The 50

[cotswold]

That would be a question I would ask the resident physicist he would I think welcome a non Ryger not really Aprilia question I imagine.
I say yes , not I am not really that clever

Not sure Frits reads this section so I hi jacked Robs page to see if I could direct him here

[Frits Overmars]

Not sure Frits reads this section so I hi jacked Robs page to see if I could direct him here

No, I wasn't aware of this section. Jeez! Another 20 pages to read .

[cotswold]

No, I wasn't aware of this section. Jeez! Another 20 pages to read .

no need to go back that far, it's just the page before this one that has the diagram of yours that needs a little math

[richban]

Rich we had .54 squish
Thanks for the info on head shape as I was going toroidal but a European mate and now you have said bath type, I'll stick a photo of his when I get home
Pleased you are putting a 50 together be great to see a grid full at the GP
YOu should leave the motor stock ����

Ha ha standard. No fun in that.

I like the sound of this most winniest pipe Frits has posted.

We used this shape for the 300 to hit an MVS of 38.



Also this worked really well. No real back to back test so can't confirm the best option.

[Frits Overmars]

no need to go back that far, it's just the page before this one that has the diagram of yours that needs a little math

I like to know what I'm dealing with so I had to read the full 20 pages.

So as mine is pretty much square if one were to use an appropriate bit o maths could one use this as his template?

In case you're not only interesed in the pipe but also in the combustion chamber pictures, here is how to distinguish them.
Look for the filename top left and if that doesn't help look at the value of X1: that's the cylinder bore.
X1=70 was a chamber for a Suzuki 500 cc twin.
FOSCYL01 = 125 cc FOS cylinder
A125HEAD = Aprilia RSA/RSW125

Pipe GARTWIN was the Garelli 125 cc twin: six straight world titles. But this pipe is 30 years old and you would have to convert the dimensions to a 50 cc engine.
Save yourself some work and start with the FOS Exhaust Concept that I posted somewhere on Kiwibiker.

By the way, I won't be looking into this thread on a daily basis; I need my two hours of sleep each night.

[cotswold]

I like to know what I'm dealing with so I had to read the full 20 pages.

In case you're not only interesed in the pipe but also in the combustion chamber pictures,

By the way, I won't be looking into this thread on a daily basis; I need my two hours of sleep each night.

It's ok Frits I am not a serial poster but do like to post when I change something.

It was the combustion chamber shape I am interested in at the moment, my pipe seems to work well enough for now but will be re visited after I have finished tinkering.

Thank you for taking the time to look, it is only due to the help of my friend Jenne Smit and of course TZ that the bike runs as well as it does, saying that there would be no bike if not for big John Steer

[cotswold]

If plan A falls through, I'll ride your bike, only chance I would have of taking it to Malcolm.

Anyone else planing on trying to collect the whole set? I know the hillbillies are building sidecars.

put a dremill to your 100 and cam it

[kel]

So as mine is pretty much square if one were to use an appropriate bit o maths could one use this as his template?

This is the standard offering and exactly what you'll get (unless you supply your own design). You do have to keep in mind this design was optimised for unleaded race fuel not the dirty leaded avgas we use. Sketchy machined up the first batch of these about a year a go. I was hoping to see some back to back test results from the RG50's

[cotswold]

This is the standard offering and exactly what you'll get (unless you supply your own design). You do have to keep in mind this design was optimised for unleaded race fuel not the dirty leaded avgas we use. Sketchy machined up the first batch of these about a year a go. I was hoping to see some back to back test results from the RG50's

I have just been given a set of drawings for a head by an engine tuner out of the uk, I have tried a couple of times to send them to you but not working for some reason, they are specific to my piston but still need tweaking for the deck height.

[kel]

I have just been given a set of drawings for a head by an engine tuner out of the uk.

Got it. I like the ribs for added cooling.
What about fuel, is this insert designed for a motor running Avgas? I've seen it asked on Pit-lane.biz what the optimal chamber shape might be for Avgas but I haven't seen an answer.

[cotswold]

Got it. I like the ribs for added cooling.
What about fuel, is this insert designed for a motor running Avgas? I've seen it asked on Pit-lane.biz what the optimal chamber shape might be for Avgas but I haven't seen an answer.

I'll ask him and get back to you

[cotswold]

Got it. I like the ribs for added cooling.
What about fuel, is this insert designed for a motor running Avgas? I've seen it asked on Pit-lane.biz what the optimal chamber shape might be for Avgas but I haven't seen an answer.

Mark just got back to me and it's 98 for this design so all good

[kel]

Mark just got back to me and it's 98 for this design so all good

You are already running unleaded then. Need to make the switch myself. Im sure with the fast burn, less ignition advance, lower compression, richer mix of unleaded that its got to be good for the air coolers. Elf MITS ...

[FastFred]

You are already running unleaded then. Need to make the switch myself. Im sure with the fast burn, less ignition advance, lower compression, richer mix of unleaded that its got to be good for the air coolers. Elf MITS ...

Lets not pussy around with that cheap toxic carcinogenic unleaded 91-95-98 shit people get from the local petrol station, lets go totally open fuel and brew up something decent with the now legal Elf MITS.

[richban]

So now I have joined this 50cc arms race. Actually its back to where it all started truth be told. First bike ever was an MT50 second bike GT50E. Me Bro had a 50E bucket.

Anyway Back to the question I was going to ask. What is the best HP anyone here in NZ has got from there 50? anyone ever had 18hp? See as I am not very light I figure 18hp would be just the ticket on my new RS50. So that is the goal. I will post the disappointments as I go. Maybe I will start a new thread for the build.

There is not a 4 stroke left in the shed. The transformation is complete. NSR300, CAGIVA raptor 125, RS50 and TF/RS100 project. Oh god what happened to me.