going case inducted!!!

[Theon]

I plan to add a 'block' of alloy to each case half, which will take the stud.
The new intake port would then be machined between these two blocks, to give a similar opening to the original intake port, still allowing the cases to be split.

 

[bensn8]

I thought of the same thing, only draw back for me is that I don't have access to a machine shop here on Guam capable enough to do the machine work. I was thinking about keeping the two mating surfaces flat and just drill holes for a dowel pin, add a gasket and rely on the case bolts to keep the two surfaces together.

 

[Theon]

My father has mill and lathe, but is 2000 KM's away, so I've been saving up a heap of little jobs for when I next go to see him, hopefully in about 2 weeks!

 

[mech_engineer]

Al you need to do is to block the intake port to reduce volume @ crank case and make a 3rd transfer port the same as the other 2. Also the intake port area needs to be 3.2cm^2 for 9k rpm. You are going to go 180 degree @ intake this reduce the intake area because the area is going to remain constant all the 180degree. In the cylinder port you have mean area is like the half of the total port area because the area is going to change during the duration period is going to increase and then decrease this is why the mean area.

 

[mech_engineer]

The luck is on my side, this weekend the engine run faster than ever, reduced vibrations.... Then the engines loose half the power and need to be at high rpm to stay on. Today i opened the engine and a piece of steel make two " boost port" style grooves in each transfer port to the top of the cylinder. I check the piston rings and they are ok, check the wrist pin bearing and it is ok. The steel piece must came from below. I need the special tool for open the engine to give a look. Now i need to rebuilt the whole engine....

Parts list:

Crank bearing.... ordered
.....SFK 6202 C3 open style not sealed can rev higher use the same engine lubricant. The sealed are self lubricated do not recomended for high revs or high temperatures

Minarelli piston 47mm 10mm pin....@ home same as our piston but better quality

JMP high performance copper gasket set... ordered

Light-wieght titanium 10mm Wrist pin... ordered

High Performance Bronze Bushing...ordered

Dellorto 21mm black series carb $33 made in china : ).... @ home

Dellorto velocity stack also a 38mm filter adapter... ordered

UNI 2 stage foam filter... ordered

Crank seals.... ordered

New cylinder ordered

Cylinder and head studs.... i buyed a bolt rod of ss and make them. Like arp for theese engine best material ever... i recomend change every bolt,stud, nuts.. with ss. They are super hard because the carbon inside forms carbides with the cromium and other metal but the cromium carbide is the king there... i tested them and works great..

Banshee reed valves @home

Need a new head( puch hi comp, racing one that they sell here $55, others?) Need help here i accept donations...

Going to powder coated the whole engine case in plastisol is a powder coating like plasti dip texture. To reduce noice.

Need to buy teflon to make the plates for crank case stuffing. Lowest coefficient of friction known will not harm the engine in case of failure.

Any recomendations?

 

[bensn8]

M.E.
Does the width of the new transfer port make a difference? I understand that I should cut the length of the transfer port equal to the height of existing transfer ports but how wide should this new port be? Also, how did you mount your reed valve to the case? Any pictures? Thanks.

 

[mech_engineer]

The same area as the other 2... if you have seen other cylinder have a lots of transfer ports and ours only have 2.

 

[mech_engineer]

For 9 rpm .8mc^2 to .9cm^2 mean area each transfer port

 

[mech_engineer]

Need to be at the same height and same area these mean area are for 140 transfer duration.

 

[mech_engineer]

Available space for make the tranfer port

Other option is to make the same tranfer port and put a flow restriction plate with the area needed for case induction at the cylinder intake port this way we can make the case induction from the cylinder port but the flow restriction plate is critical to do this mod. Because we need to make surethe engine stays in the cycle parameters (i think no one is runing like this an engine. Also need reed valves)

My girl

 

[massdrive]

The math is a road map on paper. I guarantee the reality will have detours and dead ends. How do I know this? Because it's a motorized bicycle and nothing ever works as planned... Am I right or what?

 

[mech_engineer]

Well i do the maths using the the tuners handbook the give the parameters to make an engine run. The proof is arrow case inducted engine 9.5hp. I hope you can read the book if you think i am wrong just show me what i do wrong. Because there is something called specific time area given by the SAE papers made by yamaha's, naitoh and nomura. This number have, opening time, duration, rpm, and area. If you use the parameters the engine will work depending on you desired power band you choose the specific degree*mean area/vol(here again i got degree and mean area and volume). If i am wrong those people are wrong. The first thing you should know every machine you have and you see got math in it. If math is only a low quality road map and humans fly on air planes and go to space i will use these map and not a high tech gps. Just my 2 cents

 

[mech_engineer]

There is a thing called reverse engineering i do this with the cycle parameters having the duration and volume i get the mean area needed. Yamaha give everything we need to know to make the engine run. Also you could build an engine your self if have the tools and machine needed with the sae paper parameters. I will try, if it dont work i will try again.

 

[Theon]

Not quite sure where your coming from Massdrive?
Biggest concern that I see is that you produce to much power for the cheap/crap crankshaft and wrist pin bearing to handle over time. Otherwise you got little chance of getting 9+ HP out of one of these with out doing the math.

 

[mech_engineer]

any one using the pirates cycle hi comp head?

 

[bensn8]

I'm using a puch 70cc hi hi head. It adds a lot to my bike in the mid power range, has larger cooling fins and is cheaper to boot. I can't say anything about how it compares to the head that your asking about as this was the only head that I've used since I got addicted to modding these motors. Still new to this hobby, but for the price ($32.00 +-) it's worth looking at. Hope this may be of some help. By the way, thanks for all the hard work on the math equations and posting it. I in no means am an expert on this stuff nor am I a mechanical engineer and all those math equations really got me lost in the sauce. (Police officer and Army solider is my profession.) but with helpful people like you posting I am able to learn something new. Tell me how to do it and I can. Teach me how to do it so I understand. We all have something to give to this world. Thanks for giving.

 

[slayer60973]

The one thing that hasn't been covered yet is the intake port. How will that be plugged? Bolt a plate with a gasket to it? Stuff it with something? Im really interested in this idea. I'm sure the math is beyond me. Though I haven't really looked at it. I'm more of a look at it, take it apart, study it, and put it back together to see how it works kinda guy.

 

[mech_engineer]

You need the duration for all ports and the mean area, mean are is the area @50% of the duration from port opening to BDC (transfer ports and exhaust port) for the intake is from port opening to TDC

 

[mech_engineer]

Right now i am in design phase we are trying to use the bolts of the intake port to grab the new intake this will eliminate the welding or the drilling and tap. At the same time blocking the intake port. The port must be filled with jb weld to not loose compression at the crank case.

 

[mew905]

2 reed cages from a banshee at $20 ebay some aluminum and welding..., have a dellorto 21mm on my way, all components for the mod cdi and the coil @ home and the engine got the duration and port area from the math. I have almost doble the power by change ports and duration only.

Btw: no where in the internet is port and duration explained like this because all equations are for design new engines, the way i use them is for tuning a engine not for desing one thats why no one understand the port timing from the books

Do you have a link? I've been looking at doing case induction but the arrow reeds were all I could find. Something less restrictive would be perfect

Right now i am in design phase we are trying to use the bolts of the intake port to grab the new intake this will eliminate the welding or the drilling and tap. At the same time blocking the intake port. The port must be filled with jb weld to not loose compression at the crank case.

Are you sure the JB wont get blown out? what about JB with a steel plate bolted in where the intake was to block it more effectively? Last time I put JB in my transfers it melted and blew out but I dont think the intake will reach the same temps.