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International Twinshock Association
Trials By Trials Riders For Trials Riders


Hunter...First Trials!


Caulkboy Stylin


Caulkboy section 1



 Baker Award Winner2008

Hold on George!


Honda-Honda 2 Ready for action!


End of an era....We don't think So!


Greeves, Cotton, James.....History lives Here!


Tiger Cubs...Still a favorite!


Latest Majesty


The Guru's Famous James


The Trialsrooster on a Chicken


Hockeyboy and the log! 


2015 ITSA National Champ Series Results



2019 ITSA National Championship Series Schedule!


Round 1 - B&J's Ranch, Dickson, TN., November 4th, (2018)

Rounds 2 & 3 -  Charlie Nash's Ranch April 27th and 28th
Rounds 4 & 5 - Charlie Nash's Ranch May 18th and 19th

Round 6 &7- Chip Hart's Ranch June 22nd and 23rd

Rounds 8 & 9- Chad Praters Ranch July 27th and 28th (NEW LOCATION!!)

Round 10 & 11- B&J's Ranch September 7th and 8th
Round 11 &12 -  Trials Training Center September 21st and 22nd

Round 13 & 14 - Stu Davis's Ranch October 26th and 27th (NEW LOCATION!!)

Rounds 15 - 
B&J Ranch November 9th (Year End Banquet!!)

Round 1 2020 - 
B&J Ranch November 10th






HomeITSA History

What exactly is ITSA? Well, ITSA (International Twin Shock Assoc) was formed, and is continuing to develop, as an association for trials enthusiasts by trials enthusiasts.


The camaraderie shared in building, restoring, riding, and competing with other like-minded individuals is paralleled in satisfaction by very few activities. Whether one chooses to restore a bike and ride it within its original time period or use their creativity to design and build a special, staying within the confines of air-cooled, drum brake, twin shock, ITSA provides a place for you!


Limiting the technology we can use will somewhat restrict the motorcycle’s capabilities. In doing this, the severity of the terrain the bikes can safely negotiate becomes more reasonable. This, in turn, opens the door for more riders to safely compete, making for a more interesting championship.


So, to sum up what we are about…We are trials enthusiasts, new and veterans, who are creative in our machine design and look forward to getting together with those who share these interests to compare ideas and put them to the test by competing.


Above all else, keep the fun in observed trials!!


Now, for a history lesson....


When you're talking about twin-shock trials competitions in the U.S., there is a window where motorcycles from about 1979 to 1985 are missing. The advent of modern mono-shock trials bikes signaled the end of the twin-shock era. That six-year period created a void of missing twin-shockers, in most rules interpretations, that included all the SWM's, Italjets, the Fantics, some Montesa's, the last few models of Bultaco's, and the Honda Reflex TLR200 and TLR250, to name a few.


The difference between the capabilities of the twin-shock bikes and the mono-shock bikes are obvious. The latest technology employed on today's modern mono-shock motorcycles make them able to tackle huge obstacles. The skill and nerve required to achieve success in executing these feats is beyond what most are willing to try, and the ability to go to work on Monday mornings has become one of those things that is necessary in our lives.

This limits the number of participants capable of attaining top expert rider status. Most twin-shock motorcycles and the abilities of their riders and the sections that they compete in are more closely matched to the average rider's capabilities. This makes an ITSA Trials competition much less dangerous to man or machine, while still being quite challenging, and much more fun.


Another thing that modern mono-shock trials competition does not afford is the creative aspect of rules interpretation, bike building, and the modifications that vintage trials bikes afford the rider. The modern trials mono-shock motorcycle, as it comes out of the crate, is ready to ride and there are no modifications required. For those of us who have experienced the walk through time and the evolution of most things mechanical, somehow feel that something is missing if you don’t have to take your bike apart and work hard at modifying it or designing parts to make it work better, striving to out-engineer your fellow competitor, as well as to out-ride him.

The main class of ITSA is the Modern Twin-Shock category. The rules are basically this:


Ø Air-cooled engine


Ø Drum brakes


Ø Twin shocks


Pretty simple, huh? What’s known in most racing circles as “run what you brung”. That’s what ITSA is all about: build the bike, ride the bike. The limiting factor of air-cooled engines, drum brakes, and twin-shocks will keep the obstacles reasonably sized which will allow more riders to reach the top ranks, providing a more tightly-contested championship series.


The format that ITSA is striving to use is a throwback to the history of Trials itself from England and Scotland. One-line sections with no split markers, with section difficulty tailored as much to the capabilities of the machines of the era as to the abilities and talents of the riders.


Come join the fun!