Every Week?

I've been meaning to write something and I realize it has been over a week. Every time I start I realize that I want to add pictures to help tell the story better. I want to finish the with the gears but need to get a few images together. Sorry for the delay. I really haven't forgotten, and things are moving along again. Please stand by.

Currently Residing in the Where Are They Now File.

Currently residing in the where are they now file.

I Have a embarrassingly dusty collections of parts laying around my shop. there are everything from BMW Transmissions and final drive parts to smart engine bits and various sport bike shocks. As well as gears and intermediate shafts from bikes of various styles and from various manufacturers. All of this is kind of where I left off. I never really stopped though construction kind of ground to a halt since about September 2013. After I got the frame Mocked u and the DiFazio hub Center parts all finished I turned to mounting the engine and ran into a problem. The first problem was that I had start fabrication before I finished designing and I really should have known better. I was anxious to start making parts and got enough on paper that I thought that what was left was relatively simple and essentially detail work. Of course one mistake in placing the engine in the original design and the one in the front suspension compounded to create a few fairly big challenges. More important and even more fundamental was how to solve the problem of gearing. This I was planning to solve concurrently with designing the frame etc. However it turned out, that when I got caught up in over thinking the solution to the gearing problem, and then when the events of the last few years forced me to put life on hold the resultant mess caused a huge psychological barrier that kept making me procrastinate the restart (?) of this project.

                The problem with the gearing is this: The CDI engine being a Diesel was designed to rev no more than 4.5K rpm. This is the practical speed limit of most Diesel engines and is limited by the speed at which flame cam propagate thought the compresses air fuel mixture in the cylinder. Diesel oil just doesn't burn fast enough to spin the engine any faster. The next issue is that most motorcycle transmissions are designed for engines that operate at least 2 times faster than the practical operation of the smart and are therefore geared much lower than I need for my application. these transmissions are also designed for a top speed that is again well below what I'm shooting for. Normally on a chain driven bike I could change the ratio of the front and rear sprockets, but even then with the existing transmission gear ratios I have to work with I would have had to over drive the final drive to even get close to where I wanted to be. To get the speeds I'm looking for, the front sprocket would have to be so large that I would have to drastically modify the transmission case and would still have trouble fitting it with the rear suspension. This lead me to explore two ideas. the first was to build a rear final drive like the one BMW uses but with my own gear rations. Having a custom set of bevel gears wasn't really an option so I tried to find existing gear pairs that were reasonable priced, designed to handle the power of an engine my size and lastly to give me a ration that would give me the speeds I was hoping to achieve. What made this a bit more difficult was that most manufacturers publish the gear ratios of their transmissions but often leave out the primary input ration which is crucial to calculation the rear wheel speed for any given engine rpm. I was forced to actually open one of my transmissions up and count the teeth on all the gears in order to put together an accurate spread sheet together of all 6 gear sets and the primary input ratio. In case you are wondering, The primary input ratio on these BMW transmissions is 1.8. Meaning the engines rotational speed is reduced by ~55% going into the transmission. Since the Primary gears and I have no experience with designing gears I dismissed the idea if changing the primary gears to get a ratio that worked. the next Idea was to build my own final bevel drive. replacing the BMW unit which on the R1150Rt had a ratio of 33:11. Making the spindle and the housing wasn't particularly daunting, I just need a gear set that again had a ratio that worked for me. Most Japanese shaft drive bikes use engines with a horizontally or transversally oriented crank. This requires what they call a middle drive gear on the output of the transmission to change the drive line direction 90deg to accommodate the drive shaft. These middle drive gears are usually found in ratios relatively close to 1:1.2, are easily able to handle 100hp or more and best of all are super cheap used on EBay. I was able to get a number of sets from different bikes like the Kawasaki ZG1200, Vstar 1500, Yamaha XS1100. Each gear set was bout $35 with the gear box and it allowed me to choice of similar ratios. After settling on the Kawasaki ZG gear set I designed a new gear box and spindle that allowed me to use the BMW rear wheel and also keep the BMW single sided swing arm configuration.  What I wound up with was buildable but wasn't ideal. The most nagging issue to me was what if the gear ratios didn't work out once I actually got out on the salt?. What If I got out to Bonneville and found out that the rear drive was either over geared or under geared for what the engine power, salt conditions etc turned out to be in actuality? Choosing to solve the gearing problem with a new final drive pretty much locked me in to one gear ratio. To change it would require finding a new gear set and completely designing and building a spindle and housing to fit. From there I played with the idea of creating an intermediate drive to convert the longitudinal output of the BMW transmission to a transverse shaft. Something that would allow me to run a chain final drive and from there vary the final ratio as needed by changing the sprockets. The problem was now one of having a front sprocket that was too big to be practical. Even though there are front sprockets made for Iron head sportsters that are as big as 26-28 teeth these would be difficult to fit without having t cut away a large part of the transmission case (which I was still planning on using as a swing arm mount like the BMW's) or fit the intermediate shaft assembly completely behind the transmission thus extending the wheelbase about another 15" from what the frame was already designed to be. There are a couple of examples of people who have made similar setups on both BMW's and Moto Guzzi's but with two major points. first is that the gearing they needed was very close to what a typical street bike would need so the size of the front sprocket was more or less "normal". The second was that these intermediate setups didn't work very well under high stress. Even for normal street use they had problems. It was also another layer of complication that I really didn't want to add.

This problem vexed me for much of the last two years the project was dormant. Eventually I decided that I had to start working again on the bike and that starting to do anything, even if I would up changing it later was important just to get the ball rolling again, so I tackled the gearing question again. This time in earnest and with a resolution that whatever I decided, I would build it, move on and worry later if it was the right solution. Luckily Chris convinced me to have another look at changing the primary input ratio of the transmission. Again, I had no practical experience with engineering gears but after some simple explanation and reassurance from Chris it didn't seem insurmountable. This of course would be the simplest solution by far if it could be done. I have three BMW R1150 transmission I have gotten on EBay over the last few years so I took the one that had the highest miles and the most knackered input splines (a common problem on these transmissions) and took it apart again (I had had it open once to count the teeth to confirm the actual gear ratios inside the box. As it turns out changing the primary ratio is very simple in theory. The R1150 transmission has three shafts in it. The primary input shaft which only has one gear on it. the intermediate shaft which has seven (the mating primary gear and half of the numbered gear sets. And finally the output shaft that has the other half of the number geared sets or 6 gears. The input and output shafts are serviceable items according to BMW and the gears are held on the shaft with retaining clips at one end of each shaft. These are pretty easy to disassemble and reassemble. However the intermediate shaft is never meant to be serviced. BMW considers it a monolithic part and if it is ever damaged or worn, BMW requires you to replace the entire shaft with gears. This is because of the way the shaft is assembled. The shaft and 6th gear (which is one of the outermost gears) are machined as one piece. All the other gears slide on to the shaft with some fixed to the shaft with splines. The last two gears at the opposite end of the shaft from 6th are pressed permanently on to the shaft thus capturing all of the other gears. As it turns out the two pressed on gears are 2nd and the driven primary gear. In order for gears to be pressed on to a shaft with no splines or no keys and be expected to never move, even over thousands of miles and under the torque of a 11500cc twin, the interference fit between the gear bore and shaft must be serious. This would also require a massive amount or pressure to get the gears assembled. I was hesitant about trying to get the intermediate shaft apart but Chris didn't think it was that big of a deal. We have a 25ton press at the shop so I plasma cut a split fixture plate out of 1/4" steel and we put the shaft in the press. 

It took a lot of force. The pump handle to the 25ton hydraulic cylinder could practically hold my entire wait off the ground before the pressed on gears finally let go. it made a very loud bang but we got them off. Once off I mic'd the shafts and the bore diameters and drew new gears with the help of a gear generator in Solidworks. I'll pick up with those details and my trip to State Tool and Gear in the next episode. Stay Tuned!

The Input shaft (Left) and the Intermediate shaft

The Stock Primary Input Gears

New Post Every Week?

Part of the reason I'm posting to this blog is to tell this story for my own understanding. I'm going to not only document the building but try to include more of the overall details as well as some of the color to try to give a more complete picture. I want to try to do a where we left off post and then a where am I now entry but I don't have the pictures for the later yet so I will try to do that those in the next post or two. In the mean time I realized that I didn't post anything about 2014 which was the last time I was out on the salt. There really isn't much to tell as it was very wet. It had rained over the summer and the water that renews the salt in the spring hadn't evaporated and so things were a mess. we were allowed out and there was a course set up but the pits were wet and a mess and progress for most was slow if non existent. However, It was amazingly beautiful. Even more so than it normalcy is, with some of the most spectacular mornings and evenings anywhere ever! I am loathe to invoke the Divine, but this if anything was the hand of god. The pictures don't do the spectacular beauty justice, but here they are, and I hope they speak for them selves.

The more you pull up, The less lift you get.

I know!! it's been a long time, right??

If I had to sum up a Bonneville land speed effort perhaps the most fitting way I can come up with, is overcoming drag. Think about it. In even the darkest most insignificant corners of a project like this you can find drag. Before you ever get a vehicle to a track, think of all the problems (drag) you have to overcome. Please forgive me  for the forth coming onslaught of aerodynamic analogies, but in a lot of way they are apt. The project is the process that starts at the very beginning. From the first moment, when the first idea of running something at Bonneville pops into someones mind. The "I want to set a land speed record" laps of better judgment. The moment when, despite years of responsible, adult, mature thought, our inner 16 year old decides that jumping into the river from the train trestle is not only a good idea, but something we really have to do. If sense or self preservation doesn't kick in, the project starts there. A massive vortex of ideas and aspirations. Not a lot of drag at this point due to the slow speed but the flow sure isn't smooth.As it continues and the ideas are streamlined from the chaotic turbulent mass to a smoother more cohesive flow, progress hopefully continues. Though turbulence and drag are never completely eliminated, the further things progress the smoother things hopefully get. I also would hesitate to say that in my case a project never actually sees a planned conclusion. In my experience, even though there are set goals, once that goal is reached the goal posts are almost always moved. In other words, my projects almost never end (although they sometimes they do die). So, from concept, to design and construction, to testing and reiteration or refinement, and all the way up to and including fielding the vehicle,that is just the beginning. The project usually continues from there to further refinement or additional iterations with the goal of better the achievements. I see the Project as the administrative or executive or overall envelope of the effort. Where am I going with all this? Despite appearances, this project has never died. Though there has been some very significant drag in the way of construction, I have nonetheless been designing, researching and planning for the last 3 years. I'll try to start paying more attention to this blog and bring it up to speed by posting a couple of entries about what I have done in the intervening time and where things stand now. I'm hoping that if I set a goal of posting here once a week, it will not only keep interest high, but also motivate me to continue to push forward and to document what I'm doing. Stay tuned.

New Post Every Week?

Report From Bonneville (Way Late)

Bonneville 2013

Let me say for the record that I hate writing. Even the necessary emails that I have to do on a daily basis are often arduous for me. That said I do feel like I have a lot I want to share and that I’m way behind so let me try to catch up a bit here. First Scott Kolb has resurrected his long dormant blog about the 125cc partial Streamliner. Go read it. it has a lot more pictures of the fabrication than I will post here and Scott's description of the process is a great way to get an understanding of just what went into building his bike and you can read about the full streamliner he has in the works. His bike has been the inspiration for my bike he first built it and went to Bonneville in 2006. It is his bike you see in these pictures and it is Team Kolb that is the team I've gone to Bonneville to support (2010 and 2013). Since 2010 Scott has held the record for the Special construction (frame) Partial Streamline (body), normally aspirated, Fuel 125cc. Since 2010 Hence the markings on the side 125cc APS-AF. That record was 146.72mph and still stands. Prior to that he has held 125cc records since he first set foot on the salt in 2006. In February of 2011 we got the chance to do wind tunnel testing at one of the A2 wind tunnels in Mooresville NC.

Also setting the record for worlds
 most meticulously applied graphics!

Scott, Andrew and I go over the
 Sponsorship Graphics

That was an incredibly educational experience and provided a huge amount of data that we used to make improvements to the aerodynamics of the bike. We weren't able to make it to Bonneville in 2012 for financial reasons but this year we did make it due to a large part Scott’s determination and a most of the expense coming from Scott personally. With the improved bodywork and a new motor we were hoping to significantly increase our record. Scott decided to run in the AG class this year as the record in that class was significantly lower than our previous speeds so it was an easy target relatively speaking.

The only person at the event
lighter than Scott,
Aden tries on the bike for size.

Tech Inspection is a game
 of"What will they object
 to next and why
 they are wrong".

 Our real goal was to have the updated bike see the kind of speeds we calculated it should be going (we believe 170mph+) which was significantly faster than what we were running in 2010. In 2010 we felt like the bike never reached its potential mostly due to traction issues but the improved aerodynamics we hoped would help with that.  Unfortunately this year the bike arrived at Bonneville bit under prepared and so quite a bit of time was spent during the first days getting the bike ready for tech. 

At the starting line wait for our turn.
 The People who volunteer at the
 event are always great to talk to
while waiting

When we finally got through tech after fixing a couple of objections from the inspectors there were only 2 days left to racing. We had some electrical issues that showed up at the worst possible times limiting the number of runs we ultimately got to do but all in all it was a success and Scott set a new record in the 125cc APS-AG Class (spec Fuel) of 149.907mph.  

Also along for the ride this year was a film crew directed by noted photographer Jason Brownrigg. you can see he and his crew in some of these pictures. Jason is filming for a pilot for a TV show he's pitching that will showcase various american motor sports and their participants. You can check out the segment on Scott and the Bonneville effort here: http://vimeo.com/69919930

Launch!

The real reason we go is for the amazing sunsets.

Steering Detail

More info on Bonneville, Bub Speed trials , dates, rules, and the current records for various classes can be found here: www.speedtrialsbybub.com

The KOLB 125cc LSR 2013 Edition.

Although I’ve had a dream to race at Bonneville ever since reading about the Blue Flame Rocket Car  when I was  kid in the 70’s it wasn’t until my friend Scott Kolb built a 125cc partial streamliner and started racing it there that I realized now was the time and that I had to get my own wheels on the salt. I first start working on Scott's team in 2009 with my first trip to Bonneville in 2010. In 2010 we set the record for our class and this year we are returning to not only defend that record, but apply what we have learned in the wind tunnel and with a new, more powerful motor and far improved suspension to try to up out record significantly. Bub speed week starts the 24^th of August this year which is 3 days as I write this. Here are a few pictures of the bike in Scott's shop taken about 3 weeks ago as we scramble to get it finished and on to the truck for the trip to Utah. Looking at these pictures you can see where I got a lot of the inspiration for my bike.

I'm the one with the Sunglasses

 

Final Assembly of the Front Hub

Finally! Back to Your Regularly Scheduled Programming!!

MakerBot 2

So this landed in out shop today. It was brought to us but someone who is essentially designing an number of aftermarket upgrades for these makerbot2s and wants Chris’s help in implementing them. It the process we get to use this makerbot 2 with express condition that we use it a lot. In fact we need to really torture test it so that we can find the areas that need to be improved. Just an initial look at the machine and it’s easy to see areas and parts that are marginally designed at best and really questionable in some cases. In a way I’m surprised the machine “prints” as well as it does considering how armature the overall design is. And that, said it really does print fairly well for a $2000 3D printer. I don’t have a good basis for comparison as even thou I’ve seen a number of these 3D maker level machines I have never had a real chance till now to compare them to the real commercial rapid prototype machine made by companies like Z-Corp and Stratsys. Let’s see what this thing can do…