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guzzler

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G'day folk's.

I've gradually gotten my 01 greenie's suspension sorted over the last year or so and am pretty happy with it!

However, a few months ago the planets aligned and me and a couple of mates got away for a long weekend and instead of my round town backpack ( about 5 kg's worth ) I dug out the tankbag and after new tyres we headed off.Bloody hell the weight of the tankbag ( 10kg's ish?) really helped to further plant the front tyre and it was great and I loved the way she felt! 

A bit of background at this stage, about 10 years ago I replaced the standard Sachs with a Hyperpro 460 shock which came set up for me at 77-80 kilos weight with 10mm preload and it's never been adjusted although I now weigh 87/88 kilos!My riding gear would push it to 95 ish....although it's the same riding gear but don't know/can't remember if that was factored in way back then?

I've raised the forks 8mm through the triples some time ago to weight the front a bit more and this has been pretty good but it dawned on me that maybe I should address the extra weight over the back...

I know I should probably change the spring for a stiffer one but thought in the meantime by adding another 4mm of preload to the shock it would stiffen up the rear a bit more to compensate for the weight and possibly add a wee bit more weight to the front end and also get back a little of the trail I sacrificed by raising the forks.

Any thoughts appreciated...

Cheers Guzzler

Ps I don't want her to steer any quicker than she does or bugger up the handling as it is but really just hoping to get that weighed front feel again....      

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I found that eating a lot more pizza and drinking copious quantities of beer enlarged my stomach to the point it helped with a more forward weight bias on my Greenie!

Just a suggestion..

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11 hours ago, guzzler said:

... I should probably change the spring for a stiffer one but thought in the meantime by adding another 4mm of preload to the shock it would stiffen up the rear a bit more...

Don't confuse spring stiffness with pre-load. They are two different things.

Raising the ride height at the rear, by whatever means, will quicken the steering, and bias the weight balance to the front a bit.

Stiffening the spring will perhaps raise the ride height a bit, but that is not what stiffer springs are about. A stiffer spring will manage a heavier rider weight better. That is the point. If the stiffer spring results in higher ride height, then it is too stiff, or there is too much preload.

Adding pre-load to the setup doesn't stiffen up the spring. It only raises the ride height. If you need a lot of pre-load to get to the optimum ride height, you probably need a stiffer spring. If the spring is not stiff enough, and the ride height is being "corrected" by more pre-load, you are losing suspension travel.

If I have this correctly in my head...

Spring too soft and lots of pre-load to correct the ride height will tend to bottom out.

Spring too hard will tend to top out.

 

It's not that complicated actually, but one needs, perhaps, to sit down with a bottle of Shiraz and think it through several times to get one's head around it. :)

 

Edited by audiomick
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14 hours ago, DucatiGuzziIndian said:

I found that eating a lot more pizza and drinking copious quantities of beer enlarged my stomach to the point it helped with a more forward weight bias on my Greenie!

Just a suggestion..

Ha ha, mate it was pies and red wine that contributed to the weight gain of 10 kilos and got me here!

Well, that and stopping smoking.

Cheers 

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11 hours ago, audiomick said:

Don't confuse spring stiffness with pre-load. They are two different things.

Raising the ride height at the rear, by whatever means, will quicken the steering, and bias the weight balance to the front a bit.

Stiffening the spring will perhaps raise the ride height a bit, but that is not what stiffer springs are about. A stiffer spring will manage a heavier rider weight better. That is the point. If the stiffer spring results in higher ride height, then it is too stiff, or there is too much preload.

Adding pre-load to the setup doesn't stiffen up the spring. It only raises the ride height. If you need a lot of pre-load to get to the optimum ride height, you probably need a stiffer spring. If the spring is not stiff enough, and the ride height is being "corrected" by more pre-load, you are losing suspension travel.

If I have this correctly in my head...

Spring too soft and lots of pre-load to correct the ride height will tend to bottom out.

Spring too hard will tend to top out.

 

It's not that complicated actually, but one needs, perhaps, to sit down with a bottle of Shiraz and think it through several times to get one's head around it. :)

 

A great idea Mick....

I'll have a glass or two tomorrow after work and try and get my head round it,maybe even a pie or two to add more ballast!

Cheers 

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Some good info on here. Especially about the difference between spring rate and preload. But I don't think spring preload has the same sort of effect on a motorcycle as it does on a car in relation to weight. On a car, if I add spring preload on one wheel of a four wheeled car that puts more weight on that tire at that corner of the car. That is in part because of the way cars distribute the total cars weight between all four corners. Of the four wheels / tires if I add preload to one to cause it to support more of the total weight of the car that one wheel / tire will have more weight on it while the weight on the other three also changes. The wheel / tire in the opposite corner will also get more weight on it while the other two will loose weight. Motorcycles do not share their weight the same way between the two wheels. With only two wheels, they can't act like the car with its four wheels. Adding spring preload to the back doesn't put more weight on the rear wheel, and it really doesn't put more weight on the front wheel. Anything that changes the attitude of the bike, how much it is canted forwards or backwards, will have a minor impact on how the weight is split front to back. But it would be a very small effect. The same as dropping the front end by sliding the triple clamps down the fork tubes. That does speed up the steering by increasing the rake, and it does reduce trail. But it is not really putting anything more than a minor amount of increased weight on the front wheel. I seem to recall docc did a test of that once with a pair of scales.

That said, moving weight around on a motorcycle can indeed make a big difference. There are two ways to move weight to the front, clearly one option is to add weight to the front. But adding weight is not always best performance wise. Another option would be to either remove weight from the back, which has a similar effect to adding weight to the front, or even moving weight from the back to the front.  Probably the largest amount of weight on the V11 Sport you can move from the back to the front would be the battery. Anything from just a lighter battery in the same location, to better yet moving the lighter battery forwards on the bike, would help. Probably the largest amount of weight you can remove from the back would be the exhaust. The wheels themselves would be another place you can dramatically reduce weight in large chunks. And while reducing the weight of the wheels does not reduce sprung weight, it does reduce unsprung weight AND rotating weight, both of which are good things in their own right.

There is a reason why our aluminum framed Ducati racebike has a titanium rear subframe that weighs next to nothing. With the L layout of the Ducati V twin it has issues with weight distribution, making it hard to get enough weight on the front. Reducing the weight on the back of the bike also shifts the weight balance of the bike forward same as adding weight to the front. But it doesn't have the weight penalty that adding weight to the front would have. The Guzzi V11 Sport does tend to have a rearward weight balance, and in my opinion anything you do to move the weight balance forward on it would be a good thing.

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On 7/24/2024 at 5:07 AM, guzzler said:

G'day folk's.

I've gradually gotten my 01 greenie's suspension sorted over the last year or so and am pretty happy with it!

However, a few months ago the planets aligned and me and a couple of mates got away for a long weekend and instead of my round town backpack ( about 5 kg's worth ) I dug out the tankbag and after new tyres we headed off.Bloody hell the weight of the tankbag ( 10kg's ish?) really helped to further plant the front tyre and it was great and I loved the way she felt! 

A bit of background at this stage, about 10 years ago I replaced the standard Sachs with a Hyperpro 460 shock which came set up for me at 77-80 kilos weight with 10mm preload and it's never been adjusted although I now weigh 87/88 kilos!My riding gear would push it to 95 ish....although it's the same riding gear but don't know/can't remember if that was factored in way back then?

I've raised the forks 8mm through the triples some time ago to weight the front a bit more and this has been pretty good but it dawned on me that maybe I should address the extra weight over the back...

I know I should probably change the spring for a stiffer one but thought in the meantime by adding another 4mm of preload to the shock it would stiffen up the rear a bit more to compensate for the weight and possibly add a wee bit more weight to the front end and also get back a little of the trail I sacrificed by raising the forks.

Any thoughts appreciated...

Cheers Guzzler

Ps I don't want her to steer any quicker than she does or bugger up the handling as it is but really just hoping to get that weighed front feel again....      

I've noticed that front is too stiff which causes less compliance and deflection at speed and worse buffeting around trucks.

I've learned that stiffening the rear doesn't help.  Soften the front fork and keep around 32 lb in front tire and 38 rear.

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5 hours ago, LowRyter said:

I've noticed that front is too stiff which causes less compliance and deflection at speed and worse buffeting around trucks.

I've learned that stiffening the rear doesn't help.  Soften the front fork and keep around 32 lb in front tire and 38 rear.

Thanks mate.

I haven't had any deflection issues since I did Guzzimoto's Compression leg fix and run Comp at 4clicks from full soft with tyre at 35 psi.

Cheers 

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8 hours ago, GuzziMoto said:

Some good info on here. Especially about the difference between spring rate and preload. But I don't think spring preload has the same sort of effect on a motorcycle as it does on a car in relation to weight. On a car, if I add spring preload on one wheel of a four wheeled car that puts more weight on that tire at that corner of the car. That is in part because of the way cars distribute the total cars weight between all four corners. Of the four wheels / tires if I add preload to one to cause it to support more of the total weight of the car that one wheel / tire will have more weight on it while the weight on the other three also changes. The wheel / tire in the opposite corner will also get more weight on it while the other two will loose weight. Motorcycles do not share their weight the same way between the two wheels. With only two wheels, they can't act like the car with its four wheels. Adding spring preload to the back doesn't put more weight on the rear wheel, and it really doesn't put more weight on the front wheel. Anything that changes the attitude of the bike, how much it is canted forwards or backwards, will have a minor impact on how the weight is split front to back. But it would be a very small effect. The same as dropping the front end by sliding the triple clamps down the fork tubes. That does speed up the steering by increasing the rake, and it does reduce trail. But it is not really putting anything more than a minor amount of increased weight on the front wheel. I seem to recall docc did a test of that once with a pair of scales.

That said, moving weight around on a motorcycle can indeed make a big difference. There are two ways to move weight to the front, clearly one option is to add weight to the front. But adding weight is not always best performance wise. Another option would be to either remove weight from the back, which has a similar effect to adding weight to the front, or even moving weight from the back to the front.  Probably the largest amount of weight on the V11 Sport you can move from the back to the front would be the battery. Anything from just a lighter battery in the same location, to better yet moving the lighter battery forwards on the bike, would help. Probably the largest amount of weight you can remove from the back would be the exhaust. The wheels themselves would be another place you can dramatically reduce weight in large chunks. And while reducing the weight of the wheels does not reduce sprung weight, it does reduce unsprung weight AND rotating weight, both of which are good things in their own right.

There is a reason why our aluminum framed Ducati racebike has a titanium rear subframe that weighs next to nothing. With the L layout of the Ducati V twin it has issues with weight distribution, making it hard to get enough weight on the front. Reducing the weight on the back of the bike also shifts the weight balance of the bike forward same as adding weight to the front. But it doesn't have the weight penalty that adding weight to the front would have. The Guzzi V11 Sport does tend to have a rearward weight balance, and in my opinion anything you do to move the weight balance forward on it would be a good thing.

Thanks mate.

Always appreciate your input on this issue!

As mentioned earlier, I''m a bit heavier these days by the tune of 10 or so kilo's and my main intention here is to lessen the rearward bias of this increased weight by increasing preload slightly. Don't get me wrong the bike still handles bloody well and is stable but I really did like that added weight/feel on the front.I already have the forks up thru triples by 8mm and didn't really want to increase that as it does lessen trail so thought by stopping the bike sagging ( slightly ) under my new lardy physique it might keep the weight forward slightly? 

I guess the best solution would be to change out the spring (it's a progressive one too by the way) next time shock is serviced but this will be a ways away.

Cheers Guzzler

Ps the backpack does contribute to this as well and I might try without it.

Pps All this is really FINE tuning the handling but if it makes it even better then it's been worthwhile eh.

 

 

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I'm reminded of  something I read in a bicycle magazine once regarding saving weight on a racing bike: the cheapest place to save weight is on the rider.

 

Maybe the concept lets itself be applied to handling on a motorcycle as well. :huh2: :whistle:

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Mate

It gets harder to lose weight the older you get....

I'm also kinda fond o my pies and wine.....!

Ha ha Cheers Guzzler

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9 minutes ago, guzzler said:

Mate

It gets harder to lose weight the older you get....

You don't say... :whistle:

I've actually lost about 8 Kilos over the last couple of years. That has to do with working in a building where one walks a lot to get from here to there, and not eating as much, after a year or so of practically no work due to CoVid during which I put on a bit.

Smoking is probably also a factor, but I can't recommend that as a tactic for losing weight. It's a really bad idea. :wacko:

Edited by audiomick
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Yeah mate

Exercise is the key isn't it.

I don't work anywhere near as physically as I did when younger plus add in a wife who loves to cook (and damn good at it too!) then Covid and working from home et voila...

No way I'd ever smoke again so that's outa the question!

Then again it being winter here, I'm back to my lumberjack impersonations so maybe sawing the wood instead of the chainsaw? Nah that ain't gunna happen!

Weight's holding steady so will keep an eye on it before any drastic measures are called for.....

Cheers 

 

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I just heard back from Hyperpro Australia.

They can lengthen the shock by 5mm for me for $300 plus postage to/from Sth Australia.

Turnaround is 3 x days.. 

I wonder if this might be the best solution to put some more weight on the front as the shock still feels good as supplied with 10mm preload.

To the others who have the Ohlins shock which is 5mm longer than standard....how do you find this? Did it weight the front any more?

If I did this, would you do anything with the forks ie put them back flush or leave as is at 8mm up thru triples??

Cheers Guzzler

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