Heads up!

[Guest ratchethack]

Well, as long as we seem to be relating "tank slapper experiences", let me suggest as many variable factors I can think of, that in some combination with each other, can contribute to front-end oscillation.

 

In no particular order:

 

Air pressure, width, and aspect ratio of tires F & R, model of tires F & R, condition of tires F & R, match of tires (model, aspect ratio, width, condition, and pressure) between F & R, weight and riding position of rider, weight and placement of gear, match of fork spring rate to weight of rider and load, match of shock spring rate to weight of rider and load, condition of springs F & R (sacked-out or not, or somewhere between), F & R preload settings, condition of fork cartridges, condition of shock, match (F & R) of all fork and shock settings, setting of steering damper, condition of steering damper, F & R compression settings, F & R rebound settings, condition and/or adjustment of bearings (wheels, steering head, and swingarm), height setting of fork tubes in triples, amount and viscosity of fork oil, integrity (straightness and soundness) of frame, alignment of fork, alignment of swingarm, aerodynamics of luggage, aerodynamics of fairing, (I've undoubtedly missed at least a half-dozen more).

 

The point I'm attempting to make is, (again): If your bike is far enough out of whack in one of, or more than one of the above parameters in some combination to cause them to "conspire" in a particular way, a front-end oscillation is more than possible on (nearly) any bike - and I humbly suggest that this can happen virtually regardless of any OEM rake and trail (let's not even think about "long bikes" please?) And thank you.

 

So if somebody says they had a tank slapper and doesn't mention anything about how their bike is set up or even if they do, I submit that this doesn't necessarily implicate the design of the motorcycle unless or until stuff like all of the above is fully taken into consideration and/or explored.

 

We had one prev. mentioned person a few years back recount an "event" where he suddenly lost control on a straight section of road. I think it's important to note that he didn't mention a thing about fork oscillation before the crash, nor did he mention even one of the above parameters. His post indicated only that he suddenly found himself doing the 50 meter macadam backstroke.

 

Yet in the ensuing forum discussion, this experience was characterized by others as "a problem". The implication was that there was an "inherent problem" with the rake and/or trail of the frame of that particular model Guzzi, which happened to be a short-frame 2000 Sport (same as mine). The guy wound up selling his Guzzi. By the time he did this, I'm sure he had become convinced there was an "inherent tank-slapper problem" due to the design of the short-frame bikes.

 

I've seen lots of incredibly dumb things done to motorcycles, in some cases stupid enough to be life-threatening. Let's face it - there are many riders who don't understand the first thing about how to set up their bikes, let alone how to keep it all in a safe balance... How hard is it to imagine that someone who doesn't even know enough to know that there are important things he doesn't know (got that?) might in fact have caused his own problem? (OPERATOR ERROR!) A rider without a basic understanding of motorcycle setup fundamentals is a danger not only to himself, but to everyone on the road.

 

I call foul!

 

By all means - Fire at will, Gents.

[Guzzirider]

I remember this being a discussion topic in 2000 on the MGCL forum where some owners were complaining of slappers. The solution in terms of setting up the bike was discussed and this seemed to solve things for those owners of new V11s who were complaining- don't ask me what the recommended settings were- I can hardly remember what happened yesterday let alone five years ago.

 

I rode the UK press bike for 2 weeks in 2000 shortly after it was launched- and it did wobble a bit over the ton but nothing to write home about compared to the old big twin shock Jap fours I used to ride as a teenager. Unfortunately it had been used by Fast Bikes magazine beforehand and was pictured pulling massive wheelies- the gearbox broke while it was in my possession so the importers gave me another one which also wobbled a bit.

 

To me the fact that nobody has mentioned this as a problem on OUR forum recently means it ain't a real issue.

 

Guy

[jbuzbee]

Ratchethack,

 

When I rode a Ducati Monster I frequented the Ducati Monster List: Guys would drop the fork tubes in the triples to fit clip-ons, raise the rear ride hieght and then complain about front end instability!

 

Is this an Italian thing or are other bikes this susceptible to changes in geometry?

 

jb

[Guest ratchethack]

jb, I'd venture to guess the Doofuses who did this did it because they thought it "looked cool". Most of the newer high-zoot sport bikes I've looked at seem to provide lots of setup adjustability. Best know what the hell one's doing or be prepared to pay the piper.

 

IMHO, the behavior of fools knows no bounds, neither marque to marque, nor rider to rider.

[pete roper]

I've seen lots of incredibly dumb things done to motorcycles, in some cases stupid enough to be life-threatening.  Let's face it - there are many riders who don't understand the first thing about how to set up their bikes,

 

62198[/snapback]

 

This is, unfortunately, very true. It's more than a little bit the fault of the magazines which will print some 'technical' article written by a journalist who ISN'T a mechanic or an engineer but who knows just enough to be dangerous. This is lapped up by the great unwashed who then consider themselves to be *expert*. I come across it the whole time and freely tell people that I'm no great expert when it comes to bike set-up and tend to push 'em in the direction of Frank Pons if they want it to work the best it can. Usually though just explaining to 'em that a motorbike is really a glorified shopping trolley that has been cut in half and is being pushed backwards is sufficient to ensure they think I'm barmy and gets 'em out of my hair. The vast majority of these nongs can quote rake and trail figures at you till they're blue in the tits but haven't a clue what they mean or how a single track vehicle steers.

 

Pete

[Guzzirider]

This is, unfortunately, very true. It's more than a little bit the fault of the magazines which will print some 'technical' article written by a journalist who ISN'T a mechanic or an engineer but who knows just enough to be dangerous.  The vast majority of these nongs can quote rake and trail figures at you till they're blue in the tits but haven't a clue what they mean or how a single track vehicle steers.

 

Pete

62321[/snapback]

 

Its worse than that- the bike journos don't even get their basic facts right when it comes to talking Guzzis- I remember quotes like "chain drive conversions are common" and other such BS.

 

All the prices, comments and specs are wrong in mags like Bike magazine and there has been a real anti-Guzzi bias until Piaggio took over and started waving their advertising budget.

 

Only Motorcycle Sport And Leisure seems to know what they are talking about and that is because they keep them and ride them for longer distances and are not obsessed about 170rwbhp.

 

Guy

[Baldini]

Think Murray said it right about the spineframes "there's a technique to them - they're quite capable of being shoved into some spots they can't quite get out of".

 

V11's are heavy & carry it too far back. Crude rear suspension design struggles to cope w/ a mass of unsprung wt, s/a should've been made longer when 6 speed permitted, hub lightened. Rear wheel/tyre's far too big. Seat's too far back so's to give a decent size tank. This is fine, steady on smooth roads but hit a series of dips & bumps mid corner when pushing it & things front'll wander & push wide, back'll be moving all over the place. Stiffer springs, less damping, raised forks in yokes, & learned to let it go on, but key is tyres that'll stick. Guzzi's abilities always surprise those on sports bikes whose only knowledge is secondhand. But don't pretend they'd stay with a real sports bike, given equal riders, ridden hard..

 

KB

[Guzzirider]

Ride magazine proudly announce on their front cover this month a test of the Guzzi Griso 1000.

 

Either they have a sleeved down version or they have cocked up on their facts again!

 

Guy

[belfastguzzi]

Ride magazine....a test of the Guzzi Griso 1000.

 

Guy 

62377[/snapback]

...so I rush to Tesco on the way home this evening. Car on roundabout ahead doesn't bother about the fact that I have right of way through the O-about and pulls on...and me with no life insurance...anyway, having risked life and limb, I collect Ride mag to devour the 'test'.

 

It's rather small and limited (I think one of the staff saw one somewhere), so didn't add anything new: they do like the look of the thing though and pretty much advise The Readership to go out and buy one. Hope that doesn't happen.

 

Over the page there's a small piece on fitting a Scottoiler. So I didn't risk my life for nothing then.

[Martin Barrett]

Over the page there's a small piece on fitting a Scottoiler. So I didn't risk my life for nothing then.

62415[/snapback]

 

I used one on my FJ top piece of kit. Made sure my panniers ( Krausers K2 white with red doors) allways were splatted in lube, they never rusted.

 

I could fit it to the Lemans to replace the slow loss of engine oil.

[belfastguzzi]

I used one on my FJ

 

I could fit it to the Lemans to replace the slow loss of engine oil.

62418[/snapback]

 

It goes on the bike? I missed that bit.

 

Yours,

slippin' an' slidin'

[Guzzirider]

...so I rush to Tesco on the way home this evening. Car on roundabout ahead doesn't bother about the fact that I have right of way through the O-about and pulls on...and me with no life insurance...anyway, having risked life and limb, I collect Ride mag to devour the 'test'.

 

It's rather small and limited (I think one of the staff saw one somewhere), so didn't add anything new: they do like the look of the thing though and pretty much advise The Readership to go out and buy one. Hope that doesn't happen.

 

Over the page there's a small piece on fitting a Scottoiler. So I didn't risk my life for nothing then.

62415[/snapback]

 

 

Bike magazine have a better test- by Mick Phillips who used to work for Classic Bike and I think owns a V7 Sport. Reasonably positive- I think that huge Piaggio advertising budget is working its magic plus its probably a good bike anyway.

 

Guy