geometry 101

[docc]

My information (albeit, translated loosely from the Italian) says my 2000 V11port has 1471 mm wheelbase, 25 degree caster and 92 mm trail.

 

The current breed is1490 mm , 25 degree caster and 104 mm trail.

 

How did they change the trail that much without changing the caster angle?

Or are there vagueries in the numbers?

[Paul Minnaert]

They added just some centimeters just behind the stearinghead. So there is the extended wheelbase from, and maybe they changed the fork triple clamp? In the 2001 model it has 40mm extension, don't know if the older was the same?

[docc]

My 2000 sport is offset 40 mm also. I wonder about the 2002 and newer?

[Mike Stewart]

My information (albeit, translated loosely from the Italian) says my 2000 V11port has 1471 mm wheelbase, 25 degree caster and 92 mm trail.

 

The current breed is1490 mm , 25 degree caster and 104 mm trail.

 

How did they change the trail that much without changing the caster angle?

Or are there vagueries in the numbers?

Doc,

 

The specs. for my 2000 V11Sport is 25 degrees of castor, for some reason, I measure 26.5 degrees with the forks showing 10mm. ontop of the triple clamps. I have talked to Guzzi suspension guru's and have been told that the measurement I have taken were right and making the head angle steeper to 25 degrees would correct the nervousness of the bike. Humm. another project comming up!

 

Mike

[docc]

Mike,

 

When you say 10 mm "on top of the triple clamp" I assume you have dropped the clamp on the forks that amount?

 

I would have thought dropping the clamps would STEEPEN the rake. How are you measuring that angle?

 

My forks are on the bench. Wrestling with the dismantle. Changing spacer (hopefully) and oil (5 wt Silkolene). Maybe better springs next tme around.

[Mike Stewart]

Docc,

 

 

The forks are sticking out of the clamps 10mm. to steepen the head angle. I have a angle gauge that that can read 360 degrees of a circle. The fork angle of my Falco and the wife's Monster read right on the money. The 26.5 degrees are with the forks up in the triple clamps. There is a company that makes a steering bearing set that steepens the head angle by one degree and they also offer the triple clamps with a different offset to change the trail. Now if I can only figure out where these guys are.

 

Mike

[callison]

http://www.daes-mototec.de/

Right side, where it says Produkt, click on Fahrwerk,

where it says "DAS-Fahrwerksgeometriekit Fur MOTO GUZZI 1100 Sport, Daytona RS, V10 Centauro mehr...", click on the "mehr".

 

Alta Vista gives the following translation (I've substituted some stuff that doesn't come across, but made no particular effort beyond that).

 

Since it chassis geometry kit A typical characteristic of the MOTO GUZZI 1100 Sport/Daytona/Centauro family is the Untersteuern in curves. The quicker the pace is, the more strongly "pushes" the motorcycle over the front wheel and besides bends the front spar and with the strong accelerates to steering wheel striking. Responsible for this are before all a strongly hecklastige weight distribution, as well as the steering geometry of the series Guzzi`s. With the since it chassis geometry kit a practicable was found here and not to expensive solution: Eccentric bushes with 0.1 mm undersize and new taper roller bearings are fit in and bonded in the frameworks. Thus the again made guidance shank pipe is more steeply fixed around 1 degree and guaranteed at the same time that with bearing seats out of round in the framework the taper roller bearing keeps its roundness. By the new CNC milled fork bridges with alternatively 30 or 35 mm offset the wake is adapted. Besides the wheel base is shortened around nearly 30 mm and thus a clear gewichtsverlagerung is reached forward. Result: The motorcycle drives itself many more handily and all more neutrally, it "pushes" no more over the front wheel. One has thus with extreme driving conditions a very good feeling for the front wheel! Scope of supply: 2 eccentric cam bushes, 2 taper roller bearings, special adhesive, sentence CNC milled fork bridges with pressed in torque tube, drilling fixture to the do-it-yourself installation on loan, as well as a detailed assembly instruction. Operating range:

 

240-0001 chassis geometry kits, 1 degree/30mm offset, for MOTO GUZZI 1100 sport IE, Daytona R-S, V10 Centauro - 938.10 Euro

 

240-0002 chassis geometry kits, 1 degree/30mm offset, for MOTO GUZZI Daytona - 938.10 Euro

[dlaing]

Less rake should result in less trail, so if Mike's is 26.5 degrees it should have more trail than a bike with a 25 degree rake, assuming all other things being equal...

Guzzi specs are often wrong.

I have heard different stories about how this effects handling.

I believe the V1100Sport has more rake, a slightly longer wheel base, and is more stable but less nimble than the V11Sport.

[docc]

Carl,

 

I ver muust enjoyed the roughly translated geometrikit deskribing the changes to V11 handling. I'll have to see if Konrad can help me out (I get "untersteuern" but " gevichsterlagerung??")

 

And the 25 degrees? This is a myth? Like the 91 horsepower, 471 pounds and 5.8 gallon tank? Oh, and the speedometer that reads rather in excess of reality. ( if you average the extreme sweep of the oscillations).

[Mike Stewart]

So if it is 1200. bucks to change the head angle one degree, wouldn't it be cheaper to get the front frame off a wrecked 02 Lemans (25 degree head angle) and install it on the V11? Or am I missing something here.

 

Mike

[Guest Jeff Kelland]

WOW!!! you guys going racing or something? My last bike was a Ducati 748. It had an adjustable steering head angle. I tried it both at 24.5 and 23.5 degrees. I could tell the differance between the two, it steered quicker with the steeper angle. I am a good rider with over 25 years of experience including some racing. At either angle I could ride it to my limit of sane street speeds, I could never exceed it's limit. My 2002 Le Mans handles pretty damn good right out of the box. Light and neutral at most reasonable speeds, a little heavy when pushed but responsive enough to agressive inputs. I don't see that I'm going to exceed it's limits either. No critisism(sp?) intended gentlemen, I just think if it ain't broke why fix it?

[callison]

And the 25 degrees? This is a myth? Like the 91 horsepower, 471 pounds and 5.8 gallon tank? Oh, and the speedometer that reads rather in excess of reality. ( if you average the extreme sweep of the oscillations).

 

Somebody had mentioned the kit for reducing the steering head angle, so I referred to the DAS MotoTec site and offered the Alta Vista translation. The kit is for the Daytona RS's and Sport 1100's though, bikes that are noticeably less quick steering than a V11 Sport. If the V11 Sport needs to have quicker steering, I haven't noticed it. Probably needs a quicker rider first

 

The 91 HP is undoubtedly the result of one very good optimum run on a dyno measured at the crank, not the rear wheel. All sales departments do this. The weight is for a dry bike and probably a pre-production V11 Sport with all of the additional frame gussets and such. Failure to upgrade specs sometimes makes them look better, especially when the bike has gained weight. 5.8 gallons? Never saw that mentioned anywhere, but if it were, it would be an outright lie. And speedometers, everybody's favorite bitch. Well, from what I've read, European specs allow for a speedometer that reads as much as 7% fast but 0% slow with heavy fines for failure to comply, so it isn't surprising that speedometes read really optimistically. It would be better though, if they read optimistically realiably

[dlaing]

I just think if it ain't broke why fix it?

I think those of us with the 2000 models would like to make the bike a littler more stable.

Guzzi "fixed" it in 2001.

There are probably better ways to fix it like not using Pirellis or Metzelers on the front, or a Contiforce on the rear. All good tires, but twitchy.

Maybe a fork brace, or a frame brace as shown on the Japanese Jinguzzi (sp?) website.

Or just properly set up suspension.

Personally I find that the quick steering is fun, but I get nervous and frequently over react.

I just put a Metzeler on today, and it steers just as quickly as the Pirelli did.

I should have listened to Mike Stewart's comments on the Metzeler Sportec M1.

I think a Michelin on the front may be the answer...

Or buy a Rosso Corsa...

[Mike Stewart]

Humm,

 

I will have to check Carl's 2001 TT the next time I see him. I wonder what his head angle is. I talked to Todd (Racerx) at the Prescott rally and he agreed with me about the head angle being too slack on the 2000 V11Sports and causing the twitcheyness of the bike when pushed into a turn. Depending on tire combinations and skill level (nerve of steel), one must start out with a clean pair of shorts! I feel really good on my 00 V11Sport, but know it could be better. The 03 Lemans is really stable through the turns, rock solid. Is it the added 25mm. in wheelbase that makes the difference or the true 25 degree head angle? Inquireing minds want to know.

 

Mike

[Guest Jeff Kelland]

In all fairness, I haven't ridden a v11 sport in a long while, I do know that the Le Mans has a slightly longer wheel base and the rear wheel is wider, which, if I understand correctly, gives the tire the correct profile. My Le Mans is truly stable at all times even with the damper at full soft, the ducati was felt a little nervous and demanded constant attention with the race setting. It was much happier ridden hard through corners than going straight. the Moto Guzzi seems to be happy doing anything I ask of it. if you guys are seeking that feeling from your earlier bikes, more power to you.