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V11 Suspension.......Or is it Geometry


raceboy

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A big, hard SHAFT is one of the reasons why I like the Guzzi....

 

Like the old saying goes....... "It's Hard To Be Humble With A Shaft Like Mine" or something like that.

 

:thumbsup:

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Its a swallower guzzi,search the net and you will find that they build some amazing guzzis for BOTT racing here in europe.

 

2 brothers from Holland made them and i was talking to one of the brothers a few weeks ago on a cafe racer meeting in Holland,while looking at my Daytona.

 

He is the one building the unfinshed bike in the pics,it felt rather good that he was intersted in my bike and how we made and modified it with performance and handling in mind not just the looks.

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Guest ratchethack

Has anybody here noticed that moving the bevel drive to the back of the OE gearbox makes it necessary to move the swingarm pivot rearward (the wrong direction), and that because of this, the bevel --> chain conversions all seem to have great wallopping canal boat wheelbases? This has to be the biggest drawback, and the reason it never caught on. The OE wheelbase of a "short frame" Sport is m 1,471. Though I reckon it can be done, I can't imagine trying to stuff something on the order of ~m 1,480 wheelbase through the twisties -- OTOH, I'll bet that canal boat stability is a treat at the drag strip, or anywhere else on the straight >100 MPH. :huh2:

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Hack, I have a Griso and even though it has a wheelbase way over your 1480mm line in the sand, it actually handles the twisties very well. Yes, a shorter wheelbase can be a good thing, and I would not mind if my Griso had a shorter wheelbase. But wheelbase length is not all there is to good handling and I have ridden a few bikes with longer wheelbases and they can handle very well. The only place I have found it to be a serious drawback is tight corners at lower speeds like when doing parking lot racing. The long wheelbase just won't let the bike turn as tight as you want. But the trade off can be better handling in faster corners.

Just food for thought.

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Guest ratchethack
Hack, I have a Griso and even though it has a wheelbase way over your 1480mm line in the sand, it actually handles the twisties very well. Yes, a shorter wheelbase can be a good thing, and I would not mind if my Griso had a shorter wheelbase. But wheelbase length is not all there is to good handling and I have ridden a few bikes with longer wheelbases and they can handle very well. The only place I have found it to be a serious drawback is tight corners at lower speeds like when doing parking lot racing. The long wheelbase just won't let the bike turn as tight as you want. But the trade off can be better handling in faster corners.

Just food for thought.

That's mighty interesting, Quasimodo.

 

What's the wheelbase of your Griso?

 

The wheelbase of the Griso 1100 is m 1,554, according to Guzzi:

 

http://www.motoguzzi-us.com/Nuovi_modelli/...p;pagina=scheda

 

Quite the curious choice for parking lot racing, innit?

 

But then, I reckon there's always somebody who's gonna consider it amusing to shoot the rapids in a canal barge. . .

 

Then we have barstool racing, tractor trailer racing, swamp buggy competition, and all manner of monster truck behavior that all seem to be quite popular, too. . . :whistle::huh2:

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Has anybody here noticed that moving the bevel drive to the back of the OE gearbox makes it necessary to move the swingarm pivot rearward (the wrong direction), and that because of this, the bevel --> chain conversions all seem to have great wallopping canal boat wheelbases? This has to be the biggest drawback, and the reason it never caught on. The OE wheelbase of a "short frame" Sport is m 1,471. Though I reckon it can be done, I can't imagine trying to stuff something on the order of ~m 1,480 wheelbase through the twisties -- OTOH, I'll bet that canal boat stability is a treat at the drag strip, or anywhere else on the straight >100 MPH. :huh2:

 

Actually, from the closeup

DSC02805.jpg

 

it doesn't appear that the pivot was moved so much rearward, but that attention was given to keeping the pivot on the same axis as the countershaft sprocket, so that there is no need for chain slack!

 

BMW went this route on their latest off-road bike, iirc. Kind of a big deal because the idea has always been disparaged as "too expen$ive for production" and therefore not worthwhile, while anyone w/ a dirt bike will tell you that the large amounts of chain slack required because of the long swingarm & large suspension travel is a real PITA.

 

Once the sprockets are on the same centers as the swingarm pivots & axle [by default for the chain driven rear wheel, not so for our shafties], it becomes a trivial matter to enclose the chain for better lubrication & protection from dirt, and voila' - a lighter, low-maintenance drive system than our shafties. No need for fancy floating final drives & parallelogram linkages either. Well worth an extra cm or so of swingarm rearwardness, I think.

 

Back on the topic of losing weight from the back 1/2 of our bikes and Racerboy's project: 3 words, 6 syllables that you'll here in car racing all the time, but not at anytime in conjuction w/ our Guzzis: CF driveshaft.

 

Ride on!

:bike:

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Hack, my point is that in normal sport riding on the road, the extra 4 inches (roughly) of wheelbase is not a problem. It is only when taking tight, slow corners that you really notice it. A Griso is not the best choice for parking lot racing, but it is still fun and others do it on harder bikes then a Griso (like Harley baggers and V-Rods). Sometimes the reward for doing something isn't based on how easy it is but rather how hard.

I have other bikes that I also used for parking lot racing, but unfortuneatly the parking lot racing series I used to do has shut down. So now I race my SuperMoto in local races. Still huge fun, but not something to do on ANY Guzzi.

I don't think the driveshaft is that big a part of the weight, but I have not weighed one. A Guzzi D/S is much shorter and smaller in dia. then a Car D/S, so that may be part of it. Besides, I would rather have Ti then CF.

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Actually, from the closeup

DSC02805.jpg

 

it doesn't appear that the pivot was moved so much rearward, but that attention was given to keeping the pivot on the same axis as the countershaft sprocket, so that there is no need for chain slack!

 

BMW went this route on their latest off-road bike, iirc. Kind of a big deal because the idea has always been disparaged as "too expen$ive for production" and therefore not worthwhile, while anyone w/ a dirt bike will tell you that the large amounts of chain slack required because of the long swingarm & large suspension travel is a real PITA.

 

Once the sprockets are on the same centers as the swingarm pivots & axle [by default for the chain driven rear wheel, not so for our shafties], it becomes a trivial matter to enclose the chain for better lubrication & protection from dirt, and voila' - a lighter, low-maintenance drive system than our shafties. No need for fancy floating final drives & parallelogram linkages either. Well worth an extra cm or so of swingarm rearwardness, I think.

 

Back on the topic of losing weight from the back 1/2 of our bikes and Racerboy's project: 3 words, 6 syllables that you'll here in car racing all the time, but not at anytime in conjuction w/ our Guzzis: CF driveshaft.

 

Ride on!

 

:bike:

 

I think that is a interesting idea. The counter shaft in axis with the swingarm pivot is a good idea but as with most design changes it has advantages and disadvantages. You've mentioned some of the adv., but one disadvantage (compared to a more conventional chain drive arr.) is that in a well designed chain drive setup you actually get the rear wheel pushed down into the asphalt under accelleration for better traction. I do not believe that this setup allows that.

I also like the idler setup the new Buells have.

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Guest ratchethack
it doesn't appear that the pivot was moved so much rearward, but that attention was given to keeping the pivot on the same axis as the countershaft sprocket, so that there is no need for chain slack!

 

. . .Once the sprockets are on the same centers as the swingarm pivots & axle [by default for the chain driven rear wheel, not so for our shafties], it becomes a trivial matter to enclose the chain for better lubrication & protection from dirt, and voila' - a lighter, low-maintenance drive system than our shafties. No need for fancy floating final drives & parallelogram linkages either. Well worth an extra cm or so of swingarm rearwardness, I think.

Roger all the above, Skeeve, and yet none of the Swallower Guzzi's seem to've taken advantage of co-axial swingarm pivot and countershaft by making use of an enclosed chain. In fact, looking at the photos of the Swallower Guzzi's, one swingarm has a considerable chain drag pad on it, and even an idler roller to control chain slack underneath. Judging by the relative proportions, it appears they've all got the swingarm pivot moved well aft from the OE V11 location, and that they're also running longer than OE V11 swingarms.

 

On the face of it, no way around the dimensions of the OE Guzzi 5-speed gearboxes as used on the Swallower Guzzis (or even the shorter 6-speed, for that matter), and the fact that adding a pinion on the back of either one with the dimensions of requisite bearing support, and then a crownwheel aft of that all takes up space, pushing the location of the swingarm pivot farther back than the OE v11 location in order to be co-axial with the countershaft. . .

 

Just an observation. :sun:

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Has anybody here noticed that moving the bevel drive to the back of the OE gearbox makes it necessary to move the swingarm pivot rearward (the wrong direction), and that because of this, the bevel --> chain conversions all seem to have great wallopping canal boat wheelbases? This has to be the biggest drawback, and the reason it never caught on. The OE wheelbase of a "short frame" Sport is m 1,471. Though I reckon it can be done, I can't imagine trying to stuff something on the order of ~m 1,480 wheelbase through the twisties -- OTOH, I'll bet that canal boat stability is a treat at the drag strip, or anywhere else on the straight >100 MPH. :huh2:

 

Well if you look better, Eric used a Hossak front setup, so the wheel can be very close to the alternator.

And he used a 5 speed gear box, when he made it the six speed wasn't even born. I put a six speed in his shop, and with a new rearcover the chain conversion could be integrated in the gearbox. It's that he doesn't have the time, beause he is to busy.

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Moving the front wheel closer to the motor and the rear wheel further back seems like going in the right direction to me. Too bad people like that don't work at Guzzi any longer.

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Guest ratchethack
Well if you look better, Eric used a Hossak front setup, so the wheel can be very close to the alternator.

And he used a 5 speed gear box, when he made it the six speed wasn't even born. I put a six speed in his shop, and with a new rearcover the chain conversion could be integrated in the gearbox. It's that he doesn't have the time, beause he is to busy.

The Hossack front end hadn't escaped my attention, Paul. Properly tuned, this could certainly do wonders for shifting overall weight forward, offsetting one o' the OE Guzzi Big Twins' biggest chassis compromises.

 

Interesting about the idea of an integrated bevel drive with a 6-speed rear cover. Might be just the ticket to best balance the whole contraption without having to make a war canoe out o' it!

 

Would really appreciate looking at some measurement stat's and a proper handling analysis on one, should one ever be made! :race:

 

post-1212-1248201638.jpg

 

Maori War Canoe

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Paul, I was comparing SWB & LWB V11's, not Daytona.

 

The V11's are SWB = 25 degree rake, LWB = 26 degree rake, same length frame.

 

At least that was the conclusion from carefully measuring one against the other in my driveway. :nerd:

 

Ah ja. And then, why did they shorten the tanks then? That's what I'm asking meself since I've read your post.

 

Hubert

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Guest ratchethack
Ah ja. And then, why did they shorten the tanks then? That's what I'm asking meself since I've read your post.

 

Hubert

Just a hunch, Hubert, but perhaps they shortened the tanks to clear the fork stanchions at full lock, made necessary by the change of rake of one degree, (25 degree rake Sport --> 26 degree LM) which put the stanchions in contact with the tank (could well be the case with the frames being equal overall length). And/or maybe they changed the tank mounts and/or seats?? I reckon they'd hardly have to consider shortening the tanks if they had actually gone to a longer frame on the LMs?? :huh2:

 

FWIW, since my tank has been swelling from ethanol-adulterated fuel in it for 10 years, it's been contacting the stanchions at full lock for a few years now. Prior to that, there was always clearance.

 

We measured my 2000 Sport frame against a 2004 LeMans, from the banjo union at the oil breather behind the steering head, back to an identical point on the rear subframe. Same distance. The frames looked identical from the banjo forward, same distance to the steering head, but impossible to see a change of 1 degree of rake.

 

Hope this helps. B)

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