Lucky Phil

The OP put up a photo of a 2 into 1 exhaust system for his ROAD bike and my comments still stand. You can guarantee 99% that the pictured setup bolted on will have less performance than the stock setup and 100% guarantee it will be obnoxiously loud. The only solution then in keeping the muffler the same, is that you do some DB killer mod and then you can still guarantee that it will be loud and performance will once again be worse than stock. The only way to keep a road bike legal/quiet is to have the the muffler volume to attenuate the sound. Different configurations of the same capacity require different muffler solutions in detail. This thread has now gone down the path of race bikes and their requirements which, although the basics are broadly the same don't have the same considerations with regard to attenuation. IE they can be louder. So my factory Ducati TT2 from the early 80's had a 2 into 1 reverse cone megaphone without baffles as did the same bike we used at the IOM in 86. There were NO noise restrictions at the time that we had a problem with. As for the anecdotes about the performance of your bike and how loud it is ...well, we could all go on forever without empirical evidence but the fact remains the OP system shown simply doesn't have the required muffler volume to support a performance increase and a decent/legal level of sound attenuation and any attempt to keep the same appearance and quieten it down will fail on either count and almost certainly both. As for the advantages of attenuating a twin over any other design of the same capacity, well the advantage you mention is overwhelmed by the fact that for a given capacity the twin creates a gas pulse of twice the volume for the system to deal with and at a lower frequency. The lower frequency is much harder to deal with than what an inline 4 produces and I think its quite well know that a twin for the same capacity is more difficult to attenuate than a 4. Look at the muffler volume required on say a WSB1198 compared to a Honda at the time.The Ducati required much greater muffler volume ( whether it was twin can or the 999 box) to stay within the noise requirements. My V11 has to date had 5 different muffler configurations and 2 crossover. The only performance difference was with the new crossover which improved the mid range hole. The different mufflers are purely a personal preference but all gave similar levels attenuation but quite different sounds. Ciao

What? Guzzi sells plenty of big twins with two into one ppipes stock. So do other brands like Aprilia, Suzuki, Honda, Yamaha, etc.. The main reason for two into two exhausts is looks.Being a two into one system does not automatically make it louder than a two into two. It can be louder, but it can be quieter. My Griso with the stock two into two into one pipe is as quiet as the wifes V11 with the stock pipe. My Griso with the two into one aftermarket pipe and the db killer I put in is quieter than either the wifes V11 or my Daytona, both with aftermarket two into two set ups. You may find that with a large open muffler it is too loud, but you could also restrict that large open baffle with a DB killer if required to quiet it down. It comes down to tastes. Correct answer.....Unless you want a pig ugly exhaust and muffler system then to get the performance and keep the sound legal you need a 2 into 2. The Griso is a good example of what I'm talking about,ugly as sin, and although I haven't been inside one its debatable whether its a single muffler or a siamesed unit, what with its twin outlets and all.Wont even bother with the Suzuki twin range and their attractive twin cylinder range muffler....not. You simply cant keep the noise reasonable and the performance good with a muffler as pictured in the original post. Ducati tried the single muffler design with their 999 years ago and to get the performance they had to resort to an ugly box. Do you really think that simply adding a DB killer to your single aftermarket muffler doesn't destroy any perceived performance gains you may or may not have got? If it was that easy we wouldn't have the giant ugly boxes we all have to put up with stock. Ciao

Does that shifter shaft extension have an outrigger/support bearing? Ciao

Performance will suffer and noise will be obnoxious OR performance will REALLY suffer and noise will be high.Take your pick. There's a reason large capacity twins generally have twin mufflers. See if you can guess why. Ciao

McDonalds is the answer, start "supersizing" and sag increases, stick to the junior burger and in decreases. Its all very straight forward. Ciao

From what I gather, the OEM oil pressure sender unit is not highly reliable. A basic mechanical gauge can be installed for not much more cost than a new sender. Then you will also know how much pressure you have under various conditions - such as whether the bike is getting oil-starved on hard acceleration or steep inclines. Some people just prefer gauges over warning lights - because gauges give you more warning. @JB - I have an external gauge that you borrow if you just want to test pressure and are not concerned about a full-time reading. Well I guess you may as well fit a Voltmeter, oil temp, and cylinder head temp gauges while your at it. Just to be sure to be sure. The one shown fitted in the photos above has to be in the silliest place ever. If your going to waste your time fitting one you may as well have it in a location where you don't have to look at your knees to read it. As for the reliability of the std switch well you can just replace it every 5 years or so and cover that if its such a worry. What is it with Guzzi riders and gauges.Oil pressure,oil temp, voltmeters.....where will it end. Ciao

Why in the world would you want to run an OPG? Ciao

Doing the rear brake pads on the V11 is easy thankfully. These Brembos are pretty nice to work on. Small though. I am amazed how they threw on such a small caliper on a 550lbs bike. Can't wait to get my Scura with the 4 piston caliper from a V11 Jackal. Should of had a 4 piston from the start. Who the hell uses the rear brake for slowing or stopping on a sports bike anyway. A four piston caliper would be a ridiculous overkill. Ciao

Just a small hammer. I only get it out so the Guzzi knows I'm serious and not to mess me about. Ciao

I'm 6'2'' with long legs and why anyone would want to fit lowered pegs (or worse still further forward) is beyond me. Here is my peg solution ( Ducati 1000ss pillion pegs off ebay) Ciao

So $294 and he didn't spend 5 min painting the needle while he had it apart because he wasn't told to!!! He wouldn't get my recommendation. Ciao

No the Guzzi system is flawed in that the regulator senses voltage off the light circuit and when the lights are turned on there is a voltage drop in the circuit that isn't reflected at the battery. The reg then thinks battery voltage is low and overcharges the battery. Lower draw LED's would minimize the effect but the solution is to either wire the headlight circuit or the reg directly off the battery. I went the former and included some relays in the system to remove the load from the handle bar switch assy. The problem with the reg wired directly from the battery is that its always "live" and will drain the battery over time. Ciao

Never fails to amaze me how easily people are impressed. Ciao

Wrong on both counts, perfectly adequate test using air, crack pressure is crack pressure at 60psi oil or air doesnt matter. If you were interested in the flow rate after it cracked then it would. No its a straight piston and spring,pump pressure one side crankcase pressure the other,so for all intents and purposes its spring preload that determines the crack pressure Ciao

Pressure information without RPM info is a little bit pointless. Ciao

Actually Roy there are 3 springs in the V11 shifter system if you include the detenting spring. For anyone interested I posted a writeup and pictures at wildguzzi on massaging the V11 shifter system. Here's the link. http://wildguzzi.com/forum/index.php?topic=80481.msg1268500#msg1268500 Ciao

Well, who's to say that the std pump isnt a "high flow" unit and although slightly smaller the aftermarket unit is also "high flow". The limiting factor for the flow rate of the std pump might be the restrictive inlet or delivery ports and the aftermarket unit addresses this. There is more than the size of the gears involved. It doesnt say "HIGHER flow" Just saying. Ciao

The oil pressure relief valve is there primarily to protect the system in cold weather starts. If its not present the oil pressure can go over 120psi and do things like pop the filter seal (Ducatis known for it occasionally even with the valve) and rupture the oil cooler if fitted. During normal operation with engine oil up to temp the OP valve will generally be closed even at high revs. So if you add hydraulic lifters and or oil squirtes for the pistons etc you will often need a larger capacity pump to maintain the same OP or as I said drive it faster by a ratio change. There are a lot of design variables here and the limiting factor can be oil pump inlet and or delivery size etc. The common mistake is to value pressure over flow. Ciao

Thanks for the info Roy. Ciao

Cant say, I hardly ever ride at night and when I do its always city/suburban stuff. Ciao

Ok so I ran a seperate fused hot wire to the headlight and a return earthed to the engine block along with the regulator earth as suggested by Kiwi-Roy. Made the reg earth to engine block heavy cable. All fitted up quite nicely so now the headlight switch is only low amperage relay control. Happy to say the headlight circuit voltage is now very stable with only 0.04V drop from battery to the reg sensing point with the headlights on or off and a maximum regulator output of 14.1 Volts with the original reg. Should be kinder to the battery. Thanks to all that helped. Ciao

If it runs well in at various tempriture and riding conditions then leave the std ECU in place. Ciao

There are some things that just require manning up and one of those is how you look when you mount the bike and pull away, especially from the pub. You need to suck it up on those occasions and look totally at ease. Again cycling nicks under the jeans/pants.....descrete and no sore ass. Ciao

Well I'll put your experiences in the "under review" file for future decisions. You may well be right and technology moves forward usually. Ciao

Manky for me just means horrible looking....probably wrong but there you go. The advantage of the cycling nicks is they give you padding and absorb sweat and dont ruin the look of the bike. I mean who wants to park up and enjoy a nice Coffee while looking at some revolting looking piece of furry skin draped across the seat totally ruining the look of the bike. Makes you look soft as well to all the non riders and will scare small children. Dont even go there. Ciao