Thanks folks, that makes sense now. X30 has limited play via rule set, OK has greater latitude.
So, you dont need to buy a bunch of engimes to take biits from each. You could simply mess with wider tolerances and that can be done via builder as opposed to in the manu process.
This is the on-paper consensus of it all. In the end of the day, money wins whether it’s through part picking or machining and R&D. But, in theory, there’s an intersection point where one becomes cheaper than the other. All in theory.
If Im getting this correct, RPG (just as an example) wont piss off their engine partner by having to go to a different, faster engine. They can simply have engine built “better”.
They’re somewhat of an oddity, but actually yes. Everything they do is in-house on their building / tuning side for engines when it comes to X30s. They’ve probably got equipment to work with any manufacturer they want and actually do machining and manufacturing on their own, so they could jump ship. I’d imagine Vortex would support them heavily as they already do in KZ, and being the loyal troopers that they are, would run them and make them fast. They did with Danny in Vegas against a sea of TMs.
I’d say the argument is for the small teams. Teams of the MPG / Leading Edge / HRT / Mike Doty Racing that are independent – they may not have the backing to buy a pallet of engines to source a superstar motor, and they don’t have an in-house engine shop. But, they could go to 1 of the 6 (!) engine manufacturers and broker a deal for support to get good equipment. Whereas in a single-spec series, there is no support. Just the hope and expectation that the single manufacturer single-handedly levels the playing field by keeping tight tolerances and working with the series.
Just to make sure I have this right, x30 in skusa and Uspks is an example of the above. The builder can’t do much other than pair bits from multiple x30s to find the magic rocket engine?
Whereas OK the builder can, within a range, say for example, increase/decrease the cylinder bore or whatever?
This has me thinking about mah hero Ryan. He’s with the biggest team that has scale and connections. He probably has the “best” equipment they can come up with, which isn’t something that the independent, small(er) teams necessarily have access to/relationships for.
I’m guessing Ryan might be less dominant in a OK field against euro-farm teams with ginormous budgets and wealthy clients that can afford to pay builders top dollar for their best engines. I bet he’d still kick plenty of butt, tho, because you just can’t manufacture that kind of talent and drive.
In X30 you can still bore the cylinder and do a few things. I’m far from an expert on the differences of what you can and can’t do, but it’s not 100% hands off either.
Thanks. Yeah I’m clueless on all that and wasn’t sure that was an actual example of where a builder might look for “gains” so I appended it with “or whatever”. 
From the FIA Technical Regulations.
5.1.1 Modifications
The engine may be modified according to the modifications allowed
in the respective categories, but only within the dimensions listed in
the TR.
If modifications to the inside the engine are allowed, they may only
be carried out by the removal of material.
OK Specific
9.11.2 Modifications
All modifications to the inside of the homologated engine are
allowed, except:
- the stroke;
- the bore (outside the maximum limits);
- the connecting rod centreline;
- the number of transfer ducts and inlet ports in the cylinder and
crankcase;- the number of exhaust ports and ducts;
- the reed-valve box (dimensions and drawing);
- inserts in the crankcase and/or cylinder, except those for crankshaft bearings and attachments (drilled holes, dowels); and
- any surface treatment of the cylinder liner, including, but not limited
to, chemical treatment or the addition of a coating; and- any surface treatment of the crankshaft or conrod,
including, but not limited to, chemical treatment or the
addition of a coating, except if they are described in the
HF.
Restrictions set out in specific regulations must be respected.
All modifications to the outside of the homologated engine are
allowed, except:- the number of carburettors (mandatory use of one homologated
carburettor); and- the external appearance of the fitted engine.
The following are not considered to be modifications to the
appearance of the engine: trimming of the cooling connections,
modification of the colour of the parts and modification of the attachments (including but not limited to those of the carburettor, ignition
coil, exhaust, clutch or engine itself) provided that their homologated
position is not modified.
9.11.1 Engine characteristics
Direct drive water-cooled 125 cm3 single cylinder two-stroke reed
valve engine, with one cooling circuit for the crankcase, cylinder
and head.
Exhaust ports angles are measured at the level of the port edge, in
accordance with the method described in Appendix 3. They are
limited to:
OK/OK-N 194 ° maximum
OK-Junior 170 ° maximum
The combustion chamber volume is measured in accordance with the
method described in Appendix 2.
OK 9 cm³ minimum
OK-N 10 cm³ minimum
OK-Junior 12 cm3 minimum
The decompression valve, which is mandatory, must be fitted on top
of the cylinder head.
In OK, a specific monotype power valve is allowed. It must comply
with TD n° 2.8 and be homologated with the engine.
A maximum 4% of lubricant added to the fuel is allowed
example OK homologation from TM https://www.tmracing.it/en/download/homologation-125cc-ok-s-junior/?wpdmdl=17295&refresh=63b549bb690331672825275
and then there’s a few TDs with some specified limits etc… but outside stroke and (max) bore you can work on ports and that kind of thing
In X30 you categorically can’t remove material. This is the main difference.
This is pretty much spot on.
Fundamentally speaking, look at an X30 homologation / technical fiche, to be used by technical delegates at the end of a race to tech engines. It’s about 47 pages long.
It is virtually impossible to check for everything within a 3 hours window / engine.
You may understand the motivation for some to indeed farm engines to build a near perfect prototype from the best parts of each, when the stakes become high enough and the differences become increasingly smaller and smaller (Courtesy also of IAME’s excellent quality control). This obviously not even discussing the smarty pants that actually bypass the regulation in one way or another, precisely conscious of the fact that whatever they’ve done will not be checked/ found.
In my (personal) opinion, you funnel down into what could be an unfair competition whereby 1) you cannot have the best of the best 2) it becomes a necessity to rent engines from “builders”, which has an extremely substantial accrued cost over the course of a season.
The fundamental of having a relatively open rule set means that, technically, anyone skilled enough with time and knowledge can achieve a race wining engine from a standard box engine. It is exactly the same concept as in KZ, albeit with a much simpler platform as the entire gear train is eliminated (a source of heavy tuning in KZ)
The homologation period of the OK’Ns is 6 years (vs 3 for all others), done on purpose to promote stability and reduce cost.
Just to convey to my experience as someone who has driven X30 since 2012 when they brought it to the US, the differences in engines is pretty small. I’ve driven both “good” and “mid” engines from lots of builders and generally the difference was not big. I agree with @Felix_Rovelli that the “buying 20 engines to piece together one monster” is blown out of proportion in X30. There are people doing that because people with the money will do it regardless of what engine package they drive.
I also agree with @Simone_Perego that IAME’s QC is very good and the engine parity from the factory is pretty strong.
It will be interesting to see (if OK-N actually takes off here) whether teams are committed to one brand like factory efforts are, or if different engine packages will have advantages or disadvantages leading teams or privateers to own multiple engines like TaG did. Of course the performance variations won’t be nearly that big since these engines were designed to compete with each other, but surely there will be some kind of advantage or disadvantage with each package. Even if it is just reliability or build quality, you may see OTK teams on something other than Vortex.
It’s good to see what seems to be positivity regarding the class and potential for engine parity but just remember that regardless of parity, someone with enough money will always be finding ways to spend it. Unnecessary or not.
I think if people expect engine parity the class with be DOA. OK-N is designed to reward smart engine builders fundamentally. If engines get close that’s fine (as with the 100s), but it shouldn’t be a selling point as it’s a promise that can’t ever be guaranteed. It’s a marketing tactic that should be avoided at all costs.
It will be interesting to see how many talented engine tuners are still around.
In the UK at least it seemed like a lot of the good ones aged out (retired), or moved on to something else so that now there are a variety of engine builders and very few tuners.
Welstead tunes 100cc motors still. I’d like him to work on my latest acquisition - atomik AKV90 - if he wants to. A few others knock about as well. Some new talent coming in as well. Whether they could be bothered with OK-N is another matter.
It’s a shame, like you say, we have a lot of builders not many ‘tuners’. It’s taken a lot of colour and character from the sport in my view. I have a books worth of anecdotes from builders etc…
I understand that and I’m definitely interested in allowing tuners and builders some freedom. My point more being that if you are going to circuit A and engine package 1 is two-tenths quicker due to the layout and particulars of the circuit, what incentive is there for owners of other engine packages to even show up?
I’ll recount my experience in TaG where to contend for the championship, you needed a Sonik or Motori for long tracks, a Rotax for flowing tracks, and a Leopard for tight tracks. I only had a Leopard, so was out-gunned at New Castle by the more powerful engines, and then when we went to Tucson, the Rotax was 0.3 faster per lap, so we were forced to rent a Rotax for the weekend or settle for mid-pack. No amount of tuning was going to make the Leopard quicker than the Rotax just due to the layout of the circuit.
Now that being said, we did do quite well and landed on the podium a few times due to some absolutely hooked up chassis, perfectly dialed-in engines, and not to toot my own horn, but some excellent driving. I was on the podium at New Castle for the Grand Nationals with a 2-3 hp disadvantage to the Soniks and Motoris and 2nd in Daytona in the same scenario. But it’s a bit bittersweet to know you drove the wheels off of it and optimized everything you could but 2nd or 3rd was still the best possible result because another engine was just suited to the track better.
Hopefully the parity is good enough to not be discouraging at certain tracks. But as Stars just posted regarding OK-N, this is a premier class and will not be conducive to everyone’s budget, so I guess I’m not the target demo anymore anyway.
… because that’s the game.The game is to tune and develop the best engines, and drive the fastest way you can. That sporting ‘hybridrity’ is karting at its best. You need this competitive dissonance (sometimes racing rubbish gear) in the sport to make it a fuller experience, imo. I understand this is very complex to communicate to a market so entrenched in spec racing, but for me talk of parity is misleading… the objective is not parity for the competitor. The objective is to win. And you win by being a bloody good tuner combined with a bloody good driver.
I understand the comparisons to TaG, but as you know those engines were never designed to race together. TaG was a sticker plaster solution to the proliferation of ‘spec’ categories/products that conversely forced this Frankenstein stick-em-all-together option in the hope of close racing.
Stars’ statement is interesting. It demonstrates the lack of coherence surrounding the class as a concept
If anyone here exspects OKN enginesto be cheaper to run then X30 they are In for a surprise, and if they think engines are going to be equal they will have to rethink.
Rotax and X30 both haves pretty equal engines, a lot of the differences isin how people run them, there is always the talk about special parts, cylinder from xx year, bottom from xx year ect, In most cases its all In People’s head.
It’s not in their head. The differences are there.
The further expand on what Alan is saying. All those TAG engines were designed however the manufacturer felt like it and not to a common set of rules. Then add in the restriction on tuning and the only answer is different engines for different tracks.
In theory OK-N and to an extent FA and ICA before them got round this by tuning for circuits and not all that tuning involves machining. You can do a bit with relatively simple changes (gasket thickness etc).
I went KZ before the TM period that Alan mentions in the mid noughties but i do remember karting in these classes being a bit fad driven and if a vortex was winning everyone would jump on a vortex (it was the driver) or a comer was winning everyone would jump on a comer (it was the driver). Then suddenly a maxter would win because in reality the engines were all very close and it was the driver that still made the difference (admittedly with input from tuners).
Yeah TaG is not a great example of multi manufacturer because there were essentially no rules up to the point of homologation.
Essentially it ended up with a group of economy/spec development packages (PRD, Leopard, FR125) going up against the likes of the Sonik which was basically an ICA with a 54mm piston at first.
OK, KZ etc at least have a common ruleset with controls on ignition type, port timing, carb size, power valve etc.
There was nothing like this in TaG. Yes the engines homologated, but that was after the design was done, not before.
