ESE's works engine tuner

[Tim Ey]

Crossing fingers! There's 3mm added to the bore in the model for casting.

In radius or diameter? In diameter it is not enough. I did the same and needed to weld.

198ex + a little bevel
130A
132B/C
90mm rod, 39.3mm stroke.
STA matched in Engmod, lots of area.
.

Matched sta or real study?
Since those are the RSA timings, I would think it will behave well at the same pistonspeed. That would be 17000rpm...

I think I would rather start at
A 126
B/C 124
MAIN 193
AUX 178
With a peak at 14500 and overrev to 16000

Grinding higher is easier than grinding down.

[adegnes]

Alex,

Re your concerns re possible frictional drag of the disk valve. I agree with others (Wos) that this might be small, given the right material matching. However, I am aware of these breaking (in karts) occasionally and your experience.

So, how about eliminating the friction entirely? Instead of allowing the valve to “float” axially within the valve housing (presumably bearing on either side of the valve depending on the pressure differential between the crankcase and the intake system), fix the valve to the crankshaft so it cannot move axially. Then adjust the side clearances between the disk and the cover, such that the disk cannot contact (drag) the cover. Obviously to do this will require allowance for crank float and thermal expansion of the cases etc. To make you feel better, a more solid disk, eg 2 mm steel to remove and doubt about bending.

Yes, yes, I know there will be leakage, loss of sharp timing and maybe even hard to start etc, but does this matter? Remember 24/7 induction, open all the time, making any such leakage relatively minor.

Keep up the 2 stroke passion.

Thanks Ken, that is worth a try.
I'll keep to the tried and true with my new engine for now, and experiment with stuff like that in parallel.
I've always wanted to try servo driven RV + rotary encoder on crank. Don't think I'm the only one who's had that idea, but I've never seen it done.

Speaking of experimental stuff.
I'm playing around with a brute force concept v2.
A pile driver diesel hammer/sleeve valve hybrid.

Maybe I should just go opposed piston uniflow.
Here's Tri-Mac Speedsters Supercharged 100cc opposed piston uniflow two stroke. Two Lifan engines with a custom cylinder in between. They're talking about it in my Bonneville video.

[adegnes]

In radius or diameter? In diameter it is not enough. I did the same and needed to weld.



Matched sta or real study?
Since those are the RSA timings, I would think it will behave well at the same pistonspeed. That would be 17000rpm...

I think I would rather start at
A 126
B/C 124
MAIN 193
AUX 178
With a peak at 14500 and overrev to 16000

Grinding higher is easier than grinding down.

3mm radius, 34mm bore.
In my castings I made separate small feeders for all the bridges, then a big feeder for those feeders.

Current engine in the landspeed bike has a ported iame m50 cylinder with the same timings/angles, but not as much area. It works well, especially after I made a new pipe for it, the old pipe was made from pieces of a shovel, and some scooter pipe pieces.
Made 18rwhp with that old pipe, new pipe should give considerably more.
But.
The crank in it has too small webs, not enough material around the crank pin. Made even worse by the outer edges being beveled, and balancing holes too close. All available cranks seem to have the same issues.
My testing up until this year when I revived it(bike has been in the US for 5yrs)has been with those cranks running continuously in and out of true.
No wonder my fuel was foaming... Also explains why it ate two big end bearings for no apparent reason.
Welding the crank pin helped a lot.
It also suffers from high wear. Short 75mm rod, and cast iron bore.
I think piston slap is what caused it to pinch the ringland a few times, probably in combination with touching the head caused by the eccentric crank.

The reason for building a new engine is to fix all this stuff.
Plated bore vs cast iron, 90mm rod vs 75mm, beefier crank, and more port area as I'm not working within the confines of an existing cylinder.

[wobbly]

Tim Ey , but with a square bore/stroke and the same piston speed the 50cc engine will be operating at its most efficient at 17,000.
The only reason I would see that going down to 14500 rpm and an Ex port at 193* would be to accommodate a crap gear ratio set and needing a much wider power band
for say a Bucket racer - thats all been done before , and would never break any sort of records.
LSR has none of those limitations and needs as much peak power and overev as is possible, so it drops back into peak torque for the final gearchange with max aero drag.
Remember Power = T X RPM , reving the thing to its mechanical piston speed capability ,as long as the STA numbers match at that rpm, automatically approaches the theoretical maximum achievable

[adegnes]

Tim Ey , but with a square bore/stroke and the same piston speed the 50cc engine will be operating at its most efficient at 17,000.
The only reason I would see that going down to 14500 rpm and an Ex port at 193* would be to accommodate a crap gear ratio set and needing a much wider power band
for say a Bucket racer - thats all been done before , and would never break any sort of records.
LSR has none of those limitations and needs as much peak power and overev as is possible, so it drops back into peak torque for the final gearchange with max aero drag.
Remember Power = T X RPM , reving the thing to its mechanical piston speed capability ,as long as the STA numbers match at that rpm, automatically approaches the theoretical maximum achievable

Exactly ��
I'm running a variator and don't need the overev, just peak.
Said variator worked flawlessly out there, rock steady rpm.
The challenge is setting it right for a run.
We saw variations in relative density altitude(from under 5000ft to almost 9000ft throughout a day.
At high RAD(and jetted right) there's more power, and the variator will rev higher with the same weights/spring tension, at low there's the opposite.
Need a good table of what's needed, or a good automatic correction system.

I'm debating if I want to run methanol/nitro, or run gas through the carb and have a separate nitromethane injection system.
Did anyone ever try injecting nitromethane alongside a carb already tuned well on gas? No extra air, just the nitro. I know Rob has mentioned wanting to try a few times.

[wobbly]

My first reaction to the huge Density Altitude variations is that a Lectron is affected by this less than 1/2 a normal carb.
And several guys running Pikes Peak have used a simple hand operated lever to adjust a screw in PJ and watched the EGT during the run to keep it on the money.
But a way cleverer way is that used by Tillotson for their pumper carbs - they use a servo setup from the RC car world with either +/- on board buttons or even remote control for
the screw adjusters.
Even one step cleverer again would be to use the 0-5V RAD output from a digital weather station , programmed thru an Arduino or Raspberry device to auto correct the real time EGT input by controlling
the PJ servo on top of the carb.

[Grumph]

We seem to have come a long way from Hugh Anderson riding the works Suzukis using a combination of throttle and air lever...

Get it right and it would last a TT. Wrong and you're out

[F5 Dave]

I was going to write., satellite wifi link , connect egt, pj, det sensor, 6 axis IMU, pornhub, gambling account, bitcoin wallet, and finally throttle control to chat- gbt so it can decide and you aren't tempted to Pussy Out when you encounter a sidewind, loss of traction, or braking marker.

[adegnes]

I was going to write., satellite wifi link , connect egt, pj, det sensor, 6 axis IMU, pornhub, gambling account, bitcoin wallet, and finally throttle control to chat- gbt so it can decide and you aren't tempted to Pussy Out when you encounter a sidewind, loss of traction, or braking marker.

😂 Travis would appreciate chat-gpt serving him some porn.


If nitromethane injection alongside a carb running gas works then fueling won't be a problem. On the fly variator tuning is probably necessary though, I'll leave that to the satellite link.

[diesel pig]

Rereading my posts on your time on the salt. I now realize I was coming across happy with your speed but what I was really happy about was you had done your first run on the salt (everything I have read about people's run on the salt was it was like running on nothing else one will run on ever) and now you could concentrate on your speed. Now my two cents on your intake thoughts, I think you should first make use of the fantastic information on this and other sites to build the best conventional 2T you can whether that is reed or disc for your speed runs. But ultimately I think the way you should go would be Frits's 24/7 inlet system but Free jazz* on that in between building a good conventional motor!

*I love that term and will use it where ever I can.

[Condyn]

With a CVT front side right before peak, peak, and a small bit of over rev are still important. I have made hundreds of tests on my cvt drag snowmobile and made and tested many pipe designs. The difference is my pipe temp never stabilizes in 500 feet where yours should be. Regardless, It is far more forgiving for your pipe to be designed to better handle even minuscule load changes, whether that be a bump in the track, or a slight elevation change, or in your case a gust of wind. The effect on peak is virtually non existent if done right. The clutch will do its job to hold rpm steady, but there is always going to be a small amount of load change. When watching DA, Knowing what your cvt needs is equally important as jet. Worse air, no power, less weight, less jet, slow ET/MPH etc. It will take a lot of testing time to figure out a scale so you know what to do. Once on your cherished run, there are curse words yelled when you know it is a waste of time because you have no rpm. Jet obviously has to be optimized before anything. It is a big circle of confusion because more clutch weight creates its own need for more fuel, so it compounds itself as the air gets better or worse.

[adegnes]

Here's the piston and plug from the landspeed bike after a run where it seized just 10s off the line.
Lean on Methanol/Nitro. You can see how the ground strap, center electrode, and piston dome has started melting. Good thing the crown grew too much and it locked up before we had alu dust everywhere.
Mixture seemed ok on our roller in the pits, obviously it wasn't. Did actually sound lean before take off, should have aborted.

[Gradella23]

Here's the piston and plug from the landspeed bike after a run where it seized just 10s off the line.
Lean on Methanol/Nitro. You can see how the ground strap, center electrode, and piston dome has started melting. Good thing the crown grew too much and it locked up before we had alu dust everywhere.
Mixture seemed ok on our roller in the pits, obviously it wasn't. Did actually sound lean before take off, should have aborted.

hello, what kind of piston is that? which compression heigth? I'm desperate for light and well manifactured 39,96 pistons

[adegnes]

hello, what kind of piston is that? which compression heigth? I'm desperate for light and well manifactured 39,96 pistons

Barikit PE-65, 0.8mm ring, ring gap centered over C port, 12mm wrist pin.
24.5mm compression height, 100mm dome radius.
Emot Racing has them sometimes, VRM in Sweden too. VRM just got more in stock.

[Gradella23]

Barikit PE-65, 0.8mm ring, ring gap centered over C port, 12mm wrist pin.
24.5mm compression height, 100mm dome radius.
Emot Racing has them sometimes, VRM in Sweden too. VRM just got more in stock.

same as me ahah, got it from martijn at emot. it's just a little bit heavy at 77g (with pin, clips and all).