4597 Calle Del Media

Ft. Mohave, AZ 86426

+1 (928) 763-7600


About Group K

Group K is a professional aftermarket high performance shop in Fort Mohave Arizona (about 50 miles north of Lake Havasu) that specializes in engine modification kits for Yamaha, Sea Doo, Kawasaki, Polaris, and Tigershark personal watercraft. We have been building race and recreational watercraft since 1986. Prior to that, our technicians had 15 years of high performance two-stroke engine modification experience with national level road racing and motocross motorcycles, as well as racing ATV’s and Super Lite’s (also known as Honda Odyssey’s).

What We Do – The engine kit work by Group K consists primarily of modification to existing pieces. We also build complete race machines. Unlike other aftermarket companies, we do not manufacture or distribute any aftermarket bolt-on parts. This gives us the freedom to test all available pieces, and recommend the bolt on parts that offer the best performance and value…regardless of manufacturer. Since all of our tests are conducted ONLY on machines equipped with our modifications, we cannot confirm which parts will work best on stock machines (or machines modified by other shops). Nonetheless, it has been our general experience that what works best with our engine kits…works best on most setups.

Furthermore we do not sponsor any racers or race teams. We find it to be a conflict of interest to hire a professional rider to go out to beat our customers. As an added conflict, paying customers will never believe that they are buying exactly the same equipment as the sponsored rider has. We have pro racers that do most of our high speed test riding. However, to us, they’re just test riders and nothing more.

The Purpose of Our Files – The primary theme of virtually all of our files is the technology, and what it’s worth in dollars. At Group K we believe that every kind of technology has to justify its price tag with a real world value. Because we have such an impartial attitude about various aftermarket parts, we get many telephone calls from PWC owners seeking general information about what modifications and parts (for the money spent) will work best on their machine. Unfortunately, our high paced work load permits our technicians only a limited amount of time for phone conversations. Rather than engage in lengthy phone calls, we usually offer to mail our detailed and “model specific” technical pamphlets to the caller.

The purpose of our Internet site is to offer inquisitive owners the full measure of information they want, without a lengthy telephone call. This reduces the customer’s phone bill, and saves our technician’s valuable time. We prefer that phone calls with our customers be focused on suiting their particular performance needs…not on lengthy technical dissertations.

About The Files – Our technical files are broken down into sections here, in the menu on the left border.

The specific make/model sections contain the product literature sheets that we mail out to customers. They are all different and exclusive to the particular machines listed.

The “General Technical” link contains a collection of technical articles, many of which have been published in various PWC magazines.

In the archived documents section you will find information on older models and some of our early articles. Particularly unique are the “Between The Lines” documents which are comments on most current magazine technical articles. Be sure to read the introduction first.

We are planning another section called the “Latest Updates” which will contain links to files that will be updated approximately every 30 days. These files will contain the latest information on current technical issues. Please keep checking back for this new section!

About our Content – This site is not a forum or a soap box for various causes. The information in these files is the result of our current hands-on experiences and on going field tests. It’s likely that some individuals may question some of our content…that’s to be expected. However, the results of our field testing experiences are much harder to question. It is also our intention to avoid political issues except where they directly effect relevant technical issues. There are already enough folks involved in the political mud slinging business.

We ask that you forgive the occasional “typos” that have escaped our spell-checker and proof reads. We hope that the quality of our text will compensate for our lack of editorial perfection.

About Responding – We certainly appreciate your comments and input with regards to the technical information in all our files. Unfortunately, time does not permit us to respond to all email inquiries. However, our email address is groupklemm@aol.com

We will periodically try to respond to as many as possible, whether by direct response or an added entry to this web site. For customers who have additional questions about the Group K modifications or engine kits outlined in this web site, please feel free to contact one of our technicians by phone at (928) 763-7600. Happy Reading!