Been Around the Block
For your high-speed run ONLY, I'd go with the narrowest tires that can go on those rims. Both for rolling resistance, wind resistance and weight. Tires are pretty heavy so that's an opportunity to trim some KGs, right?
Hehe maybe not. But I will for sure be 'over inflating' them for less rolling resistance"For your high-speed run ONLY, I'd go with the narrowest tires that can go on those rims. Both for rolling resistance, wind resistance and weight. Tires are pretty heavy so that's an opportunity to trim some KGs, right?"
... and you could inflate them with helium!
Thanks for your response savor. Tubeless would help for sure help. And composite parts everywhere. Many stock items made from steel have been swapped out for aluminium and that has saved weight but carbon would be the next step. You are right, the silencer is not light so that could be swapped out for something else. I am still thinking of design considerations though too, so I am not sure how much a sport bike silencer or carbon parts would suit the bike.10kg is a long way to go, that's for sure. Composite fenders would help. The kick starter, kick stand, sub frame, and tank could all be replaced with light weight units. That might get it close. Tubeless would help, maybe. A composite headlight bucket would help, as would composite ears. Maybe a plastic lens if it is glass. Those chrome pipes can't be light.
Also, bathroom scales rely on human feet being there, they usually have two load cells, one for each foot. So when you load the scale in the middle they don't always work well. We went through this in our karting days before we were willing to pony up for proper scales. You can use a piece of wood that bridges two runners to simulate feet and that helps keep the scales more reliable.
My RD350 is like 120kg without fuel. I will lose a few pounds when I go to the new ignition. So maybe 119kg. Without building a bespoke frame or going nuts on high end wheels and a new tank I don't see how it could get much lighter. Maybe 115kg in street trim, that's going pretty bonkers for a bike that gets ridden a 1000 miles a year.
Looks good! Dumb question.... can a person bypass the vacuum switch on an original petcock by using the "prime" position, or do I need to go shopping for manual petcocks?And here are a couple of shots of the vacuum line delete to run the non vacuum petcock. Plus the labyrinth fuel line system I have. It has a quick connect adapter which I love - because that tank comes off quite often to work on the bike, and a 90 degree fuel filter, plus some tubing support springs. I could probably come up with a better looking solution but I like that it is practical and displays that.
Thanks John Awesome you have been land speed racing. It was a dream of mine to get to an event at Lake Gairdner while I was living in Melbourne but I never got there! What class are you the record holder in?I'm really enjoying this thread - lightweight, skinny bikes have always appealed to me. I've been land speed racing at Lake Gairdner (Australia) for the last few years - class record holder - and suspect you'll have no trouble cracking the ton. I think you'll need more than a half mile runway though; you need room to slow down. Light weight isn't an advantage in speed work provided you have room to accelerate; more weight helps with traction on salt and also with stability in crosswinds. Many LSR racers add ballast for these reasons. Drag is the most critical factor and always trumps weight, though there isn't a lot you can do with a naked bike without spoiling its looks. But if you find yourself just a couple of mph short try a 'Busa style front fender that covers as much of the front wheel as possible. Wheels - especially spoked wheels - contribute a large proportion of the drag. Anyhow, it's a lovely bike and I love what you've done with it.
Thanks John Awesome you have been land speed racing. It was a dream of mine to get to an event at Lake Gairdner while I was living in Melbourne but I never got there! What class are you the record holder in?
All good advice, I think if I was so intent on having a road going bike I could do a lot more!
Yes you can do that. The only problem is, if the petcocks membranes have failed, there is no real way to turn off the fuel delivery. Then you really have to hope that the float bowl valve is sealing well and not leaking fuel into the carb throat and then into the engineLooks good! Dumb question.... can a person bypass the vacuum switch on an original petcock by using the "prime" position, or do I need to go shopping for manual petcocks?