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Remember I had the forks modified and had the impression they had been set up for the bike ( very naive I know :eek:). Previous bikes compression adjustments rarely seemed to do very much. I had forks modified on the Speed Triple, according to Maxton the compression damping did nothing at all. I also find myself near the front on ride outs, even with the forks riding so high, like you, I managed to ride around it, but on really twisty C roads, following Sports 600s after an hour of riding it felt like I had been in the Gym all day. My forearms were pumped and wrists were aching.

Yes, flywheel and crank effects I'm aware of, but I don't need a race bike, just something that turns in and rides well on the stuff that masquerades as roads up here. Very different in Australia. We often ride on very narrow, twisty roads which are very broken and rutted. There can be 20 sharp bends in the space of a few hundred yards.

It's funny that you made mention of that technique of braking. I use that on really tight alpine hairpins. You shouldn't need the rear brake. I load the front up against the engine to smooth the slow speed turning. I was shown that technique by a really knowledgable rider and it's not found in any books. I think it's more applicable to smoothing the power pulses from a big twin than a multi. I though he was having a laugh telling me to apply front brake mid corner.......but he made sure I understood 'with the throttle on or you will crash':)

You mis read what I had written. I don't feel the need to do anything with the rear of the bike now I have the forks sorted. It doesn't run wide under power and therefore I'm saying that there is no need to raise the ride height. The problem that is being solved by increasing the ride height isn't the right one. If you go into a bend on a trailing or neutral throttle then the bike will squat as cornering causes the bike to decelerate ( partially due to the tyre diameter decreasing and lowering the gearing ). Raising the back will help to balance that effect and gives the impression that it's making the bike easier to turn in. Also, as you said, in a series of rapid bend transitions it's more natural to be off the throttle, so it certainly feels like it turns easier.

But actually, I suspect ( I don't know for certain) that what is happening is that it's being used to counteract lazy throttle control and not really affecting proper turn in under throttle on. The compression damping was making my forks ride too high at turn in so it was an effort. Normally as we approach for turn in we are on a lagging throttle and the weight goes forward compressing the forks and aiding the turn in. If the forks ride too high and are too stiff they just don't move and so turn in becomes a struggle. Once the turn point of throttle 'on' is reached then it wasn't a problem, the forks were where they should be and the back end didn't squat.

If that makes sense?

Now, going back to the forks in their original state, this wasn't the issue, it was the awful rebound damping that was a problem, either packing down or springing up like a Kangaroo, very harsh damping. It was impossible to find a good setting, hence why I had the forks modified.

The rider who showed me the technique of mid corner braking ( that was on my Monster not the 4s, had ridden the 4s before buying a K1200s and thought the forks were dangerous if you ride really quickly ( and he did ride very quickly despite his age, years of racing and road riding since he was 6 years old). I wasn't really that bothered because I dont ride that quickly, but found that the forks didn't work for me.

I should say, that a good rider can get around virtually anything, I don't class myself as one so I need help.

So, I don't need to raise the back end because the bike turns in perfectly and the only modification is fork springing and damping. Even with the original forks I was relatively happy with the turn in, just not the forks performance on and off the brakes and during the turn.
 

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"Easily as big a factor if not more than putting the light Marchesini wheels as Ducati did with this model."

Interestingly enough I understand the Marchesini's are not lighter as such but as they are 5 spoke there is less weight at the rim so they offer less gyroscopic effect.
 

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"But actually, I suspect ( I don't know for certain) that what is happening is that it's being used to counteract lazy throttle control and not really affecting proper turn in under throttle on."

Been riding for 35 years (26 bikes) , passed two Advanced Tests + an Observers Test , acted as an Observer for the IAM and Bikesafe and can assure you that , personally , I know how to enter a corner and the affect of throttle application (Good & Bad) so my ride-height adjustment was not due to any "Lazy throttle control".

I do , however , think a little knowledge can be a bad thing......................
 

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"But actually, I suspect ( I don't know for certain) that what is happening is that it's being used to counteract lazy throttle control and not really affecting proper turn in under throttle on."

Been riding for 35 years (26 bikes) , passed two Advanced Tests + an Observers Test , acted as an Observer for the IAM and Bikesafe and can assure you that , personally , I know how to enter a corner and the affect of throttle application (Good & Bad) so my ride-height adjustment was not due to any "Lazy throttle control".

I do , however , think a little knowledge can be a bad thing......................
That sounds vaguely like an insult. Suspension, steering and frame geometry are not exactly simple. Even the experts who design them get them very wrong at times. I'm suggesting something which you suddenly think is a pop at your riding ability, it's not, I just wondered why raising the ride height would have that effect when it's disputed in the article posted. I note on your signature that you have had the front forks re-worked with Racetech valves. So by inference you didn't do that because you were happy with the forks either.

What isn't clear is that with the forks set correctly the bike turns in beautifully without raising the rear. On a Yamaha Fazer I raised the ride height by maxing the preload, but that's not quite the same as pure ride height adjustment. The result was a tightening up of the turn in to bend. In comparison the ST turns in a lot better.

Why didn't Ducati raise the rear if it improved it ? There is no mention of it in the owners manual. What it does do is push weight forward onto the forks, it's possible that it might be that action which is affecting turn in, but if the forks have the right springing, sag and damping settings it shouldnt need the extra weight over the front.

I'm not saying it doesn't make a difference, but I'm curious as to what exactly the effect is because it's not exactly clear ?
 

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I'm sure if we knew the truth, we would find a lawyer somewhere telling Ducati - Offer the ride height, but DO NOT go into any detail....
It's up to the owner to keep it stock or take our own chances.
 

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Raising the rear gives the same result as lowering the front, it decrease's the rake/trail and quickens the bikes turning.
If you use the shock preload to change the geometry of the bike you've changed the sag of the bike. To me that's what's great about the ride height adjuster, loosen two bolts, turn the bar and you've changed the rake/trail of the bike. Want more, repeat. A lot easier than having to pull the shock and change shims under the shock.
 

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Not what is says here:

Do not adjust for corner entry or mid turn using the rear ride height. Many uneducated riders will say that raising the rear does the same as dropping the front, but this is flat out wrong. No matter how much you move the forks in the clamps you will not effect the squat characteristics of the rear end (essentially).


Bit more research and I think I finally get it. That ( essentially ) is the clue.

If you raise or lower the forks ( or in my case set the compression damping correctly...doh ) then you affect turn in. If you jack the rear end then you affect turn in and squat. So the advice on the given is to treat them separately. If you get too much anti squat then the back end is effectively rigid under acceleration and then will turn around the wheel lifting the front end.

So it's better to drop the forks through the yokes once you have the sag settings correct to quicken steering, then, if the bike shows a tendency to run wide during acceleration out of a turn add some ride height.

It's fascinating how much contradicting information there is. I think the thing is that a bike goes through so much dynamic change in a turn, that effectively its a huge compromise because the bike does not maintain a level attitude as braking, turning and accelerating forces are applied. So stability becomes slow turning, good turn in results in instability somewhere else. Very tricky.
 

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I am just pleased that a Geordie is sorting this out :) !!!

The theories all make sense to me, that is they are reasonable in argument etc. Translating that into specific measurements and settings oil weights etc is the art and I hazard why race teams with the budget spend the cash trying to get perfection, at least on a specific track, under specific atmospheric conditions (including temp) for all the other myriad factors that go into the equation...

I admit to fiddling with my settings only rarely, having set my sag and having the Ohlins serviced by an Ohlins tech and the Showa forks by my favorite Ducati mechanic, beyond that I have eased off most of the rebound damping and have light compression damping setting in my ST4s.

Been too long since visiting Geordie Land and I do wish I could get back to see some of "mates" at Rubb UK and Airowsafe. Have a John Smiths for us and keep up the great suspension discussions!!!
 

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....unlike most tyres, which weigh a ton compared to something like a Michelin Power Pure 2CT.
Thats one of the reasons I might switch back to Michelins of some sort alongwith not needing to cahnge pressures all the time.
But first I need to get these Roadsmarts worn-out !
 

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Not what is says here:

Do not adjust for corner entry or mid turn using the rear ride height. Many uneducated riders will say that raising the rear does the same as dropping the front, but this is flat out wrong. No matter how much you move the forks in the clamps you will not effect the squat characteristics of the rear end (essentially).


Bit more research and I think I finally get it. That ( essentially ) is the clue.

If you raise or lower the forks ( or in my case set the compression damping correctly...doh ) then you affect turn in. If you jack the rear end then you affect turn in and squat. So the advice on the given is to treat them separately. If you get too much anti squat then the back end is effectively rigid under acceleration and then will turn around the wheel lifting the front end.

So it's better to drop the forks through the yokes once you have the sag settings correct to quicken steering, then, if the bike shows a tendency to run wide during acceleration out of a turn add some ride height.

It's fascinating how much contradicting information there is. I think the thing is that a bike goes through so much dynamic change in a turn, that effectively its a huge compromise because the bike does not maintain a level attitude as braking, turning and accelerating forces are applied. So stability becomes slow turning, good turn in results in instability somewhere else. Very tricky.
And which is easier ?

Dropping the forks in the yokes with all the necessary work to achieve same ? (after checking there is enough clearance with fully compressed forks , of course) or raising the rear end with the helpfully supplied and fitted ride height adjuster ?

Stabilty wise , never had an issue in any format , even with the rear raised.
Of course none of us know how your bike was set when you bought it or even now , so difficult to know how you like your bike to respond.

Regarding the Racetech modifications to my own forks , this was merely to attain a better ride quality over small bumps which I found to be poor with the standard valving. I never had a problem with outright performance at speed into/through and out of corners once I had found the right settings (for me).

As to the inferred insult , just an observation my dear chap , take it as you wish but I think that casting vailed aspertions on peoples riding (particularly on a , generally , well informed and experienced forum of riders such as this could be taken equally as insulting.

Anyway glad that you feel you now have an understanding of the dynamics of motorcycle suspension geometry.
 

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Without meaning to cause any kind of problem I would like to assemble "Lazy throttle control" and

casting veiled aspersions on people's riding (particularly on a, generally, well informed and experienced forum of riders such as this).
I must admit I too had the "Gearbox reaction" when I first read the term. On further thought I suspect that was wrong. So Thirdway can you please tell us what you mean by "Lazy throttle control" as I truly cannot think of what it could be? Are we just talking about not changing down a gear and lugging a motor (Power Commander 3 dyno'd on "fixes" that)? Or something else?

My pet "laziness" hate is people that are too lazy to stay on their side of the road - despite that there is visibility to see the road is clear so it is safe I know how critical bike position on the road is, and any small errors between plan and reality (that are not situation driven) are a great big red flag that fatigue is creeping up on you, in fact its here! Despite that the error may be small and easily overlooked its what it means that matters most. So I see people give away one of the most useful monitoring tools when they accept this short-cutting as OK. It becomes particularly relevant on blind corners when the pattern has started.....
 

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It's not about which is easier, it's about which is correct.

If you raise the ride height you affect both anti squat and turn in.

Infact it's very easy to drop the forks a couple of mm and it makes a big difference. Raising ride height means freeing off the seized adjuster, adjusting the chain for a none standard setting and often having a problem with the side stand height. For me it would also mean dangling legs:)

It's easy to imagine that a raised rear would prevent the bike squatting as much on the entrance and through a turn on a neutral throttle.

The bike is also sensitive to tyre profile, so maybe it compensates a bit for wear. I just chucked my tyres away after the profile wore down even though they were a long way from illegal.

I certainly wasn't casting aspertions, I was trying to understand why it was necessary to alter the anti squat as well as the geometry. Lazy throttle action could well have explained it. Don't say that everyone understands positive throttle through a bend, because if that was the case we wouldn't have so many accidents as people wind off the throttle and fixate.

You are obviously well aquatinted with positive throttle through a turn so that cannot be the case for you, so no need to throw your dummy out. It was a discussion. My word you advanced riders are touchy, chill out.
 

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Without meaning to cause any kind of problem I would like to assemble "Lazy throttle control" and



I must admit I too had the "Gearbox reaction" when I first read the term. On further thought I suspect that was wrong. So Thirdway can you please tell us what you mean by "Lazy throttle control" as I truly cannot think of what it could be? Are we just talking about not changing down a gear and lugging a motor (Power Commander 3 dyno'd on "fixes" that)? Or something else?

My pet "laziness" hate is people that are too lazy to stay on their side of the road - despite that there is visibility to see the road is clear so it is safe I know how critical bike position on the road is, and any small errors between plan and reality (that are not situation driven) are a great big red flag that fatigue is creeping up on you, in fact its here! Despite that the error may be small and easily overlooked its what it means that matters most. So I see people give away one of the most useful monitoring tools when they accept this short-cutting as OK. It becomes particularly relevant on blind corners when the pattern has started.....
Yes, lazy throttle is not using positive throttle throughout the term ( there are some places that's not possible such as riding down steep hills and adverse cambers ). What isn't often appreciated is a bike is a right clever bit of kit. When you lean over, the shape of the tyre means you are actually lowering the gearing. As you know, if you change down with a closed throttle the bike slows. So, if you enter a turn on a neutral throttle, in effect you are slowing.

The bike is designed to have positive throttle applied throughout the turn, if you don't it gets loose. Depending on the turn and the bike set up, it can feel like its turning too tight as the braking action loads the front end and quickens the steering or it can run wide.

Running wide on the exit is too much power too early, or a badly set up bike. The more likely culprit is throttle control. Riders often coast ( lazy throttle) around most of the bend and at some point realise they could have gone faster. It often means they mentally try and recover the speed by bullying the throttle before they get a clear view of the road ahead. The bike then goes wide early on, or they suddenly realise that the road quickly bends the other way and they get caught out. That's why they often end up on your side of the road.

Anyway, nothing to do with PC3s but gearing obviously is critical to acceleration.
 

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It's not about which is easier, it's about which is correct.

If you raise the ride height you affect both anti squat and turn in.

Infact it's very easy to drop the forks a couple of mm and it makes a big difference. Raising ride height means freeing off the seized adjuster, adjusting the chain for a none standard setting and often having a problem with the side stand height. For me it would also mean dangling legs:)

It's easy to imagine that a raised rear would prevent the bike squatting as much on the entrance and through a turn on a neutral throttle.

The bike is also sensitive to tyre profile, so maybe it compensates a bit for wear. I just chucked my tyres away after the profile wore down even though they were a long way from illegal.

I certainly wasn't casting aspertions, I was trying to understand why it was necessary to alter the anti squat as well as the geometry. Lazy throttle action could well have explained it. Don't say that everyone understands positive throttle through a bend, because if that was the case we wouldn't have so many accidents as people wind off the throttle and fixate.

You are obviously well aquatinted with positive throttle through a turn so that cannot be the case for you, so no need to throw your dummy out. It was a discussion. My word you advanced riders are touchy, chill out.
So to adjust the ride-height using the rod , you take two spanners , put the bike on its own stand , loosen the wto nuts and adjust as preferrred then retighten. Job Done

Dropping the forks (doing the job properly to avoid any stiction caused by misalligned forks).

Prework - Arrange some method to suspend from of bike.

1 - Remove mudguard
2 - Remove brake calipers
3 - Remove wheel
4 - Loosen bolts on each leg and reset each ensuring that the spindle still passes freely through the bottom of the legs. Adjust if necessary.
5 - Refit all the above.
6 - Bounce the supension before tiughtening and torque all the spindle clamps to ensure correct allignment of the forks.

I will have missed a bunch of anal stuff about having the correct torque wrenchs/figures and Lock-Tight etc , etc but you get the picture

Still think its the same ?

Entering a corner (point of turn-in) you would might still be on the brakes or , ideally , on a neutral throttle ready to re-apply once you had seen and picked your exit line out of the corner so why would the bike squat ?
It is only at the point of opening the throttle that the rear end would start to sit down (squat) and the amount would depend on the suspension (springs/damping) and to a lesser extent the geometry.

I think you need to 'study' some more before attempting to give guidance to others who may be vulnerable to poor , overly simplistic , advice.
 

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...But first I need to get these Roadsmarts worn-out !
I wouldn't get too carried away about the Roadsmarts. I had a set on and the rear was gone in barely 3,500 miles but I got over 5K with Pirelli Angels. The Roadsmarts were the most expensive and shortest lasting tyres I have ever fitted. I had expected better for a new generation dual compound tyre. These were the first Dunlops I had tried for over 30 years and will almost certainly be the last.
 

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Oh your that sort of advanced rider. Enough said. One reason why I never bothered was because I realised I actually didn't know it all and kept an open mind.

You didn't mention changing the chain tension as part of the ride height adjustment ? Well, if you don't your going to find the chain is no longer at the correct tension otherwise you end up with a tight chain which restricts suspension and destroys the gearbox. Worst might be a snapped chain wrapped around the back wheel and a cartwheeling bike and rider. Still, you obviously know best.

This is pretty good article on squat and the effect of differing sprocket sizes. I happen to know this stuff through having a variable geometry mountain bike. You probably won't be interested as you are obviously above any form of learning because of your status as an advanced rider.

Motorcycle Art and Science - Traction & Geometry - Sport Rider
 

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Entering a corner (point of turn-in) you would might still be on the brakes or , ideally , on a neutral throttle ready to re-apply once you had seen and picked your exit line out of the corner so why would the bike squat ?
It is only at the point of opening the throttle that the rear end would start to sit down (squat) and the amount would depend on the suspension (springs/damping) and to a lesser extent the geometry.

I think you need to 'study' some more before attempting to give guidance to others who may be vulnerable to poor , overly simplistic , advice.
Takes me 20 minutes to Drop the front and torque it back up. Riders should learn to do it anyway even to correct skewed forks.

Anyway I digress. Neutral throttle or brakes up to turn in, correct. Then you are proposing a neutral throttle around the turn. Most people will take that as a static throttle through the turn. I'm afriad you would be slowing down and if what you say is that you understand how to use the throttle during a turn you will know that you always keep a degree of positive throttle throughout the turn ( which is done on initial entry and not half way round a turn). When you can add more acceleration at which point anti squat makes an appearance on the exit when you give the bike more drive.

Read the article: don't adjust ride height for turn in or mid corner, only for increasing throttle on exit. It's not me saying this, it's suspension specialists from road racing. But I see a point when both turn in and anti squat were not working the way you want even with proper throttle use. Then it would make sense to alter the ride height. You might even want to play with it if you have changed sprockets.
 
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