chasdom

Thanks for the info and the encouragement.

Hi dlaing, thanks fo the good info. on the swing-arm lengths. Actually, I wished I had used a V50 as the donor bike, for a variety of not terribly important reasons. There's just something about 500cc's if you know what I mean. As I mentioned above, I too have read the axiom about max efficiency at max torque, but again, if you get a chance go to the Craig Vetter Mileage tests, and what they found there seems in contravention to that. In essence, the slower they had 'em popping, the better mileage they got. After more time on this project/patent than I'd care to admit, I've learned a number of things - not the least of which is some of the 'conventional wisdom' out there, may be off the mark. The airplane fuel mixing is interesting - but I have no doubt I'd end up cooking this little goose! That's an art... and in that case ... I'm not Picasso! Anyway, one of my thoughts of the last year, is that along with our standard gearboxes, virtually all road bikes should have either a very tall high gear, or a two speed rear-end/final drive so that under the right conditions, we could lope along at lower rpm, and save a bit o' gas. Anyway, thanks again, and oh - another advantage of a V50 is the carb... inferior to fuel injection, save when a simple peasant like me wants to tinker out in the garage. Thanks Again

Hey Raz: To give you an exact answer is impossible, as the whole thing is an empirical process. Yes, on the one hand I've read before that maximum "efficiency" is at maximum torque rpm. HOWEVER, in real world circumstances taht may not be the case, as posited by Craig Vetter in his experience with his fuel mileage contests of the early eighties. If you're not familar with them, check them out by simply searching for Craig Vetter Mileage Contest, and there's a ton of information there. Basically, what the contestants empircially found was that high gearing/low rpm at then highway speeds (55mph for the era) were the most efficient. This seems in direct contravention to "conventional wisdom", but alas many of those guys were getting well over 200mpg, and several bested 300, with the best example at 471mpg. As to picking the goose - it was probably a poor choice overall, but I thought the aesthetics of the bike would help. From what I have learned, today I would go with either a 500 Kawasaki or preferably Suzuki parallel twin, and just swap sprockets. Yes, a 125 or 250 would get better mileage - but what good would that do if nobody would ride them? So my theory is - settle for a bit better than 100mpg at freeway speed, but have enough "snort" that the bike would have some roll'on power, and decent top-end - more or less 120- 135, so that a fellow could run with his pals and no get left on a weekend, but still have a PRACTICAL commuter vehicle for weekdays. Gas is cheap now - but who really believes that's going to last long? Charles, I'm curious what rpm you are targetting for the engine and what speed you'd like at that rpm. It seems to me a Guzzi is not the best engine to make mpg records with, though like with tuning, getting relative enhancements is easy and maybe your fairing is most of the trick. My experience is you got to exceed 4000 rpm to get best mileage with my injected 1100. On the other hand, mpg is only my second or third priority so I haven't really experimented a lot with that in focus.

Hey Chris, I went and pulled up the page from Guzziology on the small block gearing and unless I'm being a "blockhead" which is entirely possible as sometimes gear ratios seem counterintuitive to me - when I take into account primary, high gear, final drive etc... it's almost like looking in a mirror with a mirror. I can be a wee bit slow! Anyway, just a cursory review suggests to me that the bike is already geared about as high as the small blocks go. I did add a slightly higher speed final-drive from a 500 (I don't recall the exact model offhand) that was about twenty years old, and I got an additional six percent. I also had laced (Buchanon Spoke and Rim) 21" front rim to the back wheel, and then covered it with disks - for an additional six percent or so. Still, I probably may just have to go to the big motor and transmission.

Hi Chris thanks for getting me the primary ratios on the small blocks. you're idea of actually just "swapping" gear boxes is an intriguing one - if they're compatible with the later model Nevada, and also doing some back of the envelope math to see how much "taller' that would get me. As to the 'Baja", it sounds like a 'fix' with an added set of problems. Although to date on the project - every time I do something to this bike, it's like Newton's third law of physics ... they're ALWAYS a reaction in the form of a NEWLY created problem! Oh... to have the resources to be able to start from scratch... Oh, I had no idea Guzzi ever even made a "Baja" ... that's great. Coincidentally I had one of the 'orignal' Bajas, that is back in 1971 I bought a brand new Harley Davidson (Aermacchi) 100cc Baja. Sold it about ten years ago as it was literally out in the barn for a couple hundred bucks. Probably a mistake. Although a friend told me he saw one in the area - most probably my old one - so maybe I should go buy it back. It would probably make a fun little cafe racer. Oh well - again, thank you for the good info. and I will check it out. Chaz Charles , the gearing on the small blocks is altered by changing the primary gear sets .these are the two gears that are between the clutch housing and the gears per se.The final drive 's are all the same I think as are the gearbox ratio's. The slines on the shafts vary according to the vintage so a partial sawp may not be feasable. If you look in Guzziology , chapter 14-11 to 14 15 covers all the small block gearing options . They are as follows 13/24 for v 35 13/23 for v 35 imola and gt 12/24 v35 111. ntx and early tt 12/25 late tt and ntx 13/24 350 nevada 14/23 v 50, v50111 and custom 15/22 v50 monza 15/22 monza 11, v75, v65 , sp, custom, gt and florida 16/21 v65 lario, florida,750 targa, nevada 750 and 750 sp 14/23v65 tt and ntx The easiest way to go would be to simply swap the gearbox for one with the desired ratio and as the boxes are pretty cheap and available second hand( at least here in europe) that would be a cheaper solution than getting a big block and starting all over again ! another way to go is also to adapt a big block swinging arm to the sb frame which is the option the factory took with the Baja desert racer- They only hand built 17 or so of theses and the swinging arm mounting points on the gearbox were a constant failiure point in the design so they grafted on the big block one. I'd say that the larger and stronger UJ was also a consideration as they are known to fail dramatically in the small blocks and especially on the enduro models as the swinging arm is more steeply angled due to the longer shocks. I have a few baja pics if you are interested Chris

Hey "JC" thanks very much for the encouragement. Also, I checked out your link, and my compiments on your shop as it's first rate. Tell me- did anyone see what kind of bikes are the escourts for our P. Obama llimosine as he spins around your neighborhood...? It would be nice if they were Guzzi's, but I suppose they're Beemers, which is fine. I just hope he didn't haul some Hardley's over the pond! Again, best wishes, and I do hope all is well in Belgium.

Hey Raz, thank you a bazillion, as you are a wealth of information, or at least a wealth of possibilities... now I have LOTS more research, but at least a few ideas to perhaps ask the right questions - thanks again, Charles

Hey 'Guzzirider" thanks very much for the link, but by the time I got to it Friday it was gone, thanks again, Charles

As a former owner of three V11 series bikes, I'm just wondering if anyone out there has done any 'gearing up' on their V 11 or other 'large block' Guzzi. My reason is that I'm presently working on a prototype for a fairing I've developed which is an improvement (with full lock-to-lock) steering capability, upon the dustbin fairings of the 1950's, but I erred in using a small block Nevada, for which gearing options are near zero. I have used a circa 1980 rear-end off I believe what was one of the old V50's, and also a 21" rear tire, but my rpm is still far too high for the power reduction allowed by the fairing. So if anyone has experimented with gearing on the bike block bikes, I'd love to hear from you. Also, has anyone out there ever lengthened a driveline and housing? Would love to know. Oh, if you're curious, you can see what I'm up to at my personal project page at toytotransportationcom my goal is to have a practical 100mpg full-sized bike. Thanks for your time, Best Wishes, Charles