Static Sag v Rider Sag
Discussion
bass gt3 said:
Remember that if it's all cold, the damping will speed up as the oil warms and thins. But make sure you keep the rebound as fast as possible. I'd still wager you should be at 2 to 2 1/4 from fully in 
Maybe checkout the Dave Moss vids to see what I mean. Rebound is your most important adjustment so set it and LEAVE IT ALONE!!!
Interesting that I got a settings from Dave Moss as per so ... Maybe checkout the Dave Moss vids to see what I mean. Rebound is your most important adjustment so set it and LEAVE IT ALONE!!!
Fiddling now ...
lol Right so this is where I'm at ...
Front sag - 38mm
Rear sag - 35mm
Front rebound - 1 3/4 turns
Front comp - 1 3/4 turns
Rear rebound - 2 1/4 turns
Rear comp - 2 1/2 turns
Got to be honest it no longer feels balanced anymore although rebounds fine.
Rear feels soft as hell ... Front feels hard. So guess need to play with compression
Front sag - 38mm
Rear sag - 35mm
Front rebound - 1 3/4 turns
Front comp - 1 3/4 turns
Rear rebound - 2 1/4 turns
Rear comp - 2 1/2 turns
Got to be honest it no longer feels balanced anymore although rebounds fine.
Rear feels soft as hell ... Front feels hard. So guess need to play with compression
bass gt3 said:
Problem with a blanket approach, without proving it on your bike, you can't be 100% if it's right.
I'm not keen on the preload comment, as he seems to be using it as a means of jacking up the rear, hence the comment about the 60 profile tyre being a benefit.
Given the choice, I'd make sure the sag is right then pull the forks through a few mm if it's still slow to turn.
As for rebound, keep fiddling until it's too fast, where the bike bounces backup and rather than settle and stop, it maybe bounces again slightly. But again, if you're working on cold suspension, you can only really tell once you've ridden and everything is warm
The bike is used every day hence trying to establish a base setting from what I can tweak ... I can then warm it on way to work and tweak at each destination I'm not keen on the preload comment, as he seems to be using it as a means of jacking up the rear, hence the comment about the 60 profile tyre being a benefit.
Given the choice, I'd make sure the sag is right then pull the forks through a few mm if it's still slow to turn.
As for rebound, keep fiddling until it's too fast, where the bike bounces backup and rather than settle and stop, it maybe bounces again slightly. But again, if you're working on cold suspension, you can only really tell once you've ridden and everything is warm
bass gt3 said:
Try slowing the rear comp or opening the front comp to get better balance. Remember that compression adjustment will only affect the SPEED of change not the amount.
I've opened up the front comp ...Now ...
Rebound - 2 1/4 turns
Comp - 2 1/4 turns
Feels proper soft
It's balanced though ...
Ok so more questions despite me being done in the garage tonight.
The Fireblade runs more travel at the rear than the front therefore with this in mind would we not run more sag at the rear as opposed to the front?
Just seems odd that most superbikes run a nose down stance which would suggest less sag at rear (cos it's ride height init!?)
As first for me as all my R1's had less travel at rear than front hence me setting 30-35mm rear, 35-40mm front for road work ...
I'm on 38mm front, yet 9 turns from fully out with 1.1NM/mm springs ... Bit odd no? I'm 90kg kitted.
Thanks for all your help fella. Really interested and goes someway to supporting never trust everything you read on forums ...
The Fireblade runs more travel at the rear than the front therefore with this in mind would we not run more sag at the rear as opposed to the front?
Just seems odd that most superbikes run a nose down stance which would suggest less sag at rear (cos it's ride height init!?
) As first for me as all my R1's had less travel at rear than front hence me setting 30-35mm rear, 35-40mm front for road work ...
I'm on 38mm front, yet 9 turns from fully out with 1.1NM/mm springs ... Bit odd no? I'm 90kg kitted.
Thanks for all your help fella. Really interested and goes someway to supporting never trust everything you read on forums ...
bass gt3 said:
Cool,
Now it might be a tad soft, (we've been setting it up stone cold so it may get softer) but if you feel it's too soft once warmed up, add compression damping (clockwise) to front AND back in the same amount. DON'T touch the rebound unless it's too fast once warm.
However, if the suspension is compliant it'll ride much nicer and get better traction rather than if it feels all stiff and heavily controlled.
Ultimately, there's no magic bullet. You will like what you like and it might not be this. However, if you let the suspension do its job, the bike becomes much better to ride.
I did this with a good racer 2 weeks ago and despite his scepticism he ended up 3 seconds a lap quicker on a bike he felt was "looser'. Bottom line was the tyres had much better traction, and once he got used to the slight squirming under power, the grip off corners was much better, hence the massive drop in times
Ok, so play with compression only ... Got ya! Now it might be a tad soft, (we've been setting it up stone cold so it may get softer) but if you feel it's too soft once warmed up, add compression damping (clockwise) to front AND back in the same amount. DON'T touch the rebound unless it's too fast once warm.
However, if the suspension is compliant it'll ride much nicer and get better traction rather than if it feels all stiff and heavily controlled.
Ultimately, there's no magic bullet. You will like what you like and it might not be this. However, if you let the suspension do its job, the bike becomes much better to ride.
I did this with a good racer 2 weeks ago and despite his scepticism he ended up 3 seconds a lap quicker on a bike he felt was "looser'. Bottom line was the tyres had much better traction, and once he got used to the slight squirming under power, the grip off corners was much better, hence the massive drop in times
... Half a turn at a time?But yep the bike is pretty much on standard settings now ignoring preload !
I should have just done that first!
Mr OCD said:
I'm on 38mm front, yet 9 turns from fully out with 1.1NM/mm springs ... Bit odd no? I'm 90kg kitted.
suspension wizard said:
Indeed, which is why I'd question the quoted value. But there's other factors possibly in play. But 38mm on a road bike is on the firm side of good considering the target is around 1/3rd of total stroke as sag.
Afternoon 
Just had a look round online...
RaceTech are reporting the front spring rates as 1.040kg/mm standard...
Not as stiff as originally thought... although spring rates seem to differ looking around on line! So I've dropped both KAIS and K-Tech an email this morning.
Initial impressions on riding the bike today... I'm not convinced it is as soft as expected. Feels rather compliant but I haven't pushed the bike hard enough to judge properly. It does however feel as though the rear is sitting a little low when I sit on it fully kitted. Or possibly the front is a little high...
bass gt3 said:
Afternoon,
If you really feel like the front is a tad high, try taking2 or 3 turns of front preload out. That'll drop the front a tad.
As for the perceived softness, they never are as soft as you'd think.
But once you have the front height where you're comfortable, try dialling in a tiny (quarter turn) of compression front or back and se how it feels. But now's the point where you need to start making notes and only change ONE thing at a time.
But that will increase rider sag to over 40mm?If you really feel like the front is a tad high, try taking2 or 3 turns of front preload out. That'll drop the front a tad.
As for the perceived softness, they never are as soft as you'd think.
But once you have the front height where you're comfortable, try dialling in a tiny (quarter turn) of compression front or back and se how it feels. But now's the point where you need to start making notes and only change ONE thing at a time.
IIRC 7 turns from fully out (soft) is 42mm with me on it ... standard is 4 turns from fully out (soft) (out of 15)...
After reading back through this thread last night one question I did raise is given the preload has no affect on spring rate, i.e. preload changes suspension height not stiffness. Why does increasing preload reduce sag?
RACETECH
FRONT FORK SPRINGS
Recommended Fork Spring Rate: 1.007 kg/mm (use closest available)
Stock Fork Spring Rate: 1.040 kg/mm(stock)
Something is wrong ... got to be. Fork springs on the bike should be perfect (unless they have been changed) for my weight so why am I needing so much preload to get the sag in the right area?
I assume I'm measuring it correctly?!!
Fork seal/lip to base of fork?
FRONT FORK SPRINGS
Recommended Fork Spring Rate: 1.007 kg/mm (use closest available)
Stock Fork Spring Rate: 1.040 kg/mm(stock)
Something is wrong ... got to be. Fork springs on the bike should be perfect (unless they have been changed) for my weight so why am I needing so much preload to get the sag in the right area?
I assume I'm measuring it correctly?!!
Fork seal/lip to base of fork?
bass gt3 said:
It's an illusion If you wound full preload in, you see your total stroke was longer as the preload is overpowering the neutral spring. So the spring will always sag the same amount for a given weight. Preload just moves the range up a bit. It's why springs come in half newton increments, otherwise if preload was able to cover a broad range of springs, there'd be no need for such fine increments.
But given that we're stuck with the springs we have, we can't actually change true sag. The preload will only adjust ride height so it's ok to take a couple of turns out to lower the front. Now you can add a smidge of compression in the front to slow the forks a bit.
Thanks for the explanation... If you wound full preload in, you see your total stroke was longer as the preload is overpowering the neutral spring. So the spring will always sag the same amount for a given weight. Preload just moves the range up a bit. It's why springs come in half newton increments, otherwise if preload was able to cover a broad range of springs, there'd be no need for such fine increments.But given that we're stuck with the springs we have, we can't actually change true sag. The preload will only adjust ride height so it's ok to take a couple of turns out to lower the front. Now you can add a smidge of compression in the front to slow the forks a bit.
I'm actually considering changing the springs if I need to do so as I plan to keep the bike a couple of years so want it riding well. As always it is a compromise... the standard Fireblade suspension is supposed to be very good and as a road bike for 95% of the time commuting spending thousand of pounds on suspension upgrades just isn't justified.
Don't mind spending a couple hundred quid on springs though...
I will change the preload to 7 turns from soft that puts is back to pretty much how it was!
So we've come round full circle...
fergus said:
check out his site, it's got some really interesting stuff on it : http://feelthetrack.com/free-vidoes/setting-sag-2/
you could do a lot worse than to buy this book: http://www.amazon.co.uk/Suspension-Tuning-Handling... It's very easy to read and explains things in an accessible way.
Cheers for info ... Just bought that book ... Genuinely finding suspension very interesting you could do a lot worse than to buy this book: http://www.amazon.co.uk/Suspension-Tuning-Handling... It's very easy to read and explains things in an accessible way.
Edited by fergus on Monday 30th March 14:39
bass gt3 said:
Good man!
It does get interesting, especially when clown wander around skinning 40 quid for twiddling a couple of adjusters for no apparent improvement.
Fact is, the basics are too so difficult to fathom, and it's good to know how it all functions.
It does ... I like things to be 'right' and suspension is the only thing I've not fully grasped in detail when it comes to bikes. It does get interesting, especially when clown wander around skinning 40 quid for twiddling a couple of adjusters for no apparent improvement.
Fact is, the basics are too so difficult to fathom, and it's good to know how it all functions.
Just got a reply from Maxton who advise both front springs and rear shock springs are a little soft so want to sell me springs, valving and a new rear shock without actually answering my questions.
Yeah ok ... Not.
bass gt3 said:
You seem surprised
I know, I know ... I shouldn't be ... I just want to be provided with information and helped to achieve my target.I accept that possible new springs and service work are required which means spending money and that is fine ... But I want more than just parting with cash...
In meantime I want to understand what I've got and how I can make it work to best of my ability and until I've done so I aint spending a penny
No fancy ohlins, springs, valve kits are going to mean owt if it's not working how it's designed due to poor setup!
Already started reading... and watching Dave Moss videos.
So far I've learnt ...
Once rebound is set properly you shouldn't need to mess about with it, but it is important the sag / spring rates are correct first before fiddling.
Compression is the one to fiddle with as you'd run a bit more on the track to the street obviously... I'm interested to know why the front compression was pretty much fully out on the blade... for a plush ride I guess... ?
All pretty simple stuff TBH but I've been more interested in having the skill to apply it and know how the bike should respond to adjustments. Even knowing how to 'bounce' the bike properly has made a BIG difference.
I used to use the bit behind the tank cap but on the blade this isn't a great idea as it's a plastic cover which flexes... Dave Moss advises using the seat AND the bar to bounce the bike - something I will be trying tonight.
Bike is off the road for a couple days due to the pissing weather so I'm going to buggering about with the suspension for practical experience and turn into a book nerd
Mr Moss advises 30-35mm rear, 35-40mm front rider sag for the street.
STREET!? - Been watching too many american videos!!!
So far I've learnt ...
Once rebound is set properly you shouldn't need to mess about with it, but it is important the sag / spring rates are correct first before fiddling.
Compression is the one to fiddle with as you'd run a bit more on the track to the street obviously... I'm interested to know why the front compression was pretty much fully out on the blade... for a plush ride I guess... ?
All pretty simple stuff TBH but I've been more interested in having the skill to apply it and know how the bike should respond to adjustments. Even knowing how to 'bounce' the bike properly has made a BIG difference.
I used to use the bit behind the tank cap but on the blade this isn't a great idea as it's a plastic cover which flexes... Dave Moss advises using the seat AND the bar to bounce the bike - something I will be trying tonight.
Bike is off the road for a couple days due to the pissing weather so I'm going to buggering about with the suspension for practical experience and turn into a book nerd
Mr Moss advises 30-35mm rear, 35-40mm front rider sag for the street.
STREET!? - Been watching too many american videos!!!
fergus said:
All the damping does is control the rate of spring movement. If the spring rate is not correct, the damping will either be doing more work than it needs to, or will be ineffective.
This is the reason why getting the static then dynamic (rider) sag is so important to evaluate whether your starting point is good. If not, then go get some new springs and repeat the process....
Agreed ... Hence will be checking both static and dynamic sag. At present its pretty close with 38mm front, 35mm rear and roughly middle of preload settings so the springs are pretty close ... This is the reason why getting the static then dynamic (rider) sag is so important to evaluate whether your starting point is good. If not, then go get some new springs and repeat the process....
If anything slightly stiffer fork springs be a good idea but I want to see how I can get on first with current springs before I start messing ...
What's a good static sag value for forks and shock on a sportsbike?
I'm reading into how preload affects ride height at present and ideally you should increase both ends the same amount to keep the bike height / geometry the same ...
But that geometry will change once you apply weight to the forks / shock (I.e. Sit on it ... ) ... So do I need the ride height spec from Honda?
Am I thinking about this too much lol
I'm reading into how preload affects ride height at present and ideally you should increase both ends the same amount to keep the bike height / geometry the same ...
But that geometry will change once you apply weight to the forks / shock (I.e. Sit on it ... ) ... So do I need the ride height spec from Honda?
Am I thinking about this too much
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