[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 3) (Locked)

Piquer a écrit:

For high precision machining and/or specific geometries it is necessary to tie the piece with specific tools for the piece remain perfectly centered and strongly tied without having to centered on each operation or each piece

If you start with the milling process and on a 5 axis machine you can then do all except the outside diameter, ring groove and the dome. These 3 features can then be done in a lathe with a simple fixture afterwards.

Of course all this setup and programming will be the same if you make 1 or 10 pistons so the cost of just one will be high. I've all the machines needed at work just not the drawing. I guess a 7075 T6 aluminium or similar could be a good starting point.

Piquer a écrit:

I asked VHM to make a batch of 20 pistons (I think that is the minimum) diameter 72mm (Bultaco 250, 72x60 engine) and VHM does seem manufacturing to 54mm piston diameter or less (50cc engine).
For higher diameters their should make all new toolings!
But you can ask about it them  

yes i discovered VHM yesterday. ill contact them soon to see what the minimum order is but im afraid 20 minimum is too much for me. what does your 72mm bultaco piston look like ?

heres my original piston 72mm. i will probly have to use it because right now i dont see a better option within my budget

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heres option 3 (worst option) from the last page. gasgas 72mm. it doesnt look good

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but maybe theres one last hope. today i bought 72mm snomobile piston from ebay for $26. i think the side cutout is very high which can make a large hole in the aux ports but im going to see for sure and ill report back the results. if it cant work then its only $26 in the scrap pile. but if it can work then i have 2* ratio of the rod  

brokedown a écrit:

yes i discovered VHM yesterday. ill contact them soon to see what the minimum order is but im afraid 20 minimum is too much for me. what does your 72mm bultaco piston look like ?

heres my original piston 72mm. i will probly have to use it because right now i dont see a better option within my budget

Piston Mahle or Tarabusi was standard for this bultaco engine, but today does not manufactured.
Now we use wössner pistons... They are a shit
We also tested the Hamor piston, distributed by Italkit, They are very bad!  

These are the dimensions of the wössner piston:
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Piquer a écrit:

brokedown a écrit:

yes i discovered VHM yesterday. ill contact them soon to see what the minimum order is but im afraid 20 minimum is too much for me. what does your 72mm bultaco piston look like ?

heres my original piston 72mm. i will probly have to use it because right now i dont see a better option within my budget

Piston Mahle or Tarabusi was standard for this bultaco engine, but today does not manufactured.
Now we use wössner pistons... They are a shit
We also tested the Hamor piston, distributed by Italkit, They are very bad!

These are the dimensions of the wössner piston:
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A Bul piston is no where near close to what he has.

I refer to the differences in wrist pin bore and mods needed.

IOW, no bueno, senor.


I've asked before for some details about that motor, etc.

If you don't want to say, that's fine.

I don't NEED to know.

If the info was mentioned prior, I missed it.

Only curious and following the topics.


But, before making all kinds of expensive mods, you might want to consider that the engineers who designed the thing know " a lot ".

Can you analyze the TRUE effects of any possible " charge contamination " due to the auxillary ports ?

I say it LOOKS extremely minor, and is of no consequence.

Regarding the long rod, if you would mention what you actually have, somebody might provide more info.

If that motor is one that was ever used in any numbers for dirt tracking, WKR might have done what you're thinking.

And another thing is that I was under the impression that the rotary valve motor was what prompted the original idea for the 24/7 deal.

I might be off on that, but I think a rotary's intake layout would be more conducive to such goal than a reed CYLINDER. Not to mention the transfer port arrangement, I'm guessing a rotary retaining " more piston " on its ( usual ) thrust face would be beneficial.

That's to say, in a relative sort of way, piston symmetry with less chopped skirt, equals more stability & therefore, better ring seal / durability.

ambike a écrit:

A Bul piston is no where near close to what he has.

i only wanted to see what it looked like. without seeing it, how can we be sure it wouldnt be a good choice ?    

Citation :

I've asked before for some details about that motor, etc.

If the info was mentioned prior, I missed it.

ill mention it again. 72x72 mx engine modified for drag racing. reeds in the case.  unbridged central exh with 2 aux ports. A and B transfer ports with C rear port.  PV operated by centrifical timer. 125mm rod, 24mm lower pin, 18mm upper. not sure of the primary compression right now and really im not concearned much about it. i want to experiment with the bigger is better approach. if you like small crankcases then please i do not want to hear about it    

Citation :

But, before making all kinds of expensive mods, you might want to consider that the engineers who designed the thing know " a lot ".

the engineers goal was not max power. however that is my goal. if i took your advice and left the engine unchanged, i would never win one race

Citation :

Can you analyze the TRUE effects of any possible " charge contamination " due to the auxillary ports ?

I say it LOOKS extremely minor, and is of no consequence.

im only concearned with gaining maximum power. and avoid any situation that will cause me a loss in power. around here somewhere i believe it was stated how much is the power loss just from the pin running over the transfers and aux ports simultaniously.  imagine if the shortcircuit is even larger or even worse if theres two sperate escape routes. i have to think the power loss gets larger as well.  did you see a rsa125 with piston plug, i hope you didnt think it was just for good LOOKS    . so why have unnecesarry escape holes....

Citation :

If that motor is one that was ever used in any numbers for dirt tracking, WKR might have done what you're thinking.

i never heard of them. but i would rather get advice from jan and frits and other knowledgable members here as i consider them the foremost 2stroke experts anywhere in the world. other forums have alot of imposters who just talk of bullshit and urban legend  

Citation :

And another thing is that I was under the impression that the rotary valve motor was what prompted the original idea for the 24/7 deal.

yes i believe frits mentioned many years ago his rotary disk quit working and his engine kept running. im sure that is the story your refering to

Citation :

I might be off on that, but I think a rotary's intake layout would be more conducive to such goal than a reed CYLINDER. Not to mention the transfer port arrangement, I'm guessing a rotary retaining " more piston " on its ( usual ) thrust face would be beneficial.

why would you use a rotary disk engine with a 24/7 valve ? it makes no sense, atleast not to me.  this has been explained already but i dont recall what page. case reed would be the best way if im not mistaken


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Mic a écrit:

If you start with the milling process and on a 5 axis machine you can then do all except the outside diameter, ring groove and the dome. These 3 features can then be done in a lathe with a simple fixture afterwards.

Of course all this setup and programming will be the same if you make 1 or 10 pistons so the cost of just one will be high. I've all the machines needed at work just not the drawing. I guess a 7075 T6 aluminium or similar could be a good starting point.

i never tried billet piston. does it work good ?

hey guys mostly i just use standard ignition module with non-adjustable timing curve.  but i want to use different ign but i never use adjustable kind before. i see people talk about ignitech. is this a very good one to use for one cylinder 2t  or is there any better ?
 please advise me soon so i can buy it     

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how do i make the timing a good starting point ? do i have to use a timing light from the original timing module and input it to the laptop for the new module then after that it can be adjustable from laptop ?

my stator is just standard mx type with no 12v power. do i have to use a seperate battery or no ?   thnx

brokedown a écrit:

hey guys mostly i just use standard ignition module with non-adjustable timing curve.  but i want to use different ign but i never use adjustable kind before. i see people talk about ignitech. is this a very good one to use for one cylinder 2t  or is there any better ?
 please advise me soon so i can buy it     

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how do i make the timing a good starting point ? do i have to use a timing light from the original timing module and input it to the laptop for the new module then after that it can be adjustable from laptop ?

my stator is just standard mx type with no 12v power. do i have to use a seperate battery or no ?   thnx

You need a curve.

Some do it with a resistor
Some use ignitech With batery for power
Some use innerrotor ignition with programable coil. Like Pvl

All for the same reason.

Find Luc here.
He can calculate your curve allong what your setup is.
Rod length exhaust transfer timing Etc.

S

Hi Brokedown

I hope that you don't mind me saying so, but it sound like your running round like a headless chicken! You need to put together a programme with testing (preferably well monitored dyno running) at each stage. Otherwise your going to solve every foreseeable problem in theory (whether they exist or not), using snippets of information from whoever you chose to believe (and I don't think many on here will claim a great knowledge of 72 x 72mm singles, especially in your particular application). If you continue like that you'll de very disappointed the first time that you run the engine with poor results, because you won't have a clue why it doesn't work as you expected. Your enthusiasm shines through, as does your lack of experience/knowledge and that is what you need to build at the lowest cost possible and without making expensive irreversible changes and becoming dis-spirited. I'm sure you'd also like to have some fun along the way.

So Having said that here's a bit of info on some ignitions that we use (or have used) on our single cylinder engines:

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They are from the left:

1. PVL fixed analogue (black coil) and fixed digital (red coil) internal rotor systems
2. HPI programmable digital, 2-curve switchable (works from 2001 Honda generator)
3. RTD programmable digital DC-CDI, 4-curve switchable (works from 14.8V LiPo or rectified Honda 2002-2007 generator)
4. Ignitech programmable digital DC-CDI, 2-curve switchable. (works from 14.8V LiPo or rectified Honda 2002-2007 generator).

The best results we get are from the HPI and the boxes are very reliable. The RTD gives very good results as well, but is quite expensive. We never got fantastic results with the Ignitech. The PVL digital also gives very good results, but this is not programmable and is burnt with a curve suitable for our engine at  manufacture.

If you do go with the Ignitech, then the only one to have is the dccdip2_race, and power from a 14.8V LiPo.
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I'm assuming your base is a KTM EXC300? There may be an HPI box to suit your generator. If you post up a picture of the stator (with the flywheel removed) and the generator connectors, I will be able to tell you. if this option is available to you.

With any "new to you" ignition, I would always programme in a 25 degree BTDC baseline from say 2.000 to 6,000 rpm and the drop it to 5 degrees from 6,500 to 11,000rpm and verify it with a strobe (having marked up the rotor accordingly) on an ignition rig or on the engine, so that you can adjust the offset of the curve and delay compensation (if available), so that what you programme in as a curve is what you get at the crankshaft.

You can then programme in a very simple basic curve to get you up and running with plotting points as follows:
2K = 15 deg BTDC
4K = 25 deg
10K = 10 deg
11K and onwards = 5 deg

and begin from there. Of course the ignition requirement varies with every change you make to every single engine parameter. This is why whether on track or dyno you need to monitor and log water temperature, EGT and detonation as a minimum.

A large 72mm bore is always much more susceptible to detonation than for instance a 54mm bore, due to flame front travel distance.

Best Regards

Ian 

hi ian thnx for a response   .  yes i would like to test with a dyno but the closest one is 2.5hrs drive because i dont live in the big city. maybe with logical thinking and help from the members on this great forum i can make a good running engine. i realize it wont be the best running engine but i have no other choice. i cant stop engine tuning and sit on the couch just because i dont have a dyno. im sure you understand

heres my plan and tell me what you think of it. my first goal was to find a dome piston but in doing so i encountered the shortcircuit issues like i posted earlier. ill keep searching for a domed piston with no large cutouts but so far it isnt looking promising. in 72mm with domes ive found 5 snomobile pistons and a couple dirtbike pistons (18 and 20mm pins),  some of the pistons and perhaps all of them will leave large shortcircuit holes because they werent intended for this style of cylinder port arrangment.  whats your thoughts on this shortcircuit subject. is it only a small issue and nothing to be concearned with ?  because if its only a small issue then i have many choices of 72mm dome pistons, which will allow the use of much longer rods. also remember i can keep the original flattop piston and still use a slightly longer rod  

next is the rod. i have seen alot of 250 and 300 mx bikes and the cylinders are mostly always straight vertical. i have a theory why most all mx engines use short rods. maybe im wrong but i think its because a rod of 2* ratio or higher would meen the cylinder is very tall. with a tall vertical cylinder it seems the handling of the chassis would be very bad for tight turns and jumps. but remember i dont use this bike for mx anymore, so i wont need to deal with turns or jumps. so if i have the engine disassembled anyways for other repairs, do you see one reason i shouldnt install a longer rod ? i cant think of one good reason to keep a short rod. UNLESS maybe the crankcase volume is already very big and a very long rod might make the volume unacceptably large but really i dont think i would see that problem. tell me what you think

also i want to make new exh flange. now its 40mm ID. but for 300cc i 'think' it needs to be larger. what do you think about it ?  and i want to make a pipe from FOS   

for the port configuration i was thinking to upscale the  rsa125  and apply it to my cylinder. but im not sure if i need to use the angle*areas or time*areas or both. what you think ?

yes i like the idea of programable ignition but i never tried it yet but i plan to get one soon. now i have kokusan 2k-1 stator and kokusan 2k-2 flywheel but i cant remeber the name of the coil but ill have a look. ill get some photos soon so you can see what everything looks like

remember there is no dyno in my garage . so we have to make a good engine with mostly logical thinking   

hey brokedown,

my 2 cents regarding the ignition topic. I think the Ignitech is good value for its money and gives a lot of options. I'd prefer a ignition which doesn't need a battery, but the PVL curve needs to be fixed and the programmable HPI has a really bad reputation. So both no real options, anyway for drag racing a battery shouldn't be a problem.

One thing I learned though is without a dyno you are pretty much screwed with a programmable ignition. You can do a curve like Ian proposed but you'll never know if it's really better or maybe worse. When we first tried the Ignitech it took us 6 hours on the dyno to get power and bandwidth in the same ballpark as with my my preprogrammed PVL. It still wasn't much better and to really get used to it you need some testing time on the dyno in my opinion.

Also listen to Ian, don't try to do everything at the same time! I tried it last Winter and in the end nothing was really finished nor made me faster cause it was just a humble mess. This Winter I will focus on one major topic and hope to finish it   

hi keonich and thnx for the help   . i think your exactly right ! i have overlooked simple things. without dyno a programable is probly worthless, other wise i cant know the true results. and yes i better slow down and change only 1 thing at a time  

brokedown a écrit:

Mic a écrit:

I guess a 7075 T6 aluminium or similar could be a good starting point.

i never tried billet piston. does it work good ?

My understanding is that 7075 has very poor strength at high temperature, and that special alloys are needed for a 2-stroke piston.

koenich a écrit:

HPI has a really bad reputation. 

Reputation is a very funny thing. Sometimes bad experiences with 1 type of ignition or component from a manufacturer, can cloud the whole range

We have been using and selling HPI CDI boxes for about 5 years now. That's a CDI box powered from the motocross generator (Nippondenso in the case of Honda and Kokusan in the case of KTM, TM and GasGas), I guess somewhere in the region of 100 units or so. In that time neither we nor any of our customers have ever suffered a single box failure.

It annoys me that their timing indexing is off (and I've told them!!), but at least it's consistently off, so we just compensate in the programme.

I must admit that we don't like the HPI coil (we always use the genuine Honda or Kokusan coil, but any decent CDI coil will do).

We did always shy away from their internal rotor ignitions in favour of PVL, but have also been getting good results with their programmable system on125cc kart engines (TM, etc) as well.

Brokedown
In our 250cc 66.4mm bore x 72mm stroke we don't see any noticeable difference in either power curve or onset of detonation using flat top vs dome top pistons. I have always "felt" that a dome top should be better, but I can provide no evidence to back up that feeling and at present we are running flat-tops.

The cutout is there for a reason, i.e. to improve flow into the transfers. If you lower the cutout you may make an improvement due to closing the shortcut, but reduce the efficiency and/or mixture distribution through the transfers. The only way to tell that is to do a back to back with 2 pistons which are exactly the same apart from the cutout detail.

27 years ago!! Honda went from a longer rod/lower piston to a shorter rod/taller height piston. Nothing changed in terms of engine height, crankcase volume, etc. So you would have to concede that Honda knew what they were doing (particularly as all the other manufacturers followed suit and now all use 66.4 x 72 with a 125mm rod and a 29mm timing edge height from the top of the pin). I have tried both setups and again nothing conclusive was found either in terms of outright power or spread of power. My personal opinion is that the longer rod and low height piston is better, but that is just from a piston stability point of view.

Of course the exhaust flange effective diameter is again tied in with everything else. But as an indicator our Honda CR250's use a 48mm manifold diameter.

Very generally and in isolation, an increase in crankcase volume on a reed-valved 250cc single will see a reduction in bottom-end power, perhaps (or perhaps not) a slightly improved peak power at higher rpm's and usually a better over-rev. Of course on a 2-stroke nothing can really be taken in isolation.

I never found a pipe calculation programme or an engine simulation package that is anywhere near close for a 250cc single cylinder 2-stroke race engine. We have arrived at our pipe designs by modification and testing.

I wouldn't get hung up replicating the Aprilia cylinder porting on your KTM cylinder, but it might end up looking not far off!  If I was taking a stab, I'd "teardrop" the exhaust sub ports and enlarge the throats as much as possible whilst keeping the cross sectional area as constant as possible. Bring the bottom of the A transfers forward slightly and set the port timing at: exhaust main and subs 196 deg and transfers A,B and C at 132 deg. You can increase the main exhaust port width to the maximum permissible, but I would keep a nice radius at the top corners to help with ring life and remember the thinner the bridge between the sub and main exhaust port, the more fragile it becomes. Remember that you can space the cylinder (thicker gaskets and spacer plates) to check it out before cutting metal, but you would need a few head inserts with identical chambers but different steps down the cylinder. On the CR250 we use a combination of spacing and cutting as you have to be aware of casting thickness on a production cylinder. We use a 2mm plate with a gasket either side (spaces up by 2.5mm on stock). We then cut the bottom of the transfer down by 2.5mm (so still level with the top of the piston at BDC and then we do a little more cutting at the tops and sides of the transfers as required. I certainly wouldn't like to develop a cylinder without the use of a dyno, so best of luck.

Just a final thought. If your piston currently sits above the bottom of the transfers at BDC, you can perhaps space up the cylinder up until it's level, and this might just close the shortcut without changing anything (except the head insert) and set yourself well on the way to a better port timing. Now that would be a good start!!  

Best Regards

Ian 

Ian Harrison a écrit:

Reputation is a very funny thing. Sometimes bad experiences with 1 type of ignition or component from a manufacturer, can cloud the whole range

We did always shy away from their internal rotor ignitions in favour of PVL, but have also been getting good results with their programmable system on125cc kart engines (TM, etc) as well.

you are totally right Ian! I was only talking about the programmable internal rotor ignition from HPI - no experience with their other stuff on my side. They did weird stuff to several people I know, ran half an hour like a champ and then just wouldn't fire up, change settings randomly and finally quit working forever.

Great idea with spacing the cylinder and just design a head insert which goes in the cylinder. Thats a rather easy mod and will change a lot...

very good info ian thnx   .    

i always 'thought' the shorter rod and more specifically a shorter cylinder height had something to do with chassis handling but i could very well be wrong. maybe there is something special about 66.4x72 with 125mm rod because all manufacturers use it but i cant clearly say exactly the reason

thnx for the advice of the dome piston. whether i want to use flattop or not, it looks like it may be the best logical option given the circumstances. but it sounds like ill be just fine with flattop

48mm flange sounds really good. i didnt have a exact number in mind just yet but i was thinking i should have something between 45-50mm.

i cant comment on specific case volume because i havent measured it yet. but like you say, i may or may not see any positive results with a larger volume. losing power at 3k rpm doesnt concearn me much, gaining power at high revs is really my goal

i do have a pipe maker about 2hrs away. he has made special pipes for me before for some of my other bikes but they were of his own pipe design. i would like to have him make another pipe with my design. i realize it would probly be along ways from "good" but if i have the initial pipe built then maybe i can make small dimensional changes in my garage.

now you mention it i think the piston is above tranfer floors at BDC. i recall seeing that phenomenon a while back when i put on the cylinder. ill look more closely how best to aproach that situation but having the piston level with transfer floor makes pefect sense

just yesterday i was looking at a cr500 cylinder and thinking the same thing about raising the cylinder and lowering the transfer floors. thats another project in the garage but i better forget about it for now to keep my mind clear

you guys are lucky to have a dyno within arms reach. if i was that fortunate then certainly i could advance 2 steps forward and only one step back instead of one step forward and 2 steps back but ill keep trying the best i can  

Koenich, Yes I understand and of course in that situation, it is how the company responds and rectifies the situation that really matters. I did have an HPI internal rotor delivered that had no magnetism and also a rotor that had not been tapped to take the puller bolts, but they were replaced immediately.

brokedown a écrit:

you guys are lucky to have a dyno within arms reach. if i was that fortunate then certainly i could advance 2 steps forward and only one step back instead of one step forward and 2 steps back but ill keep trying the best i can  

With 2-strokes, you never quite answer the question. You change one thing (lets say compression) and it makes some positive and some negative differences, lets say more peak power but less over-rev. Then of course you want to try something else that will leave the improved peak power and restore the over-rev, so you shorten the exhaust, but that knocks the bottom end power, so you reprogramme the ignition and then you get detonation and so on and so on. Without doubt a dyno asks many more questions than it will ever answer, but I wouldn't be without it!

However, the racetrack is where it matters.

A friend of mine has a saying . . . . Try 10 things to improve a 2-stroke engine. 9 of them will make it worse and the 10th will make no difference. Sometimes that's how it feels, but that's also the interest ;-)

Here's a picture of our ported 2001 Honda CR250 cylinder, which is in many ways similar to your KTM

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Keep us posted!!

Best Regards

Ian 

that looks like great work there ian.  just wondering how much power do you get from the honda ? do you measure at the transmission output shaft ? also did you make the PV stationary at full open or do you still have it functional in its normal range of motion ?

ive did porting on a couple other engines but they were 500cc nonPV so this will be my first time with a smaller  engine.

On the topic of ignitions, does anyone know of a 90 degree firing programmable 2-stroke ignition? 90/270 firing... I need one for a 90 degree single crank pin engine I am working on.

Riley Will a écrit:

On the topic of ignitions, does anyone know of a 90 degree firing programmable 2-stroke ignition? 90/270 firing... I need one for a 90 degree single crank pin engine I am working on.

Hi Riley

Is it possible for you to use a 2-channel ignition and have 2 pickups one for each cylinder at the relevant positions triggered by a single lobe. If so then you've got lots of choice from the likes of RTD, Zeeltronic, Ignitech, HPI, etc, etc.

Best Regards

Ian  

brokedown a écrit:

that looks like great work there ian.  just wondering how much power do you get from the honda ? do you measure at the transmission output shaft ? also did you make the PV stationary at full open or do you still have it functional in its normal range of motion?

ive did porting on a couple other engines but they were 500cc nonPV so this will be my first time with a smaller  engine.

We replace the Honda stock powervalve assembly, using a CNC machined blanking kit that in effect runs fully open.

We have a Dynapro rolling road dyno that will take karts/bikes and ATV's. We can display true rear wheel horsepower or dynojet horsepower (DJHP) (DJHP has become the "industry standard" of crankshaft horespower estimated from torque measured at the driving wheel(s)). Of course it's bullshit, because it assumes that transmission losses are the same for all vehicles, which they aren't! But as long as you always use the same dyno then it's a comparison tool which is what you want.

We currently getting around 66-67 Hp from our Honda CR250 Superkart Engines

Best Regards

Ian  

Mic a écrit:

brokedown a écrit:

does anyone have experience having 1 or 2 piston specially made ?  other wise i better stay with option 2 from the previous post

You could try VHM in The Netherlands [Vous devez être inscrit et connecté pour voir ce lien] they make 2 stroke pistons from billet.

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I have had Woessner make me 4 pistons for my '57 Piatti, $250 USD each milled from Billet (2618 I presume), incl pins, rings, clips. They require an actual sample but I gave them a perfect solidworks CAD file as well to help them out. Took a year to get it done but I have a feeling that was due to WossnerUSA being inept/braindead. Try going direct.
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GrahamB a écrit:

brokedown a écrit:

Mic a écrit:

I guess a 7075 T6 aluminium or similar could be a good starting point.

i never tried billet piston. does it work good ?

My understanding is that 7075 has very poor strength at high temperature, and that special alloys are needed for a 2-stroke piston.

7075 would be a bad move, I wouldn't even bother trying. Alloy 2618 is the stuff the aero industry uses, and there is another 4XXX series I can't recall now. Really, you only want to be doing this to get you out of the shit, or as a proof-of-concept / rapid prototyping, not as a race worthy solution. Better to source or comission a cast piston, and even better to have it HIP'd afterward. Most forged pistons I see show signs of being dimensionally unstable (especially on warm-up) with scuffing evenly spaced around the circumference, but people will hit both types with a hammer and then tell you you'd be stupid not to use a forged piston   
Maybe if you machined the forgings hot (hot lubricant or steam - as hot as you dare) they may perform better in real life, would be interesting......

best material for CNC made pistons is HITEMAL...it´s new material made from pure aluminium nanopowders...still it´s quite expensive material but it has thermal stability up to 400°C for very long time...we have tested pistons from this material with very good resuslts (wight loss up to 30% ! with same strenght, but about 300€ for one 50ccm piston incl material and CNC works )
this material was developed for F1 pistons in early 2000...

What about RSP ........... [Vous devez être inscrit et connecté pour voir ce lien]