KR-1S.co.uk Forum

Hi fellas,

Have you measured crankcase and cylinder clearance volumes from the stock KR-1(S) engine? I would preciate to get that information for my MOTA calculations.
I'm intersted of Zeeltronic ignition (CDI-RZ1,VCDI-04,PPV-KR+handheld programmer). What is the real advantage with that and do you have any objective tests made (dyno curve) comparing the stock ignition? I remenber that someone had said that there is no huge increase in power or driveability for stock bike. What mods you think should be made to get some real profit from the engine?

regards

kr1stian

For MOTA work on 400cc for case volume and 10cc for head volume. Making accurate models of the ports(especialy the exhaust) is almost impossible with MOTA.

As regards to programmable ignitions check the dyno chart I have posted in 'RGV Challenge' thread. Zeeltronics work very well if 'someone' told you that you don't gain drivability thay have their head up their ar*e.
There are many things you can do but making them all work together is the trick.

kr1stian wrote: I'm intersted of Zeeltronic ignition (CDI-RZ1,VCDI-04,PPV-KR+handheld programmer).

Don't you just need the PCDI-10K now (plus the handheld programmer), I think Borut has packed the former 3 single units in one package?

The CDI-RZ1,VCDI-04,PPV-KR are no longer listed for the KR1S....

Charles

Most Borut's stuff is made for DC/DC CDI's so the all in one package could work very well. Would make a conversion with the 34mm RGV VJ 22 carb a dream to tune with the variable duty on the air jet soleniods.
Oh kristian if you wish to measure your volume just drill a hole in the centre of an old piston put the piston at BDC and pour fluid into the hole untill you fill to the bottom of the transfers.

Thanks for your answers.
I need to contact Borut about the ignition.
Thanks TSI for the tip for measuring the crankcase. In a matter of fact I have never split the engine cause it still got only 13000km in the clock from new.

Still few thing about the modeling KR-1 cylinder in MOTA v6.10. I made quite handy tool to measure all port dimensions by casting the soft two compound silicone in to the inlet ports and once again separately to the exhaust port. I did it to one extra cylinder I have, not to one in the bike After curing I ripped of the cast parts and place them in kind of stand or jig where the positive cast parts are in exactly same position as where the ports are. It is so much easier to measure for example the port angles that how they meet in the cylinder. I re-calculated all ports and then I modelled whole cylinder in Rhino 4.0 (that is not best program for that work!). All mods based for use of original gaskets. Model was later made with 3d printer.

kr1stian

Kristian,
I don't mean that it's hard to model the cylinder in real life but more like Mota can't cope with a 3 port exhaust it has to be treated as 1 profiled port.The ignition section is compromised in such that it uses a very simple program.With that said it's better than guess work, I have made plenty of good pipes of MOTA.
I would like to see your cylinder moulds.

I modelled the exhaust port as a T shape.
Results tied up reasonably well with dyno runs if you squinted properly

MJ was the shape of the Mota curve the same as the dyno? With peak at the same rpm etc etc?
Sims give a crank HP figure, T ports don't work quite as well as a triple in real life.

would the zeeltronic allow use of tz 250 carbs, the ones with the solenoid type powerjet?

Hmmm yes and no ask Borut he would give you a definitive answer. The power jet just adds fuel where as the solenoids on RGV/TZR add air that being the difference.

TwoStroke Institute wrote:MJ was the shape of the Mota curve the same as the dyno? With peak at the same rpm etc etc?
Sims give a crank HP figure, T ports don't work quite as well as a triple in real life.

It was curve shape I was after not absolute power.
Shape and point peak occurred at was a good match to the dyno runs.

About to resurect Mota 6 as have welder and steel sheet ready to make epansion. Just need time....

TSI asked some pictures to see: There are pics of silicon cast of the (KR-1) ports. In the last picture also seen acrylic circle to estimate the "Radial Attitute Angle" which is needed in MOTA.

I also shaped the exhaust port(s) as T-shape but I just wonder if the 3 separated areas flows as well as one solid area..? If the ports are integrated maybe then wide top area of the exhaust port should be measured a bit tighter to get even more realistic simulation from MOTA...

http://gipsy.pictures.fi/kuvat/KR-1+cylinder+project/

MOTA uses the centre of the duct for the radials not the edge of the duct. The MOTA ignition model isn't the best but as I said before that's better than guessing. Ports can't be realistical modeled and won't account for various scavenging models.

is it possible to take the software prediction results and re-optimise these settings on a real engine/dyno and feed the re-optimised results back into the software to generate a more predictible software model?

no, reality gets in the way of theory. IF the sim output and your dyno figure varies wildy it is the input data that is at fault. First law of databases $hit in=$hit out