Paul Minnaert Posted February 22, 2003 Share Posted February 22, 2003 Because I'm busy with my bike, and it's in pieces now, I decided to extend the swingarm some 6 cm, and move it's rotating point 7 cm forward. Extension will be to the front. The V11 gearbox made this posible, so why not take advantage of it? This week the swingarm gets extended, if all goes well. Then I have to make new aluminium plates for the frame, new footpegs/brake/gearlever. And the crosssection pipes that make the region there stiff. In 5-6 weeks the bike has to run again, because of a track day. I you posted. Link to comment Share on other sites More sharing options...
dlaing Posted February 23, 2003 Share Posted February 23, 2003 Great Idea! So do you also have to make the drive shaft 13cm longer? I would love to move the rotating point as far forward as possible and then move the rear wheel back a few centimeters to move more weight over the front wheel. Yes, it would not handle as quickly but the trade off in weight balance would offset that value, and the added length would make it a better touring bike. Heck, I'd even give up the paralever effect to make a longer swing arm. Perhaps a Quota swing arm would be just right. I am pretty sure your goal is to make it a better sport bike, so your modifications make sense. I hope you get it done in time! Link to comment Share on other sites More sharing options...
Paul Minnaert Posted February 23, 2003 Author Share Posted February 23, 2003 the drive shaft stays the same lenght. the wheelbase is shortened 1cm. But in this setup the lenght of the driveshaft only differs 1mm between max and minimum height. Thats diffent than standard! because the centers are on the same place. Guzzi should have done it. But that's always with guzzi, they leave something to do yourself. Or make mistakes, as extending the wheelbase as with the le mans 2001, because the setup on the 2000 v11 was wrong. My wheelbase will be some 1450 mm that's 1475 now, -10mm for the swingarm, and -15 because I have WP forks with 30mm offset, instead of the 45 from the marzzochi Link to comment Share on other sites More sharing options...
Mike Stewart Posted February 23, 2003 Share Posted February 23, 2003 I see that Ghezzi and Brian also makes head bearings that steepen the fork rake 1 degree. This will shorten the wheel base a hair and make the bike steer quicker at the same time. Who wants to try it out first? The V11 does need a longer swingarm, just a cm. will make a large difference. Take pictures along the way so we can see the progress. The rear shock might have to be revalved and resprong to work with the added leverage of the swingarm. Mike Link to comment Share on other sites More sharing options...
Paul Minnaert Posted February 23, 2003 Author Share Posted February 23, 2003 I see that Ghezzi and Brian also makes head bearings that steepen the fork rake 1 degree. This will shorten the wheel base a hair and make the bike steer quicker at the same time. Who wants to try it out first? The V11 does need a longer swingarm, just a cm. will make a large difference. Take pictures along the way so we can see the progress. The rear shock might have to be revalved and resprong to work with the added leverage of the swingarm. Well I have these bearings since 7 years. The rearshock is a White Power unit, that's now at the wp workshop to get a revision, they will extend it for 5mm. The aim is to lift the back a bit. The front is going to drop 30mm because I also have WP forks that are 30 mm shorter. The shock has a 2:1 ratio with swingarm travel. So 12 cm rearwheel travel gives 6cm shock extension. That gives extending the shock 5mm stets the back 10mm higher. Link to comment Share on other sites More sharing options...
al_roethlisberger Posted February 23, 2003 Share Posted February 23, 2003 Help me out here guys... ...why would a longer swingarm(while keeping essentially the same wheelbase) make any real difference on these bikes? It's not that I doubt you, but I'm just ignorant in this area. thx! al Link to comment Share on other sites More sharing options...
Paul Minnaert Posted February 23, 2003 Author Share Posted February 23, 2003 they say "size doesn't matter"? You see all sports bikes doing there very best to make a long swingarm, started with the R1. The swingarm angle between min and max height is smaller with a longer swingarm. In our case, from 40cm > 47cm this goes from 17 degrees to 15 degrees with the 12cm wheeltravel. Link to comment Share on other sites More sharing options...
Mike Stewart Posted February 23, 2003 Share Posted February 23, 2003 Well Paul, looks like you did your homework! Keep us posted on how the project is comming along. Mike Link to comment Share on other sites More sharing options...
dlaing Posted February 24, 2003 Share Posted February 24, 2003 From what I understand, the main benefit is less torque reaction, resulting in less jacking while accellerating and decellerating. On a shaft drive it can mean less wear on the shaft....if they get the geometry right... I wonder how the V11 six speed's shaft and swingarm compare with the earlier Sports and Daytonas. Link to comment Share on other sites More sharing options...
Paul Minnaert Posted February 24, 2003 Author Share Posted February 24, 2003 I wonder how the V11 six speed's shaft and swingarm compare with the earlier Sports and Daytonas. the swing arm is the same lenght, as are the mounting points, the shaft is somewhat longer because the box is shorter. And the shaft comes 15 mm lower out of the gearbox. Because of that, the swingarm has a big oval hole in it. But regarding to the frame, very little changed from the sport 1100I to the first v11. The le mans and later have an extension just behind the steering head. and the front enginge mount. And the bars between gearbox and swingarm mounts are strengtend. Link to comment Share on other sites More sharing options...
Paul Minnaert Posted March 1, 2003 Author Share Posted March 1, 2003 Here to see that the swingarm is extended. Not yet compete ready. Link to comment Share on other sites More sharing options...
Dirtybill Posted March 8, 2003 Share Posted March 8, 2003 The reason bikes like the R1 used a longer swing arm was to keep the front wheel from getting airborne on acceleration. Not really a serious problem on a Guzzi. It also helped to line up the countershaft sprocket in a direct plane with the swing arm. And aren't you defeating the purpose of the paralever if you lengthen the swing arm and disconnect the paralever? And if I understand this correctly, you'll be altering the angle of the drive shaft? How do you know you have an angle that won't cause excessive wear on the joints? Link to comment Share on other sites More sharing options...
Paul Minnaert Posted March 8, 2003 Author Share Posted March 8, 2003 And aren't you defeating the purpose of the paralever if you lengthen the swing arm and disconnect the paralever? And if I understand this correctly, you'll be altering the angle of the drive shaft? How do you know you have an angle that won't cause excessive wear on the joints? I don't disconnect the paralever. The angle the driveshaft makes will be less than original, the less angle the better. The lenght of the paralever is important to have the angle on both joints the same. Guzzi didn't change the pivot point for the swingarm when mounting the 6 speed bx. But the point where the shaft is comming out of the box is 15mm down, and 60 mm up front. So what I do, is bringing both pivot points in the same palce again. The max angle the swingarm ( and shaft) makes is smaller, because the arm is longer. And the further you go from the center the worse it gets for the joints. Link to comment Share on other sites More sharing options...
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