OBDi - Polaris 120 Engine Parts

There will be more engine parts listed as I have time to add them. Thanks for your patience.
The GEN8 valve spring is the best valve spring available today and 100% ISR legal for both Ice Oval and SnoX racing.
The GEN8 valve spring is the best valve spring available today and 100% ISR legal for both Ice Oval and SnoX racing. These are engineered to barely lose any performance after the first couple heat cycles where they lose about .012" in free length. After that they hardly change at all and many customers use the same valve springs for half to a full season. With the use of rev limiters it's now even more important to have good valve springs so you can get out front quickly because once the rev limiters kick in everyone is running the same speed theoritically.

Adjustable Main Jets and Pilot Jets

The adjustable main jet replaces the bolt that holds the bowl onto the carburetor and allows you to adjust the fuel flow. By changing the fuel flow you can fine adjust the engines peak peroformance as tempature and oxygen levels change throughout the day of racing.
We offer two different adjustable main jets for the Polaris 120s, both non-cable and cabled versions.
NON-CABLED: The non-cabled version is simply just the adjustable main jet that installs into the bottom of the carburetor.
CABLED: The cabled version has a cable that connects to the jet and can be routed to the top of the engine compartment so it's easier to reach and adjust. However, the cables that's used has memory and doesn't always stay exactly where you set it so caution to watch for this is advised.
PILOT JETS: We offer several sizes of pilot jets sold individually, and now offer a pilot jet kit. The pilot jet kit comes with #55, #57.5, #60, #62.5 and #65 for just $30.

Click Picture to Enlarge

KOSO Rev Limiters (ISR LEGAL)

As of the 2014/15 season, rev-limiters are now required to be used on all stock 120 class races. These KOSO rev-limiters restrict the maximum RPM to 6850 and are the only ISR approved rev-limiter devices.
This rev-limiter uses a 9 volt battery for power so there is no power required from the snowmobile itself.
A very simple three wire hook up to install.
This rev-limiter is for the Polaris 120 and also fits the Arctic Cat and Yamaha with the Yamaha engine (2010 and newer).
TIP #1: Keep a fresh battery in the limiter. As the battery power lowers so does the maximum rpm the limiter will allow.
TIP #2: Do not buy from someone at the track. Most folks know that each rev limiter allows a different maximum rpm and you don't want to buy one that's been testing and found to have a lower rpm. When we receive these we immediately seal the bag for your security.
TIP #3: If you have a rev limiter and the switch fails, use an adjustable main jet to set 6850 max rpm. Do this buy adjusting rich and then lean the engine until the rpm reaches 6850 on your tach. It's not legal to keep it like this but it will get you through a weekend.

9v Battery Box for Rev Limiter

The battery box on the rev limiters are notorious for breaking or failing, so don't let yourself be caught ready to race and having to withdraw because you don't have a working rev limiter. These are cheap so be sure to have a couple in your toolbox for emergencies.

KOSO Mini 4 Tach

The Mini4 tachometer uses an LCD screen powered by an inner CR 2032 changeable battery that allows installation on any vehicle. With the small, compact and user‑friendly size, it is perfect for many applications. It also features a backlight, has a RPM display warning and also keeps track of your max RPM.

*** NEW 2022 ***
KOSO's mini RPM tach is a surface mountable Tachometer that is accurate to 20,000 rpms and features a resetable maximum RPM recall. This multifunction meter is programable to nine different firing patterns to accomodate two and four-stroke engines.
This tach is PERFECT for racing as it only has a 0.5 second delay between reading and display. Most mini tachs have up to five second delay.
This tach retails for $89.95, but is currently being offered by Olson brothers at a discount.
Measures 33.7mm (1.33 in.) H x 61.5mm (2.42 in.) W x 15.6mm (.61 in.) D

Click Picture to Enlarge

Spark Plugs

Standard and Iridium NGK spark plugs for Kitty Cat and all 120cc sleds. Order on-line or call 651-485-3771.
Iridium plugs last longer and have more spark surface for better fuel ignition.
E3 plugs are designed for high performance engines and have a diamond shaped electrode for greater spark.

Click Picture to Enlarge

Send mail to the WEBMASTER with questions or comments about this web site. Copyright © 2004-2011 Olson Brothers Dist, Inc.

Send mail to the WEBMASTER with questions or comments about this web site.
Copyright © 2004-2011 Olson Brothers Dist, Inc.