I was riding my 05 SP700EFI for a couple days on a trip. The first day, on downhills, felt the EBS kick in and really liked it (never had EBS on my old 400). The rest of the trip, every downhill, I had to ride the brakes, no EBS. Not sure how the system works, but sounds odd. It is still under warranty, so will probably take it back to the dealer, but I was hoping to get some input first. Has anyone else had their EBS stop working?

Thanks!

 

Well you said down hill and the polaris set up is just ebs on the rear wheels so your probablly feeling the rear wheels break free and slide

 

Thanks Polaris. Maybe I didn't explain right. I know that I only have rear EBS, but now the EBS doesn't engage at all. What I was wondering is how does the EBS engage? Just thought I might be able to look things over before having to take to the dealer which is about 50 minutes away.

 

The EBS on a polaris is like a one way roller clutch inside the primary. The belt will ride on the primary when decelerating, but instead of the secondary overrunning the primary creating freewheeling the one way clutch will keep the belt engaged to the engine, which in turn gives a ratio between the engine and rear wheels to create engine braking.

 

The primary clutch has a ribbed centre hub, the inside of the belt has matching ribs. When you decelerate the clutches will give you engine breaking until the engine rpm drop close to idle. At this point the sheaves separate and the belt drops on to the ribbed hub (EBS clutch aka sprag clutch aka one way clutch) causing friction between them. The secondary clutch is now driving the engine via the EBS clutch.
Your problem: no EBS
I have the same problem with my 01 Sp and I am quite sure it is due to worn shims on each end of the EBS clutch. To inspect the EBS remove the clutch cover and the belt. Grab the EBS clutch and slide it in and out, there should be very little end float.
Another test: before removing the belt check the drive belt free play, it should be approx. 1.25". What I found was there was no slack in the belt because the belt wouldn't drop over the EBS clutch ribs thus no EBS.
Maybe this weekend I'll take it apart and replace the shims (again).
I hope this makes sense to you.

 

Thanks for the explanation, makes sense now. I only have about 200 miles on it but I'll take a look (after I get the bent front shaft off my SP400). Will probably still take it to the dealer since it's still under warranty.