Evo 100 wilbers for springs

[Luddite]

Originally Posted by dwilsonguitars

There's not much point in the needle valves which limits there function but with every thing set half way rebound and compression feel great

You're right about the bluntness of the original adjusters, which probably explains why you can't feel much difference between maximum and minimum.



These are the K-tech replacements and, while you can't see the compression needles, the rebound needles are clearly a lot sharper and give a much larger range of adjustment. (Even I can feel the difference!)

[chris.p]

Originally Posted by Luddite

You're right about the bluntness of the original adjusters, which probably explains why you can't feel much difference between maximum and minimum.



These are the K-tech replacements and, while you can't see the compression needles, the rebound needles are clearly a lot sharper and give a much larger range of adjustment. (Even I can feel the difference!)

Yep, thats the kit Chris @ K-Tech put in my forks, he was able to strip the cartridges and put there parts inc springs in, cost was then £550, so will have gone up by now i guess.
The difference was night & day

http://www.ukmonster.co.uk/monster/s...ront+forks+evo

[chris.p]

Originally Posted by Luddite

I still think it's worth checking the static sag in conjunction with dynamic sag. If the static sag is insufficient, you could experience excessive topping-out even if your dynamic sag is within the recommended range.

This is what happened when I first fitted an Öhlins DU737 with a 115N/mm spring to my Evo. The sag figures recommended by Öhlins were minimum 10mm static and 25-40mm dynamic. Out of the box, there was virtually zero or 1-2mm static sag but I didn't adjust it because the dynamic sag with me on board was within the recommended range (about 26mm). The ride was not very smooth and I subsequently backed off the preload to give 10mm of static sag while still staying within the recommended dynamic sag range, which improved the ride considerably. I eventually fitted a softer 105/mm spring but still set the same static sag with slightly more dynamic sag, which now suits me perfectly.

Some (much) more knowledgeable people than me have given the following advice on static sag:

This from Niall Mackenzie in 2003:
https://www.visordown.com/features/g...kes-suspension

"If there's no difference, (between shock fully extended and then with the weight of the bike*), you have no sag and you're in trouble. Your bike will be on its nose braking, the rear end will be hopping and pattering, and if you get back on the gas hard out of a corner it'll probably highside you ."

*my words.

Then, from Tony Foale's bible "Motorcycle handling and chassis design"



That diagram graphically illustrates the "hopping and pattering" that Mackenzie described earlier.

Totally agree you must have the correct static sag.

[Mossleymonster]

Originally Posted by Uncle Bob

Funnily enough, watching videos online last night (as per the suggestion above) I found myself wondering what the real point was of measuring static sag?

I get that it's an indicator of how firm the suspension setup is in the first place, but after that it's all dictated by rider weight (mostly)...

Absolutely, if you are in any doubt. Have a word with Daz at http://mickgardnerracing.com/

[Mossleymonster]

Originally Posted by Luddite

Glad it's sorted now. Sounds like you had a lucky escape with that tyre. Seems like the bike's been fighting you since you got it what with the front wheel being the wrong way round and the seized shock bolt (and bodged forks!). But I think you've beaten it into submission now!

I don't beat anything into submission.

[350TSS]

Luddite - is there another graph? (9.41) as I could not follow the logic from the words and only one graph (maybe I really am thick). If so please could you put it up as well.

[Uncle Bob]

Originally Posted by Luddite

I still think it's worth checking the static sag in conjunction with dynamic sag. If the static sag is insufficient, you could experience excessive topping-out even if your dynamic sag is within the recommended range.

This is what happened when I first fitted an Öhlins DU737 with a 115N/mm spring to my Evo. The sag figures recommended by Öhlins were minimum 10mm static and 25-40mm dynamic. Out of the box, there was virtually zero or 1-2mm static sag but I didn't adjust it because the dynamic sag with me on board was within the recommended range (about 26mm). The ride was not very smooth and I subsequently backed off the preload to give 10mm of static sag while still staying within the recommended dynamic sag range.

Erm, what's the difference? I mean, all you've actually done is set the rider sag to 36mm, no?

What does it matter what the bike suspension does without a rider on it?! Why is it even relevant? That's what I still don't get.

[Luddite]

Yes, sorry, Rich, as I was just referring to the rear wheel, I included only the first graph since the second one described the front wheel's behaviour during acceleration. However, for completeness, here it is with the accompanying notes:



Oh, and as for being thick - having seen what you've achieved in your rebuild thread, I don't think that's an option. I mean, if it was, what does that make the rest of us?!?

[chris.p]

Originally Posted by Uncle Bob

Erm, what's the difference? I mean, all you've actually done is set the rider sag to 36mm, no?

What does it matter what the bike suspension does without a rider on it?! Why is it even relevant? That's what I still don't get.

Simples really, if you have no static sag your bike will top out with a Bang in some instances, for example if you hit a small crest at speed, your suspension will top out, not good.

[Luddite]

Originally Posted by Uncle Bob

Erm, what's the difference? I mean, all you've actually done is set the rider sag to 36mm, no?

Yes, but in increasing the dynamic sag, it also resulted in adding static sag that hadn't existed before.

Originally Posted by Uncle Bob

What does it matter what the bike suspension does without a rider on it?! Why is it even relevant? That's what I still don't get.

As for its relevance, I can't do any better than quote the two bullet points from Tony Foale's explanations above:

With insufficient static sag (my words):

"• The static loaded position of the suspension is closer to the rebound stops, and so there is less suspension movement available before topping-out. So that occurs more often.
• The preload force means that when the suspension does top-out, it does so in a harder fashion."

Niall Mackenzie describes what that feels like to the rider and his experience tallies exactly with the recorded behaviour of the wheel in those circumstances as shown in Tony Foale's graph.

As I mentioned when I was describing my own experience, it's quite possible to set your dynamic sag within the recommended range and yet still have no or minimal static sag so I always now check the two and make sure they are both within their recommended ranges.

I would add that the same amount of factory set preload that gave me zero static sag on the Öhlins DU737 with the 115N/mm spring, gave the perfect static sag with a 105N/mm spring.

Not sure I can add any more so I hope that helps.

[Luddite]

Originally Posted by chris.p

Simples really, if you have no static sag your bike will top out with a Bang in some instances, for example if you hit a small crest at speed, your suspension will top out, not good.

Well done, Chris! You managed to explain in four lines what I took half-a-page to achieve!

I'm often accused of being a windbag - here's the proof!

[chris.p]

Originally Posted by Luddite

Well done, Chris! You managed to explain in four lines what I took half-a-page to achieve!

I'm often accused of being a windbag - here's the proof!

Bless you kind sir

[Mossleymonster]

Originally Posted by Luddite

Yes, but in increasing the dynamic sag, it also resulted in adding static sag that hadn't existed before.



As for its relevance, I can't do any better than quote the two bullet points from Tony Foale's explanations above:

With insufficient static sag (my words):

"• The static loaded position of the suspension is closer to the rebound stops, and so there is less suspension movement available before topping-out. So that occurs more often.
• The preload force means that when the suspension does top-out, it does so in a harder fashion."

Niall Mackenzie describes what that feels like to the rider and his experience tallies exactly with the recorded behaviour of the wheel in those circumstances as shown in Tony Foale's graph.

As I mentioned when I was describing my own experience, it's quite possible to set your dynamic sag within the recommended range and yet still have no or minimal static sag so I always now check the two and make sure they are both within their recommended ranges.

I would add that the same amount of factory set preload that gave me zero static sag on the Öhlins DU737 with the 115N/mm spring, gave the perfect static sag with a 105N/mm spring.

Not sure I can add any more so I hope that helps.

Just for my own satisfaction I'm going to pass all of this on to Daz at MGR and see what he thinks. He is Ohlins trained.

Originally Posted by Luddite

You're right about the bluntness of the original adjusters, which probably explains why you can't feel much difference between maximum and minimum.



These are the K-tech replacements and, while you can't see the compression needles, the rebound needles are clearly a lot sharper and give a much larger range of adjustment. (Even I can feel the difference!)

Yes it was very interesting bouncing up and down on just one fork leg feeling the effects of turning adjusters fully in and fully out , suppose you can't get it to wrong with such limited adjustment .just realised my phone has predictive text and changed a lot of my words , well done chaps for even understanding what I've said !
Dry day here in Northumberland so off out on her to enjoy the smooth ride 😁

[Uncle Bob]

Originally Posted by chris.p

Simples really, if you have no static sag your bike will top out with a Bang in some instances, for example if you hit a small crest at speed, your suspension will top out, not good.

With respect, I think you might be incorrect there. Static sag alone will not stop the suspension topping out. The suspension can still top out regardless of what your preload is set to, it's not a 'top out prevention device'.

One of the reasons for setting 'sag' is so that with your weight on the bike the forks\shock have enough travel\range to decompress as well as compress. But they can both still technically top out.

If preload, and therefore (rider) sag, is set correctly, there will be enough travel in the fork\shock for the suspension to move up and down, then compression\rebound damping controls the rate at which that happens.

If all that is setup properly (in combination with the correct spring) then top out\bottom out shouldn't happen, but none of that really has anything to do with static sag. As far as I can tell anyway.