MXA 2-stroke carb vs FI face-off on 2027 TM 300s

Its great that Tm offer both versions for the buyer….with more R&D the FI will get better settings and eventually be a better bike for most owners….I”ve had several KTM carbed 300”s, jetting was always a moving target depending on multiple factors…woods, Mx, temperature, elevation ect….I have had my FI 300SX in NY, Colorado and Florida…the FI performs flawlessly, from MX to single track….but yes, I did have it reflashed and it was not cheap compared to changing jets😂

Having owned dozens of carbed 2-stroke bikes over the years and currently owning a 2025 KTM 300SX,  my observation is that some carbs are better than others. The best carburetors are probably a bit better than KTM's current FI setup.  The worst carbs a much, much worse than FI. For example, the Keihin PWK is practically magic, the older Keihin PJ is good, but much more sensitive to elevation and such, and Lectron's are pretty good, but not on par with the PWK.  The Mikuni TMX is a better paper weight than a carb. 

Carb supremacy. 

I had a mikuni on my 17 250, after some playing around it was awesome. For years only minor pilot adjustments and beyond that it was perfect. I spent probably about 6 years telling everyone it was them not being able to jet a bike that was wrong with the mikuni 

The exact same spec mikuni on my 19 300 was awful and no matter what I did with it I struggled to get it right. Put a keihin on and it was amazing first try. Slightly humbled me I'll admit, seems to be a lottery if the mikunis will work or not

That's the issue, the Mikuni TMX just needed one simple mod to work. I took mine and removed the X from the intake bell. Now it works perfect on my BRP.

Test was not apples to oranges- they could tweak the very effective and ancient long body, flex about it…yet shoulder shrug the FI bike. Why on earth would an FI bike be provided and not have the provision to map differently? That should have been provided for this test IMO- It just makes the bike look bad, sort of cutting off your nose to spite your face. Then the one guy says “all nine” sprocket bolts with a twinge of sarcasm, clearly doesn’t under the reasoning behind them. 

The TM300 is a great bike, raced them for 5 years , its a little 500, not a big 250. 

Wish i had kept mine, but ended up with a 350 Husky, which is almost as good , as a 60+ rider, if you dont own one of these you are missing out. 

Ive had 6 KTM 250sx's over the years, it was a sad day when they changed to the Mikuni... Still not as bad as the HORRID TPI, both my 300sx TBI and now 250sx TBI have been great, but I still miss a well tuned Keihin...

100%

The Mikuni is much maligned, but if tuned right, which admittedly can be difficult, they do outperform the Keihin. There's a reason many factory teams ran them.

The other perspective would be, the FI bike with tuning software costs $600 extra.. The carb bike is stronger with $40 worth of brass thrown at it.

Apples to apples = same money spent, or apples to apples = both tuned? It depends on which one you wanr to see win and you can’t please everyone.

To me, it sounds like the goal would be to try to get the FI bike to run more like the carb bike.

I disagree, but that’s ok. If you tune one, should tune the other to be fair. The cost is what it is, bigger question is why would they even send it without the cable? Definitely a slanted review. 

Tm 300 carb vs ktm 300 sx tbi

Would be interesting.

2 Blokes : one faster on the FI, one faster on the Carb'd bike.

So, even stevens.

Only $100 difference in the price - surprising.

Now, that (they say) with the FI you need a $500  'cord ' ( cripes, it's seems it's got to be more than a 'cord' that's needed) would bring it closer to the price difference I expect.

It all may be down to FI tech becoming more affordable, and /or Carbs becoming more expensive, given there must be far fewer being made now?

That the TM people did not have said 'cord' and whatever is needed there, is quite strange. Seems quite the mistake.

Anyway, good to see they have the option of either. I've had a fair bit to do with TMs, and, hold them in high esteem - especially the frame build quality. Not to mention the ( pretty much unneeded) fins on the casings - I've seen grown men having a quiet cry after damaging them in  a prang - I would too!

It’s a diagnostic cable for resetting the PV, trouble shooting, mapping changes, etc, it requires a windows based laptop(most have those). People squawk at something like that but have no issue spending money on a useless exhaust or fancy levers. People are strange, but so it goes.

I would imagine it has some kind of software to be able to communicate.

I want to make it clear : I have No problem with FI being more expensive , I really do expect it to be, over the humble carburettor.

And, if I were to get an FI bike, I'd stump up for the cost of 'cords' / controllers to be able to adjust things.

As, I'd  see it as being necessary. to have available to me.

However, OEM companies that make FI bikes, should , I feel, make whatever is required affordable , and Not Go The Gouge on said things. 

I'm really out of the loop on what different manufacturers have as Adjustable Interfaces with FI, and the costs , if any, are involved.  I have the thought that perhaps Yamaha have the easiest set up, with it being of no extra cost to owners? But, buggered if I know the truth of the various set ups.

Now, I understand, with bikes that are restricted in their tunability by whatever  Countries Rules and Regulations are with On Road / Rego -able / Plateable models - That side of things can really limit  changes, and, they often have to leave it to the Aftermarket for FI tuning options. That episode with the RMX450 and whatever was the plug in-able thingo showed how getting the attention of ' The Authorities ', can really lead to "consequences".

When they tested the TM in the magazine, they said the KTM had more power. 
From memory: they could only really praise the TM for being boutique and customisable from the factory*. I found it a bit of a disappointing result as I was considering a TM300 (enduro) st the time.

*Not lighter, better handling, or more powerful. 
But again from memory: I think they did acknowledge the reason, and advantage for the 9 sprocket bolts. 

They also went down 1 tooth on the front and up 2 teeth on the rear of the FI BIKE. That’s a huge difference.