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Showing content with the highest reputation on 06/29/2020 in all areas

  1. Is there any other way that you could photoshop, so badly, such a cornucopia of ugliness? It really is praiseworthy for that, and only that......
    6 points
  2. What realy excites me is to ride my bike 'on the cam'. And that applies to any bike at all. Its just that you cannot ride anything modern and powerfull in such way if you want to be back home for your supper and not ending in a box or in jail. I have a few small bikes like an Airone Sport or a Bultaco 350 and enjoy them immensely when i can wring them around coaxing every horse availlable to stay 'in the zone' and on song. May be i am old fashioned and missing something but the Airone at 60mph is more fun than my ex Stelvio at 130. Many customers aren't looking for silly power and over prepped steers, technology is a lure and progress an illusion, give me two valves and pushrods please. There wont be any need to rebuild the head at silly expense or to remortgage your house to reshim your desmo. So for me, guzzi is on the right track staying air cooled and pushrod , keeping production costs down , but with the added value of a shaft drive thus reducing maintenance. As a mechanic, i cannot but admire the skills of the creators of those super rockets but it somehow lets me cold.
    2 points
  3. A few thoughts about this. First, many people think that a larger pipe will keep exhaust velocity up, but that is not how it works. If you were to compare two systems, one with a larger pipe diameter than the other but both close to the right size, the larger diameter pipe system would have lower exhaust gas velocity than the smaller pipe diameter system. There is a max size for exhaust pipe given your displacement and power levels. Anything above that slows exhaust gases down. Really trick systems will use a smaller diameter pipe right out the exhaust port and step up to larger diameter pipe 6 or 8 inches down the pipe. They are counting on the fact that the fuel / air mixture is still burning as the exhaust exits and as such it is still expanding. Because of that, the pipe diameter required for best exhaust flow is less right away by the exhaust port and increases further down the pipe as the air / fuel mixture finishes burning. But any sudden increase in pipe diameter / size will result in a slow down of the exhaust gases. Sadly, the stock exhaust crossover is just such a change in diameter / cross section. But the stock system is built to be cheap to manufacturer while working well enough. After market systems should be able to work better. But how much better can vary. Next, exhaust gases do no flow out the exhaust in a steady flow, they are pulses. Between the pulses there are waves of negative pressure that flow back up the pipe. Since the Guzzi V twin doesn't fire the two cylinders at the same time the pulses of exhaust from each cylinder are never trying to flow out the pipe at the same time. If the system works well, the negative pressure waves flowing back up the pipe from one cylinder will help the other cylinders positive pressure exhaust pulse exit quicker, which then can cause a stronger negative pressure wave to arrive at the exhaust port of that cylinder. The interaction between positive exhaust pulses and the negative pressure wave happens both between the two cylinders at the crossover and at the exhaust valve. But because a 90 degree V twin doesn't have an even firing interval between the two cylinders the affects of exhaust negative pressure waves are more likely to be back at the exhaust valve from that same cylinders exhaust pulse. But there are systems with complex crossovers, like the Ducati "spaghetti" system that have two separate crossovers to address the differences in timing between the two cylinders. All I can really say is back in the day I wanted a two into two system for our Ducati 750 twin racebikes (two separate exhaust pipes, basically). I did not think that a two into one system, or a two into one into two system, would work best on a 90 degree V twin. But we ended up having a system built by a guy who built exhaust art. And he didn't build what you told him, he built what he knew would work. We ended up with a two into one system. It maybe did not make the most peak power, that probably would have been from a two into two system, but it made more power under the curve and as such was ultimately faster than other bikes that claimed to make more peak power. Another really cool exhaust technology is merge collectors. If you want to learn more, google that. Merge collectors put a lot of effort into merging the different exhaust pipes into a single pipe while controlling and maintaining the size / cross section the whole way. They don't really have a lot of benefit for a 90 degree V twin like a Guzzi, but they are exhaust art.
    2 points
  4. I suppose everybody's bike is different but I have a 86 LM1V with over 180K miles and been through many tires. Swapped bikes with a bud with his 02 Lemans way back when on a Texas trip and he told me my suspension sucked. I guess after all those miles I had just adjusted to to it. He ordered progressive rear shocks and fork springs for me and it really improved the bike. The best combination I have found for tires afterward is a michelin macadam on the rear and metzeler lasertec 33 on the front. Worst were bridgestone bt45 as had tank slapper scary deals when riding fast over elevation changes.
    2 points
  5. I know,I generally let people who know what they are doing just get on with their work.It was more a precaution because I didn't know that much about their work other than a system with conical headers on the website (It's gone now)for the v11.A good example of why that is a good idea,I think, is why the music industry was so much better in the 70's compared to now.Some guy believed in a band or a singer and just let them create. I'm looking forward to reading about your exhaust for the Aprilia.
    1 point
  6. http://www.moongarage.it/2019/05/27/moto-guzzi-1400-8v-pikes-peak/
    1 point
  7. Hmmmmm . tank slapper . I do not care for them .
    1 point
  8. LC251868436US In transit..
    1 point
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