Supercharged 2-stroke engine

[supercharedcustoms]

Here's the deal, Yes the rod and piston are getting treated, also I am testing the rods for compressive and tensile strength before installing. Also I am already running an expansion chamber between the carb and port along with the supercharger. For fuel I am running 100 octane (r+m/2 method) sunoco race fuel with a 12% nitro mix and using amsoil synthetic two-stroke oil, and an ngk plug that has been gaped down. I understand this subject is highly controversial and many have their doubts, I have been running trials on the engine and tweaking as I go along. I am waiting for paint to come in so I can paint the bike, I am also playing around with gearing and rim size to get it where I want.

 

[supercharedcustoms]

While I can see this working in principle I'm not sure this is a great idea with something with such variable build quality - have you seen what happens when a supercharged engine throws a rod?

I saw a tractor-pull once where some bright spark had put 4 supercharged tractor engines inline on one chassis - the black smoke was impressive enough - the white smoke, and flying rod complete with coconut sized flying piston that imbedded itself into the earth by a good foot - was even more impressive (especially to the 5 year old girl it missed by inches)

Having that between my legs at 30+mph is not something I wish to experience.

I can see how this would work - Ettore Bugatti came up with something similar although in his case it was a chain driven double lobe rootes type on a 18cc engine - but I would trust his engineering and quality control much more than I would a CGE

I personally see little point in this since with a little work a frame mount setup could easily be made to take the current crop of 4-5hp 2 stroke tuned engines from people such as DDM - twice the power on half the displacement - not to mention you'd get more power yet with a tuned pipe and my low percent nitro/petroil mix... True they are more expensive, but you get what you pay for and personally even the NA CGE's have always been a false economy.

By all means see if it can be done - but I would be very suspicious if this could be done safely with the current stock of CG engines - and if an engine of this configuration fails under load I for one would not want to be the person liable for supplying it... because if it throws a rod or a piston through the side or head the only bits between it and the outside world in general will be important parts of the riders anatomy... not to mention the resulting accident and the injuries that could cause...

Jemma xx

Heres the deal I am running nitro, I am running a tuned port exhaust or I would not be able to get proper resonance to get this engine to run,Ettore Bugatti builds 4stroke not 2stroke totally different ball game, I am running gasoline and nitro and syn. oil mix not diesel which is injected in at tdc. I have seen a thrown rod blow out of an engine. We were in a GEO metro doing 91mph down a hill and had a rod blow a hole in the hood when it came out the side of the 1000cc 3cylinder engine yeah it is a little scary but that is why i am testing everything before I release all the details of this build. I dont want others getting injured off of my design if they attempt to copy it.

 

[supercharedcustoms]

Supercharging a 2 cycle sounds impressive.
What are you going to accomplish???

All you do is increase the pressure in the case.
If you increase the pressure too much you only blow the fuel outta the exhaust.
Transfer port and exhaust port are open at the same time.
Not much gain there more of a loss.

There is an optimal pressure for the motor.
Supercharging is more harm than good.

Supercharge a 4 stroke not a 2 stroke.

That's the best advice i can give you.

By having the intake port open slightly longer boost can be obtained. compression on these china engines is low... like 6:1. while heat is increased as the compression is increased by ceramic coating the inside of the exhaust heat is taken away from the motor much quicker. supercharging a 4-stroke is easy and everyone is doing it. not everyone is working on the 2-stroke not because it cant be done but simply because it is harder.

 

[arceeguy]

While I don't hate the HT engine like jemma does, a supercharger on a HT engine is about as useful as titz on a turtle IMHO.

 

[Motorbike Wanabe]

While I don't hate the HT engine like jemma does, a supercharger on a HT engine is about as useful as titz on a turtle IMHO.

Hey, maybe the men turtles are into that sort of stuff!

I say, it's your bike, your engine, your nubules. Be careful and creep up on it from the side of caution. Most of all, let us know how it goes.

You're either simply addressing whatever roadblocks are thrown up in front of you on this forum or, you're addressing the issues. When we see a youtube of it running, we'll all know.

Good luck with it.

 

[Lemsteraak]

The Bugatti supercharged 2 stroke engine is very cool. There are pictures and specifications somewhere on the web. I would study his design because it would be a huge engineering challenge, not a simple bolt on.

The difficulties are profound. Not as simple as pressurizing the intake, for example, you have to balance the pressure inside the carburetor. Then you have to balance the pressure for the fuel intake otherwise the higher intake pressure will simply blow the fuel back into the fuel tank.

Personally, I don't see the point, other than a design exercise. Two-stroke engines are pretty much a dead end here in the States. I think you would be wise to look into some of the new engine designs like the Ecomotor
http://www.ecomotors.com/
They, like you are after the holy grail - power density

 

[Lemsteraak]

The above post is incorrect, I said the Bugatti engine was two stroke, it is actually a dual overhead cam four stroke supercharged engine.

Here is a link to the Bugatti Type 72
http://www.bugattirevue.com/revue29/t72.htm

The only supercharged two stroke engine that I know about is a GMC diesel they made during WWII, the venerable '72 series. If I remember right, they had exhaust valves, otherwise the incoming charge would blow right through.

 

[supercharedcustoms]

Latest scoop- so i got the porting down to build pressure and she screams like no other got 3psi of boost at 61 mph with a 32 tooth sprocket on a 30" tire which is nothing like I have every rode before... little scary especially with only coaster brakes. got two healthy 10 min runs on her, all seemed well it was hot but it was not running lean or to the point where parts would fail. On the third run after about 17 mins in the piston basically melted to the wall of the cylinder locking up the rear tire at 25 mph in town scared the s*** outa me at first and then I had to laugh because I realized what really happened... while that was prolly the longest black mark on pavement left by bicycle i had ever seen, but in the end it was all worth it! Heres how I look at it, yeah I blew a bunch of spare time about $70 in parts and materials, but I had fun, learned some things along the way and have an excuse to rebuild my cruiser into a more chopped out bike with a new top end on the engine. Next time I supercharge a bike it will be with something much bigger maybe a snowmobile motor......

 

[Drunkskunk]

Can't wait to see it

It may be as pointless as T1Ts on a turtle, but that would make one s3xy turtle!

 

[Motorbike Wanabe]

Pics! We need PICS!!!!

Even if it is of the carnage. Let's see your setup before you dissect it. Then, let's see the gooey guts. It's like a slasher movie for motor geeks.