New Holland 980CR Upgrade kits

The Calmer upgrade kit solves many
of the mechanical problems with the
new holland 980cr corn heads.
These parts enable this head to perform
better than new at a fraction of the cost
of a new or chopping corn head.
100% satisfaction guaranteed!

BT Chopper Stalk Rolls

Through the integration of multi-length blades,
Calmer Stalk Rolls have a patented “open window”
feeding chamber, which guarantees the efficient
flow of cornstalks into the row unit to
become processed into “confetti-like” pieces
by 20 razor-sharp blades.

Multi-Zone Beveled Stripper Plates

Our patented stripper plates have a wider
front opening to help prevent the bulldozing
of cornstalks when slightly off the row. The
beveled stripping area mimics the bottom
portion of the corn ear to reduce
butt shelling problems and trash intake.

Oil Bath "Slow Down" Sprockets

Calmer’s new oil bath sprockets
slow down the entire corn head
to help decrease both ear bounce
and butt shelling problems that occur
when the corn head is running too fast.

gathering chain sprockets Refined

calmer gathering chain drive and
idler sprockets better synchronize
gathering chain speed with stalk roll
 speed to allow cornstalks to travel
efficiently into the row unit. 

Calmer Grass Knives

Calmer offers a redesigned grass knife
that helps prevent the back warpping of
grasses around factory nose cones.

new holland 980cr
Series Kit

Follow along with Marion as he explains the Full Calmer BT Chopper® Upgrade Kit offered for the New Holland 980CR corn heads. These patented corn head parts will turn your underperforming factory corn head into a top performing machine while also making you more money in the process by reducing a pass across the field, eliminating the chopping of stalks, improving planting operations, and increasing yields.


the Case 4000
is mechanically similar
to your New Holland 980CR

Available to ship Summer 2021


follow our recommended steps for maximum performance

Step 1



Reliable stalk rolls are critical to a top-performing corn head. That’s why Calmer invented the World’s Only All-Weather Stalk Roll™ known as the BT Chopper®, which is the only roll in the industry with a patented “open window” feeding chamber for the superior feeding and processing of stalks in all crop conditions. 

The 10 razor-sharp knives on each stalk roll cut, chop and shear cornstalks into confetti-like pieces for accelerated decomposition. As a result, you’ll be able to reduce a management pass across the field, improve your planting experience and increase yields. Calmer Grass Knives match the curvature of the  BT Chopper’s® redesigned nose to  prevent the back wrapping of grasses.



multi zone beveled stripper plates from calmer features

“We wanted to do some testing ourselves so we ran 1 row of the Calmer BT Crushers, 1 row of brand new Deere rolls, and one row of modified Deere rolls. We would see the rusher rows with no problem. Now we want to go to the Choppers on all 8 rows because we plant beans into corn stalks—It will be even easier with no stalks.”

David Ericson

Reynolds, IL


Reduce Butt Shelling and

Decrease “Trash” Into Combine

Calmer’s Patented Multi-Zone Beveled Stripper Plates are design with a wider front opening to minimize the bulldozing of cornstalks when not fully aligned with the row. This wider retrieving area is manufactured flat to reduce ear wedging problems and beveled in the back stripping area to allow the stalk rolls to engage the ear shanks, leaves and husks, which significantly reduces trash intake into the combine. The patented beveled edge also better mimics the rounded  corn ear to reduce kernel loss by displacing the energy around the base of the corn ear.


Accelerator gathering chain Sprockets 

drive and idler sprocket for chain timing case 4000

By speeding up gathering chains by 18% with Calmer’s larger 13-Tooth Drive Sprockets, stalk roll speed is better synchronized to gathering chain speed. This allows for more of the plant to be processed at the corn head and prevents the gathering chain lugs from inhibiting the entry of the cornstalks as they travel into the row unit. 

Calmer’s smaller 13-Tooth Idler Sprockets allow for a factory chain to be utilized by maintaining the same chain envelope as factory corn heads. 

“The performance of the two rows with the BT Chopper rolls is phenomenal. Thanks for your recommendation at the No-Till Conference. I will get the rest of my rows upgraded with the BT Chopper Trash Reduction Kit this winter. Thanks for helping me get my old equipment up to modern standards.”



– Jonathan Hess
Lancaster, PA


Oil Bath “slow down” sprockets

oil bath sprockets for NH980CR

The stalk roll tip speed on New Holland 980CR corn heads is too fast. This often causes excessive ear bounce and butt shelling problems. 
To solve this issue, Calmer invented oil bath sprockets to slowdown the entire corn head, decreasing the ear bounce and butt shelling issues caused by excessive head speeds.

(Oil Bath “Slow Down” Sprockets are not available for NH 980CR folding corn heads or for 20- and 22-inch corn heads.) 


Big picture Economics

Follow along with George as he explains his thought process behind the economics of maintaining his corn head with Calmer BT Chopper® Stalk Rolls and Residue Management Performance Parts.

Complete the ROI plan to see how



 No Feeding Chamber

Factory New Holland stalk rolls are unable to perform effectively without an area for stalks to enter the row unit. Because the stalk rolls on these corn heads have the same length flutes, there is a constant overlap in the entry area, which prevents the the entry of cornstalks.

Mechanically, this flawed design results in the premature wear at the front of the stalk rolls while the remaining length of the roll remains in “like new” condition since stalks can’t travel into the row unit.

CASE IH stalk roll design problems

Cornstalks CANNOT engage with factory rolls or become processed due to the continuous overlap in entry area.


Patented “Open window” Feeding Chamber

The multi-length blades incorporated into the Calmer BT Chopper® Stalk Rolls enable the New Holland 980CR to process cornstalks more effectively than a chopping corn head.  Mechanically, this design enables cornstalks to travel efficiently into the row unit to become cut, chopped and sheared into “confetti-like” pieces. 

This stalk roll performs in all crop conditions, guarantees the traction and processing of stalks, lasts longer, prevents the bulldozing of stalks at the end rows and makes planting and tillage operations easier. 

Cornstalks EASILY engage with Calmer’s patented “open window” feeding chamber to become processed.



 Limited Residue-to-Soil Contact

Stalk rolls for New Holland 980CR corn heads have an overlap in the entry area which prevents cornstalks from fully engaging with the knives to be processed. As a result, additional tillage passes are necessary to properly manage cornstalks prior to planting.

Failing to properly process cornstalks into small pieces prevents residue-to-soil contact, leading to the immobilization of important nutrients on the soil surface, slower degradation rates and a wet mattress of residue in the spring.

Cornstalks failed to enter the knife chamber, resulting in little residue-to-soil contact and slow decomposition rates.


10 intermeshing Razor-sharp blades

 Superior Residue-to-Soil Contact

During rotation, the shortened flutes on the Calmer BT Chopper are timed to create 2, 4-inch feeding chambers for an efficient handoff of the stalk into the 17 1/2-inch knife chamber to be processed.

In the knife chamber, 20 intermeshing, razor-sharp blades cut, chop, and shear cornstalks into confetti-like pieces. Calmer BT Choppers® expose the pith of the stalk and places the residue strategically over the row for superior residue-to-soil contact, accelerated decomposition, easier planting and higher yields!

Cornstalks are easily engaged and processed for superior residue-to-soil contact and rapid decomposition..



Factory New Holland 980CR series stripper plates are not formed to match the natural shape of the bottom side of the corn ear which causes kernel loss upon impact by displacing all the energy on one kernel.

As shown in the image below, the additional welded bar along the edge of these plates is problematic because it protrudes above the plate’s edge, causing additional kernel loss.

This design also fails to allow the ear shank to get close enough to the rolls to become processed.  This results in the husk staying attached to the ear and sends it and more material other than grain (MOG) into the combine.

Straight stripper plates don’t emulate the bottom portion of the corn ear, increasing butt shelling and trash intake.


Patented Multi-Zone Beveled Stripper Plates

Calmer’s Patented Multi-Zone Beveled Stripper Plates are flat in the front retrieving area to reduce ear wedging and beveled in the stripping area to allow the stalk rolls to engage more ear shanks, husks, and leaves, and to reduce trash intake into the combine. The wider front opening helps prevent the pushing of stalks when slightly off of the row. 

The patented bevel matches the rounded butt of the corn ear. This does a better job at displacing the energy that contributes to kernel loss.

These beveled stripper plates have a weld- hardened surface for extended life. 


Case 4000 stalk roll parts


slow gathering Chain Speed

Synchronizing gathering chain speed to stalk roll speed is essential to processing more of the corn plant at the corn head. 

Gathering chains on factory New Holland 980CR corn heads utilize gathering chain speed ratios that are too slow. At these slower speeds, the chain lugs inhibit the entry of cornstalks.   


patented accelerator kit

Calmer’s 13-Tooth “Accelerator” Drive Sprockets increase the speed of gathering chains by 18%. This adjustment better synchronizes gathering chain speed to stalk roll speed to allow the stalk rolls fully process cornstalks directly at the head. This also helps prevent the gathering chain lugs from inhibiting the entry of cornstalks as they enter the corn head. 

Calmer’s smaller 13-Tooth Idler Sprockets maintains the same factory chain envelope to allow for an OEM chain to be utilized on Calmer Sprockets.  


Fast Corn Head Speed

New Holland 980CR corn heads utilize excessive stalk roll tip speeds that cause excessive ear bounce and butt shelling issues.   


Calmer “slow down” oil bath sprockets

Calmer sells patented “slow down” sprockets for the New Holland 980CR corn head to reduce the tip speed of the stalk rolls by slowing down the entire head. This will reduce ear bounce and butt shelling problems associated with the corn head.

Get MORE than you bargained for this fall with Calmer's BT Choppers® and Residue Management Upgrade Kits

With Calmer Upgrade Kits, you're getting more than just corn head parts, you're getting peace of mind that your residue management and corn head problems are solved for good during harvest. 


Agronomic and Mechanical Advantages

Mechanical Advantages

    • Compatible with all Tillage Systems
    • 25% Less Hp Needed than with Chopping Heads
    • Superior Cornstalk Flow to Engagement
    • Better Ear Separation
    • Less Tire Wear
    • Less Butt Shelling
    • Increased Harvesting Speeds (Achieved through a combination of installing Calmer® products and proper combine settings)
    • Lower Spread Load

Agronomic Advantages

    • Unmatched Residue Decomposition
    • Warmer Soils
    • Drier Soils
    • Increased Earthworm Populations
    • Reduced Nitrogen Penalty
    • Easier Planting
    • Higher Yields
dave hula reccomends calmer stalk rolls

Still not convinced?

Look at the Benefits on The Ground

the testimonials and scientific studies show how valuable residue is when properly managed. Maximize its worth by managing it with calmer stalk rolls.