If the powerful pull of the bull market tempts you to stake all your mutual-fund money on the hottest stock funds, resist!

Yes, funds loaded with computer and telecommunications stocks have been soaring, while many conservative stock and bond funds have gone nowhere at all. But whatever the prospective reward of putting all your eggs in that one crowded basket, it isn’t worth the risk.

Don’t take my word for this. Look at what some of the big stars of the bull market are doing.

The managers of the Janus funds, for instance. This hottest of all fund groups, which has wowed investors with its bull-riding prowess in growth stocks these past several years, is bringing out a “value” fund at the end of February.

The Janus Strategic Value Fund will seek out “strong companies that may be undervalued or temporarily out of favor,” the firm’s chairman, Tom Bailey, said in a letter to investors in other Janus funds.

The Securities and Exchange Commission also comes down squarely on the side of diversification, having just issued a detailed statement imploring investors not to bet the ranch on top-performing funds. “Investors who buy hot funds risk getting burned,” said John Gannon, acting head of the regulatory agency’s education office.

Look beyond recent performance numbers, he said, and consider how long a fund has been in business, the risks it takes, and how it fits with your other investments.