APS/Ω Gas turbine bike build

[salt27]

Now that's a bunch of crazy Swedes!  You sure know how to have fun. I think you should retire the trailer though, it looks like it's made it's last trip.

I would not underestimate these Swedes mechanical ability.
Replace the wood and add a couple overlapping patch panels, good as new.   

[Mobacken Racing]

He he, I think the caravan has made its last trip. I was a bit worried that the whole top would fall off on the highway, even though we had tied it together with ratchet tie downs over the roof...

[Mobacken Racing]

With the jet kick racing done for the year it is about time to get the bike sorted out for the summer racing, so far I have made good progress but I really want to get it ready for a test run as soon as possible so I know that everything is ok.



I made the last brackets for the side fairings and asked my feancee to take a couple of photos with me on the bike so I could see how the fairings follow the leg angle.



The rules for the APS bike class says that the legs must be fully visible from the sides, plus I don´t want my legs to get caught on the fairings when lifting them from the ground to the foot pegs when starting a run.



I could see that there was a bit of trimming to do, aluminum is as you can see much easier to work with than stainless.



Now it looks much better, no problems moving my feet off and onto the footpegs any more.



When I sat on the bike I noticed that my right knee hits the connections for the air and propane hoses, so I decided to move them and at the same time mount them much sturdier than before.

On a side note I can really recommend Migatronic tig welders, they are a real pleasure to weld with compared to the machines I have used before.



The fittings are in place, now they are both out of the way and fitted rock solid.



Cheers!
/Anders

[tauruck]

You work so hard!!!!.
Anders, it's a pleasure to follow your build.
Thanks man.

[Mobacken Racing]

Thanks!

I also found time to finish one more thing on the "to do" list for my new JU-02 engine, and that was securing the compressor cover radially.



With the help of a bit of duct tape I had the compressor wheel centered in the cover and could drill two 4mm holes through both cover and diffusor plate. They were then threaded for a pair of M5 screws that would act as dowels.



And the job is done! I used screws with an unthreaded length close to the top where it fits through the compressor cover, this gave a very snug fit which will center the compressor wheel in the cover every time I assemble the engine.



Cheers!
/Anders

[tauruck]

Great innovation.

[Mobacken Racing]

Great innovation.

I would have prefered that the cover screws would do the aligning but since the radial clearance for the compressor blades is only tenths of a millimeter it is just not accurate enough.

Hopefully I won´t be disassembling the engine between every single run so I don´t mind having to remove these "threaded dowels", I have built the engine with ease of overhaul in mind so I think I will be able to remove the engine from the bike, disassemble it completely, put it back together and have it back in the bike within an hour.

Do that trick with an inline-4 bike...

[Mobacken Racing]

The only real issue I´ve been having with the bike during the runs is that the engine tends to flame out when I start braking, the oil is thrown forward, the oil pump pickup sucks air and the oil pressure switch cuts the fuel pump. With a full oil tank and easy braking it can be avoided but it is definitively something I need to fix.



Point of no return...



Now both tanks have a nice big hole in them, the fuel tank has one internal baffle but the oil tank was completely empty. I must have forgotten to add baffles to it before I welded the lid on, no wonder I have had problems with it...



I made a pair of stainless lids and borrowed a nut riveting tool (don´t know the english word for it...) from my friend Olov.



I really need to get me one of those, a very useful tool!



I removed the fuel tank baffle and spent the next half hour cleaning out the fuel tank, when I was satisfied I cut out a block of tank foam for it.



I will fill the oil tank with foam as well, a bit unusual perhaps but I cannot see why it wouldn´t work with 0W30 oil just as well as with kerosene. I guess I will soon find out, with the newly added lid on top of the tank I can easily remove it if it for some reason won´t work.



Cheers!
/Anders

[Stainless1]

My experience with that foam is "you better have a filter"
 

[Seldom Seen Slim]

http://i231.photobucket.com/albums/ee196/Anders811017/Anders%20projekt/Johansson%20Unit%2001/JU-01%202259.jpg

I'd like to have the braided hose concession at your parts shop, Anders.

[Mobacken Racing]

My experience with that foam is "you better have a filter"
 

Is the foam constantly releasing particles or is it just when it is new?

[saltwheels262]

It looks like the threaded inserts you are using are plusnuts. On those the shanks have splits in them. The other solid threaded inserts are called rivnuts. Same tool for both inserts. They come in aluminum and steel. They can be had to clamp different thickness materials. I have used them in plastic material also.

Franey

[manta22]

Franey;

They look like generic versions of Rivnuts to me. Originally developed in the late '30s or early '40s to fasten de-icer boots to wing leading edges if I remember correctly. Very useful little devices!

Regards, Neil  Tucson, AZ

[saltwheels262]

Could be. You are probably right.

[Mobacken Racing]

I did a scientific test with the foam today, first I boiled it in water for half an hour while making dinner. No problem at all.



Then I dropped pieces of foam in both Jet-A1 and 0w30 oil, they were just fine after an hour but I will leave them in for a couple of weeks and check in on them again.



I ran the oil tank in the hot water cleaner at work until it was perfectly clean, and tonight I cut a block of foam and fitted inside the tank. I left a small hole closest to the oil returns so the oil can get into the tank without anything blocking it.



There is also an empty space at the bottom where the oil pickup is, the theory is that the large foam area will flow more than enough oil down to the pickup even when the oil is cold. As soon as I have run the oil through an external filter to clear out any piece of dirt in the foam I will run the oil system for some time to find out if it will work.



I cut out a gasket for the lids and fitted them with a layer of gasket silicone to make them seal correctly around the riveted nut heads.



My original idea was to have the tanks painted black just like the fairings, but I decided against it since I might have to modify the tanks in the future and having them painted would complicate the job.

Cheers!
/Anders