Member Rich Wride owns an 850 Norton Commando but also owns this non British machine. I am sure all of you will find the story of this restoration very interesting. Here is his letter:
I appreciate the interest in the GRM and would be happy to provide information for the website.
The bike is a 1973 GRM Trialsmaster. Designed by American trials pioneer Bill Grapevine. Bill was an early trials enthusiast involved with the introduction of trials in the USA in the 1960's. GRM stands for Grapevine Racing Motors.
Mr. Grapevine contracted with the Moto-Islo motorcycle company in Mexico to build 1575 bikes from 1971-1975.
It is a 215cc two stroke motor. Four speed.
I found the bike last September rusting away in my friend John Kinney's basement. I was immediately mesmerized by it. 10 years earlier John had rescued it from the garbage truck after someone had sent it to the curb. John said I could have the bike on one stipulation, I had to get the bike running again and could not abandon it. John also offered to provide his mechanical expertise and work with me on the project.
The project was a considerable challenge because this was my first novice "restoration". This was further complicated by the fact that Moto-Islo went out of business in 1980 and parts were unobtainable.
The small number of bikes produced made the prospects for used parts slim. The missing piston almost made the project impossible. I could not find anyone for months that had ever heard of a GRM.
My lucky break came after I found Bill [Grapevine] living in Kansas and he was happy to advise and encourage me.
Blind enthusiasm for the bike prevailed. One year wiser and alot of dollars poorer I finally completed it!!
The biggest challenge was finding a piston. After a hundred or so phone calls all over the USA, South America, and Mexico I determined only 3 new pistons remained and the owners were not selling them!!
The original manufacturer, a German company, MAHLE was not interested in re-making the piston either.
One of the piston owners graciously supplied one to be copied. Bud Clark of J&B Imports worked together with Venolia in California to make the piston.
I powdercoated the frame, polished, painted and refinished or rebuilt almost everything on the bike.
Now I'm looking for the next project- Maybe the Commando??