Ive never seen a pop up that says you have a 0 cylinder engine - must be a bug ( is it the latest download ).
The code wont allow you to have 0 in the number of cylinders field, so it cant have been saved like that.
Pack it up and send to Neels.
Re selecting carb size - when you have a seriously developed engine the areas of the Ex, Trans, Intake/Carb all converge.
This then makes it easier to decide where to go first with mods to get the STA correct.
Here is a 50cc bucket thats pretty hard out - notice that the areas all are close to each other, and the actual SmartCarb will have a 25mm venturi.
If you go too big on the carb size, it will be a bitch to get transition tuning right, and any sign of mid power under the pipe will disappear -with no real advantage up top.
Look at the KZ2 engines where we are getting 48Hp at the sprocket from a 125 with a 30mm carb.
I havnt had time to really look at your idea Smitty, had a wedding to get done and a heap of work to finish - will take a serious poke around soon.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
Yes..............
Depending on the set up you have on the forum just copy the address of where you want to link and past it in, or use the button that looks like the globe with a cassette tape under it.
Posting an image or video direct from the web is pretty much the same, except you use the button 3 and 4 to the right of it, if you hover your curser over the buttons they tell you what each is for.
You may have to press the go advanced button near the submit button bottom right if all the 3 rows of icons are not visible.
I have attached the how to do attachments photo display. plus the last three are how to do a link. the photos are done the same way but the icon that you use is as I mentioned the one that looks like a palm tree on a background.
Making progress towards the magic 28, at least now I know this EFI thing is going to work. Just a lot of careful step by step adjustment of the maps is required. I expect time and patience will see it running very nicely.
Blue is where I was when I thought we were not going to be able to squirt enough fuel to get past 11,500 rpm and I also thought it had a terminal deto problem. Deto turned out to be the piston hitting the head. The Red line is where I am now without any sign of real deto anywhere, even in severe over rev. And if I can get the Blue line back with a bit of adjustment, it should be a good little runner.
If anyone is interested, the specs are:- 250 deg Inlet duration, 128 deg Transfers and 200 Exhaust at 72%.
Making progress towards the magic 28, at least now I know this EFI thing is going to work. Just a lot of careful step by step adjustment of the maps is required. I expect time and patience will see it running very nicely.
Blue is where I was when I thought we were not going to be able to squirt enough fuel to get past 11,500 rpm and I also thought it had a terminal deto problem. Deto turned out to be the piston hitting the head. The Red line is where I am now without any sign of real deto anywhere, even in severe over rev. And if I can get the Blue line back with a bit of adjustment, it should be a good little runner.
If anyone is interested, the specs are:- 250 deg Inlet duration, 128 deg Transfers and 200 Exhaust at 72%.
looking good rob , why has it lost the mid range to gain more topend ?, even though on the track it don't matter
looking good rob , why has it lost the mid range to gain more topend ?
Lifting the barrel 0.5mm (one extra base gasket) to give it some squish clearance. Seen it before with these engines going from ex opening at 81 atdc to 80 makes quite a difference on the dyno. 80 must be on the steep downward side of the resonance curve for the pipe, so I am starting to lose that long flat torque curve. With some fine tuning I hope to get most of the Blue line back.
Lifting the barrel 0.5mm to give it some squish clearance. Seen it before with these engines going from ex opening at 81 atdc to 80 makes quite a difference on the dyno. 80 must be on the steep downward side of the resonance curve for the pipe. With some fine tuning I hope to get most of the Blue line back.
same as my brothers rs125 , thought you may of just machined the head to get the squish , but we put a extra gasket under the rs .made 1.5 more hp but lost the midrange , maybe need to get it back as he did feel it on the track in the uper gears as i recall now , but all good seeing what dose what
wobbly, strange thing to me with that carb size issue.
48 sprocket hp from a 125 single cylinder engine with only a 30mm carb. that leads me to think that all those 125 mx bikes with their 38 mm carbs are totally wrong. with only about i guess 35 sprocket hp the 38mm carbs are way too big, aren`t they? so why did the factorys do that if you dont need a big carb like this and can have even more low and mid power with a smaller carb? the 35 hp mx bikes should be happy with a 28mm carb easilie!?
but on the other hand several other engines are running such big carb sizes. 50ccm engines with 32mm carbs are not a joke for example. Frits can confirm.
maybe there is a difference between rotary disc valve engines and reed valve engines. can one say that a reeder needs a much smaller carb than the rotary?
happy new year to all!
WATCHA GONNA DO WHEN THE ULTIMATE WARRIOR AND HULK HOGAN DESTROY YOU!!!!
ill send it off to neels and have him take a look. it lets me go into every subsection except the exh pipe. on the general engine section ive got it saved as 2cylinder so i dont know what the problem could be. 36mm seems right or atleast a good starting point for 190cc per hole so ill probly try the engmod recomendation.
i think maybe why the mx 125 engines use 38mm carb is because they also have a PV to drop the exh roof ? or maybe theyre not concearned much with midrange power
wob you said earlier 190exh didnt sound right. i think i found the problem. i had the front of A transfer slanted forward like many modern cylinders which was reducing the area of the window which made the 190exh STA seem correct. ive since made A full rectangle and that let me raise the exh up to 194 and widen it to 72% and everything matches up fine again. i think this will be a good place to start from anyways. later i can raise it further if need be. grinding it too high right off the bat is probly not a good idea because then how do i lower it again
Frits,you mention your FOS transfer ducts taper towards the bore.
Is this to increase velocity in the transfer streams to cope with the higher RPMs made possible with all that transfer and exhaust area?
Carbs are weird shit. On my old 50 I had a 24,26,28 mikuni all flat slide. After faffimg about with jets I was hoping to get a kart track and a long track setup.
28 gave me the best range and peak.
24 almost matched the peak but worse range.
26 worse everywhere
How are you getting on with the SCs Wob? Dirt bike guys have very varied results and pissing around with tapers on needles and concern about wear. Handled one a month or so back. They're pretty heavy.
Don't you look at my accountant.
He's the only one I've got.
Not sure, could easily turn it over by hand and using solder, measured about 0.6mm over the pin bosses. I wondered at the time about how much the solder would compress the the piston assembly or cock it to one side which would exaggerate the measurement.
Contact must have been only at high rpm, the det sensor would flashed Red at anywhere from 8K to 11k plus depending on fuel and it flashed big time on over rev. There was a clear but very light impression of the squish band on the piston crown.
So dynamically I guess it now has a little less than 0.5mm clearance during over rev.
So there was witness in one area? Best to measure in 4 corners, or you can even take head off and plastercine the solder front to back to answer your question of rock which on a small bore with tight clearances would be less
Don't you look at my accountant.
He's the only one I've got.
So dynamically I guess it now has a little less than 0.5mm clearance during over rev.
And a bit more than that under power, which I would have thought would have been about .4 too much? Will be screwing with the squish velocity, compression, and efficiency. When I set the last motor up which was around 15:1, even .1mm made a huge difference to the compression. The maths is pretty simple.
So dynamically I guess it now has a little less than 0.5mm clearance during over rev.
And a bit more than that under power, which I would have thought would have been about .4 too much? Will be screwing with the squish velocity, compression, and efficiency.
Yes you are right, but it was the easy thing to do, maybe not the right thing to do if your looking for the ultimate setup but this is a donkey motor being used to see if the Ecotrons EFI kit is a workable possibility for a 2T at 13,000rpm and it looks like it is. The real target is the air cooled RGV125.
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Originally Posted by Flettner
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