday since it is so fun to work on my bike) I do everything except for measure the height of the spring. I hate forgetting. But I promise I will get during this weekend. Because I might go riding tomorrow, but I don't know where yet.

Ok so I put in my stock springs which are .44 and 4.8 and now it handles awesome. In braking bumps it feels much better and it doesn't feel mushy and it jumps great now again. But now I am back to my original problem and that is it won't turn like crap probably because the front end isn't diving and staying down. The front end just won't stay in a rut and it feels like the front end just like slides around when I am cornering instead on just stay put throughout the corner.

So I am going to through the same process I went through with the softer springs and change the sag to 98mm and if that doesn't help then I will mess with rebound and things until I can get it to turn right . Then I will give you guys an update.

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