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Mad Scientist
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640 Posts
Discussion Starter #1 (Edited)
Are you guys ready for this ?
Added 2.2kg to the crank right out wide. This is an extreme amount but need to know what effect adding too much weight might have. Hopefully increase cornering speed by smoothing out the power. This is my 98R1 but i will be doing this same mod to my CBR (if it works)












http://www.youtube.com/watch?v=SpUEJBb3CMY
 

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Mad Scientist
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640 Posts
Discussion Starter #3
IT WORKS !!!!!!!!!!!!!
Did a ride day at the Creek today and........
The Crankshaft mod not only didnt blow up but actually performed quite well and had the predicted effect on corner exits.
You could apply more throttle earlier.
You could apply throttle at full lean angle.
It was smooth and safe feeling. It gave confidence in the bike and tires.
In those long lingering corners that seem to go on for ever and force you to feather the throttle now are done under throttle and accelerating (and leaving long fat rubber trails).
I found I was hooking the bike from apex to exit on full angle and ramping the throttle up much quicker than I used to and much quicker than on the CBR.
The bike seemed to turn very aggressively and maintain more of an angle until later in the turn. Turns seemed to be longer ie more linked together because I didnt have to be upright to be on the gas. Corner speed is now a product of how much centrifugal force the tires can handle from the bike going around a corner not how well they can handle engine power.
This bone stock 98R1 is less than a second slower than my 152kg CBR around Eastern Creek.
When I say bone stock Im talking about engine power up mods. Stock cams, pistons and compression. It has a Dynojet kit in the carbs. It has stock suspension !!!!!! The front caliper rubbers just decided to swell up and jam the pistons and they were dragging the whole time. Also didnt have a screen and couldnt hold it flat down the straight. Clutch was slipping in higher gears in spite of me putting a shim under the diaphram.It has undergone extensive lightening like my CBR but dont know how much it weighes. Could be 155kg.
The extra weight in the crank didnt have any side effects in braking or yawing the bike.
Definitely doing this mod to my CBR. Going to take as much weight of it before welding the rings on. Probly weld at least 4 rings.
Will post some pics later .
 

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Mad Scientist
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640 Posts
Discussion Starter #4
heres some shots
on the gas

traffic


Tiffany or someone

t2 or something

t3

t9 bumper with mate Gary

One last one from a mate and no fkn watermarks

we have animals on our tracks. I nearly i hit this guy in T1 doing 190kmh
 

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Mad Scientist
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640 Posts
Discussion Starter #6
That R6 bodywork looks cool on your bike.
Thanks
that was its only chance in hell of ever looking good
Most R1 fairings are big and bulky.
got a red tinted screen on order
 

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Track bound.
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9,822 Posts
Cool experiment! I can definitely see the added crank inertia giving more confidence on the throttle. The trade off I see is the added flywheel effect will make the bike slower to steer.
 

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DILLIGAF
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4,472 Posts
Very cool man. Was that a turtle on the track?:scared
 

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Mad Scientist
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640 Posts
Discussion Starter #9
Cool experiment! I can definitely see the added crank inertia giving more confidence on the throttle. The trade off I see is the added flywheel effect will make the bike slower to steer.
The bike still dropped to full angle very quickly. It has Dymag Carbons which help with that. Another thing that helps with flywheel effect is the 70 profile rear tire. They are know to give good drive out of corners cause they are bloody heavy and that weight is carried right out at the perimeter of the wheel.
This particular Dymag rear wheel has had its cush drive removed and bearing carrier and sprocket bolt together with 6 alloy bolts instead of 10 steel ones.
But once you got to full angle it held line very aggressively and never wanted to run wide in spite of its crap suspension.
You just held a tight line and kept rolling on more throttle till you started to come close to the gravel or ripple.

Was that a turtle on the track?
Yep there were a few of them. I thought it was a part off a bike but got closer and he had his neck stretched out and he was running for his life.
Never seen a turtle move that quick.
 

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Track bound.
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9,822 Posts
Well, the carbon wheels will help reduce the flywheel effect, but the big heavy slick actually adds to it and makes it worse...
 

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Premium Member
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23,052 Posts
rather than do all the welding, just use Mallory metal, its made for adding weight to crankshafts...you drill into your counter weight, press the mallory in and your set.

And we have turtles that walk onto my local track, was really bad when they first opened, we call them walking knee pucks.
 

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Registered
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217 Posts
I was told that a crankshaft cant be balanced by itself. Since its part of a system, a proper balance would include the rods and pistons and even flywheel. Unless all those parts weigh exactly the same. But hey, that guy i heard that from could've been wrong.
 

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Mad Scientist
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640 Posts
Discussion Starter #13
I was told that a crankshaft cant be balanced by itself. Since its part of a system, a proper balance would include the rods and pistons and even flywheel. Unless all those parts weigh exactly the same. But hey, that guy i heard that from could've been wrong.
Hes right and wrong.
Line 4 single plane crank engines are automatically balanced cause they have 2 pistons up and 2 down. The counter weights are just for flywheel effect. This is probly the only engine that doesnt need a counter balance crank

Line 4 cross plane crank engines are different. Each piston/rod has its own counter balancer which also doubles as flywheel effect. That goes for any other engine too.
 

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Mad Scientist
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640 Posts
Discussion Starter #14 (Edited)
Another Eastern Creek track day under its belt and still going strong.
Got 4 full sessions and with a kit in the calipers and a ZX10 master it finally has brakes that Im comfortable with. Lifting the rear into T2 with 1 finger.
Clutch still slipping but all in all was able to concentrate on the Flywheel business and how well it works.
Also got to weigh the bike and its the same as my 04CBR 152kg (335lbs)
but Im damn sure it gets faster laps despite being 25hp short on power.
Im now getting bigger lean angles on this bike than Ive ever had in my life. Im scrapping the knee block on any corner and Im not usually a knee scrapper at all because of my riding style and kooky body position on the bike.
This bike goes round corners like an electron in a Hadron Colider. I can go around the outside or inside of any bike in almost any corner including Desmoseidici's. But Im getting away from more powerfull bikes by powering out of corners earlier.
I did manage to bust the rear loose on full angle on one exit by gassing too early but I was deliberately pushing it and got it back in time.

I dont know about you seppo's but we got Desmoseidici's coming out of our ears down here. All owned by rich business types who cant actually ride but love the jewellery factor of owning a $100k bike.


round the outside



k open her up..now Ah its already is open. 136hp is not enough for this track

round the outside again. Doesnt this guy know any other tricks

needs more stickers
 
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