Going from 0 to 3D...

 The 2WS/2WD system for the next racer is assembled and on the bench! This is the first bike project of mine where the frame wasn't built first. Now the frame designs itself and gets built next. 

Cardboard aided design is too archaic - Coroplast aided design is far more advanced. First principles are all well and good - time to run with them... 

The engine is out of the donor bike. It is smaller in every dimension, 5 lbs. lighter, and over twice the horsepower of the EX500 engine in the last racer.

The engine goes up on the bench as soon as the left side gets cut down - have to make room for the front wheel drive belt. Started by milling down a gently used cover:

Speaking of engine weights, a number of engines have gone across my shop scale over the years:

Kawasaki KX500 - 60 lbs.

Kawasaki EX500 - 126 lbs.

Ducati 999S - 153 lbs.

H-D 883 4 speed - 185 lbs.

H-D 1340 Evo 5 speed - 215 lbs.

Honda CBX - 215 lbs.

KTM 890 - 121 lbs.

Getting to this point took a lot longer than expected - a combination of a serious workplace injury last summer (Off work for 4 months - they took care of me at their expense) and fading enthusiasm the rest of last year stalled progress for too long. 

 After a hard day at work, the last thing I wanted to do for fun when I got home was even more work. So why not take the night off and just crank up the Bluetooth speaker and relax out in the shop? Over There, staring me down, is the domineering markerboard. Yeah, the mill table should have been cleaned off last night - turning  the lights out on a messy mill table just isn't done. While we're at it, lets get the vise squared up and bolted down. Why not load the first part, stick the probe in the spindle, and zero out the DRO while everything is clean? Since we know where we are now, there's nothing to stop us from drilling the pilot hole. Loading the boring head in the spindle and setting the boring bit now should get the job done sooner. Hey, I'll bet that first cut will go really smooth - now's a good time to find out! The calculator says only 9.137 more passes will finish the job - the playlist on the speaker is nowhere near done and I forgot how much I liked that group - I hope the neighbors are enjoying it as well. Lets load the identical part that goes on the other end of the racer (Identical front and rear suspension has its benefits...) and give it a head start for tomorrow. Oh look - it's done already and I never noticed that the playlist must have ended a half hour ago and now the shop is deafeningly silent. On the way out the door, I get to erase that nagging line off of the markerboard and look back before turning out the lights with renewed enthusiasm. I'll clean the mill table off first thing tomorrow, after work...

One step closer answering that question "I wonder what it's like to go faster?" There's only one way to find out...

First thoughts and frequent comments....

 When the decision was made to build the last racer, the first 3 thoughts went through my head:

1. This is going to be a lot of work.
2. This is going to be a lot of fun to ride.
3. This is going to generate a lot of stupid comments.
   

1) It was. And it was worth it!
2) It was. More fun than anybody else knows!!
3) Far less than I expected in the real world - virtually none, really!!!

But then there's Facebook:

1. KANEDA!
2. That's just a copy of the Gurney Alligator!
3. You'll die if you crash or run into something!
4. All those ball joints and rods kill steering feel!
5. Can't see where you're going on the track!
   
6. Can't steer properly if you can't move your body!
7. Can't stand on the pegs while riding over bumps!
8. Why don't I see them racing in GP or the IoM TT?
9. Low CG motorcycles are hard to balance!
10. Driving a steered wheel requires negative trail! 
11. Two wheel steering is pointless and stupid!
12. It's just a two wheeled car!
13. There's no rake at the front end!

1) OK! Akira references really are fun! A friend made me really cool race team logo from "Bartkira" many years ago. The movie bike is wonderful art for fictional anime/manga, but, sadly, terrible design for the real world. But unlike too many hopelessly stalled Akira projects, my old racer was finished, tested, raced, and it worked. 

2) Considering the liquid cooled twin cylinder engine, 2 wheel steering, no steering head, virtual hub center steering front suspension, remote mount handlebar, and reclined seat and rider position, there are more differences than similarities. That said, comparisons are understandable; the 'Gator was the only recumbent motorcycle to get any decent coverage in this country from the legacy motorcycle media this century. 

3) Crashed at medium speed early 2013 - crashed at high speed later 2014 - didn't die either time, as far as I can remember. And if you are colliding with stationary objects at the track, well, you don't belong out there.

4) No, they do not. Or at least they don't if Teflon lined rod ends are kept out of the system. Even quite  a bit of play is better than a little bit of binding - the play will only be noticeable when parked - while cornering, there is a load on the handlebars (That's where feedback comes from!) taking up any play that might exist, leaving that crucial front end feel completely intact.

Front end feel comes from changes in the steering load - a little change means a lot. NOTHING kills that feel more than having the rider's weight on the handlebars while trail braking. With a recumbent motorcycle, the handlebars are just that - bars for the hands - the level of feedback from the front end is amazing if there is enough trail to provide it. Hub center steered front ends often need less trail for stability, which also makes the steering lighter, but that also reduces front end feel - something too often blamed on "All those linkages". 

Another change in perception comes from the effects of stiction - a binding telescopic fork (There is no other kind) feels rigid and "Transmits" feedback very clearly. A binding suspension also loses traction very easily. What too many perceive as "Signal" from the front end is actually "Noise". It is too easy to confuse the absence of noise with a loss of signal; the lowest level signals were lost under a high noise threshold all along. Confidence in the front end shouldn't come from noise, but apparently, it does. 

Speaking of feel: Nothing else provides a better level of feedback than a riding position that spans the wheelbase - any change in traction and/or yaw shift is immediately felt. 

No, you won't read or hear any of that from the moto-infotainment outlets. They have no experience with the subject, nor do they want any. 

5) Yes, my line of sight while riding straight and level is quite a bit lower than usual - yes, that changes one's perspective quite a bit - one gets over it very quickly with some seat time. But when leaned over, my line of sight is no lower than usual - look at how high the rider's helmet is from the track when he's dragging his elbows. If you ever need to sit up higher to see where you're going on the track, again, you don't belong out there.

6) WRONG! Calisthenics are part of the operation of current racing binary unicycles, but single track vehicles designed to use both wheels full time are steered with the handlebars. 

7) Functional suspension works better than standing on the pegs - or at least it does on paved racetracks. That reclined seat and rider position makes spinal injuries from bumps nearly impossible anyway.

8) They are cleverly banned by the ACU without overtly stating so - read "Road Racing Standing Regulations 2022", section 15.6.7 . 

The FIM rejected Morbidelli's request to race one in the Grand Prix classes.

That leaves USA club racing and track days - I'm more than happy with that.

9) Motorcycles, at operating speed, are not balanced by the rider - they don't fall down on their own. There are plenty of videos out there of riderless roadracing motorcycles rolling right along without anybody balancing them. Sure, at low speeds, such as waiting in line for tech, stopping at the grid, or heading back to your pit, the rider has to balance the bike. But at operating speed, a single track vehicle is a dynamically stabilized system, NOT an "Inverted pendulum" or static unstable object like a short broom. 

Back in 2005, I still wasn't sure that a recumbent motorcycle with a low and laid back seat would be a viable road racing vehicle - could the rider effectively operate the bike in a competitive environment? Finding the answer seemed like a wise idea before building a 2WS racer. So I modified a stand-up gas scooter and took it to the kart track in Calhan. 

Steering was perfectly calm and predictable to the point of easily dragging the seat at a 42 degree lean angle. At least a dozen others rode it - ages ranging from pre-teen to middle aged - they all had a blast on it. It would go just over 40 mph on level ground. Mission accomplished: It was restored back to its original configuration and sold so I could build a 2WS scooter based mini-moto racer. In 2006, I did - with an even lower seat:

It was even easier to steer and balance. No such thing as "Too low" for stability and control - having sufficient lean angle clearance is another matter. Try finding information, experience, test results, etc... about any of that in the OEM sales brochures, AKA "Magazines"...

10) No, it does not. A driven wheel does not behave through the trail moment arm the same way a braked wheel does. Why? Simple: The driving force is always inline with the trail moment - NO side force applied - any stabilizing side forces otherwise acting on the trail moment have the same effect regardless of the driving force. Physics says so. Testing says so. Yet the Facebook pseudointellectuals "Know" otherwise...

11) 2WS has been extensively tested here, but you'll never know it if you only read the legacy motorcycle media. The quality of the consumer comments says a lot about the quality of information they're given to consume:

MORE intellectualized ignorance about 2WS from the Facebook techno-gossipers!:

Discover something through research in the real world! Earn the sneering contempt of the foremost authority of obsolete thought! I'm sure there's a really cool meme for that, but we don't do that here...

Yes, I terminated my Facebook account back in August 2021. 

I still find a great deal of enthusiasm online from what I call the "Enthusiast Motorcycle Media" (As opposed to the "Clickbait Motorcycle Media" and "Legacy Motorcycle Media"). More about all that happy stuff was published in a fun interview at Bike-urious - thanks, Abhi!

12) OK! I'm really happy to hear it isn't just another two wheeled horseless carriage....

13) That comes up a LOT - easy to understand why - it sure looks that way! But the steering axis runs down through the upright's top ball joint (Obvious) to a virtual pivot point ahead of the front axle (Not obvious) at an 18 degree angle, with just over 4" of trail. Virtual rake, perhaps?

3rd image: Screenshot from http://npbka.com/morbidelli-project.htm

Day at the Museum...

The racer has spent almost 3 years stuck in the workshop, welcoming me every time I walked in the door. While it still is an unusually amusing sight, it isn't otherwise doing me a whole lot of good. The original plan of parking it in our living room seemed like an increasingly bad idea - a split level mid-century house, oddly enough, isn't optimized for motorsports displays. What about loaning it to a museum, so others can marvel/point and laugh at it? A call was made to That Big Motorcycle Museum in Alabama - the word "Loaning" didn't get finished before the other end of the line snapped back a snotty "We only accept donations - on OUR terms - NO LOANED MOTORCYCLES!". Oh, really: Not at my current net worth.

So the next call went out to the nearby St. Francis Motorcycle Museum. I asked if they were interested in displaying an experimental homebuilt roadracer. They said they would be interested - if it is something different. This sure sounds like the right place!

Last night, the racer was loaded up in the van and rolled in through their front door this morning. Would the spot between the ELR and unmolested R90/6 be OK? Oh, yes. 

The museum opened up in 2016 - it isn't on the usual internet lists of motorcycle museums, or at least not yet. It is run by enthusiasts - and it shows. No idea how long my old racer will be there - if all goes well, I'll retire not too many years from now and it'll end up in someone else's living room, office, or . . . museum.

In the mean time, the next racer is in that stage where lots of work has been done, but it doesn't look that way - just an increasing spread of small parts waiting to become one big part. Boring, indeed. 

That's one of the wheel uprights - one of two welded assemblies of 6 machined 4130 tubes each that gets finish machined after welding. It is far more work than the similar bolted-up solid aluminum one at the back of the last racer, but the new ones weigh less than half and look a lot better (Yes, that matters!). A fiber wound forging would look even better and weigh even less - not happening with the resources at hand. The last racer's rolling chassis assembly weighed 290 lbs - if the next one can get down to 190 lbs, we'll be in great shape. 

One Step Forward, Two Steps Sideways...

One of the big challenges for the next racer was building an engine with my own crankcase. The built and fully developed engine was expected to weigh under 100 lbs and produce over 100 hp. The initial engine build is the relatively quick, cheap, and easy part - the development is where time, money, and work can be severely challenging. All of that isn't entirely necessary any more - the recent KTM 890 engine fills that requirement reasonably well. A KTM Duke 890 has just rolled in the shop, and a lot of the previous donor engines and parts have been sold to help pay for it. This project was about a year behind schedule - this moves things forward quite a bit! Absolutely no changes are required for the rest of the motorcycle. A 4-stroke twin also provides greater opportunities for racing in clubs that accommodate real purpose-built race bikes. 

Unlike the EX500 engine in the last racer, the 890 engine has a very advanced ECU. A lot of learning and work lies ahead getting that to work in a racing application with different dynamics and no ABS. At this point, I don't know how well the stock ECU will work with the next racer. Or if it'll need a race ECU, like the one on the just released KTM RC 8C. Should know a bit more about the subject when this is done...

Building and running the 2-stroke engine design that I had in mind would have made for a good story. While lap times and all that don't care about "The Story", the most intriguing racing motorcycles have a good story behind them beyond the race results. I don't believe that racing is strictly about the racer and not the motorcycle, otherwise we could just discard those unnecessary machines and just race unburdened the purest way imaginable: Running barefoot and naked! No, that's really not my idea of fun, either. But a finished story is always better than an unfinished one - right now, the 890 engine is the fastest and easiest way to get the happy ending I'm expecting.

That 2-stoke engine concept is still worth pursuing later: Modern casting methods could result in a far lighter engine than any backyard foundry can render. A simple, cheap, and easy to work on engine with over 100 hp but under 50 lbs will take a real design and development team and facility - it certainly won't be one man's story - same thing with an under 150 lb pivotless carbon rolling chassis for said engine. Won't happen 'til the current project generates some real results and excitement. Motivation, enthusiasm, and all that happy stuff.... 

In the mean time, work is still in progress. Ever wonder what a 2WD motorcycle differential looks like? The inner (Rear wheel) pulley is solidly mounted to the spool - the outer (Front wheel) pulley is mounted to the spool with a one way clutch bearing. The spool itself mounts in the drive arm and is chain driven by the engine.

Before tearing down the KTM, it'll require some break-in mileage. It is the first "Normal" motorcycle I've ridden since race school, early 2012. It seems like a shame to take apart a perfectly good bike (And I really like the Duke 890 an awful lot!), but the next racer should be faster, more fun, and have a pretty good story behind it when it is done...

...But Why....?

According to the social media techno-gossipers, I'm doing everything wrong! They don't know what I'm doing, so clearly I must not know what I'm doing...

Roadracing motorcycle design has evolved itself into a dead end - they can't accelerate or decelerate any harder without flipping, or corner any harder without running out of clearance. Any changes to one or more areas to improve one aspect will result in an overall loss of performance. Tires are optimized to accelerate or brake, not both, leading to cooling/overheating events. Suspension has to be optimized for load transfer extremes. All the above leads to both slow roll response and high polar inertia about the roll axis. And that results in terrible aerodynamics. ALL of the above problems can be successfully addressed IF you discard the old configuration and derive a functionally superior new configuration.

Here are those problems (And causes):

1. Stoppies (High CG, short WB) 
2. Wheelies (High CG, short WB) 
3. Lean angle limitations (Oversized rear tires)
4. Roll rate limitations (High roll axis, high polar moment)
5. Suspension sub-optimization (High CG, short WB) 
6. Tire sub-optimization (High CG, short WB)
7. Aerodynamic sub-optimization (High CG, short WB)

And here are the solutions:

1. Long WB, low CG, linked brakes
2. Long WB, low CG, 2WD
3. 2WS, appropriate tire selection
4. 2WS, low roll axis, low CG
5. Long WB, low CG
6. 2WD, 2WS, linked brakes, long WB
7. Long WB, low CG 

And here's the how, why, and all that:

1. Pretty obvious, really. If load transfer under braking can't flip the bike, then there must still be some load on both tires. The lower the CG, the less load transfer, and the more both wheels will do the work. It also means that trail braking will be a lot more effective as the tire's loads transfer from braking to cornering.

2. Also pretty obvious. Same as the above, but from the opposite direction - just a lot more difficult to implement. Doing it beats complaining about it. The ultimate solution to that problem is addressed near the end of this post.

3. Not obvious, at least with the 2WS part. The tire part ought to be obvious: With 2WD and linked brakes, a big fat rear tire is no longer necessary or even desirable. A narrow tire at both ends provides enough footprint area - more about that in #6, below.

With 2WS, cornering force deviates from perpendicular to the roll axis, thus reducing lean angle (Simple trigonometry, if you must). If 2WS is taken to an extreme, a single track vehicle dynamically transforms into a purely 2-tracked vehicle known as a "Di-cycle": NO lean angle required at all for cornering. That isn't practical for obvious reasons, but steering the rear wheel in the same direction of the turn at any proportion much over 25% (Ideally over 33%) contributes to the same effect, thus significantly reducing lean angle. 

Both the narrower rear tire and 2WS effects greatly offset the negative effects of lower CG on lean angle. No, this isn't in any of the books. Yet. 

4. Not as obvious as it ought to be, sort of: Obviously, the reduced polar moment makes changing lean angle easier and also importantly, makes stopping changes to the lean angle easier. Less obviously, the lower the roll axis, the greater the lean angle changes with displacement of the contact patch relative to the roll axis when countersteering. 2WS normally wouldn't help at all with a high roll axis in that regard, since most of the effort in countersteering is exerted in overcoming wheel inertia - but with the lower roll axis and that increased displacement effect, countersteering becomes a LOT faster with the same effort.

5. Extreme load transfer is no longer happening, which means that a suspension range and rate to accommodate those extremes is no longer required. And with less suspension travel comes less sag under cornering, thus improving ground clearance and increasing potential lean angle even more. Lower CG and long WB, and less travel also means drastically reduced chassis pitching to bump response, acceleration, and braking, resulting in far greater chassis stability. Steering geometry can be optimized full time. And greater chassis stability reduces the appeal of conjuring pro/anti(Fill in the blank) magic geometry, thus making that pursuit irrelevant.

6. With 2WD, linked brakes, 2WS, low CG, and long WB, both tires are working all the time - a relatively constant load should result in a relatively constant tire temperature - tire cooling/overheating shouldn't be such a major source of drama anymore. And since extreme load transfer isn't happening anymore, much lower tire pressures (With the obvious benefit of a larger footprint) are both possible and desirable without developing stability and control issues. Having interchangeable front and rear wheels and tires is a welcome benefit. I doubt that existing tires are close to optimized for such implementation, but the choice of racing slick tires with different compounds and carcass stiffness is a huge help.

7. Brutally obvious: Much lower frontal area results in much less drag. Like totally free horsepower, man. Really. No kidding. 

The rationale (And obvious physics) behind all 7 points guided the design of my next racer. All 7 points are necessary, however inconvenient, to work. No, I don't expect said techno-gossipers to grasp any/all of those points. Nothing in the real world depends on their comprehension or consent. 

Yeah, OK, so what else is it good for? Well, electric motorcycles exhibit a LOT of functional shortcomings relative to their internal combustion relatives. Horseless carriages were usually terrible cars - gasless motorbikes are usually terrible motorcycles. But a lightweight streamlined low CG, 2WS, 2WD electric street motorcycle would solve range, speed, cost, packaging, and weight issues while providing uncommonly high comfort, performance and protection right now. Electric 2WD almost designs itself. Truly effective regenerative braking is only possible with 2WD, low CG, and long WB. With 2WS and 2WD - and smart steering control - it would be possible at a stop to steer both wheels to the side to some degree and balance the bike without human intervention - no dippy outriggers or ludicrous gyroscope system necessary. A minimum turn radius of half the wheelbase would make it far more maneuverable. Then park it by lowering it all the way onto an integrated stand. Wind gust response would be counteracted by that smart 2WS. Smart 2WS (Or even active steering dampers) would also allow the use of tires optimized for traction rather than ease of steering. And so on and so forth - the design and dynamic potential is mind-blowing - something far beyond my next internal combustion powered racer. None of that is in the motorcycle advertorials.  Yet.

January 2023 Update: Over a year after the above was written, many of the above points were made in a FortNine video about "Feet Forward" motorcycles. No, none of my work is featured, but it is still a fun video.

In the mean time, work is progressing nicely if not quickly on the next racer. 

Oh yes - MRA race video was shot one day only in the abbreviated 2020 racing season. There was no awards banquet, which meant nobody produced an awards banquet video. So I compiled my better video clips - no effects or soundtrack - just racing: 

That video camera was sold soon afterwards - need to focus more on building the next racer....

Here we go again...

In addition to design work and parts acquisition, the last two years were spent getting the new shop set up and tooled up. The shop is ready to go now -  work is in progress on the new racer! The first steps were making a face plate fixture for the wheels and boring the wheel hubs. Then the split hub center steering hubs get machined and installed in the wheel bores. After that, all that's left to do is everything else. It is going to be a lot of work and take a lot of time - can't think of anything else better to do. This is also going to be an awful lot of fun...

Hunting and Gathering...

All of this year's track time was spent behind the viewfinder shooting with a new JVC GY-HM620. A lot of my clips made it into this year's MRA Awards Banquet video. Already looking forward to wandering around and shooting at HPR next year!

After the Quail event, Jason Cormier at Odd Bike asked me for an article on the racer project and some of the background - that gave me a good excuse to explain a little how I got to this point and a little more about where I'm going. It's been a fun experience so far, which made it a lot of fun to write. Thanks, Jason!

All of the custom ordered parts have arrived: Connecting rods, crank pin, and hybrid Kawasaki KX500/Ducati 999 primary gear (All from England), Poly Chain GT 8 mm pulley stock (For final drive), and 56 mm Lectron downdraft carburetor (For feeding 706 cc crankcase displacement). And then there's the one and only part I just pulled off the last racer that goes on the next one - it's a part that's getting a lot harder to find.

The engine casting will have to work well with the 2WD final drive arm, so those get designed and built together - after that, the frame and 2WS system pretty much fall into place. The big plan for the bodywork is to have as little as possible, as simple as possible, and as cheap and easy to replace, vinyl wrap, and install as possible - wasting time and money on dysfunctional over-styled plastic that gets vinyl wrapped anyway seems really stupid on a racer, where bodywork is considered a consumable item, like tires, safety wire, cash, collarbones, etc...

So where does a home built supercharged single cylinder 2 stroke 2WS 2WD motorcycle race? Obviously not any of the "Professional" OEM-centric racing organizations. The local club's rulebook is very helpful - since I'm making my own racer, the supercharger isn't aftermarket:

And then there are always those therapeutic track days....

But there's many years of work left to be done in the shop. Thankfully, it now has something every race shop needs: Lots of hot air!

A Retirement Party....

A few months ago, I read an article on the Quail Motorcycle Gathering show for this year. Well, the old racer was never built for show (And never entered in one, either), but it sure is a great conversation piece. So a show application was submitted - and it was accepted! The 2014 crash damage repairs have been finished and painted. Seven years worth of neglected and ignored cosmetic flaws have been mostly fixed. The battery and some fuel are back in it - it'll get fired up and ridden a little one last time before it gets retired. It sometimes seems like a waste just to park it when it is so much fun to ride, but that would be time and money from the next one, not to mention the possibility of getting too enthusiastic and crashing the old one again.

19 May update:

The racer was loaded in a van and driven about 1400 miles to the show. The weather was perfect, the guests were a lot of fun, and the judges were very enthusiastic. No trophy this time, either, but the experience was priceless - there's no better show in the USA. After the show ended and the field cleared out a bit, the racer was fired up and ridden back to the van. That was a short, slow, yet very satisfying final ride.

The racer also received very enthusiastic media coverage by Julia LaPalme from Motorcyclist Magazine, and Abhi Eswarappa from Bike-urious !

And that's the end of that project - on with the next one.

Last photo: Michael Moore

What's Next...

The final race of 2018 was the first and only weekend out for the racer. Bad weather resulted in no practice. The racer behaved very well, but that lack of practice resulted in really awful lap times. Many of the other racers ahead of me were battling for season championships - I didn't think that one person's proof of concept development program should interfere with the sporting intentions of the other racers, so I pitted before I got lapped. One racer followed me from the start - after I pulled off, his lap times dropped a lot - I hope he enjoyed the show. Unless someone else needs to test the racer, that's the last time I take it to the track. From now on, I'll get a kick out of looking at it in the shop until it makes it upstairs into my living room/office.

My favorite thrill is pinning the throttle after the apex of T3 at HPR, especially with an untested bike. My second favorite thrill is getting an idea out of my head and turning it into a design before making it real, loading it into the van, and taking it to the track. The next racer is into that "Second favorite" stage. The details are a lot different than the first racer, with a few exceptions. The shocks will end up in the same area, and the upper A-arms and single sided steered upright will return at both ends (With vastly lighter and better looking design and fabrication). I'm really excited about the design of the lower suspension arm - it is VERY exotic and unique (One arm for both wheels) - it solves all of my prior 2WS/2WD design nuisances and headaches.

Another good thrill is having a photo pass for MRA events and shooting video. While nothing beats the view of the race from a race bike, being able to wander around the track and scout out vantage points for capturing the action is about as close as anyone else can get. A lot of my footage made it into the MRA's Award Banquet video - thanks for the credit!

Getting the shop together and tooled up is still in progress. All of the lighting and outlets were removed and replaced. A heater should be installed very soon. Real machine tools have been moved in. As always, good help is necessary for rigging heavy machines!

There's a LOT of work in the shop to be done in 2019. And MRA racing action to shoot at HPR with a new camera this upcoming season well.

T3 awaits...

Top video: Jeremy Alexander