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Location
Philadelphia, PA
US
2017 Husky FC 350
Motocross
Vet - C class (pretty decent in corners, chicken shit on jumps for now)
170 lbs
My understanding of suspension is this, and should be done in this order:
Spring Rate - objective number based on rider weight
Valving - subjective based on riding type & skill. Also used to fix flaws in OEM hardware.
Clickers - fine tuning to suit speed/skill of rider
Bike in stock form felt really tall in rear. Yet OEM spring is 42 and should've been perfect for my weight. In OEM form, bike came with:
6mm preload
35mm static sag
105mm rider sag
I added the Pro Circuit linkage. That dropped the rear considerably and threw off the Spring Rate. Rider sag jumped to 140mm.
Oddly enough, I was more comfortable on the bike in the turns. And thus faster. It felt lower and I could “feel” more.
I was costantly taking shit for my setup tho from friends who are way faster than me and know more about this sorta stuff.
So I got the right spring (45n) and set it to 6mm of preload.
At 6mm of preload, this was where we were:
43mm static sag
116mm rider sag
Maybe I could’ve gone a spring stiffer? Im on a weight loss mission so I’ll make it up on that end.
I got the static & rider sag down to where it’s recommended (35/108). Went riding. Back to where I started when the bike was new. Felt too tall in the corners.
Im considering raising the sag back up. Minimal preload (6mm).
This will raise the rider sag to 116 again. Still way lower than what I liked before. But also way out of whack from what is recommended. What is the downside to this? And am I chasing the wrong gremlin?
My next attempt is to increase the rebound dampening considerably so that the bike starts to pack a little once I set it in a rut. This will give me the feel Im looking for (low rear) or am I wrong?
Any and all advice welcome.
Motocross
Vet - C class (pretty decent in corners, chicken shit on jumps for now)
170 lbs
My understanding of suspension is this, and should be done in this order:
Spring Rate - objective number based on rider weight
Valving - subjective based on riding type & skill. Also used to fix flaws in OEM hardware.
Clickers - fine tuning to suit speed/skill of rider
Bike in stock form felt really tall in rear. Yet OEM spring is 42 and should've been perfect for my weight. In OEM form, bike came with:
6mm preload
35mm static sag
105mm rider sag
I added the Pro Circuit linkage. That dropped the rear considerably and threw off the Spring Rate. Rider sag jumped to 140mm.
Oddly enough, I was more comfortable on the bike in the turns. And thus faster. It felt lower and I could “feel” more.
I was costantly taking shit for my setup tho from friends who are way faster than me and know more about this sorta stuff.
So I got the right spring (45n) and set it to 6mm of preload.
At 6mm of preload, this was where we were:
43mm static sag
116mm rider sag
Maybe I could’ve gone a spring stiffer? Im on a weight loss mission so I’ll make it up on that end.
I got the static & rider sag down to where it’s recommended (35/108). Went riding. Back to where I started when the bike was new. Felt too tall in the corners.
Im considering raising the sag back up. Minimal preload (6mm).
This will raise the rider sag to 116 again. Still way lower than what I liked before. But also way out of whack from what is recommended. What is the downside to this? And am I chasing the wrong gremlin?
My next attempt is to increase the rebound dampening considerably so that the bike starts to pack a little once I set it in a rut. This will give me the feel Im looking for (low rear) or am I wrong?
Any and all advice welcome.
Paw Paw
150 lbs = 9.65 bar / 140 psi
170 lbs = 10.0 bar / 146 psi
Ive been running at 10 bar. As the day goes on, the pressure drops. I tend to get more comfortable and faster. But that could simply be because of seat time.
The Shop
So what's the downside to what I was doing when rider sag was at 140mm?
And was I playing with sag when I should've been increasing the rebound dampening?
Ive tried the forks at the recommended 10.6 bar and in increments lower. It did not help what I am feeling in the rear.
The stiffer & taller things get, the further I feel from the ground (Im only 5' 9") and I begin to lose confidence/feel of the ground.
What do you think about my theory that if I increase rebound dampening in the shock I can get the low feel back?
Last question...
116mm riders sag with healthy (low amount) of preload (losing body weight every week and eventually sag numbers should get better)
or
108mm rider sag with a ton of preload
I can't honestly comment to specifics with your set up because that PC linkage is quite a bit different than stock and my understanding from reading is that PC recommends you go up at least two spring sizes when in stalling the linkage. I've never tried that link out but my gut as well as your numbers say you should need a stiffer spring. Between 108 and 116 I think is up to you, if you like 116 better in back to back tests then that's what you like and I'd say run it.
As for the shock, it like 10 out on the rebound 1 1/2 turns out on hi-speed comp and 10-12 out on low-speed comp.
As for sag, I am 160lb and like my previous huskies 98mm rider sag is awesome. At my current weight that's 32mm static sag. But any static sag between 27 and 32mm is gonna work very good with the above clicker settings.
Again, these are absolutely stock , no internal modifications.
Over the hours I tested every suggestion that was given and this is what works for me and nearly every rider who has ridden my bike from novice to true intermediate.
Peace
So...what do you think you need help with? Are you experiencing any precise problems?
6mm 35mm 105mm suggests spring rate is bang on like paw paw suggests.
Maybe slipdog will clarify, but on many shocks, the rebound works on a common circuit, so when you increase rebound damping it also increases compression damping.
I've found my fc450 a bear to get balanced, even though I suck, I can balance a bike... But I was given the wrong rate spring, plus, after 15 years of Suzuki it's wierd riding another brand that doesn't turn on a dime lol.
Slipdog also makes good points on the midvalve setting on these forks.... really thrown me through a loop.
Wow, you took it to 6 clicks out? I never wouldve thought to go that far. Now Im more confident at trying such.
Ive been quietly suspecting that was the case in my situation. After reading Slipdog's posts in this thread, Im convinced that is the issue.
I was hoping you could confirm as much. I'll be riding tomorrow and will start playing with the rebound dampening for the first time.
The current preload is a lot more than 6mm. But the other two are 35/108 at the moment. Rebound dampening is at 14 clicks out.
Rebound and Compression are not on the same clicker.
Pit Row
WP is designing and testing suspension components years ahead of ever being put on a bike.
Aftermarket suspension companies usually are slower to understand and adopt design change. It may take them many months (or years) of testing to develop specs that are required for mail order suspension tuning. On the other hand, you can design a check valve to fit the new shock relatively fast which then allows you to apply your tuning data to the more conventional circuit.
It's all about business and securing your place as a company who can keep up with changing demand. They may market the check valve as some sort of improvement, but you must ask yourself if it is such a great improvement why wouldn't WP include it as a standard design?
Gonna play around with the rebound Wednesday. I’ll report back.
Everyone had a good shock setting for a 2007 crf450, so if you copy that linkage, piston and shim stack you are halfway there.
The oems aren't stupid
Most would recommend the bladder kit. Yet even the Trax Shock doesn’t come with the bladder. I found that odd. One seems more familiar (bladder) and the other was maybe the newer tech (piston) yet not yet accustomed too?
FYI, 140mm of rider sag would probably result in excess bottoming, as you are using up half your travel just to support your weight. The bike would feel wallowy in corners and likely have excessive rebound characteristics. It would be a soft, "springy" ride.
My suggestion is to go back to the 100-105mm rider sag setting and check to see if you have 35-50mm of static sag. If the bike sags by itself more than 50mm, your spring rate is too stiff. If the bike sags less than 35mm your spring rate is too soft. It sounds backward, but that's how it works.
Once that is dialed in, work on your fork so that it sags about the same when you sit centered on the bike. You may need to change springs and/or adjust air pressure to do this. (Sorry, not sure what fork your Husky comes with.) You can also adjust the fork position in the triple clamp to change the ride height characteristics slightly. Keep in mind this will affect your handling.
Paw Paw
Go back to 42nm 105mm sag. 15R 15C 2.5HSC. Fork 148-150psi, 15C, 13R. Can go to 10R if it is hard packed.
The only thing you can change if you are not happy with it, is go to 45nm and 105mm sag. Same clickers as starting point.
Set it to 105 sag, and then test 148 or 150psi and see what you like best. When you have set that, you can also try quarter turn on preload in rear to see if it gets better or worse. Dont touch clickers until you are done here.
You can when you found a good base setting as above, try the PC linkage but you need to get decent number there also. If you run PC linkage you should go up two steps in spring, so i would say 50nm for you.
But again, remove PC linkage and go back to above.
IMO 140mm sag isnt the best idea, especially if you have lowered the rear with a linkage as well. If the bike is too tall, just get the optional lower seat. But I recon by your description you are a good height and weight for the stock bike.
If you run the bike that low in the back, front end grip will suffer and you are only 1 big bump away from a trip over the bars
When you are so far off as you are, you can easily feel that the problem is in an area where it not really is. It is like making forks softer: Starting stiff 160psi, and go closer to 150 and the fork will feel softer. When you pass a certain point, the fork will again start to feel "stiffer".
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