Land Speed Racing

[HondaJohn]

Since my last update, I have gotten the bike registered and insured, and have been riding it as often as possible. It was a lot of fun dealing with the New York DMV with no pre-existing paperwork. It was so impossible that I had to go to Vermont for the initial registration (they will register vehicles for out-of-state residents), but now everything is squared away.

I've also started installing a supercharger, or rather, a roots blower meant for fish hatcheries:

http://www.ebay.com/itm/POND-AERATOR-Ro ... 45f939efbe

I haven't piped it into the intake yet, since i am running it a bit over its rated max rpm. I want to make sure it doesn't blow BEFORE i connect it, so I don't risk losing the engine in a meltdown.

[coachgeo]

love the ingenuity.... pond airator... love it.

please post up pics and details cause the ebay link will eventually NOT work so we loose all those details.

[HondaJohn]

Good point coachgeo, I didn't think of that. The "supercharger" is a Whispair 1701 Roots Blower. There are spec sheets available online. There are certainly BETTER ones out there, but this particular model was for sale on clearance at nearly 85% off the original price so...yeah, I went with that one It weighs about 19 pounds and produces a max pressure of 5 psi.

I based my calculations off the available performance curves. AT 3500 rpm, its max rated operated speed, the 296cc L70 Yanmar engine that I am using draws approximately:

296cc (x) 3500rpm (=) 1,036,000cc/min

1,036,000cc/min (/) 2 full revs per intake cycle (=) 518,000cc/min

518,000cc/min (=) 18.29CFM

I'm not entirely sure where the pressure and flow curves will normalize during the engine's operation, so I used the three available performance curves as guides.

At 1psi of boost, the pump flows at 22.5CFM. This consumes 0.3bhp to operate, and potentially increases the flow rate, and horsepower, by:
22.5 (/) 18.29 (=) 1.23 (=) 23%
This translates to a net increase of 1.2bhp, from 6.5 to 7.7. I'm sure it won't actually be that effective in the real world, but I will have to wait and see

[HondaJohn]

Here's a detail shot of the pump as it arrived:

[alexanderfoti]

Looks very interesting, I am hopefully going to be using this


Its an AMR 500. I was planning on using it with my current L100 superdream build, but im entirely sure there isnt enough space to do it (without it sticking out of the side of the engine! So I will keep it stashed away for my next build (Shame really!)

[pietenpol2002]

John,
Great to see your experimentation with blowing the little Yanclone. I'm intrigued to see what it produces. I too have one of these little Roots but the math doesn't work for my 418cc. I wonder what kind of thermal and volumetric losses you'll incur and how that will impact boost potential. Reportedly the Roots will tolerate a bit of overdrive which might be needed to overcome other losses. Might be tolerated for your WLSR runs at least. The beauty is, if ratios changes are needed it's a simple sprocket swap out. And don't forget to allow something on the order of 900cc (or is it 600cc, can't remember if it's 2 or 3 times the displacement) of plenum/accumulator - some of which would be provided by the plumbing to the engine.

[Rhynri]

This is very interesting. I am quite curious to see how this all turns out for you!

[HondaJohn]

I've finished the mounting, chain drive, and plumbing for the supercharger, and the results are very promising so far. I haven't regeared it to check the top speed, but the acceleration has seen a huge improvement. It also had the side effect of making the bike quieter by interrupting the intake noise. According to the pressure gauge I've attached, the pump produces from 1 to 3.5 psi of boost, more or less linearly as the engine speed increases. One of my local shops has a dyno in the back, so I will head over there one day soon to compare the power with and without the supercharger attached.

[alexanderfoti]

Thats Very promising! It makes me want to get rid of my fuel tank, so I have somewhere to mount my supercharger! I would drive it off the flywheel side, but the cb250 superdream is already very cramped with the engine there, not sure how much extra room there is! Shame.

Looks really good.

[HondaJohn]

Here's a quick test video of the supercharger:

http://www.youtube.com/watch?v=PJMKMuSQ ... ature=plcp

[HondaJohn]

Two weekends ago I rode my bike on a 40 mile round trip in upstate New York to test the reliability of the transmission and supercharger. I started in Troy, NY, rode down Route 2, filled up the tank with low sulfur pump diesel from a gas station in Clums Corner, NY, and marked the level with a pencil/dipstick from the filler cap. I then rode to the top of a mountain pass on Route 2 on the NY/MA border, called Petersburg Pass, an approximate elevation change of 1730 feet.

We then refilled the tank at the same gas station we left from to the original level. At an average speed of 40 mph, with a 4psi boost because of the cold weather, I averaged 95 mpg over the course of the trip.

Everything held together perfectly during the ride. There are no defects or breakages to report, except for my numb hands, which i have since cured with better hand grips. Here are some pics:

[coachgeo]

from speed records to slow down and smell the roses....... she's got it all. :d Ya sure look like ya enjoyed it. Great Pics

[Stuart]

Good stuff!

[Rhynri]

Woo!

[HondaJohn]

Had a little setback with the bike. I installed a spare valve cover on the engine, but forgot to file down the pointed casting for the PCV Valve passage. It pressed against the tank until it cracked through the sheetmetal and fuel started weeping out. On a related note, I've now learned how to silver braze

The repair is holding nicely, right in time to use it in post-hurricane New York. I think I'm the only person in my area not worried about fuel...

[HondaJohn]

I finally got the bike over to the shop for a dyno test. The results weren't as...dramatic as I had hoped, but I've got a good baseline now. The boost from the supercharger doesn't generate a significant net increase in horsepower until about 3600 rpm, which is a bit too late to do me any good. I'm going to regear the supercharger's drive chain to run it faster than engine speed, and try to shift the powerband down a bit. Here are the comparative results with and without the blower:

On the plus side, I've managed to increase the horsepower. The engine was originally rated at 6.5 hp peak at the crank, and its now topping out at 6.07 hp at the WHEEL, with a battery charging circuit and o-ring chain throughout. More updates as they come.

[HondaJohn]

Just a quick update. I regeared the supercharger with a 15:13 ratio, instead of 14:14, to increase its speed. This would shift the power curve and increase its effect on the engine. The results are:

The red line corresponds to the previous setting, and blue with the newly regeared one. I picked up 1 horsepower across nearly the whole range, and increased the peak power to 6.5 hp at the rear wheel.

[dieselbikin]

That's awesome! I didn’t notice you mentioning whether you’ve increased the fuel supply to match the increased air supply or fiddled with injector timing? Great job!

[HondaJohn]

I didn't mess with the injector timing, but I opened the injector stop WAYYY up so that the engine's governor could match the fuel to the new air supply. I'm preventing a huge cloud of black smoke out the back with careful work on the throttle, but I will start gradually turning it back down incrementally until the fuel supply and air supply are closely matched.

[dieselbikin]

The problem I used to have with my throttle setting was that if I set the fuel limiting stop for minimal smoke I lost power, but if I set it for max power I belched black smoke under heavy load. The solution was to remove the original fuel adjusting stop and replace it with a solid bolt. The original fuel adjusting stop has a spring loaded tip that allows the engine to receive extra fuel under heavy load. Some people simply lock the spring loaded tip so that it can not be pushed in.
https://www.dieselbikeforum.com/view ... =+throttle

[HondaJohn]

Its been awhile since the last post but here's an update. I've been prepping the bike for another year in Maine, and ran into some issues that needed to be addressed. As the weather got warmer, the supercharger began developing less and less boost. I was hoping I wouldn't have to spring for an intercooler, but I had to bite the bullet. I could not find any off-the-shelf models that would work, so I had a custom one made by Bell Intercoolers.

http://www.bellintercoolers.com/

Their build quality is top notch, and the prices are reasonable. Now, in hot weather the bike consistently makes 2-3 psi of boost when before it made almost none.

I also had to redesign and strengthen the sprag clutch. The most recent version lasted almost 850 miles before it wore out, so I made a new one with a thicker flange to last longer.

[alexanderfoti]

That little intercooler is awesome!

I have an air pump from a W124 that I may incoroporate into the intake, or maybe not.

[HondaJohn]

This year's land speed racing was a complete success!

I decided to go for broke, so I installed a stronger spring on the governor lever, removed the throttle and injection pump limit screws, and geared it low to take advantage of the higher engine rpm to hit my goal. I went through tech without a hitch, and my first pass topped out at 59.9mph. Respectable, but I wanted to hit 60 or higher before calling it quits. Strangely, I had seen 62mph on my speedometer during the run up to the timed section, and initially suspected a sudden headwind. However, a second run with similar results and a consistent tailwind shot down that theory.

My friends and I decided that, since I was peaking early and then slowing down, I might be heat soaking the supercharger and intercooler, thus gradually lowering my peak horsepower as the heat built up. To offset that, I installed a primary sprocket with one less tooth on the final drive to increase top end torque. My final pass after making the modifications was recorded as 60.6mph, with a calculated engine speed of 4800 rpm(!) I was worried I might wreck the engine with that speed, but I followed up that final run with a 50 mile country road ride and heard no suspicious engine noises. I suspect that that's all this bike has in it, and now may be the time to retire it from racing and start working on the next design...of course, I HAVE said that before....

[HondaJohn]

I finally got around to uploading all the pictures from this year's land speed event.

Home Base And The Team

Apparently this was a common place to find me that weekend...

Tragically, Bill Warner lost his life in a crash 3 days after this picture. His tire exploded at 290mph

Some other pictures from the event.

[HondaJohn]

I finally pulled the racer out of storage to repair the transmission damage that I found last year. I made a mistake lining up the drive chain for the supercharger, and the two sprockets were almost 1/8 inch out of alignment. After 600 miles of use, the chain was almost destroyed, and it had eaten into the drive sprocket causing extensive damage. I made a new one out of a harder grade of steel, fixed the alignment, and took it for a shakedown ride to test my new GoPro camera.

https://www.youtube.com/watch?v=Yv4iZ2n2EQQ

[coachgeo]

Looking forward to your next attempts

[HondaJohn]

My KZ400 diesel motorcycle was accepted into the Ultimate Builder Competition at the 2014 New York International Motorcycle Show. It was an incredible experience, and I was honored to share floor space with some beautifully-built custom machinery. And surprise, I didn't bring the only diesel to the show! Below are pictures of the spectacular Kubota-powered bobber that took runner-up in the Freestyle category.

[HondaJohn]

[coachgeo]

Congrads on the invite and taking advantage of the opportunity. Two diesels... coolio

[pietenpol2002]

Great work John! And thanks for championing the cause.