Ski-Doo pDrive clutch ramps by Ibackshift; JN316 @ 57 grams

The Ski-Doo pDrive clutch ramp [JN316] by Ibackshift quickens the engine speed up over stock ramps.  Minimizes lag and help you wheelie through the trees.

Ski-Doo pDrive clutch ramps by iBackshift specifically designed for the Ski-Doo 850 turbo.
Can be used with the stock Ski-Doo 850 turbo engine, or Ski-Doo 850 turbo with tune, tuner, tunes.

When the power is added at 8000 rpms, there is a loss of torque between that lower engine speed range. The most common issue when going to a Ski-Doo 850 turbo tune or Ski-Doo 850 aftermarket turbo, is the power loss between 3500 and 6500 rpms. Most vehicles with these upgrades [depending on tune brand] can give you a bog in the bottom end.

Ski-Doo 850 turbo CLUTCH SPECS
The 2024, 23, 22, 21 Ski-Doo 850 turbo uses the 951[49.3g] pDrive ramp from 0~3000 feet
The 2024, 23 Ski-Doo 850 turbo uses the 761 [52.4g] pdrive ramp from 3000 to 10000 feet
The 2022, 21 Ski-Doo 850 turbo uses the 994 [49.2g] pdrive ramp from 3000 to 10000 feet
The 2020 Ski-Doo 850 turbo uses the 984 [50.9g] pdrive ramp from sea level to 12000 feet
The 2024, 23, 22, 21 Ski-Doo 850 turbo uses the 903 [50.0g] pdrive ramp from 10000 to 12000 feet

The Ski-Doo pDrive clutch ramps by Ibackshift, model #JN316 yep, you read that right, "JN316" he he :) is 57 grams. This Ski-Doo pDrive clutch ramp by Ibackshift has the mass to handle over 220hp. It's more heavy than the 761 pdrive ramp on-purpose, to handle the Ski-Doo 850 turbo with tune, tuner, tunes.

***The Ski-Doo pDrive clutch ramp 965 is a lousy profile to use for Ski-Doo 850 turbo stock or with tunes and, Ski-Doo 850 aftermarket turbos.  If you want your clutching to make the engine sound like "a mooing cow" when you press full throttle, go ahead and use that 965 profile, HAHAHA***

IF the 965 were any good for the power shape of a turbo engine, THEN BRP would have used them.

With the correct pivot bolt weight, you can use this iBackshift ramp for ALL elevations.

The challenge was to develop a Ski-Doo pDrive clutch ramp for the more complex horsepower power tunes. In a rapidly increasing demand for more power, I needed to have an intuitive Ski-Doo pDrive clutch ramp solution.

Ski-Doo 850 turbo tune and, Ski-Doo 850 aftermarket turbo; PROBLEM
When an owner installs a Ski-Doo 850 turbo horsepower tune, or, a Ski-Doo 850 aftermarket turbo; many brands end up losing engine torque levels between 3500 and 6500 rpms.

CAUSE
As the power is increased, A turbo lag is introduced.
IF you increase the horsepower at the original power peak rpms [example] 8000 rpms, THEN you lose engine torque between 3500 and 6500 rpms. Some tune brands are better than others for maintaining torque as best it can in that rpm lag range.

SOLUTION
The iBackshift ramp is designed to help the engine rev up through that lag, and still have nice engagement speed with lower engine speed at part throttle in both cases of Ski-Doo 850 turbo [factory] and Ski-Doo 850 aftermarket turbo.

DEVELOPMENT
From knowing how each Ski-Doo pDrive clutch ramps run, I was able to grind ramps using my trusty spindle sander. I figured out a good roller profile, matching these kinds of power outputs.
The Ski-Doo pDrive clutch ramps by Ibackshift starts with a base 903 profile. I shaved the start of the profile down to be in between a 903 and a 761. At about 20~25mph track speed, the profile blends to the 903 profile across the midrange. From about 2/3 of the profile to maximum top speed, the profile curves down with the manner of a 761.

SIMULATION
That ramp knowledge allowed me to simulate the Ski-Doo pDrive clutch ramp I thought would match the power profile of the Ski-Doo 850 turbo tunes and Ski-Doo 850 aftermarket turbo.

TESTING
After testing every BRP ramp, I made versions of the JN316 Ski-Doo pDrive clutch ramp and ran them myself to firm up the ramp profile.

VALIDATION
With the collaborative effort from Ski-Doo 850 turbo test owners, our Ski-Doo pDrive clutch ramps were sent out and executed in Ski-Doo 850 turbos and Ski-Doo 850 aftermarket turbo sleds.

When running hard, off and on full throttle in the tight trees, the engine speeds up quicker, the ski lift is more abrupt. When you land, coming to a dead stop in front of a tree, the rider can steer away from the tree, go full throttle, the sled lifts and goes around the trees. When you sidehill and have to get between the trees, time it right, full throttle, engine speed rises quick, sled lifts and squeeze an angled wheelie between the trees.

If you buy with an iBackshift Ski-Doo 850 turbo clutch kit and want these JN316 ramps included, the ramps are 10% off with the kit. I'll make the adjustment in the background after the sale.