More extreme weight reduction

[Draco1340]

There have been plenty of posts on typical weight reduction methods for the Gen I and Gen II, and to be honest, getting the first 60 lbs off are easy. Like many of you, my bike is 10% semi-legal street bike, 90% hard core drag bike. I was looking for ideas on the next 50 lbs, getting the bike down to about 450 lbs. Again, all the obvious stuff is done starting with:

A/H pipe with no baffle (and you think the regular A/H is loud!)
all pannel insulation and tank insulation removed
custom chrome moly rear subframe
removal of belly wing and steel bracketry and relocation of regulator
carbon BST wheel (rear only)
PAIR valve and bracketry removal
modified rear disk
custom seat
catalyst tail
integrated rear brake light and elimination of turn signals
1 front rotor and disk removal
​

Now I need to begin with the more difficult mods.

I cut out the frame cross brace that is in back of the steering head
I was thinking of removing the oil cooler. All turbo bikes run without them, right?​

I was thinking of using lithium ion batteries to start the bike. Anyone do this?
Are there other frame modifications that are typically done? Not looking to make a grudge bike, but would like some new ideas on getting down to 450 lbs fueled with N2O tanks on board.

 

[sean06]

There have been plenty of posts on typical weight reduction methods for the Gen I and Gen II, and to be honest, getting the first 60 lbs off are easy. Like many of you, my bike is 10% semi-legal street bike, 90% hard core drag bike. I was looking for ideas on the next 50 lbs, getting the bike down to about 450 lbs. Again, all the obvious stuff is done starting with:

A/H pipe with no baffle (and you think the regular A/H is loud!)
all pannel insulation and tank insulation removed
custom chrome moly rear subframe
removal of belly wing and steel bracketry and relocation of regulator
carbon BST wheel (rear only)
PAIR valve and bracketry removal
modified rear disk
custom seat
catalyst tail
integrated rear brake light and elimination of turn signals
1 front rotor and disk removal
​

Now I need to begin with the more difficult mods.

I cut out the frame cross brace that is in back of the steering head
I was thinking of removing the oil cooler. All turbo bikes run without them, right?​

I was thinking of using lithium ion batteries to start the bike. Anyone do this?
Are there other frame modifications that are typically done? Not looking to make a grudge bike, but would like some new ideas on getting down to 450 lbs fueled with N2O tanks on board.

Im all for weight reduction, but I think your trying to remove it from the wrong palce. I have a buddy that just removed 1 of his front brakes and had a hell of a time keeping the front end down. He actually ended up going slower and he removed over 15lbs from his bike. I would leave all the weight up front that I could. Ive even been thinking of adding some ballast up front down low. Im sure I would go fast with the extra weight.

 

[Draco1340]

Sean, agree with you 100%. That one of the reasons why I only sprung for the BST rear wheel. I'm at +7.5 inches, and not having much of a chassis problem either spinning or lifting, but every time you make a weight change you have to go back and play with wheel base and tire pressure and front end height to get things to work again.
I left off:

Mac +10" chrome moly rear arm (much lighter than stock)
Fuel cell with fiber glass cover (in development right now)
run 45 miles per week ​

 

[bisquit61]

replace as many nuts and bolts as you can with titanium. Expensive but it works.

 

[afterhours]

some thoughts:

1. aftermarket front wheel, or GSXR front end swap
2. swingarm, not sure what you have now.
3. gas tank, and gas cap. replace with lighter airtech or catalyst pieces
4. upper fairing bracket, lightwieght aluminum or just drill out the stock piece
5. ignition, replace with liteweight switch

 

[Got-Busa?]

The fuel tank is probably the next biggest thing but you're already working on that. You can do several other things but it's a matter of cost. For what you are going to spend in lighter parts, you could add more power for the same (or less) money...

Carbon fiber clip-ons, move battery behind headlight, race or carbon fairings, aftermarket rearsets, etc..

Post pics...

 

[bigfootatplay]

I removed the rear brakes,rear pegs, brake fluid resevoir in rear, rear brake arm, lines,caliber and rotor is next and will be cutting the hanger that holds the caliber for another loss.I cut all unnecessary braces from the subframe and the stock exhaust mounts underneath the bike,no oil cooler, Catalyst tail, cut out front headlight, led in rear, no signals, no mirrors, stripped foot pegweights off pegs,no toolkit,drag seat,fiberglass cut tank,gsxr1000 wheels,forks and trees, re-routing batt where headlight would have been,chromoly 74" arm, next I'll be changing subframes..

The GSXR1000 forks are actually 4lbs heavier but weight up front is acceptable and it gets me lower. The wheels are 8lbs lighter. Later on I'll get a catalyst race front(one piece) to take off more... then its time for me to drop some... I'm 300lbs now. Hoping for more like 260lbs then they better watch out.???

 

[afterhours]

I removed the rear brakes,rear pegs, brake fluid resevoir in rear, rear brake arm, lines,caliber and rotor is next and will be cutting the hanger that holds the caliber for another loss.I cut all unnecessary braces from the subframe and the stock exhaust mounts underneath the bike,no oil cooler, Catalyst tail, cut out front headlight, led in rear, no signals, no mirrors, stripped foot pegweights off pegs,no toolkit,drag seat,fiberglass cut tank,gsxr1000 wheels,forks and trees, re-routing batt where headlight would have been,chromoly 74" arm, next I'll be changing subframes..

The GSXR1000 forks are actually 4lbs heavier but weight up front is acceptable and it gets me lower. The wheels are 8lbs lighter. Later on I'll get a catalyst race front(one piece) to take off more... then its time for me to drop some... I'm 300lbs now. Hoping for more like 260lbs then they better watch out.???

you and me both...

 

[sean06]

Sean, agree with you 100%. That one of the reasons why I only sprung for the BST rear wheel. I'm at +7.5 inches, and not having much of a chassis problem either spinning or lifting, but every time you make a weight change you have to go back and play with wheel base and tire pressure and front end height to get things to work again.
I left off:

Mac +10" chrome moly rear arm (much lighter than stock)
Fuel cell with fiber glass cover (in development right now)
run 45 miles per week ​

Oh right on, I didnt know you were running a longer wb Have you thought about a speedcel batt.? I got the big one so I didnt have to ever worry about the batt and it only weights 2lbs! Its expensive, but a big weight savings.

 

[sean06]

I removed the rear brakes,rear pegs, brake fluid resevoir in rear, rear brake arm, lines,caliber and rotor is next and will be cutting the hanger that holds the caliber for another loss.I cut all unnecessary braces from the subframe and the stock exhaust mounts underneath the bike,no oil cooler, Catalyst tail, cut out front headlight, led in rear, no signals, no mirrors, stripped foot pegweights off pegs,no toolkit,drag seat,fiberglass cut tank,gsxr1000 wheels,forks and trees, re-routing batt where headlight would have been,chromoly 74" arm, next I'll be changing subframes..

The GSXR1000 forks are actually 4lbs heavier but weight up front is acceptable and it gets me lower. The wheels are 8lbs lighter. Later on I'll get a catalyst race front(one piece) to take off more... then its time for me to drop some... I'm 300lbs now. Hoping for more like 260lbs then they better watch out.???

How big of a project is the 1k fork swap? I have been interested in this so you can get offset tripples. Offset forks look bad ass on a slammed busa, and it helps get more weight over the front. And you then have shortend the wb, but kept all the benifits of the longer wb. Is this right?

 

[Mr Brown]

How big of a project is the 1k fork swap? I have been interested in this so you can get offset tripples. Offset forks look bad ass on a slammed busa, and it helps get more weight over the front. And you then have shortend the wb, but kept all the benifits of the longer wb. Is this right?

You can get offset triples for the busa. You can have a longer arm with a given wheelbase.

 

[bigfootatplay]

How big of a project is the 1k fork swap? I have been interested in this so you can get offset tripples. Offset forks look bad ass on a slammed busa, and it helps get more weight over the front. And you then have shortend the wb, but kept all the benifits of the longer wb. Is this right?

yep... I'll post pics thru out the change so you guys can see how to do it

 

[sean06]

You can get offset triples for the busa. You can have a longer arm with a given wheelbase.

Do you know who makes this setup? I thought that was the reason why peopel went with the 1k forks so they could get offset tripples. If you can get them for the busa forks then what is the benefit of going through all that trouble and added money?

I have already bought wheels and front discs for the bike and would rather not do that again for a 1k setup

 

[sean06]

And do offset triples just pull the whole fork setup back or does it derake the forks, or a combo of both?

 

[sean06]

yep... I'll post pics thru out the change so you guys can see how to do it

sounds good

 

[bigfootatplay]

And do offset triples just pull the whole fork setup back or does it derake the forks, or a combo of both?

??? not 100% sure about amount of derake

 

[Draco1340]

Sean,
Need to look into the speedcel battery. I think the stock lead acid battery is around 9 lbs. This is a photo from last year showing the rear subframe in fabrication. The stock subframe is over 14 lbs. The new subframe made of .025 moly was 4.9 lbs with hardware and after powdercoating.

 

[Draco1340]

Here is a pic of the frame mod done just below the ram air inlets, and the photo of the removed metal on the scale. Its a lot of work for less than a pound.

 

[Draco1340]

I think I've removed about 3/4 of a pound of aluminum from the inside runners of this damn head this week. I guesse that doesn't count?

 

[Commuta_Busa]

the tank is a big one.
also any glass body work you get can be sanded down on the inside a bit more to lower the weight. CF would be ideal but costly. Paint is the other thing. It's heavy!

I would lighten the subframe some more. I have a stock Gen 1 aluminum one that I wideled down to 3.153 lbs so your chromemoly one could go on more of a diet.

Same goes for the front brace. I ground mine down a bit, trimmed anything extra and made swiss cheese of it.

Don't replace bolts with Titanium unless they're stressed bolts. I've swapped to Ti on the pinch bolts, yoke bolts, caliper mount bolts, and a few other places as well. Other bolts I swapped to aluminum. The stator cover, igntion cover, clutch cover, oil pan, and a few others.

Loose the kickstand and the mounting bracket if possible or at least swiss cheese and grind down the bracket a bit.

I don't run an oil cooler on my NA engine and the oil temp has been fine except on long successive dyno runs.

I would say to swap the front with a BST and just rework your center of gravity to compensate as much as possible.

Polishing the frame can help reduce some weight too but the maintenance is high. Try and stay away from powder coat because it's heavy too. I sprayed my chromemoly battery box with as little primer as possible just to prevent rust. I may consider switching to an aluminum one if I can keep the assembly weight the same or less.

I looked at LiPo batteries in the past but I still don't feel comfortable with the investment. The busa engine pulls alot of watts at full song.