Probably the most widely copied motorcycle on a worldwide basis, the 5th-generation of the Honda CG 125 released in late-'99 was the last one to be fitted with a pushrod engine in Brazil until being phased out locally in 2009, in a time when some small competitors brought Chinese copies for CKD assembly while Honda switched to the same OHC layout carried over from the international Honda CB 125 at the time, yet the name CG is so strong in Brazil it was retained despite still being mostly used elsewhere on motorcycles fitted with OHV/pushrod valvetrain. Sure Brazil following stricter emission standards than places such as Pakistan where the pushrod engine is still available in Euro-2 trim with carburettor, or even the United States where a less stringent regulation applied to motorcycles enabled the grey import of small-displacement motorcycles from Mexico in a seemingly legal way covered by the NAFTA free trade agreement, would seem to prevent the pushrod engine to remain available in the CG, but in fact it seems like emission regulations were not a justifiable reason for the Brazilian phaseout of the pushrod engine. Just like many other engine manufacturers keep up with modern features such as electronic fuel injection which has been effectively widespread on motorcycles in the Brazilian market since 2009, and it still could be fitted by Honda itself to the pushrod engine like it's nowadays also fitted in China to the pushrod engine by its official joint-ventures for the domestic market as the emission laws there became tighter there, yet remaining less stringent in many export markets where a carburettor is still prefered, an actual demand for such a simple valvetrain design is still the driving force (no pun intended) for the Honda CG 125 having become the most copied motorcycle ever.
While small enterprises which resorted to outsourcing for local CKD assembly of Chinese copies of the pushrod Honda CG 125 eventually went away for the most diverse reasons, including lack of emissions compliance as many retained a carburettor until it was no longer viable to retain resonable performance levels, it's still fairly common to spot the original model in Brazilian streets being used for actual work, to which the reliability of the pushrod engine under the harshest conditions is a valuable asset, because the lack of a timing chain leads most riders to regard this engine as a less maintenance-intensive option to newer OHC models which have a timing chain and its tensioners to require inspection and sometimes a replacement. Of course EFI would be a desirable feature had the pushrod engine remained available in Brazil, mostly because of eventual improvements to the fuel savings it could result, and other measures such as the oil-squirt for piston cooling added for the 2004 model-year of the Honda CG 125 in Brazil enabled the engine to run leaner instead of relying on a richer air/fuel ratio simply as a cooling aid at the expenses of the higher hydrocarbons (HC) emissions which are basically unburnt fuel being wasted through the exhaust. Considering how the old pushrod Honda CG 125 and its international derivatives are still directed toward a more conservative buying pattern wherever they remain available, and also the pushrod 125 was retained from 2004 when the OHC CG 150 was released in Brazil to 2009 when EFI became standard for the 150 and a carburettor-fed 125 OHC version always fitted only with a kick starter meant to replace the pushrod 125 was also introduced, and the OHC 125 would only receive EFI from 2016 to 2019 when it was phased out in Brazil with the local models of the CG retaining only the 160 engine introduced in 2016, it can be argued the economics of scale dictated the phaseout of the pushrod engine more than emission regulations.
Sure keeping a separate engine exclusively for entry-level utilitarian motorcycles, to which the price is a more critical aspect than for a leisure-oriented model usually with a more sophisticated engine, can be harder to justify once it's remembered Honda haven't gone as far as some Chinese factories which have made larger-displacement versions ranging from 150 to 200cc, and sometimes they go as far as 250cc with liquid cooling in order to be used in cargo tricycles and other special vehicles. Definitely resorting to different displacement ranges with the same basic project, while retaining the dependability of the pushrod engine for harsher conditions to which a chain-driven OHC valvetrain would be less desirable, could still give Honda an advantage to retain so many conservative riders who are still out there, yet left behind from the new motorcycles market in Brazil. While a pushrod layout would still enable the usage of a timing chain in larger engines such as a Harley-Davidson Milwaukee Eight fitted to the current generation of the Big Twins or the Ford Godzilla fitted to full-size trucks, the simpler gear-driven layout of the valvetrain in the Honda CG 125 engine was also important to consolidate the preference in Brazil for 4-stroke engines and put an end to the former dominance of Vespa and Lambretta in the market for small-displacement motorcycles, and to a minor extent in other countries where 2-stroke motorcycles were only phased out due to carburettors remaining common, so maybe it was a mistake for Honda to simply phase the pushrod CG 125 engine in Brazil while there was still some room for improvements.
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