That drum part is a tailored version of what's called "the Purdie Shuffle," without a doubt one of the most famous percussion riffs ever. Purdie used it to great effect on Steely Dan's 1977 album, Aja, on a track called "Home at Last." It didn't take long before Bonham was laying down his own version of it in the studio; "Fool in the Rain" was recorded late in 1978.
Purdie revived the sound on another Steely Dan song, "Babylon Sisters," used as the opening track on their 1980 album Gaucho. Toto drummer Jeff Porcaro used the Purdie Shuffle on the 1983 song "Rosanna." The fact that Bonham was so ahead of his time was not lost on musician and journalist Geoff Nicholls, who contributed technical analysis about the Led Zeppelin drummer in Chris Welch's 2001 book, "John Bonham: A Thunder of Drums." Nicholls writes:
Bonham was obviously hip to the rhythm years before most drummers had mastered it. ... All this is evidence that Bonham was keeping his ears open and developing his technique all the time. It provides a taster of his capabilities, and an indication of what he might have gone on to do.
touring the Brazilian samba schools with Jimmy Page. Nicholls says:
As with so many Zeppelin arrangements there is an unexpected twist [in "Fool in the Rain"] when, half-way through, the band double the tempo and roar into a sort of street samba. Bonzo's approach is inevitably a little heavy-handed by purist standards, but he's evidently aware of the caixa (snare drum) rhythms of Brazilian samba schools. The groove in a mishmash of Brazilian and Cuban/Latin feels, and Bonham climaxes the section with a manic timbale-like triplet snare drum roll which lands right on beat one of the returning original groove [the Purdie Shuffle].Purdie's also no stranger to the samba rhythm. He would tell you the difference between a samba and a bossa nova, but he's probably too busy just smiling and laughing as he soaks it all in. Watch some of these videos, and you'll see what I mean.
If Page is wise, he might make it to the Iridium jazz club, formerly the home of Les Paul, to watch as Purdie shows everyone what's up. He'll be appearing for three shows on July 16, 17 and 18, with the Doug Wamble Trio, featuring 37-year-old jazz sensation Doug Wamble, who from what I hear really knows his way around a guitar with a slide.
Incidentally, ask Purdie who all he's played for, and it's like listening to him recite an encyclopedia of funk, soul and jazz musicians. He seems to have no problem being known as "the world's most recorded drummer"; the moniker's emblazoned prominently on Purdie's official website. He may be even more influential than he is recorded, but don't tell him that and let his head get too big.