KZ10C "TUNED VERSION" BY TM RACING

Max Bernardi

03 October 2018

TYPE
Like most kart engines on the market, the KZ10c is a 2-S. 4-stroke engines are still a small niche.

125 cc

DISPLACEMENT
125 cc has been the standard for some time now, while in the past it used to be 100 cc

PUSH

START
Push-mode as in all KZ engines, with hand-release clutch and neutral to 2nd gear shifting

GEARBOX

TRANSMISSION
The KZ10C belongs to the gearbox “family” of karting engines.
It has a 6 gear manual transmission.

HOMOLOGATION
Certified under KZ homologation, valid for the next 9 years, beginning in 2016

Having a "tuned" engine is every kart enthusiast’s dream. It’s why there are so many tuners to turn to in order to improve performance. With its KZ10C model for shifter classes, TM Racing offers an "optimised" version directly from the maker".

"It's about working manually, grinding and milling small details that, together, make the difference. If we want to make a comparison, we can say that the difference between a tuned engine and a standard unit is the same as the difference between a tuned piano and one that isn't". These are the words of Franco Drudi, works tuner of the Pesaro-based manufacturer: no one knows the details of the changes that the crankcase and the cylinder undergo better than him.
Firstly, however, let's take a step back and introduce the KZ10C for those know little about it. It is the latest version of the KZ10 series that has been a stalwart in the KZ classes for years, boasting three world titles (Jorrit Pex in 2015 and Paolo De Conto in 2016 and 2017).
The KZ10C continues the winning tradition by making small improvements. For example, compared to the previous "B" version, there are differences in the inclination of the crankcase and the cylinder, including the reed valve pack and its attachment; differences in the shape and the structure of the cylinder head; in the transfer ducts; in the internal crankcase intake chambers; in the clutch cover and in the muffler.

The KZ10C engine, TM Racing’s flagship product for the shifter classes

All the modifications made to the KZ10C have been analysed in detail in TKART Magazine. As mentioned, this article will focus on the work done only on the "tuned" version directly by TM.
Starting from the cylinder, a significant amount of work is done on squaring the ports. In fact, when the chromium deposits, it tends to close the ports, decreasing their size and also causing a reduction in the radius of the angle. The aims of the work is to remove excess chromium: we are talking about 3/4 tenths of a millimetre of material, although in some places it can even reach half a millimetre. In general, we can say that on a tuned engine the ports resume their optimal size, while on standard engines the residuals of excess deposited chromium remain.