ETZ 250 Inlet

[akirasan]

Has anyone replaced the inlet manifold for a shorter straighter one.

Any benefits ????

[DAVID THOMPSON]

mz was very good a tuning a 2 stroke i would not change anything
dave

[Blurredman]

The problem with that is perhaps location of the carburettor if anything, plus.. airbox..

I'm not sure it's entirely worth it, from carb to barrel, it's fairly straight.

[akirasan]

I understand your thoughts but has anyone done it on the road?
Racers do it and i have seen the reed conversion.

But has anyone on here actually done it for a road bike and how did it run?

[Puffs]

No doubt it has been done, also on the road. No, I have not done it.

As always, the most important question is: what do you want to achieve?

You probably found pics of my reed valve elsewhere on this forum; I wanted a broader, less peaky torque band, and that worked. But the carb stayed at exactly the same place, and there were no other mods to the excellent air filter system that the ETZ has. My focus was on usability in day-to-day work.

Shortening the inlet is part of tuning the engine to a higher RPM, in order to increase power output, but IMO you'll end-up with a more nervous engine. Surely quicker (if you get it right, at least), but also quicker to break-down, quicker to the pump, and more difficult to ride (continuously shifting to keep it in a narrow powerband). You'll have to loose the airbox & the rest of the standard inlet tract, and modify that too. Should also include modifying port timings & a tuned expansion exhaust. Racer territory.

Also, I understand that for a tuned inlet length it doesn't matter all that much where the carb sits in the inlet tract; it's the total length that matters.

Anyway, please give it a try & let us know what you find.