Great to hear that progress is coming on nicely, it seems like you and Alex ('2 Stroke Stuffing' channel * ) have had a lot to work out of late. But, as always, 🤞 to the both of you achieving our goals! Looking forward to the speed test runs too! I take it you sorted the 'Potential' rear tyre/dyno rub issue? 😏 * For anyone not in the know, Alex is a guy who has hand built a 50cc 2 stroke motor and is trying to make the most powerful motor for land speed attempt. If successful, it'll be a supercharged Nitro run 50cc. He HAS had 24ish BHP, but is working on a redesign, go check him out as well as this fine gent here! 👍 😎🇬🇧

The timing tells you a lot about the pipe length to port timing relationship - and some about the head - as it's all tied in together. In my opinion - this is telling you the pipe is a little short for the port. Im not a pipe expert like some people - but adding a little length to your belly would be an easy start to this theory - and see if you can find your peak torque at 10-13 deg timing rather than 22 ish. If you add length and reduce timing - you *might* find a better combo. Addtionally - if you add compression it will be similar to more timing. What the timing really does is alter pipe temp. All bulk power is made via the pipe's influence on the egine - so what we often 'have happen" is we tune variables such that our engine is making the pipe happiest to trap the most air. Nice work - keep plugging away!

8:30 You are not dealing with a huge increase when you look at the raw numbers but that is partly because the 'before' and 'after' numbers are both fairly small, its still a 4% increase and that is worth having.

Really good, methodical, testing. 👍

Cheers for the intel. Planning on getting an HPI digital ignition for my 2T Suzuki 68cc. Appears the HPI software is a similar design, so this helps understand the concept. Still learning by myself. Good luck with your 100mph goal, friend. I'm chasing 100kmph on the 68cc, and I'm nearly there (94kmph).

Very nice!! The boat looks much more planted with the bigger props and you didn't lose any speed

Great video thanks keep them coming

Looking forward to your flow test video. That will be interesting.

great job lad keep at it im sure ul get there

Good video - and like the trial and error approach for the timing curve versus hp curve😊

Dude Please don't pay any attention to Derek Harris, he believes that the reason for retarding the ignition at high RPM is just to create heat in the pipe, You can see your 10 degree flat line test sent the pipe temperature through the roof but the power curve was crap! He thinks that the VE of the engine is not a factor in determining what the timing needs to be at any point in time. The real 'icing on the cake' for me was when he stated in a post that peak cylinder pressure should occur at TDC, this is total nonsense, the likes of Ricardo Developments worked this out years ago, peak cylinder pressure needs to occur between 14-20 degrees ATDC. 7:05 Your timing 'curves' make perfect sense, you can see how the timing needs to advance as the revs rise up to around 8k RPM, this is because the RPM is going up but the VE of the engine is still fairly poor, (the engine is not 'on the pipe'), in this state the timing needs to advance to give enough time for the flame front to create peak pressure at 14-20 degrees ATDC. Then as the engine comes on the pipe the VE starts going up and up, the initial cylinder pressure before the plug fires is going up as the pipe and intake 'resonate' harder and harder, the initial cylinder pressure has a great bearing on the flame speed so the timing has to start retarding to compensate for this. A.G Bells book on 2 strokes explains why a 2 stroke runs an advance curve until the engine is making decent power and then it runs a retard curve once its in the powerband, its all to do with the VE! (The aim is ALWAYS to get peak cylinder pressure at the right point in degrees ATDC)

The 15 degree peak power recommendation is meant for some crazy hp engines which are far from our typical moped-base tuning candidates. The burn rate gets faster the more mixture you can get crammed in the chamber and the advance must be less, but it takes a lot to make the cylinder that good. I have also found that 18-20 degrees at peak power is quite good. I have tested removing the lower piston ring a couple of times and it did not seem to have any negative effect at all even though the groove is open. The engine sounded more eager to rev but at that time I didn't have a dyno so the result is subjective 😁Some guys have plugged the groove with a spring pin. Another technique I heard of is to heat the lower ring red hot in a mandrel so it loses the springiness and just rides in there with minimal friction.

Thanks

I have an RD400 and put an ignition that had a curve in it and I was stunned at how much more power it made. Problem was it had the tiniest lightest flywheel.. it weighed nothing and I hated the way it make the bike feel.. and having to have a high idle just to stop it from stalling was annoying. I splurged and put in a VAPE and it has a large hefty flywheel and the bike idles and feels amazing.. This winter i will purchase the controller module so I can program in a safe curve and get all the torque I experienced, back.

You need to take a leaf out of a certain Norwegian 2T dude's book, and leave the best bit to the beginning of the next video, and leave on a cliffhanger. That dude has figured out how the algorithm works 😂 as for tuning, all i ever learned is that all the thinks we thought that helps actually does nothing. Best bang for buck is in port timing, pipes and lots of revs. Perhaps compression and ignition timing afterwards 🤔

It would be nice to have some plugs pics after the runs with different timings

have you read "2 stroke performance tuning by A Graham Bell" this is pretty much my bible when building up an engine. using more premix will often gain power (up to a point), better lubrication, better ring sealing etc, what fuel are you using? loving the project, vaguely remember reading of this many moons ago. Subscribed ;)

New to your channel. Great stuff. I ran a Suzuki RGV 250 at Land Speed events in Australia for a few years and tuning a smoker for sustained Wide Open Throttle is an "interesting" challenge. What petrol/fuel are you running?

I'm eating a hamburger while watching this!

Nice work! In my tzr250 engine as i´ve converted to fuelinjection i just looked at how the curves are looking like in a highperformance twostroke, and saw that 'underneeth' where the pipe breathes they can take a lot of ignition, i´m running mine on E85 and have ~35 degrees down low, i´m running 20-21degrees at idle. Up top where the pipe is working i am comparing it to an boosted 4stroke engine, when the boost hits one need to lower the ignition. So, by this i´m saying that you can probably run much higher down low.(if needed) I honestly already ran this curve i programmed into maxxecu in my ignitech system before. But a thing to consider is that twostrokes is very sensitive, the rpms after are depending on the rpms before. If wanting a huge powerband one can sacrifice a couple of newtonmeters to gain some up top(pipe temp)

Dave, what was the EGT when your engine was running timing that gave the best peak power and how does that compare to the flat 10 degree run? I'm going to 'stick my neck out' here! I bet it was no higher and possibly lower on the best power run compared to the 10 degree run.

Try a cone in cone on the baffle cone, put a spring on the stinger so you can adjust the tuned length of the rear cone and fine tune the pipe at different rpm.

Supposw compression ratio between orher peoples and yours mean diffrent timing

Ceramic coat the piston top and combustion chamber, also the expansion chamber. On V8s coated headers reduce heat immensely. Should retain the heat in the combustion gases and not the engine and pipe.

Sir, I need such a help. I want to ask about the port of such a cylinder, how can we increase the speed from its port. Please help me. Please tell me.

Hello sir, greetings from Malaysia, I have some issues with the spark plug, the ring and the ground electrod were dark brown, but the electrode shows white colour. Please help

What fuel are you using? Would a higher octane help prevent detonation?

Can someone recommend a cdi for tuning

Is Horse Power Race Development, linked to Horse Power Ignitions in any way?

start the ignition curve tapering off(retarding) of your test curves a little earlier. You need to start building heat in the pipe just a tad bit sooner in your dyno pulls.

Here to let you know the thumbnail worked :D

Hey that's me!!!

What’s causing the 100 mph barrier is power/ weight and wind your trying to push . Just ride behind a car

I see you're mod your intake, next time try install an induction tube in your bike. The simplest is copy a Suzuki SIPC, you just need 2 metres of a 10mm hose. Please try it.

bigger carb get more fuel in it

Fix your links

SHIT! 😞

Dude it’s not a moped! Stop

Lots of good testing and technical appraisal. However, looking at the photos in the magazine, there might be something you have overlooked… The AR they used was green (and everyone knows the green Kwaks are the fastest). Time to get the rattle cans out!