Bullet R2 Pro – Managing Tipping in 1-1.2kg Batches

R2 & R2 Pro Specific
1

Hi everyone,

I’ve been experimenting with the Bullet R2 Pro for about a month and wanted to start a discussion on the best approach for roasting 1-1.2kg batches.

I’m bringing this up because I’ve encountered some tipping issues and want to raise awareness within the community.

My Experiments:

  1. First Attempt (1.2kg Batch)
  • Charge Temp: 300°C
  • Initial Power: P13
  • Initial Fan: 3
  • Drum Speed: 9

I followed an approach similar to gas roasting—gradually reducing power while increasing the fan until first crack (9:10), then further reducing power afterward. The total roast time was 11:19, with an end temp of 217°C (which I find quite high). The graph looked great, but under UV light, I noticed tipping throughout the batch.
2. Second Attempt (Same Parameters, Closer Monitoring)

  • I repeated the roast while checking the beans every 5-10 seconds with the tryer.
  • I discovered that tipping occurred around 170°C, roughly in the middle of the roast.
  1. Third Attempt (Adjusted Approach to Prevent Tipping)
  • Charge Temp: 265°C
  • Power Level: P12
  • Fan: 5
  • Drum Speed: 9

This time, I kept the fan at 5 until around 170°C and gradually reduced power to P9 before reaching that point. This adjustment eliminated the tipping issue but slowed down the roast. First crack occurred at 10:36, and the total roast time extended to 13 minutes.

Next Steps:

My next experiment will focus on increasing the charge temperature and power to shorten the drying phase while still avoiding tipping.

Now, I’d love to hear from you! What’s your experience with larger batch sizes, and how do you approach them?

2 Likes
2

Hello,

It sounds like you have done a wonderful job in identifying and mitigating the problem. I’m writing only to share that I also experience tipping on my R2 Pro, but with smaller batches of 450g and a power level that never goes above P9 for pre-heating and quickly declining to P5-6 throughout the roast.

Following the traditional wisdom on avoiding tipping from Rob Hoos, I increased my airflow to F5 from the beginning of the roast and kept it there to the end. The only change I make to airflow is to ramp up the fan to F12 right before dropping the beans to get as much of the chaff out as possible before dropping. Otherwise, the continual higher fan speed made a difference in minimizing tipping.

There are still some roast defects from time to time, like light scorching on some of the beans (presumably from the hot drum, even though the drum is always at D9). I’m still figuring out the machine and its (or perhaps my) idiosyncrasies.

1 Like
3

I had to Google it. Tipping is when the ends of the coffee bean get scorched or burnt. I thought I’d save everyone else the detour. :slight_smile: