2 speed tranny helps a lot with low end power.. just saying.. yes still fast and fun to drive but offroad has 1 gear.. you have your view and i have mine.. neither are right or wrong we just believe what we believe. i just think this world is becoming really crazy everywhere.. lots of sick and twisted people.. governments need to uphold the laws and stick to them.. but then you would have to have a government that actually follows their guidelines. as you eu guys know the usa is the laughing stock of the world for government right now.. but in the long run we all need to do our part to keep this great hobby going..

True!
But when we made the step also many people were whining about slow and a loss of power. All the complainers had totaly no experience running on 16%. I am pretty sure this is the same story that is happening now with the offroad, many people complaining w/o even tested/experienced it. I think if you ask guys like Drale Lutz Falken etc if they ever did run 20 or 16% to get a better milage then I think some will admit it.
I know from our 25% era that one Dutch guy who did win a national race and then found out he was using 16%. Beside that, in the onroad the use of 20 or 16% was well done if they need to run a qualification w/o a fuel stop.

i get it but being that low it might have more effect on offroad. i personally just switched to 25/8 fuel and yes agree more run time with the same power now drop 10 more percent and adjust motor shims will bottom end be the same? we will see but i would expect less bottom end.. then clutching comes in to effect.. lots of little things to see how it plays out.. in the end the crappy people that do bad things to get these regulations needed are the ones to blame in the end.. crazy world..

Thanks guys for your statements 👍🏻

So if i get this right all the onroad racers do to go from 25 to 16 % nitrofuel is just tweaking the needels a bit and maybe change to a hotter glowplug?

Here is a part of the EFRA fuel letter written by Mr Comes.

The truth is that switching suddenly to a 16% is complicated (we already saw what happened with 1:8 I.C. Track), but going to 12% can cause breakdowns everywhere, having to buy new engines designed for that type of Nitromethane content.

i agree with roelof that our engines may work flawlessly with different fuel, an i see not why there should be a breakdown!

But what breakdowns Mr. Comes is talking about?

People fear of loosing the excitement of going powerful fast. I have runned many classes, even with a simple Nikko car we had a lot of fun racing all with equal low power.
Going for a hotter plug will do something but the best advise is to take out a shim, lower the head by 0.05 or 0.1mm because with the smaller combustion room a less power combustion will bring back some power compared with no compression change.

In a large FB nitro bashers group people are screaming about a dying nitro hobby and how stupid the EU is but no one ever tryed 16% The stupidity is even bigger when the mods also say it is stupid and you should fight against it. Face it, there is no way to fight against it. Yes, it will affect the bashers too who like to run as much nitro as possible but you can be mad about it or you can just advise the right way what to do to run on 16%.

Here a guy who tryed to explain it all but will not face the 16% change, he will try to postpone as long as possible. But look the reactions under the video. And this rule was already known 2 years ago.... (also the reason why the EFRA did not want to change back to 25% with a proposal at the 2019 AGM)

I snooped around a bit more.... why does this stuff have to be so hidden away? Incredibly hard to find concrete info on it.
Anyways, for the one and a half german people reading this: they specifically mentioned that they will not implement a system to get a license here. Reason being: so they can better enforce the rules. Thanks for nothing I guess.

See what happens without Tranai.

Hi All, long time stalker, first time poster in this sub.
Perhaps I can offer some insight here. (my user name might be a clue) I also raced RC nitro powerboats, and in the 3.5cc hydroplane (FSRH) class I ran 60% nitro in my Novarossi powered hydroplane's. And at much tighter squish clearance that what I run in my rc cars. Why? Simple answer =Torque. Nitromethane is liquid torque. Hydroplanes are direct drive, no gearbox and no clutch, and hydroplanes are very hard to get up on plane without torque - and fast props have a lot of pitch. In a car it would be like trying to use the smallest spur and the largest pinion, with the softest clutch known to man - the thing just isn't going to get on pipe without that liquid torque and tight squish helping. Plus, no fuel tank capacity rules, if I need longer run time we use a bigger tank. for perspective 230ml (8oz) tank is just enough fuel for about 2 minutes of Wide Open throttle running on 60% in a 3.5cc engine.

I've spent a few years recently playing with 16% nitro in 1/8 onroad GT class (in case my friend who I help out with engine stuff decided to go to the IFMAR GT worlds). Here is what I've found;
Removing head shims and going to a hotter glow plug works OK for 16% to raise compression ratio for the higher percentage of methanol. However, it introduces another variable that is super important in a 2 stroke engine - the squish clearance. A tighter squish clearance can effect top end rpm and alter detonation point on the tune. If you really want to know why -look up MSV or Maximum Squish Velocity. The optimal MSV for nitro is different for methanol and different again for gasoline.
What also worked is maintaining the same squish clearance, but reducing the bowl volume of the combustion chamber. This requires a lathe if a lower volume head is not available. I'd dare say engine manufacturers will start making motors and heads to suit the lower nitro content over time.
I have found it most beneficial to also alter gearing and then test other pipes and headers when dropping down in nitro % from 25 to 16. That pipe that is killer on 25% may not be as fast on 16% at track XYZ as a pipe that wasn't so great on 25% and a gearing change.... Getting detonation, motor tune window is really hard to hit, or motor running way hotter? (30deg C+ more) Try a different pipe and header length. Nothing "bolt on" has a greater impact on power curve, rpm like finding the best pipe / pipe length.

Cheers,
Tim

I now had the opportunity to test fuel with 12%. It seems you were right. Adjustment and idling are not a problem. The slightly less power at low speeds can be adjusted with clutch, transmission and venturi.

The crankshafts and exhaustport can also be modified to make more torqueso the differences is even smaller 😊

A quick question, how do we know that we have the right fuel?
I have seen 16%, 16EU, 12% and so on.
Which fuel brands are producing the correct nitro blend?

All fuel companies selling fuel within europe must comply to the new EU rule. I believe Runnertime and Energy are calling it 16% EU. 12% would also be fine becaause that is about the same as 16% by weight.

But you can visit the brands product pages to find out the part number of the EU spec fuel.