RC Cars Cox 0.49 (Cox Stocker Kyosho f1,beetle) Killer Bee Backplate New Video!

Hey Guys i just like to give a update. I am still working on the KB Backplate, due to other projects (Becomming a rc pilot, now with a cox powered plane) I had not much time. I tried to start several times without sucess. But the engine turns and sounds like it would like to start

Maybe I have bad fuel or the reed is gummed or something like that. I will take the engine apart again. A spare engine with original backplate is ready to race (The season has already began and I like to hear the screaming sound again , I am sick of electric models (Traxxas Slash Brushless, much power but no sound)

In a few weeks I will assemble the 2nd formula 1 rc car (this time ferarri, showed some pages ago), i have now everything I need including a fuel tank which was really hard to get.

In the meantime my spare parts lot for the Kyosho 0.49 formula cars is growing, so I have enough to do for the next years.

I was bid out on ebay on this :

http://www.ebay.de/itm/261208957158?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

These are the electric versions of the formula car. They are using nearly the same chassis, only some parts are different.

Equal, I have enough cars, but the price was not bad for 4 chassis (I would have slaughtered them for spare parts).

I hope you get the KB backplate to work.

I have been watching ebay US for a kyosho F1 cox, but have not found any.

Over 7050 thread views. This must be one of the longest threads at CEF!

Check for tiny hairline cracks on the backplate, especially inside around the screw bosses. If it burns off a prime nice and fast but then quits, look for a blockage in the needle and spraybar orifices. Make sure the sharp tip of the needle isn't broken off. and possibly lodged in there.

Thank you for the tips rusty-

I will change the needle- BTW: is the KB needle the same as in other product engines?

The spare engine runs great

Tomorrow i will give the kb engine a closer look. Maybe i will run it in the ferarri chasis. I think the red backplate will look great in that ferarri (unless the body is pai nted grey at the moment )

I'm pretty sure the KB needle has the same threads, but the tip taper is more blunt than the tanked Bees. It might work as-is. Or that blunt tip might make it more sensitive. I do know it works in a Medallion spraybar which originally had a sharper tipped needle. There are some rare product engines that have a fine thread, 128tpi needle.

Thanks rusty. Yesterday afternoon I spend some hours in the shop and made the car ready again.

It is now the ,,spare engine'' which has runned yesterday with some additional parts. So I can suspend that the cylinder/head and throttle is ok.

It is assembled with the KB Backplate again, but with another needle.

It is a shorter needle (brass) which is also used in the cox gtp cars. I think the ,,old'' one was a little bit weared out. It looks like a sure start needle (blunt and sharp tipped needle). When you look from the outside it seems that the needle can close the spraybar completely.

Furthermore I have stolen a stocking out of my girlfriends locker, in order to have something like a screen on the engine.

I will try to run it today. I hope it works, if not I will leave the idea of the KB Backplate

It runs!

I cannot say whether it is better than before, but it runs. I have to make some adjustments, the idle is good. If I lean it to the highest possible revs it stalls when I pull back the gas.

I need to find a compromise between smooth running and highest possible speed.

Sadly I had no camera on the hand but i make a short video with my cellphone, where you can see the KB Backplate running:

Today I runned 5 tanks

The car really perfoms good with the KB Backplate. It is great fun to drive. Starting procedure is easy and idling too. Due to the castor based fuel the car is now completely dirty and I have to clean it carefully before the next rounds. At the end the clutch was too hot or sprayed with castor oil and slipped trough. But hey, thats racing. I have other RC Cars but nothing makes more fun than this little whasp. The sound is really great, due to the KB Backplate it is a little bit louder and more hungry than before.

Here is another short video from the little bastard I made with my cell phone while idling, sorry for the bad quality. I will add a driving video soon. Really great fun :

After fooling around with the reed valve engines, I thought I'll get the tee dee project out again.

I have drybuild the engine the ferrari chassis to see if it fits. I think it looks quite ok. Now I have to build a motor carrier probably from aluminum.

Is it possible to turn the venturi at the tea dee's actually? In this position I'm certainly not able to get an acess to the needle. The whole thing will be housed in another chassis and I would like to add a camaro body or something like that. The cooling will be guaranteed by a small computer fan.

I'm curious what you think of my idea and would like to invite you to a inspiring discussion. Pictures:

Actually i am thinking about how to fix the engine on the original backplate. I have to reach the correct position of the spur gear.

Btw: i have another video of my f1 car.

By turning the venturi, do you mean to make on its side so the needle points up? Unfortunately, no. It has to be in that position. All you can do is flip the NVA over so the needle is in another position, but still horizontal. 4 different positions, but all horizontal. That looks good if you can figure out how to access the NV.

How about a remote NV?

Thats an option rusty ! But it will stress the budget and another difficulty is, how to reach the servo arm. But i will keep it in mind. Maybe i can reach the needle from underside of the car, there is a hole for cooling under the engine.

For the needle valve... What about a stiff length of tubing, pushed onto the needle, long enough to curve away from inside? How about a short, stiff, but flexible cable, clamped to the NV, similar to a needle buried in a cowl on a model airplane-an extension like O.S. provides?

Good idea, i will try this ! I have to modify the chassis in some details, it is very narrow around the nv.

The servo arm of the valve throttle is also very close to the venturi but i will find a solution.


Thank you for tour help guys

Yesterday i made a short running video of the f1 car with kb backplate. It had rained before and the street was a little bit wet, but no problem for the car and engine:

Moves along pretty good. Nice!

cribbs74 wrote:Moves along pretty good. Nice!

Thank you. I have to make a better video with a real cameramen but did not find anyone who has time for my little hobby . The car is a little bit weak on low torques (but for 0.49 cui it is really not bad I think). It needs a long run up distance to fuel speed.

For me the car is now in good shape, I will make some adjustments on the front steering and have to fix the body on some parts.

Now it is time to rebuild the ferrari (same chassis with different body). I have to remove the old paint in order to spray it in ferrari red. Due to the modest availabillity of this cars and the mint new in box condition of the car, it will be a shelf queen with limited missions (only on perfect weather conditions and a long lasting cleaning session = castor pollution is a paroxysm ).

The 0.49 Beetle project is still to be completed. The starting mechanism with the well known spring starter is a faulty design (just in this case not on the planes!!!). I did not get it to run yet. The engine was nib, has a new backplate correct fuel and so on. Maybe the spring starter is worn out.

Too many projects (I am still working on the cox rc airplane too) at the moment.

I think I will spent all my time on the tee dee powered car, the biggest problem is a engine mount at the moment. If anybody has an idea which basic material I should use (the chassis is made of delrin) please advice. I am thinking of aluminium, but I would like to have something which is durable too but easier to handle (I have only a limited machine park, otherwise a cnc finished engine mount would be my favourite )

At this stage I like to thank you all for your sympathy on this topic. My old Cox car bring me back to modelling, it is still a great hobby.

News:

Yesterday I cleaned and rebuild the drivetrain of my spare car for the tee - dee project.

It is now a high performance drivetrain. I have changed all bush bearings to ball bearings. It is rotating much easier now.

I am curious how this will work on the track, but I think it will enhance the performance a little bit.

Complex little machines, I'm still amazed. I wish I had known back in the good ol days.