ESE's works engine tuner

[ken seeber]

. I was thinking a light twostroke with lots of power and a paddle wheel one for the driven front wheel as well
.

Turns out the F1 was all 4 strokes, so had some time to help Neil with the design. No charge.

[TZ350]

Now that my new bike is nearly ready I need to develop a new Alpha-N fuel injection map. The axis's of an Alpha-N map is throttle position TPS and RPM. The steps between cells need to be in even steps. That is not even RPM or TPS steps but even changes in engine load.

"Torque" is largely related to the motors Trapping Efficiency of the air passing through it.

"Delivery Ratio" is everything when it comes to quantifying airflow through a two stroke motor and it is the air flow that needs fuel added to it in the correct proportions. Trapping Efficiency is the measure of how much of this air/fuel is trapped to be com-busted.

Initially I thought changes in Torque could be used to represent changes in engine load and could be used for developing a fuel injection map. Well that might be Ok for a four stroke but now that I have tried that approach I now think that Delivery Ratio is the more suitable measure for developing a two stroke map.

Air flow (Delivery Ratio) through a throttle is not linear. The greatest changes happen between 20 - 40% throttle opening.



The first requirement is to find the throttle openings that corresponds to even Delivery Ratio (air flow) steps.



Then I modeled these throttle openings in EngMod2T and got a reasonable correlation and reasonably even layer of Transfer Efficiency steps in the power region of the simulation.

This information at each TPS position and RPM point should make a handy start for developing the new map.

The rest of the simulation data (all 12 of them) are posted on the Ecotrons thread. Because the Transfer Efficiency graphs are probably similar to any performance 2T with a few adjustments to the rpm points the numbers may make a useful start to any 2T Alpha-N map project.

Once I started to understand how EFI worked it was relatively easy to get full power runs but it was quite hard to develop a map that is good for part throttle and transition from full throttle to closed and back to open again. This has been the biggest issue holding me back from having a track ready EFI bike.

Now to map it all out.

Simple in XL

Attachment 320596

Attachment 320597

Job done, now to see if it actually works.

[Muciek]

Wobbly (or anyone with experience on oils) any thoughts on Penrite oils for 2T compared with other stuff for racing purposes?

[JanBros]

Look it up on youtube, Aria mud run.

great fun

the things men invent to do with motorcycles

[1948rod]

re the offsetting the cylinder. does this give a straighter push on the crank as in a tangent if done to excess. if this is so the effective stroke [crank pin to crank center line] during the power stroke which is where the power comes from. the piston to rod angle would be reduced giving less friction. no idea if this is true just a thought from a humble follower of this great forum.

[wobbly]

Quote " if this is so the effective stroke [crank pin to crank center line] during the power stroke which is where the power comes from ".
What power - as far as we know to date,there is no proven power to be had with DeSaxe cylinder or piston offset.
Anything gained from a more linear push on the rod/or less friction is seriously affected by non optimal port timing asymmetry.

[adegnes]

Now that my new bike is nearly ready I need to develop a new Alpha-N fuel injection map. The axis's of an Alpha-N map is throttle position TPS and RPM. The steps between cells need to be in even steps. That is not even RPM or TPS steps but even changes in engine load.

"Torque" is largely related to the motors Trapping Efficiency of the air passing through it.

"Delivery Ratio" is everything when it comes to quantifying airflow through a two stroke motor and it is the air flow that needs fuel added to it in the correct proportions. Trapping Efficiency is the measure of how much of this air/fuel is trapped to be com-busted.

Initially I thought changes in Torque could be used to represent changes in engine load and could be used for developing a fuel injection map. Well that might be Ok for a four stroke but now that I have tried that approach I now think that Delivery Ratio is the more suitable measure for developing a two stroke map.

Air flow (Delivery Ratio) through a throttle is not linear. The greatest changes happen between 20 - 40% throttle opening.



The first requirement is to find the throttle openings that corresponds to even Delivery Ratio (air flow) steps.



Then I modeled these throttle openings in EngMod2T and got a reasonable correlation and reasonably even layer of Transfer Efficiency steps in the power region of the simulation.

This information at each TPS position and RPM point should make a handy start for developing the new map.

The rest of the simulation data (all 12 of them) are posted on the Ecotrons thread. Because the Transfer Efficiency graphs are probably similar to any performance 2T with a few adjustments to the rpm points the numbers may make a useful start to any 2T Alpha-N map project.

Great work!

[marsheng]

re the offsetting the cylinder. does this give a straighter push on the crank as in a tangent if done to excess. if this is so the effective stroke [crank pin to crank center line] during the power stroke which is where the power comes from. the piston to rod angle would be reduced giving less friction.

Here is quite a good explanation. More offset more vibration.

https://rideapart.com/articles/free-...ders-explained

[TZ350]

This is what my new Alpha-N map looks like. Pretty pleasing to see the map is mostly even steps in the 7,000rpm and above area.

WorkFile Map 39A 16-03-16 RAM_MAP_LdTp_Tps_N.xls

And the spread sheet with the original EngMod simulated transfer ratio data and the calculations for developing the new Alpha-N map.

Hopefully get to try it on the dyno soon.

[bucketracer]

Interesting to see what can be done with EngMod. Looking forward to seeing how it turns out, should be good ....

[sispeed]

Found this due to a search for other stuff.
http://www.evanscoolant.com/faq/general-questions/
If you use this would it isn't a watercooled engine

[Frits Overmars]

Found this due to a search for other stuff.
http://www.evanscoolant.com/faq/general-questions/
If you use this would it isn't a watercooled engine

It would also be illegal in most forms of circuit racing, the reason being that spilled water will only temporarily wet the track but spilled non-water coolants will make the track unusable for days.

[sispeed]

Makes sense not to use it on a track.
Was more of a joke for the Bucket aircooled rule

[Flettner]

Turns out the F1 was all 4 strokes, so had some time to help Neil with the design. No charge.

Yes that's it right there.

Somone has to have a serious go at the mud run don't they? AND it has to be a loud high powered twostroke.
Rurual NZ, you should see the kids afterwards all playing in the mud, the fun we had

[TZ350]

Mud fun ... yum ...