Tached1300
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I can’t wait to see the finished product
10-Year Anniversary Freshen-up
- Thread starter fallenarch
- Start date
michael parris heuberger
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Hi. It is my LSR/drag/show/street bike. This is my last build. REMBER THERE IS A LAST TIME FOR EVERTHING.
Tached1300
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Well it sounds like you have saved the best for last or plan to go out with a bang
Nice ride today even though it was cold at 50 degrees, but adrenaline being the great anesthetizer, allowed me to ignore the bite in the air. Today was the first day I have had the bike in more or less finished condition, so she was really ready for me to flog her good. I also have most of the new parts adjusted and the suspension was re-setup based on the new weight. I didn't think about it but loosing 80 pounds is a big deal in terms of suspension setup.
It's hard to tell what is resulting in the amazing handling of this modified bike. If you ask me if big dollars in titanium axles make a difference I can't really say. What I can say is the sum of these parts has added up to a significantly better bike. With Ohlins, the Busa is a pretty capable, if slow handler. I never saw this as a negative, the rock solid stability of the Busa is actually a real advantage riding the back roads at speed. I was worried the bike being twitchy with the Coremoto wheels - it's not. There is just a lot less resistance to turning even laid over at 70+ mph. I always tell people the Busa requires a disciplined line, as changing lines in the middle of a curve increases in difficulty with speed. This bike can now "ride the lines inside the lines" impressively. It's not as agile as a today's crop of sportbikes, but the roads I have been riding for 15 years look absolutely huge in the saddle of this new bike.
Pretty happy and amazed. Not only do I have a bike that has exceeded my expectations, I learned a ton about Busas and motorcycles in general.
It's hard to tell what is resulting in the amazing handling of this modified bike. If you ask me if big dollars in titanium axles make a difference I can't really say. What I can say is the sum of these parts has added up to a significantly better bike. With Ohlins, the Busa is a pretty capable, if slow handler. I never saw this as a negative, the rock solid stability of the Busa is actually a real advantage riding the back roads at speed. I was worried the bike being twitchy with the Coremoto wheels - it's not. There is just a lot less resistance to turning even laid over at 70+ mph. I always tell people the Busa requires a disciplined line, as changing lines in the middle of a curve increases in difficulty with speed. This bike can now "ride the lines inside the lines" impressively. It's not as agile as a today's crop of sportbikes, but the roads I have been riding for 15 years look absolutely huge in the saddle of this new bike.
Pretty happy and amazed. Not only do I have a bike that has exceeded my expectations, I learned a ton about Busas and motorcycles in general.
I want one a those
Dopey
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Careful what ya wish for, mine would do the same for me but expects twice as much in return
. And in case she's looking over my shoulder she knows I'm totally joking and that I'm very lucky ti have her and so is Willie cause I know quite a few that would never do anything of that nature.
Mr Brown
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That's the most expensive mod he's got, and they can be incredibly difficult to get set up. The key is to make sure you get the right one...
No success for me yet.
This is pretty cool. If you have the latest windows you have this video maker. Just add photos and pick a soundtrack and it makes a video for you.
Video is pretty neat.
The bike looks stunning as usual. Lots of hard work for you but it has all paid off by giving you a bike many could only wish for.
That's cool Arch. Beautiful bike. My favorite part was the stogie. What do you smoke?
I have been amazed at the transformation of the bike just from the weight. I think our weight loss leaders @c10 and @ROADTOAD1340 are definitely onto something. Org Service Announcement: Now this is where this will become a long, rambling Willie post, so you can get off here if you like and just take away that less weight is better.
I still believe however all weight loss is not the same. If you recall, the modern age of the sport bikes has been defined by electronics, but just before that was the race for mass centralization. Getting weight close to the center of gravity reduces it's impact on the dynamics of the bike dramatically. But what's more interesting is there is an X and a Y axis running through the CG and where the weight is on these axis is important. Of course there is a z axis too, but that axis has more to do with the bike wheeling. This diagram shows the axes:
I'm guessing where the bike's CG is, but it's close enough for this discussion. To turn the bike is rotating around the X axis, or more precisely it translates around the X axis. Weight above the X axis is going to impact the lean of the bike more as it moves higher above the X Axis. Weight below the X axis is going to tend to impact the bike's willingness to lean less. Bikes aren't like airplanes and they don't exactly rotate around the CG. The fulcrum for the lean is the contact patch of the tires, Still weight below the X axis has less impact so the huge stock cans maybe don't slow the roll rate of the bike so much after all.
Note also that the wheels, axles, suspension are all very close to the X axis and should not impact the roll rate of the bike much at all when lighter parts are subsitituted. But a motorcycle is a very complex physical ballet of forces and reactions. The wheels impact is mostly in the gyroscopic effect that makes it harder to turn them around the axle, and left or right. Weight increases the gyro effect, so lighter wheels have a big impact even though their location is close to the X axis. They also require less HP to turn, so that is an additional benefit.
Aside from the gyroscopic effect of the engine spinning, the other major impact of weight is unsprung weight. That's weight that is not supported by the suspension springs. It includes wheels, bottom half of the forks, brakes, etc. When the bike hits a bump it accelerates upward and the heavier the unsprung parts are the more difficult it is for the suspension to stop the upward movement (compression) and then push the wheels back to the ground (rebound). This was also a surprise for me because the bike feels much more settled since the shop readjusted the suspension for the new parts.
So most of this is probably general information most of you already know. But I sort of went through this analysis after realizing my upgraded Busa is more of a top heavy biased bike. It's pretty subtle, but you can feel it, especially at slow speeds. After giving it some thought, most of my weight reduction came from at or below the X axis. In effect I have raised the bikes CG by changing the ratio of the amount of weight above the X axis to the amount below it.
I'm not complaining, the road speed+ handling of the bike is now pretty amazing. With the old bike, the bike would do what you wanted it to do, but you sort of had to plan the turn just right at higher speeds or things could get a bit hairy. Now, it seems the bike is willing to change lines even when you have committed to the apex. This makes you feel like superman, almost like a sport bike. I am however thinking about what I would get if I lightened the top of the bike. There are limited options here, maybe a lighter seat, Aluminum tank and/or lighter triple clamps.
I think the more I modify the Busa the more I realize what an amazingly well engineered bike it really is.
I still believe however all weight loss is not the same. If you recall, the modern age of the sport bikes has been defined by electronics, but just before that was the race for mass centralization. Getting weight close to the center of gravity reduces it's impact on the dynamics of the bike dramatically. But what's more interesting is there is an X and a Y axis running through the CG and where the weight is on these axis is important. Of course there is a z axis too, but that axis has more to do with the bike wheeling. This diagram shows the axes:
I'm guessing where the bike's CG is, but it's close enough for this discussion. To turn the bike is rotating around the X axis, or more precisely it translates around the X axis. Weight above the X axis is going to impact the lean of the bike more as it moves higher above the X Axis. Weight below the X axis is going to tend to impact the bike's willingness to lean less. Bikes aren't like airplanes and they don't exactly rotate around the CG. The fulcrum for the lean is the contact patch of the tires, Still weight below the X axis has less impact so the huge stock cans maybe don't slow the roll rate of the bike so much after all.
Note also that the wheels, axles, suspension are all very close to the X axis and should not impact the roll rate of the bike much at all when lighter parts are subsitituted. But a motorcycle is a very complex physical ballet of forces and reactions. The wheels impact is mostly in the gyroscopic effect that makes it harder to turn them around the axle, and left or right. Weight increases the gyro effect, so lighter wheels have a big impact even though their location is close to the X axis. They also require less HP to turn, so that is an additional benefit.
Aside from the gyroscopic effect of the engine spinning, the other major impact of weight is unsprung weight. That's weight that is not supported by the suspension springs. It includes wheels, bottom half of the forks, brakes, etc. When the bike hits a bump it accelerates upward and the heavier the unsprung parts are the more difficult it is for the suspension to stop the upward movement (compression) and then push the wheels back to the ground (rebound). This was also a surprise for me because the bike feels much more settled since the shop readjusted the suspension for the new parts.
So most of this is probably general information most of you already know. But I sort of went through this analysis after realizing my upgraded Busa is more of a top heavy biased bike. It's pretty subtle, but you can feel it, especially at slow speeds. After giving it some thought, most of my weight reduction came from at or below the X axis. In effect I have raised the bikes CG by changing the ratio of the amount of weight above the X axis to the amount below it.
I'm not complaining, the road speed+ handling of the bike is now pretty amazing. With the old bike, the bike would do what you wanted it to do, but you sort of had to plan the turn just right at higher speeds or things could get a bit hairy. Now, it seems the bike is willing to change lines even when you have committed to the apex. This makes you feel like superman, almost like a sport bike. I am however thinking about what I would get if I lightened the top of the bike. There are limited options here, maybe a lighter seat, Aluminum tank and/or lighter triple clamps.
I think the more I modify the Busa the more I realize what an amazingly well engineered bike it really is.
c10
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Willie a note about my bird RJ is much weight was removed from above the X axis . Example the ABM / LSL top clamp , and bars are 4 lb lighter than OEM top clamps / solid bars . This is not counting the 1 lb bar end weights . Pair system , mirrors , fuel cap , Shori battery , Penske shock ( remote res not present ) are all above the X axis . Along with a great deal of Ti hardware .
How would you propose we find the exact CG ?
How would you propose we find the exact CG ?
That is what I'm talking about , with late corner entry and mid corner adjustments , my suspension and BST combo , is pretty amazing , getting close to a full sports bike for a fat ish + long wheelbase .
I forgot my battery, that will help some but it's not doing much on my work bench! Don't know on the CF. You can probably estimate it when you lift RJ to weigh it, at least the X axis part of it. I'm pretty sure the Y axis is somewhere in the motor or just above it. Remember a top heavy bias is not wrong. It will increase the bike roll rate and you'll have to watch things putting around the driveway. But if you like that, it is as good as anything else. I am thinking a low CG is more stable and a high CF is quicker turn in.
I guess mine has a bit done as well , the top clamp and clipons weigh 1kg total , also carbon panels no inner foam on them , super light stock seat , the Shorai is a lot lighter than original Yuasa , but nearly double what is out there that could replace it . The aluminum subframe is 3kg + lighter , and tank mount is lightened out .
@Dai. has gone further with his Yoshi tank and HP upgrades , he has most if not all chassis mods as my thing has had done , but is already to go further , perhaps even with his other Gen 2 build , he is really onto it , and more one eyed Busa than most !!
@Dai. has gone further with his Yoshi tank and HP upgrades , he has most if not all chassis mods as my thing has had done , but is already to go further , perhaps even with his other Gen 2 build , he is really onto it , and more one eyed Busa than most !!
I can only imagine! If I'm being honest since I have been really putting the Busa through it's paces I wonder each ride if the BSTs were not the ticket. The new sport bikes are getting longer to help with the power they have these days. The RSV1100RR has a 56 inch WB and the Busa was listed as 58 inches.
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