The Beta RR 4T Enduro information source

Intermediate Gear Upgrade

2005 Beta 525's are subject to a design flaw in the KTM RFS motor that causes the intermediate gear to fail. An extensive discussion of this issue can be found in the RFS Engine forum at Instructions on replacing the back torque limiting gear and the intermediate gear on the KTM motor can be found in this PDF. These instructions specify replacing the clutch cover with the '06 KTM cover, but this is not required - with a drill press and some patience, the Beta case cover can be machined to fit. Instructions for doing this and pictures of a broken Beta 525 intermediate gear can be found here.

Valve adjustments

Valve adjustments are to KTM spec, but are significantly easier on the Beta than on the equivalent KTM machinery. If you're not familiar with this process, see our step-by-step illustrated guide.

HT Oil Cooler installation

Installing an HT Racing oil cooler on your Beta is highly recommended for extensive street use, slow and tight trails, or high-altitude riding. Unfortunately, Dave forgot to take step-by-step pictures when installing it on his 525, but here's the finished product anyway.


Jetting on the Beta is very, very easy - buy the JD Jetting kit, be happy. If you'd like to see how to change the jets, look at the step-by-step guide to changing jets and needles on the Beta. Need a jet kit? Talk to JD. For high-altitude use, you may need to experiment with the proper needles; in Denver, Dave needed the blue needle and a 168 main on his 525 and it still felt a little bit lean.