Suspension Guru's

Tuono1961

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Chaps

On medium to firm acceleration I have noticed a tendency for the rear wheel to skip a bit too much when going over bumps/ undulations in the road.

What bit do I need to fiddle with to dial this out:confused:
 
Soften the preload off, then see if you need to tweak the rebound:thumb
 
Chaps

On medium to firm acceleration I have noticed a tendency for the rear wheel to skip a bit too much when going over bumps/ undulations in the road.

What bit do I need to fiddle with to dial this out:confused:

As that could be caused by either too much or too little damping the easiest way is to drive backwards and forwards over the same road and adjust the damping one way then the other. Helps if the sag is correct first but lord knows what an odd bike like a GS should have the sag set to. :nenau

Being on the heavy side I set my preload to max and turned the clicker until it felt controlled. However remember that plush does not necessarily mean best traction.
 
Winding back the twistgrip bit would prevent it. Other than that, a wheel skipping off bumps is usually caused by too much compression damping. There's only one damping adjustment on the shock, so assuming you dont have ESA, try tweaking the screw in the base of the shock but bear in mind there's not a great deal of difference from 'hard' to 'soft' (compared to therange of adjustment in an aftermarket item). I'd start from full soft and increase the damping until the rear end just stops wallowing after encountering a large bump. Don't miracles though.
 
Guys it really isn't as simple as, if it skips from a bump it must be X. Therefore set the sag by measuring and set damping by testing. A quick and dirty way to get in the ball park is to bounce on the suspension and adjust the damping so that the seat returns without overshoot or oscillation. Start too soft and bouncy and just eliminate the oscillations. But!!! The oscillations are small so watch closely and feel for them with your hand on the seat as it returns. Then go and test back and forth over a suitable road.
 
soften everything off, then increase them both one at a time till you're happy.

think motocross - full travel - well controlled.
 
soften everything off, then increase them both one at a time till you're happy.

think motocross - full travel - well controlled.

Exactly:thumb..perfect suspension is a black art but preventing a heavy bike from skipping under accelaration over bumps, isn't.
I also use the technique of pushing down on the rear to feel the return but a GS isn't quite as responsive with less travel.
 
Chaps

On medium to firm acceleration I have noticed a tendency for the rear wheel to skip a bit too much when going over bumps/ undulations in the road.

What bit do I need to fiddle with to dial this out:confused:

You need more pies in your panniers:thumb2
 
Chaps

On medium to firm acceleration I have noticed a tendency for the rear wheel to skip a bit too much when going over bumps/ undulations in the road.

What bit do I need to fiddle with to dial this out:confused:

The throttle :nenau

Or Ohllins :thumb
 
So far then it's

Sag
Rebound
Compression
Pre load
Not fat enough
Riding too fast
Wrong shock absorber


Oooh, I do like a straight answer:blast

Think I'll start with winding off the preload as that's the easiest option and take it from there:beerjug:
 
Chaps

On medium to firm acceleration I have noticed a tendency for the rear wheel to skip a bit too much when going over bumps/ undulations in the road.

What bit do I need to fiddle with to dial this out:confused:

Not sure you can dial this out - are you new to shaft drive ? It's nowhere near as compliant as a conventional setup with chain and sprockets although they have got a lot better over time. I have Ohlins which help but there's a limit to what's possible - I also ran a Tuono which was in a different league as far as suspension/ handling were concerned. Think Land Rover :D
 
Back the preload and damper right off. Adjust preload first until you have just 25mm of sag. Then adjust damper until the bike bounces once on the rear.

Works for me.....
 
I also ran a Tuono which was in a different league as far as suspension/ handling were concerned. :D

You're right, my T is also the full ohlin's jobbie as well. I've probably been a bit spoilt on the suspenders front:D
 
You're right, my T is also the full ohlin's jobbie as well. I've probably been a bit spoilt on the suspenders front:D

The anwser is just get on the bike ride it and dont worry about it, its called character sir, I think you will find they all do it sir, it will ride up with wear sir !!!! ;-)
 
You're right, my T is also the full ohlin's jobbie as well. I've probably been a bit spoilt on the suspenders front:D

I had ohlins on my T and also on the GS and it's still chalk and cheese. I'm no expert but I think the greater unsprung mass caused by the paralever suspension/drive shaft is the main reason for the relatively poor ride compared to a well sorted sports bike. I find the choppy ride under power/ over bumps is jsut something you have to live with. Playing with the suspension might help but make a note of the original settings as you may make it worse :rob
 
Back the preload and damper right off. Adjust preload first until you have just 25mm of sag. Then adjust damper until the bike bounces once on the rear.

Works for me.....

Static bike sag?
On a sports bike that could be rider sag for a track but on a GS I assume it's static but hey they're funny bikes :nenau
 
Static bike sag?
On a sports bike that could be rider sag for a track but on a GS I assume it's static but hey they're funny bikes :nenau

Most sports bikes should have about 10-20mm, 25mm would be generous for a sportsbike on the road.

Still have no idea what sort of sag a GS should have :nenau

Think it makes far less odds with these types of bike :nenau
 
According to RaceTech 25mm would not be generous for rider sag, but very generous for free sag:
http://www.racetech.com/page.aspx?id=30&menuid=93#3

My sports bike runs 8mm free sag at the rear and 24mm at the front as well as being raised at the rear. But ... that's possibly because I'm large and heavy which I'm led to believe tends to put too much weight on the rear so the suspension tuner is probably trying to compensate for that and shift some forward.
 
The term Static sag normally applies to a static bike i.e. no rider.

You should be looking for about 1/3rd total travel used with rider on board, so 15mm static would hopefully be 35-45mm with rider out of a total 120mm travel typically found on a sportsbike.

On track under 10mm is common, 125gp bikes tend to run at zero sag, supersport / superbikes typically under 10mm, but the road is quite different.

I have also found regardless of theoretical ideals sometimes a bike feels nicer a slightly out of spec, I like a quite sporty setup, but my ZZR14 felt horrible at much under 15mm sag, it was on a relatively soft spring so I expected to wind it down to 10mm, but even at 15mm it felt hard and very high at the rear, I ran a thundercat at 10mm on the road (Ohlins again) and also added some ride height.

Be interested to know what is considered the "correct" static and rider sag for these bikes as a starting point, but I never get too hung up on being "in spec" as what is most important is how it feels to me, the person riding it!

So far I have just added pre-load until it turned nicely without feeling too harsh and put on just enough rebound to stop it wallowing or feeling vague.

A few extra turns pre-load and some more damping and it feels OK two up although the damping adjuster is almost fully in for two-up use.

Would love some Ohlins, or possibly Wilburs if my budget cannot stretch to the Ohlins prices.
 


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