94 Sportsman 400 Clutch Kit - Polaris ATV Forum
ATV Performance Modifications Have Modifications? Want to ask about a mod? Having problems with a certain mod? Ask and post here! Carbs, Exhausts, Engines, Etc...

LinkBack Thread Tools Display Modes
post #1 of 3 (permalink) Old 12-11-2016, 03:03 PM Thread Starter
ATV Enthusiast
Sti1471's Avatar
Join Date: Nov 2016
Location: Utah
Posts: 32
94 Sportsman 400 Clutch Kit

I have a 1994 sportsman 400 2-stroke. I am looking to get a bit more power out of it and I have read that some people have installed clutch kits on their Sportsmans with some great results.

The riding I usually do is trail riding in the rocky mountains in Utah. So trails can be a basic dirt road, and 100 yards later, a steep rocky road. So I am looking to increase the lower end power, without giving up too much top end speed.

I cannot seem to find any tech articles about what weight of clutch kit spring(s) to use, whether to change the weights, and or what combo of spring / weight would give me a good power boost.

Any information would be very appreciated.
Sti1471 is offline  
Sponsored Links
post #2 of 3 (permalink) Old 12-12-2016, 01:35 PM
ATV Enthusiast
thepepper's Avatar
Join Date: Jun 2016
Location: Ottawa
Posts: 41
If you google polaris 400 2 stroke performance parts you'll get lots of sites that offer tons of stuff. There are some big bore kits that pump out a crazy amount of power out of these engines.
thepepper is offline  
post #3 of 3 (permalink) Old 12-12-2016, 01:45 PM
ATV Enthusiast
thepepper's Avatar
Join Date: Jun 2016
Location: Ottawa
Posts: 41
Some additional information on the 400 before you go throwing good money after bad. Have you checked the compression? The stock piston is a weak point and they break over time. If you're not up around 120-140 psi, ebay has over bore wisco piston kits that make an old engine come alive. Another sore point is the common shaft for counter balancer and water pump. If your counter balancer oil is milky, it means the coolant has leaked past both the water pump seal and the counter balancer oil seal. This can be a significant problem as the shaft gets pitted and makes a new seal near impossible. I had to send mine out to have a new stainless steel sleeve pressed on. Based on the age of yours, If the rest of the machine is in good shape and you're mechanically inclined with some tools, get on Amazon and order an All Balls rebuild kit which includes all bearings and seals for the crank and water pump. Tear it apart and rebuild. I did my complete engine and it keeps up with my 04 700 no problem now.
thepepper is offline  

  Lower Navigation
Go Back   Polaris ATV Forum > Polaris ATV Technical Discussions > ATV Performance Modifications

Quick Reply

Register Now

In order to be able to post messages on the Polaris ATV Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
ASM-CLUSTER,110MM,W/FUEL (Speedo Cluster) FOR SALE KLCFLC Polaris Sportsman 1 11-21-2016 02:09 AM
3280431 ASM-CLUSTER,110MM,W/FUEL (Speedo Cluster) KLCFLC ATV New Members 0 11-19-2016 03:12 AM
2002 sportsman 500 bearing carrier fishnfool ATV Brakes & Suspension 2 07-13-2016 09:50 AM
Softer rear shocks/springs? Unitoo1 Polaris Sportsman 10 04-25-2016 04:20 AM
1994 Polaris 400L clutch cover alternatives? bigcheese ATV Repair and Maintenance 2 03-09-2016 12:19 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome