Help, DIY pro style shock revalve yz450f -10

Allthough I am not pro fast I have found that in general what works for the pros works for me. Help me set up my new 2010 yz450f suspension. I have complained through my youth about poor suspension. This time around I am determined to get good boingers. After some time off I returned to riding last fall on a 2009 yz450f. I am 6'1" 180 lbs. My best setting on the 2009 was:

15 cc oil added to fork

comp zero out (all closed)

stock rebound fork and shock

shock hsc 3/4 out (stock 1.5 out)

shock lsc 2 out

stock spings, race sag 100 mm (not played with sag yet)

Basically the stiffer I got the compression the better it suited me. So for my 2010 I have done a plan for my shock shimstack. I want it dead feeling so I want less free flow, stiffer comp and faster rebound.

shock comp

……………………. stk ……………………. mod

……………………. 44.2 - 13 ………………. 44.2 - 13

……………………. 34.15 ……………………. 34.15

……………………. 44.2 ..……………………. 44.2

……………………. 42.25 ……………………. 42.25

……………………. .........……………………. 40.2 - 2

……………………. .........……………………. 40.3

……………………. 40.25 ……………………. 40.25

……………………. 38.25 ……………………. 38.25

……………………. 36.25 ……………………. 36.25

……………………. 34.25 ……………………. 34.25

……………………. 32.25 ……………………. 32.25

……………………. 30.25 ……………………. 30.25

……………………. 29.25 ……………………. 29.25

……………………. 28.25 ……………………. 28.25

……………………. 27.25 ……………………. 27.25

……………………. 26.25 ……………………. 26.25

……………………. 25.25 ……………………. 25.25

……………………. 24.25 ……………………. 24.25

……………………. 23.25 ……………………. 23.25

……………………. 22.25 ……………………. 22.25

……………………. 21.2 b ……………….

shock reb

……………………. stk ……………………. mod

……………………. 40.2 - 4 ……………. 40.2 - 2

……………………. 29.12 …………………. 29.12

……………………. 40.3 …………………….

……………………. 38.3 ……………………. 38.3

……………………. 36.3 ……………………. 36.3

……………………. 34.3 ……………………. 34.3

……………………. 32.3 …………………….

……………………. 30.3 ……………………. 30.3

……………………. 28.3 ……………………. 28.3

……………………. 25.2 b ………………. 25.2 b

The rebound clicker free flow short-cuts the ls compression so I plan to run soft rebound shimstack and close the reb clicker several clicks. This should give me more ls comp, slightly slower ls reb and faster hs reb.

I believe I am happy with the stock springs. The 2009 suspension was to soft for me but the 2010 has stiffer shock spring and sinse I plan to go with stiff damping I think the stock 2010 springs will be good. Stock fork springs and oil height and maybe 115 mm sag will allow bike to settle in turns. The stiff damping and fast rebound will keep the suspension up in their stroke.

I am willing to work for it and pay for it. I am convinced I will have to do both. This is where I start the journey :smirk:. I have a plan for the forks too after we have discussed this.

your input is valuable.

personally i would do what you suggest on the hs comp , but you need to beef up the low a little more IMO, maybe add 2 face shims.

On the rebound, i would not go so light on shock rebound, you run the clicker that far in and it will heat up the shock really badly.If anything i would stiffen the rebound more and comp stack even more to compensate.And run the rebound clicker more out.

I would go no more than say 107mm sag.

Thanks for your input, good call on the heat. I don't see it happen though. Adding comp damping will generate more heat, there is no escaping that. But I plan to keep or lessen the rebound damping so it must therefore generate less heat.

The reason I did not add face shims is (apart from not having any) is that the extra 40 mm shims will give both more hs and also a little ls. My plan is that the reduced free flow will (hopefully) add quite a lot of ls and the stock number of face shims will allow for a smooth transition from free flow damping to shim damping.

The tricky part for me is to see whether I get the rebound free flow low enough to stiffen up the lowest speed comp and at the same time get somewhat normal rebound damping. I can then increase the mid to hs comp by going bigger on the clamp shim. My aim is to have equal or just a smidge slower ls rebound and slightly faster mid to hs rebound.

Keep te suggestions coming.

yes you are creating whats called a low bleed setup, i can see your thinking but i think it will be enough, your cutting the free bleed will not increase damping enough, because as soon as the shock is moving with any speed the free bleed is not going to make much difference, then you are on the low speed part, and thats not going to be stiff enough to get your adjusters back to something like middle, it will work as you describe but it wont be enough.

When you do remove free bleed you will increase shock temps significantly, at the moment you dont see it , as your clicker is out a decent amount, you will see it when you try to cut off the free bleed to give more damping, i had big problems with shock temps with a soft rebound stack.I also had big problems with a huge kick in breaking bumps once i get the rebound less than 6, it was borderline dangerous.

On forks i did a test with 455 (steve) to go from 2-3 clicks out to 12, we had to increase the stack strength massively, 2-3 face shims(eg 12 to 14) only gave a few clicks.

the extra shims in the hs will give more low speed as you say, but no where near enough, if you have no shims just go to a much bigger clamp, like the 24, it will achieve all you are after.

Going to large sag numbers like 115mm will ruin the handling IMO.

Nice to get good help. I am listening. So you suggest I use that comp stack but with a 24 clamp. I like it, sounds like something I want to do but I was afraid a 24 clamp would be too much. But if you think it will work I will listen to advice.

Interesting info about how much you have to stiffen the stack to get just a few clicks.

About the sag, it was just an idea. I will start with normal numbers and try different settings to see what works. The thinking was that the dynamic sag would be less than 115 mm if I went stiffer on comp, maybe I thought wrong.

I think you give quality advice mog. I am looking forward to also hear what other tuners will bring too the table.

yes always good to get some extra info, suspension ideas are not set in stone,many ways to achieve the same thing.

I would run race sag set at 105m on this bike because it has a little stingbug stand. So i wouldn't stiffen it much but I would stiffen the reb. That's why I suggested you to run stiffer fork spings also on the other thread.

I'll try with stock fork springs first and get stiffer after testing if needed.

I conclude that you do not agree with my suggested mods for the shock reb. I hear you and will maybe reconsider. I would like some more opinions on that, and off course on everything else. Other tuners please chime in.

mog and jusa, million thanks for your help. Please keep bugging me if there is any more details or suggestion you want to contribute. I love to learn much more than I love being right.

with suspension its not right or wrong really, its about rider choice, you may love the feel of less rebound damping, most dont but some pros do, so to some degree we are only guiding you based on what you have told us so far, we maybe going in the wrong direction for your personal rider preferances.

Stiffer com valving will cause some kicking in some cases and when you decrease your reb rear will kick much harder. Not always but I guess this is the bike that will do it. I have talked also with some pro riders and they said that they add some reb dampening (yamaha riders).

Pro setting baseline.

Rider 80 KG Pro

comp side

stock comp with a 23.3 clampshim

+ 2 40.2 on the reb side

stock spring.

reb setting ~ 16-18 out

:smirk:

Sweet, 23 clamp it is. Everyone is against me on the fast rebound :smirk: Ok maybe I have to listen to good advice when I get it. Thanks

Sweet, 23 clamp it is. Everyone is against me on the fast rebound :smirk: Ok maybe I have to listen to good advice when I get it. Thanks

fast rebound setting for faster Riders ??

yes, of course..

but not with the valving.

a stiffer reb valving with more bleed (open clickers) works much better.

fast on the bracking bumps and safe on larger hits and after bottoming.

You will be amazed.

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