I was recently asked for advice on the purchase of an EFI OSSA. After a bit of correspondence, it occurred to me that others may have the same questions.
Firstly, understand that I consider the OSSA as much a work of art as it is a trials bike. The header for this page is my 1993 Yamaha TZ250. It's a grand prix roadracer that is unlikely to ever be ridden in competition again. But to me, it's also engineering art and I display it proudly in the entryway to my home. When the OSSA is no longer useful to me, it will meet the same fate.
The following is written in boldface type on my homepage because it is so important: If you ride trials, like to fix things, and are among the top 5% of fixers, the EFI OSSA seems like a natural choice. Let this help guide your decision.
Owning a single OSSA is risky. Many OSSA owners have 3 or 4 of them. Later bikes are more desirable than earlier ones. By the 2014 models, OSSA had learned a lot and most of the serious flaws had been eliminated.
Parts availability is the biggest unknown going forward. Although fairly modern, the OSSA is more like a vintage/classic trials bike and requires a committed owner.
There's nowhere to take the bike for service - you will be on your own. Having access to machine shop equipment may be necessary to make or repair unavailable parts. A general knowledge of electronics will be very valuable as well.
The OSSA is almost the exact opposite of my Montesa 4RT. That bike worked very well for me right out of the crate. I'd probably still own one if it weighed the same as the OSSA - but it does not.
Before making a decision, I suggest that you read every page of this website. If that does not scare you away, I then recommend building the DIY diagnostic interface to communicate with the ECU of any OSSA you are considering acquiring. By doing that, you can discover how much operating time the ECU has accumulated. You can also see if any historical error codes have been recorded.
Some secondhand bikes still look almost new because they were difficult to start or never worked properly from the beginning.
Once running properly, and barring crash damage, the OSSA should not need much attention for the first, say, 200 hours. I have a bike with over 500 hours on it that still works well. The reliable Japanese electrical system is a huge advantage of the OSSA and one of the things that first attracted me to it.
I believe the value of these bikes will appreciate as time goes by, and I hope this website will contribute to that appreciation.