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Is my bike ok?
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15,025 Posts
Discussion Starter · #1 ·
Bear with me as I'm not exactly sure what I'm thinking about, but I have an idea.

There's a couple pieces of info I need, though.

What does the frame of a 07-08 GSXR weigh? No FE or S-arm. Just the frame.

Rough dimensions of the engine.

Thanks. I'll explain better later. I may have a project for the winter build off!
 

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lb/hp is what it's about!
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10,448 Posts
Contact Piester. He put a 08 1k motor in his older gsxr so he might be able to get you rough dimensions. If you would have posted this yesterday morning I would have been able to get you dimensions of my 06 1k motor. I don't know for sure exactly how much the frames weigh but I had no problems picking up the rolling chassis (frame, forks, sa, brakes, wheels w/ tires) of my 06 1k and carrying it across the garage. If I had to guess I'd say maybe 150 for that stuff.
 

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Is my bike ok?
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15,025 Posts
Discussion Starter · #3 ·
Thanks bud. I might shoot him a pm.

Ok, here's my thoughts. Watched a buddy at the drags yesterday. Literally, it was a sea of stock GSXR 1000's and Kawasaki (ZX10 ?)1000's with bolt on swingarms. That's it. Eeeeevery bike there was using the same "Hardcore" brand arm and whatever wheels came stock on their bike. Eeeeevery bike has the same 30hp shot of NOS. Bleh. Zero engine work. Zero attempt to shave pounds.

But, my buddy was KILLING them due to the fact that he weighs 30-50 lbs less than the other riders.

Huh.

Well, I miss drag racing. I LOVE the sport and the thrill of competition. Basically, I stop drag racing cars because I was bored with bracket or index racing, but I can't spend to run heads up.

This bike class is heads up. Oh yeah! :thumbsup:

I checked on the class rules:

1: no wheelie bars
2: run what ya brung

Yes!!!

So, my idea is as follows. Any and ALL input appreciated!

-Buy GSXR 1000 engine
- Install on 79-83 CB 750 chassis
- Build required swing arm
- Run spindly 33mm CB 550 front end ( low weight)
- Run narrow front tire. Probably a 1.85 alloy rim with AL spokes

Basically the above was my ideas concerning saving weight over the rigid stock frame, beefy forks and wide-tire- carrying sport bike front wheel that everyone else is still using.

These are extremely cheap and easy things to do.

More drastic ideas:

- Remove all switch gear ,lites, gauges, etc. and run only a starter button, shift button and shift light.
- Dump heavy stock exhaust/ cans for light weight bits
- Go to alky and drop the entire cooling system ( massive weight loss plus no parasitic drag of the water pump.
- Actually go in the engine. Nobody else has! Cams? Porting? Remove charging rotor? I need to learn the specific of these engines, but those are fairly simple, cheap places to gain HP
-Then just learn to ride.

Seriously, its a sea of stock liter bikes running long arms. If a guy even TRIED to run a lightweight bike he could dominate and bring home the purse every weekend. These guys are so lost they are asking each other which way the valve twists to open the nitrous bottle. And they keep coolers of ice water with a towel inside. They toss the towel over the nitrous bottle between runs to keep it chilled :doh:

So the short version.

- use their proven engine
- improve it slightly
-build light weight bike for said engine
- use old, cool bike because looking like everyone else is boring
- HEAT the bottle for proper temp/pressure/performance
-look silly racing against modern bikes using a toob frame, old school body panels and spoke front wheel
- win

Now, reality check time. I don't know how to ride. I don't know how to tune these bikes. But, these guys know fuckall and I'm a pretty fast learner of anything mechanical.

I wanna do this. I really think I can dominate this class with just a little common sense in setting up a light weight bike.

Thoughts?? I'm all ears.
 

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Remi's Dad
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17,593 Posts
It's doable. You'd have to do some major frame mods on the bottom rail and possibly mess with the pivot.

But your main area of concern is air box/t-body area it will be tight.

I've seen gsxr motors in quads and dirt bikes (with relocated fuel tanks)
 

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lɐʇuǝɯᴉɹǝdx&#4
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3,516 Posts
You can probably do much better than the NOS systems they are running. 30hp is puny. Besides keeping the tank pressure up, what you'd really want is a progressive system that kicks in gradually after launch to reduce engine / drive stress and wheel spin. Costs more, but would be cheaper than diving into the engine internals to get the same hp gains.
 

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The Hell You Say!!
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2,956 Posts
Why not a bandit 1200 motor? The fit pretty easy in the dohc frames and I have one with no title that I will be willing to let go of. Other than that sounds like you will be destroying these guys once it's built.
 

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Is my bike ok?
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15,025 Posts
Discussion Starter · #10 ·
It's doable. You'd have to do some major frame mods on the bottom rail and possibly mess with the pivot.

But your main area of concern is air box/t-body area it will be tight.

I've seen gsxr motors in quads and dirt bikes (with relocated fuel tanks)
Frame mods are fine. I was thinking that a gsxr's stock rake and trail is probably not optimum for straight line duty anyway. I'd probably goose neck the frame a couple inches and scoot the tank and seat up to match. Help get me to be putting weight up front that way,too.
 

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Super Moderator
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3,038 Posts
Eeeeevery bike has the same 30hp shot of NOS. Bleh.

The reason most of those guys are running only a 30HP shot of NO2 is because they're probably running a dry shot which limits them to about 30-40HP with the stock injectors.

UF is right though, it's going to take quite a bit of work in the backbone area of any old school steel frame for the TB's and airbox.

I say go for it, but expect some major chassis surgery and suspension tweaking to get it down the track in a decent fashion.

Later, Doug
 
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Is my bike ok?
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15,025 Posts
Discussion Starter · #12 ·
You can probably do much better than the NOS systems they are running. 30hp is puny. Besides keeping the tank pressure up, what you'd really want is a progressive system that kicks in gradually after launch to reduce engine / drive stress and wheel spin. Costs more, but would be cheaper than diving into the engine internals to get the same hp gains.
Definitely!!

Apparently, the 30-35 HP systems with as a simple bolt on to the bike without any additional tuning whatsoever. It's an easy 2-3 tenths and doesn't require and special rings or timing adjustments. Just a lil better fuel.

Progressive and multi state systems could definitely prove useful without a wheelie bar.

Nitrous is just silly easy power. Hard to ignore this option, but I need to research the limits of these engines on spray. Apparently 35-40 is all these guys play with and it doesn't stress the engine or stock clutch at all.
 

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Is my bike ok?
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15,025 Posts
Discussion Starter · #14 ·
Why not a bandit 1200 motor? The fit pretty easy in the dohc frames and I have one with no title that I will be willing to let go of. Other than that sounds like you will be destroying these guys once it's built.
Bingo!! One of my first thoughts as well. For one, there's no cooling system to deal with. Huge plus!

But, I don't know how they compare to the GSXR 1000 on power. The big torque could be a downfall on a no-wheeliebar class. And I'm not sure they have the top end charge the GSXR has or not.

Also, I'm curious how it compares on weight . But this was definitely something I wanted to talk about, too.

I'm not dead set on a 07-09 GSXR 1000 , but it's my best reference point at the time.


Guys, thank a TON for your input. I was afraid I might get the cold shoulder as soon as I mentioned extended swing arms. :D

For reference, I know I can get a bare CB frame usable for this to come in under 40 lbs. I'm still curious what a stock GSXR frame comes in at. Haven't had time to see serious research yet.
 

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lb/hp is what it's about!
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10,448 Posts
A modified cb frame at 40# is really heavy. Should be able to easily build a frame for a cb that's under 30#. Even the frame I built for my xs650 street tracker build is 17.5# if I remember correctly.

Did a quick search and a bare chassis for the 03-04 gsxr1000 weighs 25.5#.
 

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Is my bike ok?
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15,025 Posts
Discussion Starter · #18 ·
A modified cb frame at 40# is really heavy. Should be able to easily build a frame for a cb that's under 30#. Even the frame I built for my xs650 street tracker build is 17.5# if I remember correctly.

Did a quick search and a bare chassis for the 03-04 gsxr1000 weighs 25.5#.
It was a rough estimate based on my current '78 build. That frame has a pretty substantial tail portion added on. A drag bike will require basically no tall at all.

Thanks for that info. 25 lbs will be a hard number to beat.
 

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hate us cuz they ainus
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1,827 Posts
I dunno the answer for sure but it does seem like Suzuki has kinda been resting on their laurels the past couple years. Seems like all they wanna do anymore is give everyone a new headlight every couple years?
 
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