Jump to content

Recommended Posts

Posted

Watching the Utah race (yes, I'm behind on the DVR) and Greg White says that FIM allows 374 minimum weight for 1000 and 370.5 for Superbike.

 

I looked at the dry weight for my 2006 Fireblade and its 435lbs. How in the world do they take that much equipment off to make it that light? Must be a nice ride at that weight.

Posted

Watching the Utah race (yes, I'm behind on the DVR) and Greg White says that FIM allows 374 minimum weight for 1000 and 370.5 for Superbike.

 

I looked at the dry weight for my 2006 Fireblade and its 435lbs. How in the world do they take that much equipment off to make it that light? Must be a nice ride at that weight.

 

There's a TON of weight on a street bike. Here's a list of areas you could invest in weight savings. With some super rough estimates on weight not based on any specific bike (off the cuff guesstimate). On a bike of that caliber every gram counts.

 

-Lead Acid Battery -5lbs

-Exhaust 5-12lbs

-Bodywork -5-15lbs (headlights and tail lights excluded)

-Fuel tank 10-20lbs (Aluminum or Carbon)

-Fairing Stay 3lbs

-Wheels 10-25lbs

-Subframe 3-5lbs

-Forks 3-5lbs

-Rotors 1-2lbs

-Sprocket 1lb

-Chain 1lb

-Fasteners 1lb

 

Generally as a rule of thumb the higher on the bike the more critical the weight. Weight at the wheels is also quite important. While every gram is important you do reach a point of diminishing returns where the amount of cost often does not justify the replacement of the part for such a small performance gain. Some of the biggest "bang for the buck" for weight savings is in the wheels and the Battery. A free weight savings is how much fuel you put in the bike. If you know exactly the distance it needs to travel and put in that exact amount of fuel and very little more you can save a lot of weight over a full tank. :)

 

I really should go about weighing my track bike sometime. I have BST Carbon wheels as well as carbon race bodywork and most of the weight savings stuff on that list. When I sit on it I gain a lot of that weight back it still would be a fun figure to know. I have managed to stay somewhat sane with it and have only replaced parts that have a meaningful weight savings. Some people however spend tens of thousands of dollars for titanium and other parts without knowing their actual weight savings. I have even known people who replaced aluminum parts with Titanium and thought that saved them weight. Aluminum is lighter than Titanium. Ooops! :)

 

The RR is 458LBS wet from the factory. BMW did a lot of good engineering on the RR and it has the lightest factory cast aluminum wheels in the industry and an aluminum gas tank from the factory. It's amazing the bikes out there running around with steel ones.

Posted

You forgot Titanium Hardware, its very expensive, but there's a lot of weight savings there if you wanna spend the money, especially with things like the axle shafts, the weight difference even in stuff like banjo bolts for the brakes is pretty incredible

 

 

Robert,

 

You can easily weigh your bikes with a bathroom floor scale and a few pieces of plywood or 2x4, and also determine the weight bias of the bike at the same time

Posted

I was shocked at the weight of the front fairing stay (which supports headlight, etc.) on my husband's Ducati when he took it off to replace the front fairings with race fairings.

 

And for sure removing the stock exhaust and catalytic converter on virtually any bike is a huge weight reduction.

Posted

You forgot Titanium Hardware, its very expensive, but there's a lot of weight savings there if you wanna spend the money, especially with things like the axle shafts, the weight difference even in stuff like banjo bolts for the brakes is pretty incredible

 

 

Robert,

 

You can easily weigh your bikes with a bathroom floor scale and a few pieces of plywood or 2x4, and also determine the weight bias of the bike at the same time

 

Hmmm. One wheel at a time? Might have to try that.

 

I did not think of banjo bolts and parts like that. I have done some Titanium on my bike but mostly stuff that is involved with unsprung weight such as caliper bolts and sprocket bolts. Might have to look at others.

 

People also remove parts such as ABS pumps and while I could probably get away with no ABS it's really nice to have that safety net "just in case".

Posted

I was shocked at the weight of the front fairing stay (which supports headlight, etc.) on my husband's Ducati when he took it off to replace the front fairings with race fairings.

 

And for sure removing the stock exhaust and catalytic converter on virtually any bike is a huge weight reduction.

 

What's even more shocking is the weight of factory bodywork as well. The stuff is designed to last and look good for the lifetime of the bike. When I got my CF race bodywork my mechanic joked that the cardboard box and packaging materials weighed more than the parts inside. The crazy thing is it was true. Even the cheapest Fiberglass stuff way lighter than factory stuff.

 

I did a CF fairing stay mostly to be slightly "over the top" but then realized the amazing weight difference. The Factory one weighed a few pounds and the CF one barely weighed anything. That weight is high up on the bike too.

Posted

 

Yes, stack something of equal height as the floor scale, so that the bike remains level, ( if your lucky the height of the wheel on stands will be very close ) weight each wheel with the bike upright and level, combine the values for total weight and then you can use some easy maths to figure your weight bias front and rear.

 

You can also use this technique with super heavy bikes but need to add additional weight distribution on the scale to not over range it, and do a little more math as well

Posted

 

 

Yes, stack something of equal height as the floor scale, so that the bike remains level, ( if your lucky the height of the wheel on stands will be very close ) weight each wheel with the bike upright and level, combine the values for total weight and then you can use some easy maths to figure your weight bias front and rear.

 

You can also use this technique with super heavy bikes but need to add additional weight distribution on the scale to not over range it, and do a little more math as well

 

 

Makes sense. Might have to do this sometime for fun. With most bathroom scales able to measure 300 lbs or so this is not that far fetched.

Posted

RChase you listed forks. Are aftermarket lighter? I changed out the internals on my F4i forks. Forks are heavy but I didn't figure a savings could be had with another brand.

Posted

RChase you listed forks. Are aftermarket lighter? I changed out the internals on my F4i forks. Forks are heavy but I didn't figure a savings could be had with another brand.

 

That really depends on the specific fork and specific bike. On some bikes a set of cartridges are lighter than a full set of forks. There's also different grades of forks. Take everyone's favorite for a moment Ohlins. They have multiple different types of forks you can get for specific bikes. Some of them aren't listed on their more consumer oriented marketing materials.

 

Some of the reasoning behind the different weights of forks is the feature set and the stiffness of the fork tube. Some of them have more components inside the fork and some of the tubes are thicker or thinner for various performance reasons.

 

In order determine what the lightest fork option is you have to first determine what performance and features is the most important for you and then start looking at the specific weights of all of your options. It's a bit time consuming. But if building a high performance bike was easy everyone would be doing it. :)

 

My RR has Ohlins cartridges. The consumer grade Ohlins options are all heavier than the factory BMW fork tubes. BTW Ohlins is not the only game in town. There are lots of other vendors out there making great products that are just as good as Ohlins stuff. Some of it lighter and some of it performs slightly better. This is due to the competition in this market and the willingness of the newcomers to the market to take higher end features found on more race oriented products and push them into the consumer market. They have to do something relevant otherwise all the suspensions would remain gold.

 

It's interesting as well. The Ohlins stuff not listed for mere mortals like you or I to buy is quite expensive. My mechanic who did a lot of AMA racing told me about a bike that he rode that had some of the higher end Ohlins suspension on it. The chief mechanic for his pit crew would often remind him that the suspension was worth way more than the entire bike. OUCH! :)

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...