We are close to finalizing the design of the Flying Dragon landspeed motorcycle! We had to switch our class from A-BG-100 to a fuel class due to issues with the turbo that was donated to us, and we are now planning to run nitrous to gain the required boost in horsepower. Below are a few pictures of how the motorcycle’s looking in ProE!
One of the major issues we’ve begun to debate recently is running a classic rear suspension or a hard tail. Both have their advantages. A classic suspension ensures that the rider will maintain control, keep the back wheel on the ground, and cushion the rider on almost any terrain. That’s why almost every street-legal motorcycle you see will have some form of rear suspension. However, our motorcycle is being purpose-built to run on the salt flats – quite a bit different from your standard highway.
While we know the terrain at the Bonneville salt flats is extremely flat, the actual properties of the ground can vary from day to day – and even at different locations along the track. If we show up at speed week and it’s rained in the past week, the flats will likely be softer and more sand-like. If it’s been dry for a month, we can count on the majority of the track being hard. However, it’s been noted in a number of books that even in dry weather, the texture of the track can change multiple times along the length. If it’s soft, those who run before us might alter the texture of the track and increase the number of bumps we encounter.
At the moment, we’re looking into running a hard-tail mainly to simplify the design, greatly reduce weight, and reduce points of failure. However, if we get out to the salt flats and the terrain isn’t as forgiving as we’d like, it could be one bumpy experience for our rider.
Most of the team is back from the holiday break and working on the project.
We got our new radiator in. It’s a 7-row universal oil cooler that we’ll be using to replace the original KX100 radiator. It is slightly longer, but it’s thinner, doesn’t look like it got hit by a train, and much cheaper than a replacement of the stock radiator. Below is a comparison picture.
Since we were unable to get the specs for the entire transmission (we were missing the tooth count on the clutch and the manufacturer was not being helpful), Dave pulled off the housing. Check out a few of the pictures he took. (Not pictured: When he took off the housing and forgot the chamber was filled with fluid, thus soaking the workbench. Whoops.)
We spent all day today working on wind tunnel testing scaled down examples of the Dirt Bike and an example of a proposed frame concept. We were attempting to determine changes in drag coefficient and cross-sectional area from one configuration to another. We did four sets of tests at wind speeds ranging from 12 m/s to 22+ m/s: The dirt bike, the concept, the dirt bike with a rider, and the concept with a rider.
A quick summary of results: It appears the drag coefficient on the modified bike turned out significantly higher than that of the dirt bike. While this is somewhat of a disappointing result, the way in which the modified bike was constructed left a lot of places for air to catch (Lots of ridges from electrical tape, etc). However, the cross sectional area was nearly 1/3 that of the original configuration, and thus the overall drag force experienced by the rider and motorcycle was significantly reduced. In future scale tests, and certainly the final construction, we hope to achieve an overall decrease in both cross-sectional area and drag-coefficient, as well as improve the experimental setup. Also note that many of the lower-velocity coefficients of drag are not very reliable since there was a decent amount of friction to overcome in the test setup.
Special thanks to the Drexel MEM Lab Manager, Brandon Terranova, for letting us tear apart his wind tunnel configuration to do our testing.
Check out a bunch of pictures below! (Apologies for the quality – we forgot our good camera)
Full Steam Ahead!!
Posted: December 12, 2011 in UncategorizedTags: hot rod products, millennium technologies
So finals are over and Christmas break is here….but not for us. Today has started a busy next couple of weeks for us. We scheduled to get all of over design into CAD models to get a prototype model of the bike. We have been very lucky and picked a good amount of engine part sponsors. Right now we are all in the lab working steady on design. I am working on reverse engineering our engine into CAD today so once the frame is mocked up we can make sure we have good clearance and fit. We have a lot of engine parts coming in now its like christmas time for the group. We are rebuilding the engine and replace most of the internal parts with forged material. We will stay up to date with our progress through out the week as we design more and more.
Now to talk about some of our sponsor that we would not be able to do anything without them
Millennium Technologies website
Millennium Technologies jumped on board with us and gave us a sponsorship to do all the cylinder work we need done. These guys provide repair and maintenance services for cylinders and cylinder heads, and manufactures nickel silicon carbide plated cylinders for a variety of engines, including motorcycles, snowmobiles, race cars, karts, dirt bikes, watercraft and aircraft. They use a Nickel Silicon Carbide Composite Coating to but a hard and durable surface on the cylinder walls. We sent out cylinder out and got in back in no time looking brand new and amazing.
Wiseco Performance Products website
Wiseco makes almost every part for the engine and are a great company to deal with. Wiseco was very generous to us and supplied with a sponsorship consisting of 2 forged piston kits which include the piston, piston rings, wrist pin, wrist pin bearing, wrist pin retaining clip and top end gaskets. They also are supplying us with a bottom end gasket kit.
Hot Rod Products website
Hot Rods makes great cranks and rods. These items can be bought pre-assembled and ready to rock. Hot Rods has supplied us with a 60% off sponsorship. We have purchased a new crankshaft and forged connecting rod from them. Along with new crank bearings and main oil seals.
Innovative Motorcycle Research website
IMR is owned and operated by Rich Cronrath out of LAC Township NJ. IMR is the east coast Pirelli motorcycle tire distributor. He is very involved and very knowledgeable when it comes to motorcycle racing and engines in general. Rich has a great shop with an amazing dyno that we will be able to test on. He also is providing us with his expert opinions that can only be found through experience. Rich is a real stand up guy and has supplied us with a small turbocharger that might be perfect for our bike.
Keep your eyes peeled for more future updates
-Dave
With the proposal submitted to Drexel and the Thanksgiving Holiday done with, we’re finally able to get back to working on the project. A lot has been going on behind the scenes. Dave has been in contact with a few companies obtaining sponsorships for engine parts, the major dimensions of the motorcycle are almost finalized, and the requirements of each of the components (Requirements for the solenoid shifter, coolant tanks, and turbo). We’ll have more on that when it becomes interesting to post about.
However, we did obtain a Turbocharger, donated by Rich at Innovative Motorcycle Research, which Dave is in the process of verifying can be used with our engine. It comes off of a BMW 335i twin-turbo.
The whole group has recently been very busy with midterms, and unfortunately we have our official project proposal due to the Drexel MEM department in less than two weeks. The project itself is somewhat concentrated on “non-exciting” things at the moment. Once the project proposal is in, the system and detail design phase of the project will begin and we’ll start to have updates and drawings on specific parts of the bike.
In other news, we began tearing down the damaged SV650 we bought in an attempt to get some funding. A picture is below.
Among our list of challenges to qualify for the “A-BG-100” class is supercharging or turbocharging the engine (henceforth referred to as “supercharging” unless specifically noted). While fuel-to-air mixture control, thermal and mechanical stress on the engine, and a higher cooling requirement are problems that must be considered when supercharging any engine, the act of increasing inlet pressure (in any useful manner) itself is particularly difficult in a 2-stroke. The main issue is simply that, during the cycle, at any given time when the inlet is open, the exhaust is also open. This would result in the fuel-air mixture being (at least partially) blown straight out of the exhaust. (This issue and its solutions will be discussed more in depth in a later post).
So the natural question is then: “Why use a two-stroke if a four-stroke qualifies for the same class?”. It’s simply an issue of power density. In a given engine, it’s simple to see that a larger displacement results in more power: The larger the volume the piston is able to sweep, the more fuel-air can be ignited per rotation of the engine, allowing greater energy transfer from the combusting gas to the piston/crankshaft, generating a higher amount of power. However, in our case, the variable of displacement is set (100cc). Thus, we must maximize the power we can get from 100cc displacement.
In a four-stroke engine, a mixture of fuel and air is ignited once every four strokes (with a stroke being one motion of the piston up or down the cylinder). This allows for separate stages of fuel-air inlet and exhaust, which has a number of advantages (mostly due to fuel economy, pollution reduction, exhaust control, and power variation over a range of RPMs). However, the piston has to traverse the cylinder four times for every time fuel is ignited to provide energy. This means that, given an engine running at 8,000 RPM, it’s only receiving a fresh dose of fuel 4000 times per minute.
In a two-stroke engine, a mixture of fuel and air is ignited once every two strokes. This means that, given 8,000 RPM, the engine is receiving a dose of fuel (and, therefore, energy) 8,000 times per minute. This results in the thermodynamic cycle occurring at twice the rate, resulting in a higher output of power from the engine at a given rotational speed.
So for a given engine size, someone competing with a two-stroke engine has theoretically *twice* the potential power than someone with a four stroke. That’s an advantage we’d be insane not to take. (Note that a two-stroke will normally not actually get twice the power of a four stroke due to imperfections in the cycle. Exhaust control and its importance to total power will also be discussed in a later post).
Obviously a four-stroke with a well-implemented supercharger has the potential to outperform a two-stroke with a badly implemented one – and in reality, that’s one place where we have to get it right.
We’re still heavily into the concept generation and selection phase of the design. We were debating for hours on what kind of suspension we should try to implement and realized reassembling the frame and suspension of the KX100 might help us visualize our ideas. It only took about 10 minutes once we figured out part of the swing arm was on backward. Below are a few pictures!
theflyingdragon 