The Grumph

A Wisconsin builder combines a Greeves frame with a Triumph T100S engine to create a road-legal street tracker.

| March/April 2017

1962 Greeves/Triumph “Grumph” Special
Triumph 500cc OHV parallel twin, 69mm x 65.5mm bore and stroke; 9:1 compression ratio, 41hp at 7,200rpm
Top speed:
Two Amal 626 Concentric
4-speed, chain final drive
12v, Pazon electronic ignition
Greeves 24SC Hawkstone single H-section cast aluminum downtube w/special lower engine mounting plates/52in (1,321mm)
Greeves 24MCS motocross leading-link fork front, dual Koni shock rear
5in drum front and rear
3.5 x 18in front, 4 x 18in rear
Weight (dry):
290lb (638kg)
Seat height:
30in (762mm)
Fuel capacity/MPG:
2.5 gal (9.5ltr)

Marrying a Greeves frame with a Triumph engine makes for an interesting motorcycle with an interesting name: Grumph. According to the Merriam-Webster dictionary, grumph is actually a word, defined as “to grunt” — and that turn of phrase is entirely applicable to the machine in this article.

Not in a hurry to get to the altar, it was a nearly three-decade long engagement before builder Greg Lawless of Wisconsin got this particular Greeves/Triumph combination together. In 1981, a co-worker offered Greg a tired old desert racer. The machine was a 1962 Greeves Hawkstone 24SC powered by a 2-stroke, 250cc Villiers 34A engine. Although mostly complete, all was not well, as the transmission was locked in gear. “He was cleaning out his garage,” Greg recalls. “He didn’t want any money for it, but I turned it down as I had no pickup or trailer to take it away. He countered with free delivery, and the deal was done.”

For 10 years the Greeves languished as Greg focused on family and other projects. But in 1991, he and a friend visited the Isle of Man TT races. In a parking lot he saw his first road-legal Grumph, a Greeves Scottish with a Triumph 3TA engine. “Gobsmacked,” is how Greg says he reacted to the combination, and he knew what he wanted to do.

“I had to figure out how to put a Triumph motor in the Greeves frame, and I thought at first it would be an enduro-style special,” Greg explains. After some initial research, Greg learned he could fit a 500cc unit-construction Triumph engine in the frame, but prior to the days of the Internet, he had difficulty locating a donor engine.

Time passed slowly until 2008, when he connected with an eBay seller who had a 1970 Triumph T100S bottom end mixed with a variety of other Triumph engine parts. It was a Frankenstein engine, but it suited Greg’s purposes and he bought it. Build direction changed, though, when Greg saw a Greeves that had been set up for short-track racing — he quickly decided his Grumph would be a road-legal street tracker.

Jack Turner
11/30/2017 12:57:44 PM

I have the desire to build a Grumph for myself. I have an MX 6B rolling chassis and a '73 T100R engine. I'd like to contact someone who could guide me in obtaining the appropriate engine mounts, either drawings or the mounts themselves, and info on the pitfalls or things to avoid in the build. My e-mail address is and I am located in Missouri, USA. My name is Jack Turner. Thanks !

Ride 'Em, Don't Hide 'Em Getaway

Classic Motorcycle Touring and Events.

The latest classic motorcycle events and tours.