China Yuchai International Limited (NYSE: CYD) saw its shares decline 6.2% on Wednesday after short-selling firm J Capital Research published a report expressing doubts about the sustainability of the engine maker’s recent growth.
J Capital noted the stock has more than tripled over the past year even as the company trades at roughly 7.5x EV/EBITDA, a multiple the firm described as modest relative to Yuchai’s reported performance. The short seller highlighted that Yuchai’s earnings reportedly rose 66% in 2025, and revenue increased by about 30% the same year.
Those revenue gains stand in contrast to the broader Chinese truck market, which J Capital said expanded by no more than 1.5% in 2025 when excluding new energy vehicles. The research note compared Yuchai’s results with those of larger rival Weichai Power, which J Capital reported achieved total sales growth of 7.5% in 2025 while seeing its profit decline.
Despite the strong top- and bottom-line moves reported by Yuchai, J Capital raised questions about whether the company can maintain that momentum. The firm pointed to two structural pressures it believes could constrain future demand: a prolonged downturn in Chinese real estate and construction activity, and an industry-wide transition toward electric vehicles. Both factors, J Capital suggested, could weigh on traditional diesel engine demand over time.
Beyond market dynamics, J Capital called attention to certain characteristics in Yuchai’s financial statements that it said could imply sales are being recorded that may not ultimately be paid for without the use of special bank financing arrangements. The research firm did not supply additional public evidence beyond those statements in its report, but it used those observations to question the durability of the company’s reported sales and profits.
Yuchai has promoted growth in high-powered engines used for data center cooling, a segment the company has emphasized as a newer growth avenue. J Capital observed, however, that only a small portion of those engines are manufactured by Yuchai itself, with the remainder procured from external suppliers and resold. The short seller said the recent jump in revenue and profit came mainly from Yuchai’s traditional truck and bus engine business rather than this nascent segment.
J Capital also raised corporate governance concerns. The firm noted that in October 2025 the president and corporate chief accountant of Guangxi Yuchai Machinery were detained by Chinese authorities, and that the former chairman of Guangxi Yuchai was detained in July 2025 on suspicion of legal violations. J Capital presented those detentions as additional context for investors assessing risk.
Market reaction and outlook
The immediate market response was a share-price decline of 6.2% following the publication of the J Capital note. The report lays out a mix of market, accounting and governance questions that investors may weigh as they consider Yuchai’s valuation and recent operating performance. Absent further public disclosures or clarifications from Yuchai, the issues raised by J Capital remain points for investor scrutiny rather than definitive conclusions.