Hardtail Hodaka 125 Powered GRM Trials Bike

[JAQ]

I am a trials rider from North Carolina. The bike belong to a friend of mine. The owner of the bike still rides trials at the age of 74 like someone half his age.
The bike in the photos is an iron cylinder 125 Hodaka powered GRM ( Grapevine Racing Motors) Hard tail trials bike. This bike was built around 1998 as a replica to the original hardtail built by Bill Grapevine in 1964. It weighs roughly 160 lbs. The foot pegs are set low and behind the leading edge of the rear tire. The lack of seat is perfect for trials riding as it allows you to more around on the bike more and let the bike come up under you during a large step/obstacle. You would be surprised what this bike will do.

The engine is a piston port motor with a mikuni VM-18 carburetor. A custom brass flywheel weight was built by Bob Ginder from B&J racing. The exhaust is made out of pieces of copper tubing ...

Working on creating a trials exhaust system for this bike. I know this can help to have a long header pipe, packed expansion chamber and stinger. Has anyone ported these engines for trials work? Or built aluminum reed valve cylinder trials motor? I appreciate it.

Thought it would interest you. Enjoy the pictures!

Thank you -JQ

[hodakamax]

Fun pictures of the trials bike in its native habitat!

Max

[RichardMott]

Stan Bollinger from Maryland rode a Hodaka powered GRM for many years. I don't think he rides anymore. He was injured in a bicycle accident about 5 years ago. in the photo he is the one second from the left standing next to the handsome guy in the orange Hodaka Tee shirt.

Hodaka riders 2007

[racerclam]

I have done several porting on iron barrel wombat trials engines , to name a few , Bill Cook , Jay Layel, Leo Stinnet , Robert Lord . All very successful in competition. For piston port applications I add a victory port just as in the combat wombat, this really makes a big difference .

Rich