Two Wheeled Stinker

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Two Wheeled Stinker

I’m a bit confused by compressed air starting ? That’s no good in the air if you, for what ever reason need to attempt to restart an engine and you’ve not got enough air charged up to do it??

These days general aviation is going much the same way as cars with smaller more economic and cleaner engines.

When you can buy a whole car for £20k it doesn’t make sense that your aircraft engine that was designed in the 60s with a displacement of 6+ litres and only 160hp should be costing £50k that said aircraft engines no matter what are not cheap but they don’t need to be that big or heavy and they can be smaller, lighter and more powerful which is what Rotax are doing with their engines.

I don’t know much about the cross 4 but I suspect firstly as an air cooled Diesel engine it would have had to be an iron construction. So very heavy, then it would have been two Stoke so notoriously dirty emissions wise. And again a fully mechanical engine tends to be more simple/dumb which means no clever management of the engine resulting in sub optimal running configurations, and remember a car ending might go from 0-3000feet altitude but a plane engine needs to be able to manage the fuel air mix maybe up to 17,000-20,000 feet if carrying O2

The concept is genius but I’m assuming there were a lot of problems they’ve not been able to overcome.

The hawk engines you mentioned seem to have hit a similar wall having not made it into any sort of series production and only found there way into a few prototypes.

The only real advantage to a turbine is massive reliability as there are so few moving parts, also power, they don’t produce massive power on a little plane but for there size you can double your power for half the size and weight. They are much better on noise and of course vibrations but the costs are just insane. Something like a kit built Vans RV 10 might cost £50 for the aircraft but a turbine engine is going to be double that, versus £40k for a conventional new lycoming.

Something like that cross 4 or cross 8 would need some sort of aircraft designed around it, what I love though is the radial engine appearance.
All I know about airplanes is that I'm in them almost every week and they're either an Airbus 32X or a Boing 7X7. Sometimes an Embraer or CRJ, too. And they're usually parked as far as possible from baggage claim. ;)

The CVT showed up 4 days earlier than expected. Big thing.

I guess I better get some argon so I can make sparks while I'm on vacation.
As you say homologation is a huge problem for new designs. Nobody wants dangerous aircraft engines but the clunky 1940s petrol engines still in use are not especially reliable. Seized valves killed a friend of mine. How often to road engines suffer seized valves?

The two stroke diesel is actually very clean. They only get dirty when over injected (as US truckers used to do with Cats and Detroits). The big advantage is the natural air blowdown when inlet ports open. The Zoche dry sump lubrication loses very little oil. Air does not go into the crank case. Saying that, Ford and later Rotax proved that a crankcase breathing stroker is not dirty if it's breathing clean air. Rotax cut the oil feed by 50% when they stopped washing it away with petrol.

During WW2, Rolls Royce worked on the Crecy engine. A sleeve valve direct injected petrol two stroke. Tests by Ricardo on V twin test mules estimated the 27 litre V12 could make 5000 bhp. However, the best engineers were kept on Merlin and Griffon development so "silly" errors like the oil pump being too small were not spotted. Also nobody noticed that sleeve valves were probably not needed.

It was overtaken by turbo jets and turbo props.
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One step forward, two steps back. It was great to get the CVT four days early. Not so great that of three possible bolt circles on the crankcase, the CVT fits zero of them. Not the end of the world. Just one more facepalm and head shake that causes me to walk away for a few days and work on something else.

So, my 1977 Velosolex 4600 now has a new fuel tank and its engine lift is now working like it should. :)
Not really. I’m just going to layout where the holes need to be on the plate and make use of my drill press.
Made the plate fit on the diesel today.

Drilling out holes 1, 2, and 4 were a piece o' cake. Hole number 3, grrrr. There was something in the casting at that spot that broke my 2mm bit(yes, I use metric drills on this side of the pond). I ended up hogging out a lot of material with a carbide dremel bit until I got past the broken bit and what ever broke it. Followed up with a 9mm. Holes 1, 2, and 4 lined up perfectly. Hole 3, eh. That's what rat tail files are for.
This is the alignment I'm looking for between the driver clutch and driven pulley.

It looked like I needed a 32mm spacer for the driver but, alas, I need 36mm. So, I need to scrounge up a 4mm/.125" shim.

Got tired of messing with the engine, so started working some on the frame. Did some slicing and dicing.

Bent the tubes to almost fitting, too. Always fun working with an oxy-acetylene kit while wearing shorts.

Today, I rebuilt the front brake caliper. It was pretty stuck but came apart with 120psi of compressed air. Once those pistons started to move, they were coming out. Now. Cleaned up the crud in the caliper and pistons with my ultrasonic cleaner, then polished the piston and bores with a soft wire wheel on a dremel. Reassembled with all new rubber bits and mounted back on the bike with a new master cylinder. Letting it gravity bleed for a while.
I've been ridden hard and put away wet by my employer the past couple of weeks, so all that has gotten done is that I did get the frame tubes tacked in place. So that's something, I guess.

May is looking really busy, too, with work trips to NYC, Kentucky, Florida, and Puerto Rico by the end of the month. I expect them to cram as much on me as they can before I retire at the end of October.

All that said, my wife and I decided to take advantage of the nice weather the previous weekend and did a cheeseburger run in the DeSoto to a place we like in Hinckley, Illannoy.
After wrapping up the Jeep and the little snowmobile over the holidays, I got back to the stinker. Right now, working on getting the engine into the frame. Not as fun as it sounds. It does almost look like it was born there.

Until you get to the other side. Hmmm, that pulley needs to be on the other side of the frame tube.
On this side of the pond we'd say it was 4th down and 10, time to punt. I need to do some serious rework to the down tubes get the engine and CVT in place.
Now with the engine offset a little, it will go around corners one way much better than the other. Might need to add ballast, or sit sidesaddle.
Just like driving a sidecar. However, once that big ass flywheel gets spinning, it will probably stay upright on its own. It'll still vibrate like hell, though.
Just like driving a sidecar. However, once that big ass flywheel gets spinning, it will probably stay upright on its own. It'll still vibrate like hell, though.
Bikes that cannot lean also cannot steer making any significant gyro effect - erm - "uncomfortable". All bikes (pedal to car size) steer by using cornering forces to make the machine lean and turn (counter steering). You then use the same forces to stand it up again. A momentary push of steering to the left causes the bike to lean right and go right. A momentary steer to the right stands the bike up again. We say push the right bar to go right and the left bar to go left but like the tiller on a boat, the actual steering effect goes the opposite way.
Bikes that cannot lean also cannot steer making any significant gyro effect - erm - "uncomfortable".
Also known as 'flying the chair' when done purposely and 'oh, ****' on accident. Sidecar rig handling has more in common with snowmobiles than bicycles or motorcycles.
New tubes bought and marked for cutting. Not bending this go round. This time I compensated for the starter. I ordered a tube notcher from Amazon that should be here next Tuesday, but I won't be. With the tube notcher, I can build myself my own bike frame when I'm done with this mess.
Have a look at what Norman Hossack did with bike suspension. His original idea was to separate braking and suspension forces at a cost lower than tuning the telescopic forks of the day. Tele forks have improved but hub centre steering has always been a holy grail of bike design.

The Hossack fork is made with notched and welded steel tubes with rose joints for adjustment so the total precision demanded by telescopic forks is not necessary.

He also made a leaning three wheeler, which he kept quiet about, but it really did work. He had two suspension arms jutting forward from the frame (just like his normal forks) but the front wheels sat on a parallelogram linkage that could freely lean left and right. The front beam was two solid tubes going from one wheel to the other with ball joints at the ends and pivot bearings in the middle. It leaned and steered like a normal bike. Hitting a bump put 50% of the force into the suspension and 50% into the other wheel increasing grip on the "un-bumped" side.

I reckon you could come up with a version that give you three wheels and leaning like a bike. Attach a brake to the leaning arms and you'll not even need to put your foot down when parked.
The tube notcher arrived last week and my first thought was "Who the hell inspected this thing?" Threading for hole-saws under 32mm is 1/2"-20. Threading on the shaft was M12x1.5. The internal threads in the adapter for the larger hole-saws were so buggered that it was useless. Also, it was advertised as having an internal bronze bushing where the shaft runs. Bullsh!t. Sounds like this should be in the grumpy thread, doesn't it.

I left a scathing review on Amazon but instead of returning it, I decided to make it like it was advertised. I took the shaft to my friends machine shop and had them face off the M12 thread, then bore and tap for 1/2"-20. Used a 1/2"-20 set screw as an arbor. I could have done that myself, but I don't have a lathe. It would have been a PITA on a drill press.

The bore of block with the supposed bronze bushing that the shaft passes though, measured 19.3mm. The OD of the shaft was 18.75mm. A lot of slop. I bored the block to 22mm and pressed in a 22mm x18mm oil lite bushing in each end. Then ran an adjustable reamer through repeatedly until the shaft passed through smoothly. Measured 18.79mm there.

Slapped it all back together and did a 5 degree test cut on a 1" tube using my 36V Bosch 1/2" wrist breaker. Perfect.

I did that last night and wrapped things up about 6pm. Thought about going out to the garage this morning to cut and tack weld tubes to the Stinker but the temperature outside is -20F. That's a big NOPE.