New shock absorbing seats built and designed by Two Cocks Racing
 

im getting boat brain again.. here are the new shock absorbing seats going in the race boat.. should fit nicely in front of the new power:)

http://i282.photobucket.com/albums/k...ness1/1340.jpg
http://i282.photobucket.com/albums/k...ness1/1331.jpg
http://i282.photobucket.com/albums/k...ness1/1341.jpg

Looks very nice. If those open ends on the uncapped tubing bothers you, M&P Pipe & Flange make square and rectangle tubing caps for varying wall thicknesses. Probably .10 a piece or so. Pop right in, and look nice and finished.

Looks the one on the floor has them already.
Very nice seat and easy to build to.

Very cool, how much do they weigh?
Dean

How do you work out the shock settings and spring rate?

Might it give you the feeling of getting throw into the dash with the rear pivot design? With a front pivot it would at least get some more travel at your spine. I might be wrong.

Awesome....the boat is sick as well! Any chance of running in Michigan City this year on the SBI Circuit?

Wrong harness mounting

Proper mount should be behind the shoulder and at no more than 7 degrees deflection

How that would ever pass any sort of tech inspection is beyond me

Any impact or rapid decell would cause spinal compression....

Nice, I like the simplicity of the design. You will love having that extra little bit of cusion to take the edge off some of the bone jarring hits out there. Something to think about you might want to put a limiting strap or chain or something on the front of it. If you ever go over you want to be able to have control on the negative travel. Not sure how the shock would handle overlimiting in that direction and judging my the length of the swing arm you could generate a lot of pulling force on it. Just a thought, looks good though.


Teds got a good point, i am seeing a max of twenty degrees according to Linder guidlines. Also showing a max degree of recline of twenty seven degrees, looks like your within that pretty good. (info courtesy of Linder guidlines but dated 1999)

thanks for all the feedback and great point about mounting position of shoulder harness...

funny you said that because i actually used the mounting positions from the previous belts that were installed in the boat in the design of these seats..... the boat has never failed inspection?

just pulled out rci's paperwork and they were mounted excatly where they were not sopposed to be... no wonder my backs not been the same since kw.

the shock is 100% adjustable in ride and height. the rear pivot point gives a feeling that is extremely unique (better) IMO. seems to work better because of the direction of impact and boat additude during rough conditions...

they weighed 48.7lbs.. a little heavy to use racing this season which is why we have already started a full carbon fiber design... now with a harness mount adjustment:)

YES! we will be in michigan city this year! hoping some of the unlimited boys step up this year.. we'll see?

Fixx
 

Cool design,,if the spring shock gets to be to much try the fox floats,,i know this is boat racing but mabe they will have the sive you may want to try..they are fully adjustable up and down with the internal valving,also you can adjust the rebound rate with a air hand pump..

this is a snomobile version but they may have a shock that will work for you..

http://www.foxracingshox.com/snowmob...e/FLOAT_X_EVOL

That is great that you guy's will be making the haul out to Michigan City....I think you will find that there is a huge Performance Boat scene when you arrive. This is going to be the third year for the race....the spectator fleet is continuing to grow and we hope the race boat count will as well. Myself and alot of the Chi Town crew will be there all weekend staying on our boats and hangin' out....we can't wait!

A couple of ideas to consider.

1. Use a one piece 180 degree hoop for the upper mount
for the shock. This would eliminate four welded joints
and lighten it up a little.

2. Change the rear frame pivot to allow for the bolts to be
stressed in double shear as opposed to the single shear
situation they are in now. This will make it stronger as
well as taking some of the "slop" out of it.

Roger

Look great Andy !
What are some good shock choices when building your own ?
Any air ones out there that don't require on onboard compressor.
Those Fox EVOL's seem a lil pricey .

the rear bolts could use some support, nice seats.

Wow !! Andy brought one of the new Two Cocks race seats by the shop on friday. We talked about the design and a few possiable engineering and material changes and these things are gonna be GREAT!! I strapped in and had a a couple of guys pick me up and drop me onto the concrete and they work really nice now. I think that the way they are hinged and the attitude a boat usually has on landing will translate into a very neutral feeling. Good luck on these Andy. They have a lot of promise.

how have these seats faired for the season?? like em?

How were they at Key West? You guys looked good out on the course.

Looks great. I searched for "suspension seats" and this thread didn't come up.

What shock are you using? What would you change if you built them again?

The seats are incredible, a night and day difference between using them and not using them. especially in race situations.

We used fox racing shocks from a quad. We learned a lot this racing season so the design is changing to improve safety and to try and remove some weight also.

The coolest feeling in the world now is when i apply power the seats actually raise about an inch and a half under acceleration. Then, when i let out of the throttle the seats compress and absorb even the smallest disturbance in the water, making you feel weightless...

The seats are incredible, a night and day difference between using them and not using them. especially in race situations.

We used fox racing shocks from a quad. We learned a lot this racing season so the design is changing to improve safety and to try and remove some weight also.

The coolest feeling in the world now is when i apply power the seats actually raise about an inch and a half under acceleration. Then, when i let out of the throttle the seats compress and absorb even the smallest disturbance in the water, making you feel weightless...

a little look inside
http://i282.photobucket.com/albums/k...72492031_n.jpg

It's good to see that you use genuine racing seats with side supports for the head!

The seat is an important part of the safety system but often forgotten.

Seat belt geometry has already been mentioned in the thread. What does your regulations say? I would recommend you mount your belts horizontal for two reasons.

1. It's HANS compatible if you plan to use them in the future.
2. The belt geometry recommended by belt manufacturers are based on a horizontal impact. Since stuffs rarely are perfectly horizontal a downward routing of the shoulder belt will put unnecessary forces on the spine. The same goes for impacting the water up side down.

http://www.schroth.com/installation-.../image_032.gif

Since you are updating the design, have you thought about triangulating the upper seat belt mounts (green lines)? Any flex in the fixations will generate slack which is bad for the occupant.

https://lh3.googleusercontent.com/-6...s640/13312.jpg

You can easily test the strength of the belt fixations if you bolt the frame to the shop floor and pull them with a truck or similar. Some scales from a crane will keep track of the pulling force. Your regulation might use other forces though.

It is if utmost importance that the seat and belt fixations are strong enough to restrain the occupant. Especially in a race boat where you might have to evacuate quickly.

Just my 2 cents.

Those are awesome! It's great that you kept the design simple. I see you said they were quad shocks. They look close to the front torque arm shocks on a Polaris ProX.

here is a pic of how we solved the shoulder mount issue

http://i282.photobucket.com/albums/k...1/photo-12.jpg

This is really great. It is a large step in saftey. I bet it will take some impact of of a crash. I have thought about using motorhome airbags in a simlar fashion to cut down on hard impacts. Boats don't really have crumple zones to absrob impact like race cars. Thanks for sharing !

It's very difficult to focus on the seat with two massive engines in the picture. :p

The belt geometry looks good with your changes! But the upper fixation looks very weak IMHO.

oh those little things... thought no one would notice.

thanks for taking the time to give your input and i do like the triangle design for added strength. The next version will probably incorporate a little of this but eliminating some weight has become part of the challenge also.

looks awesome, I agree I think the weakest point would be where the shock mounts and the weld to go up to the shoulder mount. maybe tie it in with a brace of some sort to the base where it pivots. In the event of a stuff with your weight being thrown forward I think it may have the tendency to bend there. Or if you did the uprights with cold rolled steel to achieve the proper angle instead of welded sections, it may save on weight too. have it like ( instead of the weld :)

[QUOTE]
Comment:
I agree with Dreamer here and think suspension seats are detrimental to your spine.

Here is why:
The rebound of the spring or suspension portion is always working against you when compressed. Uhhh No thanks. When your boat comes off a swell and impacts upon landing ie... similar to bottoming out your suspension and tires, there will be a rebound. If your suspension seat is compressing down while your boat is rebounding up, you are the only thing still going down but the chassis is going up. Kind of like a bat hitting a ball.

Another interesting thread can be found here when desert racers discuss this very same topic.

http://www.race-dezert.com/forum/showthread.php?t=58050

I once thought suspension seats would be great... but have changed my mind... rigid seats such as Sparcos, Corbeau, or Recaro's IMO are better. It makes a lot of sense all the desert racers, rally drivers have rigid shell type seats with minimal padding.

Do what you want... just offering another perspective for you to consider in the interest of safety.

KAP

KAP, your argument doesn't apply on Viperfitness1 seats. Since they are belt-in-seat. You will not compress the spring when putting tension on the shoulder straps. All the belt fixations are "above" the spring.

Not sure if I make any sense?

With the correct spring and damper settings the above design will reduce forces on the spine.

How would that design translate to a pleasureboat?

Comment:

Your spine is not static it will move....how do you control the g force on rebound exerted by the spring.

Where is the data on the seat? Using a ATV shock absorber on a metal frame with a rigid tub fiberglass/carbon fiber seat needs further analysis.

If your going to simply conclude that my prior post doesn't apply back it up with data and facts. I could build you one rather quickly out of square tube and use a Elka shock with preload and rebound compression adjustments. It doesn't mean it will be good for you to use!

In addition, anytime you have movement in the seat in rough environments you are moving the person in and out of the restraints. If you add another variable... holding on to the steering wheel in rough seas going up and down in a seat... it seems like a chore in and of itself and that is being diplomatic.

I would rather have someone take me through the data/analysis than conclude straight from A to Z that it works. If thats the case every Trophy truck team in town would adopt such seating arrangements. Lest you forget the Baja 1000 is a extremely long race with lots of unpredictable g forces upon the driver and co-driver. Far more than anything in a boat and for a longer distance...hours of WOT.

KAP

P.S. I don't think you can adjust a spring to absorb the compression and rebound effect on the big stuff....not without causing injury. I could be wrong but I wouldnt bet my back on it.

You guys are talking WAY over my head here but I can comment on what controls the rebound of the spring. The shock does that. The rate the shock compresses AND rebounds is controlled by valving and spring pre-load, rate, etc. It's not like the spring violently rebounds. It would be similar to the swingarm shock on a dirt bike or a rear track shock on a sled.

I can kind of put my head around what kap328 is saying. But my simple mind thinks of how my sled's rear suspension works. It compresses over bumps and obviously rebounds, both of these rates are based on spring and shock settings. I then try and picture riding with no suspension at all and it seems like the violent hits of no suspension would compress the spine far more than the rebound of the suspension.

Maybe I am way off? Like I said I have a simple mind! :D

KAP, obviously my post didn't make any sense so I'll try again.

Your argument is valid if you have a suspension seat with belt fixations in the walls and/or floor i.e fixations that doesn't move with the occupant. With that type of arrangement it is possible to pre load the spine when tensioning the shoulder belts.

But with the set up above it is not possible to pre load the spine with the spring no matter how hard you pull the shoulder belts. That is a fact.

I agree that the spring and damper needs correct performance to minimise forces on the spine.

Most of the current biomechanical data regarding spinal compression comes from the US military. More specificity from helicopter seats designed to prevent spinal injury in case of a crash. Some of this data is public. But it is also based on data from young men in excellent physical condition so it is natural to assume that that average Joe will have a lower g-force threshold.

I need to check the the actual limits since I don't trust my my memory...

But for the sake of argument let's say that the limit is 10G.
The use of Newtons second law give us a force that needs to be matched by the spring damper system.

The mass of the seat and occupant= M

Mx10G= F
F is the maximum force the spring and damper should generate in an compression.
Some additional math will give recommended values for the spring and damper.
I'll check some data and we can do the math in this thread if that is ok?

What type of spinal fractures are common in off-road racing? Burst, wedge or flexion and distraction?

Kap, Thank you for taking time to offer a valid concern. However i believe you are comparing apples to oranges with suspension seats previously used in off road truck racing. Maybe you should send those guys a link to this thread so they can see how i have solved the issues you are describing with shock absorbing seats.

IMO gripenland is on the right track on how to make the upper half more rigid in the event of a sudden stop in any direction. i like the idea of cold rolled steel tubing for the framing and is the direction we are headed...

In my short career as a boat racer i have figured out one thing. You CAN NOT strap yourself to a rigid seat in a vee bottom boat @130 mph and hit a set of 6-8 footers and expect your back to absorb the impact. It is physically impossible. Trust me!

Safety is and will remain the top priority in our program. But absorbing the shock of waves the boat impacts under high speeds is a MUST for powerboating safety! and thats the bottom line.

I have crash tested a few belt-in-seats in my career. Both with and without shock absorbing.

All of them has failed the first test due to strength issues. Failed hinges, failed seat belt fixations, failed floor fixations and so on.
And they have been seats made by large seat manufacturers...

The forces are a lot higher then you might think so a shock absorbing seat will be heavy.

If the seat and frame are not strong enough the seat belt will only create a false sense of security.


If it was me who were building a shock absorbing seat I would:

• Use a metal frame. Robust, cheap, easy to change and strong.
• Test the strength by pulling the seat fixation points.
• When the frame is strong enough to pass the pulling test I would bring out the drill and drill a few holes to reduce weight.
• Test it again, drill some more holes, test, drill, test, drill and so on

But that is just me. There are many ways to build and test a seat. Just sharing some thoughts on the subject.

I love a post with good knowledgable points made about interesting subjects. Hey Vipe, update this thread when you start running, especially in the rough stuff. Hope it all makes for a better ride while you're whaling the tar out of the whole package.

Hello Viperfitness:

In automotive racing you have about 5.5g of lateral force constantly on a driver in oval tracks. In off road racing you have various loads on the driver and co-driver in excess of 6g's both in flexion and compression type situations.

This brief video demonstrates what types of forces I was talking about. The vehicle has tub style seating with minimal padding...typically Sparco or same or similar seating.

Baja 1000 is 1000miles in about 18 hours....brutal IMO.

Let me know when you get one of those seats into a Trophy truck.

[YOUTUBE]http://www.youtube.com/watch?v=88rkNR_n9_0[/YOUTUBE]

This video demonstrates the rebound and compression forces they contend with in one race. Try that with your suspension seat you really would not make it past the first jump.....and or be in control of the truck.

Good luck on your endeavor.

KAP

P.S. I really considered suspension seats for my boat but everything I researched indicated I would be far better with a kevlar/carbonfiber tub style seat.

As for the best suspension seats for a v-bottom.. they are your legs...take a look at some of the Mc Manus Apache videos. The crew in the boat is standing up:drink:.

As a complete outsider, I don't know how you can compare the two. The trucks have a suspensions, boats don't. If those trucks has both a truck and seat suspension, many times they would be out of sync making it nearly impossible to drive, but in a boat, the only minor give you would get is through the viscosity of the water. I think the idea of a suspension seat in a boat is a great idea....in a Baja truck, not so much.

I see how a trophy with seat suspension could be at opposite ends on both their available travel but not in a boat. In layman's terms, I think you are describing what its like to jump on a trampoline that someone else is jumping on. Sometimes it can launch you higher, and other times it can buckle your knees, or even stop you dead.