[littleowl]

Sorry a bit long lol. As you might have gathered I am no technical expert but trying to understand about sag and suspension, since having some Andreani forks fitted.

I'm quite short and originally I had my bike seat lowered by maybe around an inch or so, then had a Nitron shock fitted which has also been shortened slightly - I asked them to shorten it as much as possible without affecting the handling of the bike. I believe this to be around 10mm on the shock to give me around 30mm (just over 1 inch) height reduction.

This was all fine and the bike handled as well as it ever did, but the improvement of the rear shock seemed to highlight the harsher front suspension (perhaps all the more so because I have arthritis in hands and wrists).

So after reading many good reports I took the plunge and ordered some Andreani cartridges. These were fitted into my bike at exactly the same position as the stock forks, but on riding the bike and expecting immediate improvement, I was rather dismayed - it felt heavy and high, a bit unwieldy to ride, and wanting to stand up in bends. I spoke to FTR Suspension (people who supplied the kit) and was told the first thing I should do should be to lower the front of the bike as the geometry would be out.

Due to the position of the speedo the forks could only be raised about 8-9mm which is way less than the rear has been lowered, but after this was done the bike then felt like it had gone the other way - light and skittish at the front and wanting to tip into bends - which confused me as I've read that if you lower the rear, the front should be lowered to exactly the same amount?? :icon_scratch:

Anyhow, I have also been reading about the importance of sag. We measured the sag on my bike today and the rear seems to have a lot more than is recommended, although before I had the forks replaced I didn't find this to be a problem whatsoever; there is no bottoming out and the ride was comfortable. But if I increase the preload to accommodate the correct sag, it will raise the bike up again which is what I don't want!

Front sag didn't seem to be too bad (although still a bit more than recommended) and the forks have now been dropped again by 4mm. Haven't yet tried the bike due to no more daylight.

I'm hoping that eventually I will be able to adjust settings to my liking, but as yet the upgraded forks have yet to earn their huge cost!

I've been reading loads on suspension and am just confusing myself further. Most stress on the importance of correct sag as a base line, but I feel if I adjust the rear via preload it will raise my bike to a level I'm not happy with - and it was fine before the forks were replaced.

I'm also confused as to why my bike was suddenly so much harder to ride once the new forks were installed - whereas it wasn't before? I'm just hoping that I can ultimately get it back to somewhere close to as it was before

Any advice/info, just to confuse me further? :huh:

 

[TC3]

I think it may be a good idea to pay a suspension guru to adjust your bike to how you want?

 

[The Duchess of Desmo]

Revs in Halesowen are suspension experts. I would head there if you can't sort it yourself.

 

[Graeme]

You mention about having rear shock lowered. I had a maxton shock fitted and as I recall they advised the shock to be slightly longer thus raising height slightly to improve (in their opinion) the handling of the bike into corners. All I can say is that the performance of the bike's suspension when dealing with corners now exceeds my requirements, which I believe is how it should be . It might be you have you inadvertently affected the bikes handling by lowering the bike at the rear. Again, as others suggest, sounds like this needs a suspension specialist to work out what to do.

 

[The Duchess of Desmo]

Revs Suspension

 

[c turner]

Gill,

You need to get back as close as possible to original.

Our bikes were set up with certain specific parameters. Too much deviation from those limits can create havoc and untold problems.

Geometry and physics can be a real bitch!

Cliff

 

[littleowl]

Yes I am wanting to get back to as close as possible to normal - although as I said the shortened shock did not cause any issue to the handling with the original forks - it's just been since the Andreani have gone in. I didn't realise how much of a difference a few millimetres causes!

I may have a word with Maxton as they are not too far from me?

 

[Simon Audi]

Gill

With the SAG now set - I suggest you ride it today and let us know how it goes

Maybe the lower rear as was with softer rear (less preload than needed to get SAG correct) had lowered the rear to a point that perhaps the standard front shocks were doing very little - and the rear was doing all the work.

But as you say the normal thing to do would be to lower front to match back so you do not adjust the geometry of the bike suspension.

Maybe the new Andreati inserts and springs - despite being lighter than the standard replacement springs - were still heavier than the standard front springs - which in effect raise the front even more

As you do not post the numbers for your Free and Static SAG - its difficult to say.

Let us know how you get on after your ride.

 

[greer]

Gill,

Yep, try it with the forks only about 4mm in the clamps. Any little bit of adjustment to fork height makes a greater impact on the handling. I wish the FTR folks had taken time to explain things a little better, saved you a lot of time and frustration. Good luck and let us know how it goes with 4mm.

Sarah

 

[littleowl]

Ok well I had the chance to give the bike a good ride today, it is definitely way better having the forks dropped back a little towards their original position. The problem with having front and rear by two different companies is that neither are fully au fait with what the other is doing - but I feel I got some good advice from Nitron who said to basically keep everything as it was, start by altering the preload and if that doesn't work then to alter the forks by very small amounts (no more than 2mm at a time). I may well drop the forks (raise the front) by another 2mm and go from there. I feel I'm very nearly there, once I've got the handling right then I'll tweak the damping.

I'm amazed at how much a tiny amount of adjustment - specifically at the front - can affect the bike's handling! But all good learning experience for me

 

[The Duchess of Desmo]

Great news Gill. We missed seeing you at Ponderosa!

 

[greer]

Good!

Sarah

 

[littleowl]

Nitron also said that they make the rear shock to suit the Scrambler stock forks - so that's obviously why upgraded forks like mine have upset the applecart so to speak. Perhaps a reason to have the same company do both front and rear, although I'm sure a fair few have different front/rear setups like me, as neither Nitron nor Ohlins do both. No problems if you know what you are doing! (unlike me )

 

[c turner]

It's a delicate balance - hard to do one end without doing the other.

Best to do both to avoid discord.

I replaced a rear shock by itself once . It was supposed to be the "Next Great Thing"... It bounced me into the nearest tree.

I only learn the hard way, I suppose.

Cliff

 

[The Duchess of Desmo]

Gill how is the suspension now?

 

[Smifff]

When I fitted the after market shocks they each lifted the rear an amount which seriously affected the handling and "feel" of the front.

I found that by adjusting the height of the rear there was a tipping point where it went from terrible back to normal again, there were only millimeters in it.

The bike is particularly sensitive to changes in ride height front to rear.

 

[Desmoduke]

I fitted the M Shock and immediately found it good and no difference in ride height although my rider weight is 90kgs and I had the beefier spring. For me it worked. We will see how the Matris fork cartridges work when they arrive and what challenges they bring to the party.

 

[Smifff]

My M Shock has been great too, the issue for me was only that the pre load was wound up a bit too far. When I wound it off a bit it lowered the rear and the front settled nicely.

To be clear,

M Shock, pre load was wound up too much but spring is spot on.
Ohlins, spring too firm and lifted the rear too much. I could adjust the height but the spring is still too firm.
Nitron, spring too firm and lifted the rear too much. I could adjust the height but the spring was still too firm.

My point is that the bike is sensitive to ride height changes.

 

[1963wak]

I have just fitted a 97.5kgcm straight spring to my standard rear shock and it seems to have cured the crap rear suspension. all for a dizzy £10....

 

[The Duchess of Desmo]

I have just fitted a 97.5kgcm straight spring to my standard rear shock and it seems to have cured the crap rear suspension. all for a dizzy £10....

If that's worked you are clever and good at saving money !