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Discussion Starter #1
Hi All!

I'm trying to set the sag on my 2012 250 EXC-F...

I weigh 110kg + 8kg of gear (Gear / clothing + trail riding spares - incl. spare kitchen sink)

My rear spring is 76nm, I purchased this to replace the 66nm that was on the bike when I got it - thinking that it would be stiff enough

I can only get the manual's recommended 115mm of riding sag by using up all of the available preload AND measured standing on the pegs, not sitting down...

Question 1:
Am right that more preload = less usable suspension travel?

Question 2:
Would it be better to have more travel, use less of the preload and have incorrect sag? I.e. Is using the full range of preload adjustment 'bad'?

Question 3:
The manual suggests measuring sag sitting down - I won't get anywhere near the book values with a sitting measurement, as said, even standing is tough to get near it

Question 4:
Are there even stiffer springs available, where would I get one if that is the only way to get the sag right.

This is where I've stopped, this gives me about 125mm of rider sag, and uses almost all of the preload, but not quite:

 

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I can see your trouble. You've replaced a 76nm spring with a 76nm spring.
 

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Whats the static sag? That needs to be within range too.
 

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Discussion Starter #5
If I remove my tail pack and fender bag, and re-measure the static sag, I get 28mm which is outside of the book's 33-35...

Am I correct that the static sag should be measured with nothing on the bike - i.e. luggage removed?

I suppose that what I'm asking is for opinions, and we know that these are abundant on all forums :D

It's pretty clear that I need to go one or two spring sizes bigger. I don't want to do that just at the moment.

So in the meantime - is it better to have incorrect sag, but only 3/4 of the preload used up? Or is it better to have almost the correct sag - but have used up all of the pre-load?
 

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You need an 85 or 90nm spring. Probably 90. You won't get anywhere near the right sag numbers with that spring.

If no choice, it's better to have the correct rider sag so that the bike will corner safely but you'll pay for it by the rear being harsh and kicking a bit on rough stuff.

I'm 110kg too so I've been there. Honestly, just get the right spring and think about doing the fronts too.
 

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Discussion Starter #7
You need an 85 or 90nm spring. Probably 90. You won't get anywhere near the right sag numbers with that spring.

I'm 110kg too so I've been there. Honestly, just get the right spring and think about doing the fronts too.
Thanks Al_Orange that makes sense. I think the shop just sold me the stiffest spring that they had in stock on the day that I asked and at the time I never expected to be carrying so much weight in tools and spares

The forks are definitely on the to-do list, but I'm going to take them to see a professional (psychiatrist); so I might as well get them to sort out the back while I'm there
 

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Just send a message to Brokenlegs on here, he will sort you out and is the best value. Your rear spring is way too light for your weight, as are your fork springs. you cant do one without doing the other. Have a chat to him.
 

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I'm a similar weight (107kg) and I have a 90 at the back and 44 at the front, You definately need stronger springs. Take everyone's advice replace the springs at the very least but as Mike said get in touch with Brokenlegs and get a revalve at the same time.
 

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I'm 100kg without gear and have a stiffer rear spring ( off Brokenlegs ) its a linkage bike so different numbers to PDS but the bike just sits much better and can achieve the recommended rider sag. With mine being an XC the fronts are slightly stiffer spring rate too, which helps.
 

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The thing is if you meet Brokenlegs it'll probably be at greggs or a cake shop so a 90 will be out of the question after you deplete greggs and set off for a kebab shop!
 

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on my 450 i was 90kg and went up 2 weights on the rear so i reckon you need to go up one or two weights. if you use up the preload the whole way the shock works is compromised. but unless you are struggling on the lanes or racing/practice days then don't bother. if you do go for the correct weight do the fronts too and maybe a re-valve too (front and rear).
 

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Discussion Starter #15
Thanks RedBikeJohn - it's good to get confirmation that running max preload is not a good scenario, with an explanation of why.

What you're suggesting sounds right for me. I.E. I was having problems keeping the back end in line with the original 66nm spring ; and it's been okay since moving to the 76nm - what sparked this was the addition of more weight in gear, tools and spares...

I'm going to wind the preload back to the 50% point and be done with it for now.

When I get a gap where I don't mind having the bike out of action for a while then I'll get it sorted by brokenlegs et al.
 

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at your weight, with a 76 spring, the bike won't handle, never mind tail pack or anything else. I'm around the same weight, have a 90 spring and a 4.8 fork springs and its perfect (brokenlegs did mine)
 

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not sure which will be worse. the shock sitting too low in its stroke (damping all out) or sitting correct for rider sag but pre-load wound right up.
personally i'd keep the pre-load wound on. if the bike sits too low on the rear the front end geometry will be all out so it'll compound the iffy feeling.
with extra pre-load i think upping both the damping might help the shock fight against the spring - but just a guess.
 

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Discussion Starter #18
i think upping both the damping might help the shock fight against the spring - but just a guess.
I'm going to go out and ride it later this afternoon, I'll tweak the damping as I go, The proof is in the pudding - I have a nice whooped out lane near me that I can ride along after each adjustment to try and keep the conditions consistent

The proof is in the pudding - or at least this scenario is proof that eating the pudding will complicate your suspension setup!!!
 

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Look it's simple, you spent all that money on a bike but won't invest the last 150 on correct springs, what's the fuckin point of having a bike that can be brilliant but letting it behave like a C90?might as well not bother, you've been advised several times you need heavier front and rear to cope with the heavier middle, but keep saying I'll see how I get on.(do they have an emoji for slap head)
 

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Look it's simple, you spent all that money on a bike but won't invest the last 150 on correct springs, what's the fuckin point of having a bike that can be brilliant but letting it behave like a C90?might as well not bother, you've been advised several times you need heavier front and rear to cope with the heavier middle, but keep saying I'll see how I get on.(do they have an emoji for slap head)

wot he sed ^^^^ :)

springs are the 1st thing to get right with suspension.

pull yer finger out and get it sorted, after you'll wonder why you fucked about for so long.
 
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