03A-2 A500309 Large Sprocket 22T for MX48 Power Feeder OD68.5mm ID30mm Thickness 5.3mm Bolt Hole 6.82mm 80.9g

Need the large sprocket that drives an MX48 power feeder chain? The 03A-2 A500309 carries 22 teeth on a 68.5 mm outside diameter, with a 30 mm bore, 5.3 mm thickness, 6.82 mm bolt hole and 80.9 g net weight. It bolts to the existing hub at the original diameter and engages the chain in the same position as the old part, so a worn sprocket is cured with one piece instead of a whole drive assembly.

A power feeder that has run for a few seasons usually shows three symptoms before anyone acts on them: the feed rate drifts a little further every month, the chain starts to climb the sprocket rim instead of sitting down in it, and the drive chatters under load. Shops then pick between three expensive options — keep running it, send the feeder out for repair, or buy a complete drive assembly to recover one worn gear.

The 03A-2 / A500309 is the large sprocket (22T) for that position on an MX48 power feeder. It carries 22 teeth around a 68.5 mm outside diameter, a 30 mm inner bore and a 5.3 mm plate thickness, which leaves 19.25 mm of steel between the bore and the rim on each side.

The bolt holes are drilled at 6.82 mm, so the sprocket bolts to the hub at the original diameter instead of being re-drilled on site, and the 22-tooth ring picks up the existing chain at the same centre distance. Shaft, hub and chain stay as they are.

It is machined from high-strength wear-resistant steel and weighs 80.9 g per piece. One sprocket per position is all that is supplied and all that is normally needed: no chain, no hub, no bearing. Origin: China; price on request.

What the part is, in the order a buyer checks it against the old one:

• 22 teeth, same count as the original. The chain engages on 22 teeth, so the sprocket turns it at the ratio the feeder was set up with.
• 68.5 mm outside diameter. Measured across the rim; a sprocket that matches 68.5 mm drops into the same space the old one came out of.
• 30 mm bore. Slides onto the standard drive shaft without reaming, sleeving or machining the bore out to size.
• 5.3 mm plate thickness. The plate is 5.3 mm, so the new part takes the same axial space on the shaft as the worn one.
• 6.82 mm bolt holes. Drilled at 6.82 mm, so the existing bolts and the original bolt circle are reused and nothing is drilled out on site.
• 80.9 g per piece. Light enough to slide onto the shaft by hand, and light enough to keep one on the shelf as the next spare.
• High-strength wear-resistant steel. Machined from wear-resistant steel, so the 22 tooth flanks keep their profile through continuous feed load rather than rounding off.
• Single-piece replacement. One sprocket per position — no chain, hub, bearing or adapter is ordered with it.
• Two part numbers, one part. 03A-2 and A500309 both identify this sprocket, so a printed parts list matches whichever number it carries.

When the sprocket wears, the choice usually comes down to feeding on with a drifting rate, sending the feeder out, or buying the whole drive assembly. One sprocket removes all three.

• Replace the worn part only. The sprocket is the part the chain rides on, so a worn rim is cured with an 80.9 g part, not a drive assembly.
• A feed rate you can set and repeat. With 22 teeth engaging the chain at the original centre distance, the setting you dialled in still means the same feed tomorrow.
• Same footprint on the shaft. 68.5 mm outside, 30 mm bore and 5.3 mm plate means the new sprocket takes the place of the old one with no shims and no spacers.
• Downtime measured in one shift. One part, one position, and the original bolts go back into the 6.82 mm holes.
• Cheap to keep in stock. At 68.5 mm and 80.9 g, a spare takes a corner of a drawer, so the replacement is there when the rim goes.
• Verifiable before you fit it. Four measurements — 68.5 mm, 30 mm, 5.3 mm and 6.82 mm — plus the 22-tooth count confirm the part against your old sprocket with a caliper.
• Reorderable from an old parts list. 03A-2 and A500309 are both on the part, so a reorder from a printed list matches whatever number it carries.

Yes, if your drive takes the 22-tooth large sprocket. The 03A-2 / A500309 is listed for the MX48 power feeder with a 68.5 mm outside diameter, 30 mm bore and 5.3 mm thickness; measure your old sprocket against those three figures before ordering.

Yes. Both numbers identify this large sprocket. Use whichever number your parts list, manual or old invoice carries.

Measure four things on the old sprocket: 68.5 mm outside diameter, 30 mm bore, 5.3 mm thickness and 6.82 mm bolt holes, then count 22 teeth. Net weight is 80.9 g if you want a second check on a scale.

Yes. This is the large sprocket: 22 teeth, 68.5 mm outside diameter, 80.9 g. If your old part measures less than 68.5 mm across the rim, it is a different sprocket.

Usually a worn tooth rim. As the 22 tooth flanks wear, the chain sits lower on the rim and starts to ride up instead of staying in the seat; a new sprocket puts the tooth profile back to the original shape.

High-strength wear-resistant steel. It is a machined steel sprocket rather than a cast or plastic wheel, which is why the tooth flanks hold their profile under continuous feed load.

No. Only the sprocket is supplied and only the sprocket normally needs replacing. The chain, hub, shaft and bolts stay on the machine.

80.9 g per piece. Price is quoted per order: send the part number 03A-2 / A500309 and the quantity you need, and a quote comes back.