motoguzznix

David your first statement is one I doubt very much. Tire development progress occured to handle the increased power of todays engines. With the fraction of engine power of an ancient bike the lower tire friction will outweigh the better handling capabilitys of a todays chassis. An ancient racing bike is optimised to make the best of the given combination engine/chassis. Underpowering a chassis with large sticky tires means you cannot apply the driving style it is made for. There is a good example: 5 Years ago the "Klausen pass memorial" in Switzerland was reinvented - it was a classic mountain race prior to ww2. The mountain road is identic to the ancient road. It was only allowed for pre ww2 racing bikes to participate. These bikes were faster and had better tires than the original bikes in the 30s. Even though the road was a gravel road in the 30s and today there is a sticky tarmac applied except some cobblestone U-turns and good drivers drove up the mountain, no one could beat the last record time of Tom Bullus in the 30s. And they really tried!

Polebridge If your clutch plates are assembled vice versa like Brian stated, it should slip soon. With increasing wear of the clutch plates, the springs don't compress the plates any more and begin to slip. You can see the contact marks on plate and flywheel. If there is no slipping, it is more likely that the rivets connecting hub and outer part of the clutch plate are loose at least on one plate. However, tearing apart engine and gearbox to get access to the clutch is a must. Let as know what happend...

Gray The V11 sports extremely restrictive mufflers an thus benefits a lot from the front crossover - the torque hole around 4000 is not so deep in fact. But with open Lafranconis the benefits will be much smaller if there are benefits. Your specs sound powerful. Has the dyna ignition you use an ignition advance curve? I only know about a Dyna to replace the contact breakers and this system works with the mechanic advance curve given by the distributor.

Gray Mistral offers a header pipe set with front crossover with 42 mm ID. For Tonti frame Guzzis. The 1100 Sport headers have the right diameter and I would not expect very much powerwise from a front crossover. Worse will be the use of the much smaller Cali header tubes, with or without crossover. The V11 headers may will not fit the Tonti frame very good - check that first. My opinion: restrictive mufflers benefit more from the front crossover than open mufflers.

Steve Me too - I like the handling of the old short frame KRs. I installed that triangular bracket too and could not find any difference in driving behavior. I also installed the front bracket from the newer model- no difference either. I would also like to install the lower bracket with the lower rails to the engine - but welding on the engine block in that area could be some risk as this is the area of the rear crank bearing. If there comes up a good idea on that subject, I am the first to upgrade my frame.

Some comments on the pictures above: The Mike Ritch piston is the only piston designed to cope with the V11 combustion chamber shape - it follows the chamfer in the stock chamber thus allowing a real squish area and a CR quoted 10.5:1. Very good. The FBF piston is flat on top outside and does not cope with the chamfer of the combustion chambers - so you get 11:1 CR without a real squish area. To remove the chamfer you have to mill approx. 1 mm off the head. This will further increase the CR supposedly to around 12:1, which is maybe too much even for a twin plug installation to cope with. No good. The stock piston is the same design like the FBF and even in stock configuration a lot of V11s tend to ping, resulting from the design without squish-area. My KR had a measured CR of 9.15 from new and pinged sometimes! When optimising the squish area by milling 1 mm off the heads and shortening the cylinder barrels by 0,45 mm to deck the pistons with the cylinders, the CR will climb to approx 10.5. Very good, will work fine on single plug with mapping to suit. Same result as with the Mike Rich piston, but the combustion chamber shape is slightly better due to the lower piston crown. But the Mike Ritch piston will probably work without any machining of head and cylinder barrels. But the stock piston is a good, stout item, maybe a little heavy but adequate for the job in a street engine. For a race engine, the weight will get more important. The conclusion for me: the least desirable design is the FBF piston - you would be better by modifying the heads and barrels and retaining the stock pistons.

Greg This is exactly what I'm after on my V11. Due to an incident this summer my efforts were stopped half way. I would like to use a short duration and high lift cam like Dynotec or HTM offer for the Guzzis. But to get the full benefit of such a cam, the intake port has to be reshaped for flow up to 11 mm valve lift. By now, there is no increase in flow above 8 mm lift. Even the stock V11 cam opens 10.5 mm! To get optimal squish, I shortened the cylinder barrels by 0,45 mm to get the pistons on top. This amont may be different on any engine. Turning to the heads, the area with a flat chamfer on the outside of the combustion chamber has to be removed completely. This will occur when approx 1 mm is milled off the gasket surface of the heads. The CR will climb to approx. 10.5:1 . Valve to piston clearence may get too tight and must be checked. In case of problems the pockets in the pistons need to be milled deeper. This will be my next steps when time allows it and my new house with workshoop is ready.

I tried this double-X-over on my 950 cc Lemans2. Especially the lower rpm range was very much improved. On top I can't say - its a long time ago. But not worse for sure.

The Mistral H-over (good idea, that name) costs power even on completely freeflowing mufflers. The measurements by Doug Lofgren are with open mistral mufflers, the measurements by Moto one are with open Leovinci cans and Gregs Billybob sports open FBF cans. I agree with the smooth running using a crossoverless exhaust as I tried this on my LM2 together with open Lafranconi competiziones some years ago. Peak power was lower by feel, but no torque dip - did no dyno test at that time. My best crossover was homecooked and looked alike: The idea behind it was that every cylinder can make use of both mufflers, like it was intended with the V7Sport Crossover. While the V7S part is down on flow, my crossover is much better in flow characteristics. Power was promising, should once be developed further.

Hi Greg bypassing that private discussion I want to return to our technical issue - the torque flat spots. One thing is interesting on your second power graph and maybe typical for the mistral crossover - there is no power increase above approx. 5500 - 6000 rpm. And this is not good for an engine that is designed for 8000 rpm because the engine is not capable to do what he's designed for. This is normally not the case with the Stucchi crossover. Maybe you should give it an other try on the dyno with remapping to suit.

Greg For me it is still hard to believe that the measured Power/torque difference is caused by the filter element. It seems more to be related to the differences in the air box design. I beleive the difference caused by the filters themselves will be unmeasurable. Swap the filters in the airboxes and measure aigain to be sure.

In the meantime I performed the mods following the lower drawing on the scetch. The effort in welding and sawing was much greater than the first mod and a really sweaty job. The exhaust note is now wonderful. Smoother than straight through pipes, not so hard, but noise level increases with throttle opening and higher rpms and gives a very nice sound. Not relly quiet but far from noisy. Acceptable for long trips on the bike. Removing the steel wool makes the can neither noisier nor flow better because the end tube is not open to the steel wool packing. The cause for the steel wool is the entering gasses pass through the big tube until they are reflected and dampened by the steel wool. When they arrive there they are still very fast and hot, so this is the area where most of the energy of the exhaust is dissipated in the original design. David I was also thinking about a change like you described above, but I think the next step must be to increase the diameter of the end tube. But every change in the can design that exceeds my first simple mods is not worth the effort. You would be better by building a silencer from new than modifying the stock one.

Sorry but I cannot see the pictures on my Computer - is there anybody out that can provide them in a different format? Would like to see how the teardrop shape is executed. Thanks

Here is the link where I posted my mods on the standard cans: Unpacking the cans There are power graphs added that show the gains of my mods. To make things clearer a scetch with my mods: The upper drawing on the scetch is straightforward to realise. The dotted areas of the internals of the cans should be removed. If you are experienced in sawing and welding the job can be done within two hours. After pulling the cover saw completely through behind the front welding seam. The rest of the mods in the 1st chamber can be done by sawing partially through from the up- and downside. For the mods in the 3rd chamber I cut' a square window on the upper side. The window is cut on three sides and the sheet metal bent away. Although the inner can is in stainless steel, it can be welded easily with a non stainless wire as the welding seams are invisible and there was no rust inside my cans after two years.

Thanks Phil for your explaining! I think max power will not increase on a V11 when performing your mods with the airbox because of the limited breathing of the V 11 intake port. Supposedly the V10 4V design flows significantly more air and therefor can make use of the better capability of the modified airbox. This might be different for gains in the lower rpm area. When I was on the Dyno with my KR V11, I compared the stock airbox with the snorkels to a modified one with 6 holes of 25 mm on the top and could not measure any difference powerwise. The mixture on the top was almost the same and got richer from 6000 to 8300. This lead me to the conclusion that the airbox was not the bottleneck in the V11 system. Here is the graph whith the two Leovinci measurements with an without holes in the airbox. Exhaust was an open leovinci cans with Stucchi Xover. I will give your mods a try, but first I want to fix the intake port issue.

I try to explain things from my point of view (not knowing if I'm right): The most important thing in the exhaust is the shock waves. These can best occur when the exhaust sytem has no restrictions. A restricted muffler and/or crossover deminish the effect of the shock waves, but may even out the power curve. This was evident during my measurements on the dyno comparing stock muffler with my modified less restrictive mufflers. Whenever the exhaust wave comes to an open end, a depression wave is reflected back to the exhaust valve thus helping to clear the cylinder. This effect takes place several times during one cycle. But where is the end for the exhaust flow? Maybe the stock Xover which is an empty chamber? The 3rd chamber in the stock muffler where the exhaust tube ends? How does a crossover like the stucchi influence this system? The first chamber of the muffler in my modiefied system? How can you predict any effect taking into account all these conditions? Even a correct prediction might be caused by other effets like thought at. But the real problem seems to be in the intake system for me. First the anabilty of the intake port to allow sufficient flow at valve lifts higher than 8 mm see here Second following the discussion about gas speed I think the intake port is too big. It would be better to make a smaller port flow better to increase gas speed. The flow bench graph above shows the LM2 smaller port flow better than the bigger V11 port at higher lift. Using heads and pistons of a Cali 1100 could realise this easyly. A similar effect could have a camshaft with shorter duration and fast opening rate off the seat. When the port flowed at higher lift, more liift would be benefical. Dynotec or HMB offer camshafts who follow this route. The combination of the two would be very successful eliminating the flat spot. High intake speed generates higher pressure when flowing against the closed intake wave so starting the flow better when the valve opens again. Shorter duration of exhaust and intake allows to make use of the explosion longer and to increase the real compression stroke after the intake valve is closed. Both increase the efficiency of the engine. Shorter overlap between intake and exhaust decrease the losses of charge at lower to medium rpms. Optimising the squish and the increased CR that follows doing this makes the charge burn more efficiently ending in an engine that should have come from the factory.

Remove all your additionnal electrics from the bike! This is always the first things to suspect! If the fault still exists, I would suspect the voltge regulator.

Concerning the X-over of the V7Sport, I can make a comment as I own one: There are two separate crossover pipes that protrude into the exhaust pipes and so reduce the freeflowing area of the pipes. This is a worst case situation for the exhaust föow and causes power losses all over the rpm range. When I removed the protruding parts of the crossover pipes, power made a substantial step upwards. Not backed by Dyno measuremants, only by feel. But the crossover then is more of a conventional Xover like on any LM 123. David I would be careful with these predictions.You might be far from the truth and on the Dyno there might be a lot to learn in that area. For any 4stroke engine, backpressure is bad for power. Of big influence is the tuning length of the exhaust pipe. This has to be taken into account for comparisons. The fuel can be mapped independently for each cylinder, the ignition timing not. For the fuel, there is a base map for both cylinders and an offset map for the right one. Wideband lambda controllers are available by several sources, I use the Dynojet wideband controller. Works well with good results, my posted lambda measurements are made by using it.

This is right, but only for one engine that is tuned to suit the air/fuel requierement. If You change the amount of air that passes through the engine, the amount of fuel has to change too. Every change in the exhaust/intake/CR area changes airflow and thus mixture lean/richness. When there were a MAP sensor added to the system, some self adjustment would be posible. No, I don't think so. Different A/F ratio in the area of the flat spot did not cure the flat spot, see my graphs posted above. David My graph above is a good indication that the ignition timing needs to be retarded to give best power. I subtracted 3° off the figures in the upper 85deg row and got better performance in most rpm areas. One reason might be the fact that better charge of the combustion chamber (caused by exhaust changes p.ex.) burns better and thus can work with less ignition advance. It would be worth to investigate in this area.

Alex There are resonances at a certain rpm level that make the tensioner work most. Where this occurs depends on the whole valve train of the engine. A cali 2 with P3 cam rattled most at approx. 3000 rpm. A Stucchi tensioner together with a new chain works better and is my recommendation for your engine rebuild. New valves of superior quality and guides into both heads are a must. Skim off 1 mm from the heads to eliminate the chamfer in the combustion chamber. Shorten the cylinder barrels to bring the pistons on top of the cylinders. Pay attention to the head gasket: 1.2 mm is the correct thickness, there are also thicker ones available. After all this work is done, the valve clearence to the pistons has to be checked. If the clearence is below 2mm, either the valves have to be set deeper in the seat or the pockets in the pistons must be machined deeper. CR should be around 10,5:1 after this rework and the squish area is optimized. Knocking should occur less than before inspite the higher CR. A new set of rings for the pistons (if you do not replace both) would be a good idea at that mileage. New bearings for the rods big and small ends too. Weigh the pistons to balance them, especially if you repace only one. With all this effort gone into it the engine should be capable for the next 100 000 kms.

Here is an excerpt of my power- and A/F measurements and how they influence each other: I will start with the WOT A/F measurement of my stock 2000 V11 http://www.v11lemans.com/forums/index.php?...ost&id=3746 at 3000 the mixture is extremely lean, this is where the engine tended to ping. at 4000 A/F is at 13:1 what is near the optimum. Here is what the remapping can do for power: http://www.v11lemans.com/forums/index.php?...ost&id=6112 The bike was equipped with Stucchi X-over and my modified stock mufflers on all 3 runs. green is with the stock mapping in the Weber Marelli computer red is with first modifications doing Lambda-measurements on the road and modifying the fuel map accordingly - a little scary driving approx.180 km/h in 4th gear at max rpm on public roads blue is the result of further measurements and modifications on the dyno further gains were made by reducing the spark advance for 3° (off the figures dlaing posted above): http://www.v11lemans.com/forums/index.php?...ost&id=6113 And here is how the remapping changed the A/F ratio: orange is the stock measurement like above left cyl. green is the left cyl. magenta ist the right cyl after the remapping that corresponds to the last power graph Although there was a lot of power found in midrange to top, the torque flatspot is still present. The A/F figures need to be refined on both cylinders and the spark advance may be reduced to a further extent which may will lead to further gains, but I am sure the flat spot will still be there. That leads me to the conclusion that the flat spot is not caused by the mixture. But by what else? Ram effects could be the answer. Different exhaust systems can influence the flat spot as David states above. Maybe the valves and ports are too big and not efficient enough. The cam may has too much overlap and opening time. This is backed up by the fact the power curve does not drop significantly after peak power. An undervalved engine looses power very rapidly after the max power is reached. A lot of work undone on these engines. Ryland The remapping was done by the use of the Ultimap software that allows changes on the fuel and spark maps. At 2700 p.ex. the change in fuel was +50% to get rid of the lean condition at 3000 rpm. You have to consider the lean condition gets worse when an open exhaust is added to the stock mapped bike! Can get dangerous for th engine.

The 4k flat spot is not influenced by the richness/weakness of the mixture. I rectified the mixture and got better torque everywhere but the flat spot basically remained. Remapping or a PC is the only way to adress mixture changes. The TPS is a measuring device, not for mixture tuning. Changing the calibration of the TPS changes the adresses in the map over a large area. This can cause a lot of unwanted side effects.

Al Your rims are 3.5 and 4.5 Rim size is measured on the inside of the rim where the tire sits. If the original paint on the rims is bright silver grey, they are 4.5 rear. 5.5 were all dark grey/anthrazit. On a 4.5 rim a 160/60 tire is recommended, larger tires make the vehicle unstable at higher speeds.

Greg I enter this thread late and did not read all the stuff about K&N vs paper elements because I think it does not matter for any V11. Let me explain this. My first LM2 that I own for 24 years had open inlet. Engine wear (cast liners) was slightly noticeble after 80 000 kms when I first serviced the engine. But the engine would have worked much longer without replacement of the pistons and barrels. Nigusil barrels last even longer. After servicing the engine I equipped it with K&Ns on every carb and I think this is much more protection for the engine than before. After further 60 000 km there was no visible wear on pistons and barrels. They all show the signs of the original machining. Paper elements may filter better, but are worse in rain and and flow slightly less. Engine protection is sufficient with the K&N filter at my opinion. Your above mentioned measurements more relate to the differences in the airbox design than to the flow characters of the filter elements. Ram effects will cause most of the differences. Next I will refer to a recent thread of mine that relates to intake flow and shows the real bottleneck of the engine: flow bench When I was on the dyno with my V11 I compared the open top airbox with the standard one and noticed nothing! Neither went the engine lean with the open box nor was any noticeable power difference measurable. I also compared my slightly modified stock exhaust cans with absolutely open leovinci items. The power difference was unnoticible again and the A/F ratio in the relevant max hp area was similar. In the lower rpms the differences were bigger due to different ram effects by design. See the following graph: The two Leovinci measurements were with open top airbox and stock airbox, don't remember which one is what because the difference is small. The other measurements relate to my modified stock cans, the green one slightly more open. The shape is the same. Above 6000 rpm where the flow is really needed, the difference in A/F is very small if not below the measuring tolerances. The mapping is not stock but the same for all measurements . The conclusion: Powerwise the airbox and filter have almost no influence on an unmodified engine as the airflow is restricted in the intake port near the valve. The discussion bettween K&N and paper element is somewhat religious, not technically based. Both work well when applicated correctly. Just my

The current for the tach has to pass the starter relay and the light relay. I would check these first when the tach fails. When the head lamp and the idiot lights work while the tach fails, it is supposedly not caused by the relays.