FuelCooler Posted October 21, 2007 Posted October 21, 2007 This will be part of my winter fun, so I will start the questioning early! I plan on adding the extra late model (2003 long frame) bracing to my 2000 short frame (the tubes that run from the lower pork chop, under the sides of the trans, to the engine). I have the late model parts in hand but I need to know 2 or 3 things. 1. Does anyone have late model cases to measure (+/- 0.015) the location for the necessary holes? 2. Are the early case castings different internally in a way (I would doubt) that would prevent this. 3. Anyone done this? Actually it might help if someone has a broken set of cases (Scura?) I could buy/borrow to measure and compare. FWIW-I was a machinist for 15 years, so be as technical as you like. Thanks in advance, Steve
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 Steve, I've gotta admire your ambition in tackling the task. It's been the topic o' many a fireside chat at the Guzzi rallies I've attended -- among the company of those longtime Guzzi Pro's with well established qualifications for comment! By your signature I can see that you have a sense of humor, so I rest assured that you won't be taking too much offense at a campfire-grade comment or 2 from Y'ers Truly? . . . By my reckoning and that of a few Pro's, adding the late model bracing could be done with the engine in the frame -- by a very skilled craftsman. To my knowledge, you'd be the first. Otherwise, the motor would have to come out for milling on the ol' Bridgeport, among other operations best suited for a variety of other great big walloping machine shop tools. But the obvious fly in the ointment here would seem to be the fact that you've ALREADY compromised the handling of this, the (IMHO) best handling of all V-11's, by crippling it with a mismatched sea-anchor wide-butt rear wheel and tire! So any tiny improvement in handling due to improved chassis ridgidity (that could only EVER manifest itself at extreme limits of the handling envelope, ONLY with a proper match of wheels and tires) would seem to've been forfeited -- and then some! -- before you start, n'est-ce pas?!?! So beyond the benefit of bragging rights and bar talk, this would seem the equivalent of fitting truck wheels and tires on a Porsche 911, and then bracing the chassis for improved handling at "inspired" speeds on challenging roads! But again, as a purely academic exercise for a long-time Pro machinist, I have to applaud the effort, and would eagerly await reports of your progress, my friend!
FuelCooler Posted October 21, 2007 Author Posted October 21, 2007 Steve, I've gotta admire your ambition in tackling the task. It's been the topic o' many a fireside chat at the Guzzi rallies I've attended -- among the company of those longtime Guzzi Pro's with well established qualifications for comment! By your signature I can see that you have a sense of humor, so I rest assured that you won't be taking too much offense at a campfire-grade comment or 2 from Y'ers Truly? . . . If having a sense of humor means that others laugh at me, then true... By my reckoning and that of a few Pro's, adding the late model bracing could be done with the engine in the frame -- by a very skilled craftsman. To my knowledge, you'd be the first. Otherwise, the motor would have to come out for milling on the ol' Bridgeport, among other operations best suited for a variety of other great big walloping machine shop tools. Yippie! I would be first! I would do it the right(-er) way...out with the motor and on to the Bridgeport. But the obvious fly in the ointment here would seem to be the fact that you've ALREADY compromised the handling of this, the (IMHO) best handling of all V-11's, by crippling it with a mismatched sea-anchor wide-butt rear wheel and tire! That like telling me my girlfriend runs worse in Stilettos then in pumps. So any tiny improvement in handling due to improved chassis ridgidity (that could only EVER manifest itself at extreme limits of the handling envelope, ONLY with a proper match of wheels and tires) would seem to've been forfeited -- and then some! -- before you start, n'est-ce pas?!?! So beyond the benefit of bragging rights and bar talk, this would seem the equivalent of fitting truck wheels and tires on a Porsche 911, and then bracing the chassis for improved handling at "inspired" speeds on challenging roads! My bike handles fine! I am not going for 'better handling' with this mod, I am going for a stiffer chassis to better cope with loading I am planning to add with engine mods and sticky tires. oh yeah and But again, as a purely academic exercise for a long-time Pro machinist, I have to applaud the effort, and would eagerly await reports of your progress, my friend! Thanks, it wont stop with this modification; I will ruin this bike yet. Cheers, Steve
Guzzirider Posted October 21, 2007 Posted October 21, 2007 It's been the topic o' many a fireside chat at the Guzzi rallies I've attended Your rallies seem a lot more sensible than the European equivalent, where fireside chats normally involve talking complete drunken bollocks!
FuelCooler Posted October 21, 2007 Author Posted October 21, 2007 So any tiny improvement in handling due to improved chassis ridgidity (that could only EVER manifest itself at extreme limits of the handling envelope, ONLY with a proper match of wheels and tires) would seem to've been forfeited -- and then some! -- before you start, n'est-ce pas?!?! I forgot to state the obvious: for handling, it is NOT necessarily a missmatch. A 180/55 on a 5.5 rim with a 120/70 on a 3.5 rim has been the wheel and tire combo on some of the most fabulous handling bikes made. All modern 600 sportbikes since about 1999. 851-888, Big Monsters, SS 900 and 1000 Ducatis. Some GSXR 750's came with them (they went back and forth with a 190/50 on a 6.0) and various Bimotas . Even the 1990-1995 ZX7 had that set up. And it got worse. A 190/50 on a 6.0 became the standard with the same small front on Jap liter bikes, MV Auastas, Ducati 916-999's, Aprilias(although some might have had 180's).
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 Hey, the campfire ain't gone out yet. . . More power to ya, Steve. I might point out that what wheel and tire width works best for bikes that weigh in the neighborhood of 150-175 lbs. less than a V-11, have somewhere near double the power and torque, carry that weight bias considerably farther forward than a V-11, have considerably longer swingarms, and rear wheel and hub assemblies that weigh less than half of the Guzzi aren't the ideal setup for V-11's -- as has been well established in practice on both road and track. I'd also add that what tires work well on the track are NOT THE SAME as what works on the road. In fact, for all practical purposes, they are very much mutually exclusive tire requirements, chief of which is that a racing tire is typically designed for ONE HEAT CYCLE ONLY. Riding this kind of a tire on the road is fraught with horrific compromises and certain danger when pushed hard on demanding roads. Of course, wide racing tires have promoted the trendy FASHION STATEMENT that found its way to Guzzi showrooms many years ago, handling compromises notwithstanding -- but you gotta give buyers wot they want, or they'll find it somewhere else. . . Going narrower on the rear wheel and tire has been well accepted and noted by many many riders on this Forum who've made the switch to narrower and realized the dramatic handling improvement in the process (myself included). AFAIK this is also 100% consistent with the qualified experience of the Guzzi Pro's who've also weighed in here on the subject of rear wheel and tire width. In other words, I think you'll find that probably everyone with a credible experience to draw a comparison on here has concluded that on the V-11, the wide-butt wheel and tire is a mismatch that compromises handling. Let me put it this way: If you had your suspension setup correctly, had a decent set of tires, and aggressively rode your favorite twisting mountain road (using all the tread to the edges) with your 180 on a 5.5" wheel, then ran it the same way with a properly matched 160/60 on a 4.5" wheel (all other parameters being equal), I reckon you'd arrive at the same conclusion, and there wouldn't be anything close to any doubt about it . . .
Greg Field Posted October 21, 2007 Posted October 21, 2007 I'm probably not credible and am a known contrarian, so it should surprise no one that I prefer the larger tire and wheel. I believe RacerX will be using it on his V11 racer, too. This may not be because it handles better but because you get an increment of increased cornering clearance. I believe he uses the same on his street LeMans. The wider tire was not fitted "for no reason." You may not like th compromises it brings, but there is a benefit that some find worth having. FC: I think I have one of those block at work. I'll check on Tuesday. If I do, we can discuss options such as lending it to you or measuring it.
dlaing Posted October 21, 2007 Posted October 21, 2007 As an alternative idea, one could fabricate some brackets to run from from the left pork chop to the starter mounting bolts, and from the right porkchop to the case. And then make some bracket like the one on the Japanese site http://www.motolavoro.com/ For a picture of it mounted, try this link http://www.pbase.com/coreyl/image/1284416
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 I'm probably not credible and am a known contrarian... By all means, may this Forum, and the Whole Wide World o' Guzzi's never lack for incredible contrarians! I always thought they were a requirement here, and I reckon I've made a pile o' me own incredible contrary contributions meself. . . Thankfully, we're STILL well able to make lots o' individual choices -- for wotever reasons we like. When it comes to cornering clearance, some of us (myself included) have achieved considerable additional clearance with a custom, longer than stock eye to eye length on the shock, balanced out with correct sag settings achieved with up-rated springs at both ends, and rake and trail balanced out via fork height in the triples. I believe RacerX will be using it on his V11 racer, too. This may not be because it handles better but because you get an increment of increased cornering clearance. I believe he uses the same on his street LeMans. The wider tire was not fitted "for no reason." You may not like th compromises it brings, but there is a benefit that some find worth having. When Todd had me check the firmness on his LM by sitting on it, I found it was "racing-hard" front & rear. I wouldn't be able to tolerate it for longer than a few hours on the roads I like to ride, but that's just me. If he doesn't have a custom length or adjustable ride height on his shock (can't recall), I'd be pretty surprised. . . Long as we're talkin' contrarians and compromises, I would point out that Racer X (Todd E.) ain't exactly y'er garden-variety rider, and is without much question far more capable of working with extreme handling compromises than the likes o' most riders, myself certainly included. A few years back he was racing a Dondolino -- and quite respectably, as I recall . . .
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 Here's wot I was lookin' for. Worth a re-post here, methinks. . . Street vs. Race Choosing the right tire for the job Street vs. Race Choosing the right tire for the job By Andrew Trevitt We know what you're thinking: Those namby-pamby street tires are for weenies, and the DOT race tires work way better on the street, right? Wrong. While you're struggling with a stone-cold Supersport toss-off that's rock hard from too many heat cycles, your buddies on their high-performance street tires will be long gone. Race tires are specifically meant to do one thing: Stick like glue, for one heat cycle. To that end, they are designed with an entirely different philosophy from street tires, and those differences make them unsuitable for street use. One obvious difference is most race tires have fewer grooves for more grip. And while this is great on a dry road, riding in the rain can get pretty hairy. But this is just what you can see, and it's perhaps more important to know what's going on inside the tire to fully understand the differences. Max Martin, with Avon Tyres, says its Azaro Supersport bun is designed with a high arch and very high crown, particularly the front tire. This makes a race bike steer quickly (at the expense of stability), and gives more surface area on the side of the tire for more traction at full lean. The Azaro Sport street tire has a rounded profile, which puts more tread on the road when the bike is straight up for better wear, as well as being more stable and allowing easier line changes in midcorner. Put the race tire on the street and it will wear quicker due to the pointy profile. Martin also pointed out differences in casing design, with the Supersport tire having an additional ply and tighter winding for higher cornering loads. However, on larger bumps found on public roads, this extra rigidity will have the race tire chattering earlier than would the softer and more compliant street tire. Sport Tire Services' Dennis Smith points out that the Dunlop D207 Sportmax is designed to work correctly at the reduced temperatures found on the street, as opposed to the higher temperatures found on the racetrack. And that you'd almost never be able to generate track temperatures during a street ride to take advantage of the extra grip offered from a race tire. Smith also mentioned the material and production costs are totally different for each type, with the race tires costing significantly more than the street tires. According to Mike Manning of Dunlop Tires, the D207GPs utilize a "cut breaker construction," in which the plies are overlapped to give good side grip. Compare that with the D207 Sportmax, which has a "jointless belt construction," giving more stability and a smoother ride. Manning also added that a street tire's rubber compound is designed to go through more heat cycles, as well as having silica added to give better wet grip. [Trevitt's bottom line:] So let's see, a street tire will generally have better wear, more stability and superior wet-weather performance compared with a race tire, offer similar grip (and most likely more) at real-world tire temperatures, and give constant performance over many heat cycles-all for less money. Sign us up. SOURCE: http://www.sportrider.com/tech/tires/146_0..._vs_race_tires/
belfastguzzi Posted October 21, 2007 Posted October 21, 2007 Your rallies seem a lot more sensible than the European equivalent, where fireside chats normally involve talking complete drunken bollocks! Hmm... going by Ratchet's telling of events, there doesn't seem to be any difference to me...
Baldini Posted October 21, 2007 Posted October 21, 2007 If you're going to the trouble of doing it at all, have you considered more elegant ways to brace the frame/sideplates. I think the Guzzi method is pretty slapdash & ugly. Sportis had a brace between spine & top of gearbox. Ratchethack - where did "racing" tyres come into the argument? I'm with you that the narrower tyre/rim handles better than wider - no question. But this also varies tremendously with type of tyre - a sharp profile helps the sluggish turn in you get with fat tyres. Greg - Using a wider tyre may increase ground clearance at lean but I don't beleve that is why Guzzi changed to it. I agree w Ratchet - fashion. There are better ways to engineer increased ground clearance if that was an issue - & I don't think it was for Guzzi or the vast majority of customers. Most modern bikes make a hell of a lot more power than the Guzzi & aside from fashion may have more need of the extra material under hard acceleration. Guzzi just needed it for sales. A concern I had was narrower fitment must stretch further to fit rim width, flattening profile to some degree = it would run off tread edge earlier than a wider tyre of same type. There's also much less availability in narrower widths. KB
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 Ratchethack - where did "racing" tyres come into the argument? I'm with you that the narrower tyre/rim handles better than wider - no question. But this also varies tremendously with type of tyre - a sharp profile helps the sluggishness you get with fat tyres. Using a wider tyre may increase ground clearance at lean but I don't beleve that is why Guzzi changed to it. I agree w Ratchet - fashion. There are better ways to engineer increased ground clearance if that was an issue. Most modern bikes make a hell of a lot more power than the Guzzi & aside from fashion may have more need of the extra material under hard acceleration. Hi Keith. Yeah, I got in a hurry, and your point occurred to me as I was on my way out the door. As my post above unfolded -- stream-of-consciousness-wise -- I failed to make the connection between racing tires and "Bloat-o-Bling" wide street tires. As you've pointed out above, racing tires are WIDER than street tires, but they're also much sharper profile than wide-butt, round profile street tires, not to mention the entirely different construction and compounds. . . ergo the melon-on-stilts handling of a wide, round profile street tire -- even when mounted on a rim designed for it. So to respond to your Q, I reckon the INSPIRATION behind the "Bloat-o-Bling" wide-butt tire fashion trend for road tires came from racing, so we're "blessed" with late-model V-11 Guzzi's that handle worse than the earlier model narrow-rim models, in accordance with a market necessity to cater to buyer priorities. . . and let's face it -- looks trump pretty much everything on the showroom floor. . .
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 Hmm... going by Ratchet's telling of events, there doesn't seem to be any difference to me... An astute observation, BFG.
Guest ratchethack Posted October 21, 2007 Posted October 21, 2007 If you're going to the trouble of doing it at all, have you considered more elegant ways to brace the frame/sideplates. I think the Guzzi method is pretty slapdash & ugly. Sportis had a brace between spine & top of gearbox. Yes, indeed. The highly sought after, and oh-so-rare "piastra colleg". I've made one up and installed it. IIRC, Docc put one in same time I did, about 4 years back. "Short frame" sports came with the welded-in frame tang to attach it installed -- but with no plate. Does it do anything at all? Without a strain gauge, I reckon it's impossible to tell. Apparently Guzzi didn't think so, or they'd have saved us the trouble. <a href="http://www.v11lemans.com/forums/index.php?...c=1797&st=0" target="_blank">http://www.v11lemans.com/forums/index.php?...c=1797&st=0</a>
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