ATV Clutch Technology

**JThompson** · 09-16-2006 01:19 AM

ATV Clutch Technology

Several different things can cause your clutches to over heat and cause poor performance and/or part failure. These problems can show up on any brand with automatic belt driven transmissions. The three most common causes are belt slippage, plugged vent lines, and homemade snorkel kits.
When the clutches slip the belt, this will cause extra heat in the belt and clutches and a loss in performance. Belt slippage can happen when the clutches are over worked. Pulling heavy loads, larger tires, using high range in extreme conditions, improper clutch set up and incorrect belt deflection can cause belt slippage. Clutch kits are available through EPI to help fix some these problems. Other problems be can fixed by changing riding styles, using low range in extreme conditions, and proper maintenance.
Another over looked cause of clutch heat is plugged vent lines. Grass, dirt, mud, and mice can get into some of the vent lines for your clutch housings. This causes heat to build up and does not let the cool air in. Mice can build nests that block the vent line when machines are stored for any amount of time. The clutch system will then run hot and eventually over heat. Whenever any clutch work is being done be sure to check for any vent line blockage or if you notice extra clutch heat.
Home made snorkel kits or breather kits for clutch housings may keep the water out but also keep the heat in. When using a snorkel kit it is imperative that you maintain adequate ventilation for your clutches. Reduction of diameter, lengthening, incorporating multiple bends, or modifying the vent tube will result in increased heat build up in the clutch housing and damage may occur.
How Over-Sized Tires Affect Clutching
Oversized tires have a lot of benefits, such as better traction and performance and greater ground clearance. The down fall to these tires is loss in power, throttle response, and increased belt slippage.
Usually, oversized tires weigh more than the stock tires the machine is set up for. It will take more power to turn the extra weight. This is where it helps to use lighter weight rims.
Most oversized tires will offer more aggressive tread, which will make it harder for the motor to turn the tires. Even if the tires and rims are lighter than your stock tires, they will still start out in a higher gear ratio due to the taller tire. With the extra weight, traction, and height there is an increased strain on the clutch system causing belt slippage.
The good news is your clutches can be adjusted to help compensate for oversized tires. An EPI Big Foot Clutch Kit is specially designed for machines with larger, more aggressive tires. This kit will grip your belt better, give you better backshift and throttle response, and more low-end and midrange power. These kits work great and allow you to get the most out of your machine.

**tigmaster** · 10-14-2006 12:31 PM

I don't mean to be rude, but if you have a belt transfering power on your quad or bike then I dont think you should be riding it. Whoever understands belts and the power loss through belts, should know that having a belt on anything should be tried to be avoided. For example, polaris, the American crap brand. They roll with a CVT, which uses a belt which is smashed between to pieces of metal, acting as a clutch. I won't even get into some of polaris' "design inovations". polaris does have problems with the design though, many people I know have blown belts, but it could just be the polaris factor.

**JimmyHoffa** · 01-27-2007 07:00 PM

They sell these clutches in some bikes where there are all these plates on top of eachother, and when you let out the clutch, they all get smashed together and your bike goes really really fast all at once. I've never seen rubber drip out of the bottom af any of them. :-)