On Track Again - Racing

Kenny Roberts is reunited with his championship-winning Yamaha YZR500 at Mazda Raceway Laguna Seca.

On Track Again - Racing

On Track Again - Racing

In grand style, Kenny Roberts kicked off Yamaha’s 50th anniversary in racing this past July at Mazda Raceway Laguna Seca. The two-time AMA and three-time world champion lapped the 2.238-mile circuit on three different Yamahas: a modified YZF-R1 streetbike; a YZR-M1 factory racer complete with custom “KR” numberplate graphics; and, minutes before Sunday’s MotoGP race, his 1980 500cc title-winningYZR500—the box-section aluminum-framed “0W48” that he raced in five of eight events that season.

Both Roberts and his YZR500 were well-prepared for the occasion. While Roberts was lapping Mallory Park in England earlier in the month as part of The Vintage Motor Cycle Club’s “Festival of 1000 Bikes,” ex-racer and enthusiast Dante D’Ambruoso and longtime Roberts family friend Joe Fenech were prepping the diminutive two-stroke at D’Ambruoso’s shop in San Jose, California.

“I got my hands on the motorcycle three months ago,” D’Ambruoso told me. “I was just going to clean it up, but I ended up going through the whole thing; it was 99 percent apart. The bike had a lot of issues because it had sat for 20-some-odd years.”

Work on the piston-port inline-Four included straightening the rearward-spinning twin crankshafts, first locating and then installing new pistons and cleaning the finicky Mikuni carburetors. “It’s really a miracle that the bike ran,” admitted D’Ambruoso. “Corrosion from the magnesium cases pretty much did in the engine.”

Speaking of magnesium, Marvic in Italy replicated the original 18-inch cast Morris wheels. “There’s no way Kenny could have ridden the bike with those old wheels,” said D’Ambruoso. “Marvic bent over backward for us.”

D’Ambruoso also delved into his personal stores. “We found out we needed brake pads,” said Fenech, “and damned if Dante didn’t have a set.”

Kenny Roberts kicked off Yamaha’s 50th anniversary in racing.

The King rides again: Kenny Roberts suited up several times this past July at Mazda Raceway Laguna Seca. He admitted that it was more track riding than he’d done in a long time. “If the fans liked it,” he said, “it’s fine.”

Prepping the bike was one thing; riding it at Laguna was another. “The bike didn’t like the weather on Thursday,” said Fenech. “The engine wouldn’t rev past six grand. Dynojet saved us; we had the bike on their dyno four times on Friday.

“We had just 30 minutes of track time for both the 0W48 and the M1. We had some good encouragement from Kel Carruthers and Sandy Rainey. Bud Aksland was there, too, cheering us on. They all threw in moral support. None of them wanted to work on the bike, though!”

D’Ambruoso admitted that Roberts’ high expectations for the bike and its performance wore on him. “When you’re in the midst of a storm, it’s hard to see the sunshine,” he said. “The words of encouragement I got from Sandy and Bud were huge to me.”

Roberts, along with track manager and friend, the late Lee Moselle, was instrumental in bringing Grand Prix racing to Laguna Seca, his home track. For the 1988 United States GP, four years after Roberts had officially retired, the track was modified and lengthened from 1.9 to 2.18 miles to meet then-current FIM standards. I was surprised to learn that he’d never ridden around the current circuit.

“I did all my laps on the old one,” said Roberts, who will be 60 years old in December, “so I’m still learning the track as I’m going around.”

I asked if the circuit was at least familiar to him. “Half of it, for sure,” he nodded. “Turn 5 on to the straightaway and over the hill. Over the hill’s not quite as scary as it used to be.

“Of course, the bike’s not running in top condition. We need two practice sessions, I think, to get the jetting where it would actually be, you know, zingy.”

On Sunday, amid great fanfare, with fellow world champions Carruthers, Wayne Rainey and oldest son Kenny Jr. looking on, Roberts made two flying laps. Was the bike the same as he remembered?

“No, it’s a lot different,” he replied. “And I’m still bitching about it! How it was rich and wouldn’t do a good wheelie. That kind of pissed me off. Other than that, it brought back a lot of memories—watching the people waving like in the old days.”

Compared to the modern M1 that he’d ridden one day earlier—and, by his own admission, nearly tossed away—Roberts said the two-stroke was “mellow.”

“The brakes don’t work good enough to lock the front wheel, so I had no problem . I overshot Turn 1 once and I thought, ‘Don’t fall off here, you dipshit!’”

Does Roberts fancy another go? “I don’t think I’ll make the 100th anniversary,” he laughed. “So, they’re probably going to have to count me out on that. But who knows? I take things as they come.”

012 Roberts recounts his on-track experience at Laguna Seca with CW Managing Editor Matthew Miles

011 Roberts enjoys a laugh with fellow three-time 500cc World Champion Wayne Rainey

010 Number One

009 Kenny Roberts wheelies his title-winning 1980 Yamaha YZR500 out of Turn 11 at Laguna Seca

008 Kenny Roberts

007 Kel Carruthers discusses days past with CW Technical Editor Kevin Cameron

006 Square-tube alloy chassis

005 Pistons and cylinders

004 Nearly complete

003 Engine removed

002 Crankshaft assemblies

001 Beginning of teardown