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Assalt Weapan Bonneville 2007 Effort, Chapter 2

The Culmination Of A Plan--We Made It!

By The 5-Ball Racing Team
5/21/2010 10:07:15 AM

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Here’s a racer from 1936. Hopefully we’ll kick his ass.

Okay, we had a plan, like a musician with a blank sheet of music paper and a rhythm running through his mind. I had a notion based on every element I absorbed on the salt in 2006 and a myriad of conversations since. Time is also a constant obstacle and since I’m a deadline freak, I set one. I wanted the roller, frame, wheels and front end in my hands close to the end of the year. At this writing session, in my unheated shop the day after Christmas, with a dinky desk warmer blowing under my chair, I have six days left. No pressure...

fab kevin
But first we needed a laser-cut 5-Ball racing sign from Kevin Baas.

My first wheel guy bailed and I’m waiting for a call from Kim Hotinger regarding American and Renegade Wheels. Leo DiOrio, Leos Custom Cycle Supply, Ph# 303 438 8991,           is poised to fabricate our girder front end, to deliver the exact trail requested, and Rick Krost has a frame in stock from U.S. Choppers, to be modified, but we needed to nail down our plan, which is critical. We must determine the stretch behind the tranny and up front so Valerie Thompson will be poised for 200 mph on the salt. She must work with the machine’s aerodynamics for the best speed, comfort and safe handling. We're not asking much.

CKat bench
Chris Kallas working on a chopper concept drawing when he should be working on the World's Fastest Panhead. We're investigating.

We are extremely fortunate to have an excellent team behind us who are ecstatic to dig for precise performance information. Our concept drawing slipped through a number of stages behind the talented hands of Chris Kallas our 5-Ball Racing Official, accredited and sanctioned artist. With each rendition I submitted the most-excellent art to Berry Wardlaw, the Accurate Engineering engine master, Leo DiOrio, Wil Phillips and often Rodan from the SCTA, for rule requirements. Below you will stumble on thoughts from various team members regarding girder handling, Valerie’s measurements, the engine and the concept progression from art to actual measurements.


Leo DiOrio On Girders:

I am ready to start doing the front end, so when the frame is finished, and we have some tire diameters to work with we can do the actual geometry. I will make some recommendations as we go down that road here is one or two of many things we should think about as we go so the whole thing comes together nicely does the frame maker have any models or prints or samples of the neck he uses? This will aid in the fork stop and stem configuration, also has Valerie given you any input on how much steering effort goes into driving on the salt the reason I ask is if we want to do something special in the the way of handle bars I would make provisions for that in the top clamp. I would think this might come into play when mocking up her riding position to create the mold.


I won’t throw all girders into this discussion without studying a few (how they work trail wise category) however I can tell simply how this one works, and here are some key points:

1. the center of the wheel is much further ahead of the centerline of the steering head.

2. Since we have twice as many links triple clamps and control arms and the shock resting within this mechanism, that isn't required to be relative in angle to the girder blades, as opposed to a conventional front end which consists of a pair of triple clamps and suspension system always running on centerline to the fork tubes. So we can increase the trail by moving either the upper clamps offset forward, or using what is effectively a longer upper control arm, or by doing the opposite of all that on the lower links (triple clamp control arms), and of course, the opposite of all that is designed to decrease the trail. With all those links and the shock position controlling the relationship angle of the suspension to the surface you are riding on, if you use all those links and shock position you can tailor the front-end to do whatever is best for the application.

There is a lot more to them, so much it will just make you sleepy.


As far as measuring it goes, as the frame gets to where we can get some dimensions, I will do all the length and trail calculations and travel requirements in the computer. This will tell me what to make, so when Valerie returns from her 200 MPH cruise, she will say it was like driving a towncar for a Lincoln commercial.

Rogers Goldammer’s bike had 5.5 inches of trail, however it’s a lot lighter than the Assalt Weapan, although Valerie is much lighter than Rodger and we are looking for higher speeds than Rodger hit. We should run more trail.

Do you and the crew believe there are faster wheel patterns than others in the world of every little bit helps? I think the fender design will effect what wheel pattern works best once you get the wheel pattern worked out I will be glad to take on hub design if you wanted It just makes sense I'm doing the front axle assembly. One last thing, and it’s no big deal.

Rick with his torch fired up for action.

Now Let’s Hear From Rick Krost (as in toast), of U.S. Choppers:

Dig it...... I have some crazy ideas (usually just because I refuse to listen to anyone).... but I would like to see some 200mph bikes if you have any pics (pass them my way). I'm really thinking there is a lot of innate streamlining in my frame.... I keep looking at our sketch (nothing taken away from Chris and his art), but I think that thing will catch more wind than a sail. In my mind, I envision the front wheel tighter to the mass of the bike (i.e. more rake in trees-less in neck, or offset the wheel even).

Secondly, my thoughts on the low to the ground deal (I agree- but only somewhat)...... I would think that if you push the wind down in front- then it should stay down until exit at rear. However, there is nothing wrong with wind chasing a pattern like you see in mother nature around cliffs etc (Lake Powell)..... wind can actually increase velocity in a cone!! So my thoughts are more at directing the wind rather than just "getting low". IE- if we direct the wind UP in front of the bike and to the SIDE, we then transition it to a point in the tail section which would mirror my frame lines- this will channel the wind into a pinpoint exit versus hitting a giant cowl and dragging.

So I picture Valerie laying down, the wind deflected just to her helmet, following down her back into a small rear "turtle" point (wind now hugging and traveling down). Conversely, the wind pushed to the side from the tire and front end gets directed not down, but across the side of the bike and frame rails then directed up the frame rails to a point on the rear "turtle" that merges it with the top wind flow, so that both directed wind flows exit at the same tip (Just like an airplane).

Regarding down force, I say we fill the camel (turtle) with sand..... with both her feet and sand over the tire- I think the rear end will sit pat.

Heck, I don't know, just a thought to throw your way. Let me know what your thoughts are.... remember I'm a ghetto mechanic.

U.S. Choppers
2039 S. Lyon St
Santa Ana, CA 92705
Appointments Only Please


Here’s Berry Wardlaw of Accurate Engineering on The Engine:

The engine I am building now is NOTHING like your street engine. I'm really shooting for over 200 hp. Now that's pressure. I have gathered a mountain of information and John (Andrews) is building the camshaft but he is also doing 4 other custom grinds and the Crocker cams, so I know that will take 5-6 weeks. I do however have your heads, the titanium valves, springs, etc..."

Reliability is why I am taking pain staking measures in machining, assembly, reading, asking questions, researching, etc. We can't win if we can't finish. The aluminum rods will absorb some of the shock load when we hit the 100-150 hp shot of nitrous. We will definitely work the nitrous loads up VERY carefully. Remember we need two exhaust gas temperature gauges, one for each pipe, so when we hit the nitrous she can watch the temperature to make sure the nitrous is working. If the nitrous fails she will simply let off the button.

I am on my way home to finish the last details of the engine on the computer then on to the flow bench. Aluminum, titanium, magnesium, beryllium, nitrous Panhead. Say that three times fast. No word yet on my/your cam from John. This is going to be the nicest engine I have ever built, God I hope it works! Hey, do we get to ride it after the "Girl"?

We are working with S&S for the following components although later, we discovered, some of the elements didn’t fit into our formula.

1. Aluminum rod set, 8.000", .927 wrist pin. #34-7222.
2. 1.500" tapered crank pin w/nuts for 1981-up flywheels. #34-2180.
3. 1981-up 4.500" stroke flywheels, stock diameter for 1.500" crankpin.

Accurate Eng. Banner

Talked to Mil. I already had the S&S ignition and the reverse gears for your engine. Right now I am trying to hustle S&S out of a set of aluminum rods, Axtell out of some free cylinders and blank pistons. Hell, I'm lookin' fer' anything free.


Cinci Feb 2006 0321
This is the powerplant behind the Salt Shaker and the Assalt Weapan.

We are working on an article about Berry's engines, his performance philosophies and guidelines for a 2007 Panhead motor. Hang on for that one.


V-rod headlight
Here’s the unit with one of the initial sketches. It sports the V-Rod headlight and an illegal rear fender.

The V-Rod Connection:

I can tell from the art that the possibilities for great things are emerging. Are you still planning on not using a front brake? A V-Rod headlight might make for some good streamlining based on its shape. Not that it is any of my biz except if you use a headlight I should make provisions to mount it.

Ask the frame maker, if between 32 to 34 degrees of rake fits into the plan. We can achieve the desired trail with almost any rake; however if we keep the rake in this range, it will make the gap between the rear of the front wheel and the front of the motor smaller to help with the overall aerodynamics.

--Leo DiOrio
Leos custom cycle supply
Ph# 303 438 8991


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Here’s Valerie stretched out, farther than Berry Wardlaw liked. It’s with no headlight and the bad rear fender.

Thoughts from A Bonneville Veteran and Bikernet Reader:

I have had the privilege to work the start/finish line at the last 2 BUB events. My Dad and I ran the 8 mile last year and I was at the 5 mile in 2005. I have been keeping in touch with Valerie via E-mail since the last BUB event and I would love to see her get into the 200 MPH Club.

The fact that she could do it with a Panhead motor would make it that much better! I have been reading about the (Assault Weapon) concept bike on your web site and I think you are on the right track to achieve your 200MPH goal. Aero + HP + traction = SPEED. I have 2 ideas you might want to think about.

1) Traction: John Noonan on his recorderd setting Hyabusa, (almost 260MPH) attaches 175lb of lead weight on his swing arm to gain more traction on the salt. Every bike will hit its "Aero wall" and no amount of HP will make it go faster on the salt. The rear tire will just break loose. Valerie has many talents but weight on the rear tire is not one of them.

2) The rules say you can only Streamline the bike so much. The rules do not say how much you can streamline the rider. It would seem to me that a riders leathers and speed hump could be fashioned to create more down force on the rear tire and still be slippery in the wind.

Wishing you the very best of luck at the 2007 Speed Trials by Bub, and I look forward to seeing you on the salt!

"Robert Collier"


Okay, so nailing down the actual configuration for the Assalt Weapan involved one critical aspect, Valerie’s size. We needed to see if my creativity abilities and actual measurements worked together. Snagging dimensions from a woman is a chore, but she finally came around.

Valerie Thompson On Measurements:

Okay...I'm doing it right now. I just forgot measurements from where to where...?

I'm 5'4 3/4, 105-110 Lbs, hip to ground 38 inches, helmet to hip 3, shoulder to fingers 29. Does this help..?

How about this: 68 inches with helmet, 31 crotch to shoe, 22 shoulder to wrist, and 16 shoulder to shoulder.

Is this good?


AWbentlegtrimmed fender 
This one was getting close with the required rear fender. The rim must show directly above the axle. This one has her leg bent slightly for better manuevering and balance. Finally, the headlight is an approved model. A V-rod headlight on any other bike is considered streamlining.

Once the measurements were forthcoming Chris Kallas and I started working toward a scale drawing. Rough measurements indicated dismal results. We might be forced to stretch the frame a foot forward and a foot to the rear. That concerned me from several aspects. I didn’t like the notion of a flopping chain, and I was severely concerned about frame flexing, although Rodan assured me that the longer a frame is the more straight it goes. I still prayed for a tight extended frame. Then Rick Krost poored forth his philosophies:

Lets say we are around 68" wheel base to start.... then we add 12" getting 80" wheelbase........ after that I would figure we would need a truss type frame (like a drag bike) for structural integrity like you mentioned before. If we go a foot on each end, we are in the 90-100 inch range which would necessitate a bridge type truss system. No matter what, we can still add stanchions in the rear and a dropped double country bar in front and rear of the motor. How many hp per inch is Berry getting us and what size motor (I am figuring normally aspirated pushrod?). It’s all reasonably easy- we just have to start at the right place!

Figure in the early days they were going 150 on little spindly frames with tiny motors and short wheelbase (and open wheels)....

It was in 1969 that Payne’s Turnip Eater set several records, including hitting a top speed of over 201 mph, en route to an average of 196.512. His trap speed of 201 made Payne the first rider in history to push a non-streamliner to over 200 mph. His bike was towed up to 70 mph before he fired it up to begin the run. To save weight he used a single-speed transmission, which meant he had to slip the clutch up to about 110 mph. That year he broke the existing class record by a margin of 43 mph.

Stock Jap bikes are coming in at around 175....... Plus you have 250mph Hayabusa's that merely have an extended swingarm and a hopped up motor......(open wheel), but then again they say it takes 8 times more horsepower to go twice as fast..... so does this mean we need 4 times more horsepower from that same motor by the same metrics???

US Chopper banner

But seriously, lets break it all down..... we are friggin pussies if we can’t do this...... here’s why:

Fastest Bicycle Speed
The highest speed ever achieved on a bicycle is 268.831 km/h (167.043 mph), by Fred Rompelberg (The Netherlands) at Bonneville Salt Flats, Utah, USA, on October 3, 1995. His record attempt was greatly assisted by the slipstream from his lead vehicle. Fred has been cycling professionally for nearly 30 years and during that time has held 11 world records.

Who: Fred Rompelberg
When: October 3, 1995
Where: Bonneville Salt Flats, Utah, USA
What: 268.831 km/h (167.043 mph)

I rest my case- let's pedal Bonny!

U.S. Choppers
2039 S. Lyon St
Santa Ana, CA 92705
Appointments Only Please

Chris felt confident with the last Black and White sketch and took it to color. Whatta ya tink? Now if we can just finish the scale drawing and begin building the frame.

Memo To 5-Ball Racing Concept Illustrator:

I took Valerie's measurements downstairs and played around with a rigid frame in the shop. I'm afraid that my design is flawed unless Valerie was a midget. I figured the frame would need to be stretched about a foot forward and another foot behind the tranny. Rick Krost is also going to confirm, but see if you can check it out.

Rick told me he has a double-downtube rigid we can work with. I told Rick we may have to stretch it 6 inches to the front and rear and see if we can work with that. The rule book states that the controls must be within 6 inches of the rear axle.



Chris Kallas Adding Dimensions To The Concept:

I've been struggling with the scale. Are you sure that the engine is the sizes you told me. I've been measuring off of some photos of the salt shaker. When I get the right height it doesn't match the width.

You gave me 20.5" W x 23" H. If I use the height at 23 I get about 21.5 wide. Is the tire diameter on the front of the salt shaker approx. 26" in diameter? If you gave me the distance from axle to axle it could help, also.

Bubs banner

I confirmed the engine measurements. The Salt Shaker has a 66-inch wheelbase compared to the Sturgis Shovel at 75 inches. As best as I could measure around the Mikuni carb, the engine is 20.5 inches wide and 22 inches tall. The front wheel is 25.5 inches in diameter. We must run Avon W or Z rated tires and so we'll run a 17 rear 140 Azaro that's 25.8 inches in diameter. The Azaro front will be an 120/18 at 24.6 inches in diameter. --Bandit

Been using this photo and others to measure from.

Just a note to let you know that I've been working hard to get the scale close. Here's my composite image that is a basis for scaling the frame dimensions (below). I rotated Valerie's arms and legs to the approximate needed position from a photo of her on the Salt Shaker and then scaled it to the engine frame reference.

There are some things to consider that we will have to discuss. Right now it looks like about 8" of stretch in the back and about 10"-12" in the front. Rough estimate for the wheel base 85"-88". Should have more to come soon.


AWscale with val

The Suspense Was Killing Us:

Here's the first real try at figuring this thing out. I worked Christmas eve till 2:45 am to get this done for you before I skip town.

A few notes:

1. Remember don't take the axle back/up and neck out/ down measurements literally as my baseline may not be the same as the frame you start from.

They just give an approximate idea of stretch. Just use the measurements from the engine mounts and the ground.

2. It will be critical to know exactly how tall your engine is to make sure you can get it in the frame.

3. Fork rake and neck rake will need careful consideration. There is zero trail as it stands which seems dangerous. The arms on the fork are probably a little too long, but it appears that if even they were shortened a bit you still won't have enough trail. You'll need to consult.

Leo on these matters. I suspect you will want more neck rake with negative rake in the forks.

4. Foot peg position is 2" back and 2" down from the axle. This can be adjusted for comfort, leg aerodynamics, or body position. These things could affect where we finalize the frames neck position also. We'll need to discuss further.

5. This is just a drawing, and I did my best to make Valerie to scale without have her here in person to measure. Will she really fit in this position and be comfortable?

6. Tire diameter for rear tire was rounded up from 25.8 " to 26" for ease of drawing at this scale.

7. Top frame tubes could use a design where they crisscross the front legs which would make for a lower backbone.

8. It would probably be best to come to my place so when we make changes we can do it on the computer or in my studio.

9. Merry Christmas


AWscale with val

The 5-Ball official Bonneville Photographer. You can buy a small book about the first Salt Shaker Effort by clicking on this banner.

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Reader Comments

Where do I find short coil over shocks for a girder front fork.

marc rowe
dover, DE
Saturday, December 1, 2012
Editor Response Hey Marc,

Check the Mudflap Girl FXR techs. Paul Cavallo at Spitfire uses two seat coil over shocks with 300 pound rated springs. They are a tad tough, so I found a Rockshox, removed the 500 lb. spring and installed the taller 300 pound job. It allowed me to re-install the shock and lower the bike if I wanted.

I was concerned about travel. The problem with Rockshox or other high dollar bike shocks is the price. I believe I also looked at Fox shocks. I wanted to run a shock with at least 2 inches of travel, which could amount to 6 inches at the axle. Sugar Bear suggested that the shock run parallel to the neck, so I repositioned the shock the last time I mounted it. It seems to work well.


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