Drum Scraping and Stalling/Jamming at 300+ Degree Temps

Hi everyone,

I’m hoping to receive some community help on a physical issue with my Bullet R1 V2. When preheating the drum, it will start scraping the front of the unit at around 300 degrees Fahrenheit. If left long enough, the scraping gets so intense that the drum stalls completely, and an awful da-da-da-da sound happens. I believe it gets jammed at that point and is unusable.

I’ve attempted to adjust the pulley, tighten the belt, and added two shims to support the bearing.

Has anyone experienced this? If so, how did you overcome it? I’ve reached out to Support but wanted to cover it with the community as well.

Jamie Favreau

The Bullet should have come with extra spacers of different thicknesses to be used to adjust the clearance between the drum and the faceplate.

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Hey Warren,

Thanks for the recommendation. If I’m already using the two extra spacers should I pick up more, or might there be something else wrong?


A couple thoughts-

Just to confirm: do you mean the 2 spacers that were (I’m guessing here based on my own Bullet V1.5) factory installed? or that you already inserted the 2 spares packed with the roaster? The spares are provided in case you run into the need for adjustment, but if you now have 4 spacers installed there is likely a different issue.

  • is the scraping sound from the front of the drum? if it is…
  • have you confirmed there isn’t any debris/broken beans between the drum and the face plate?

If there’s too much space at the front it will allow small beans to drop into the gap where they make a horrible racket till the front plate is removed and the broken bits cleaned out

  • is the drum shaft seated all the way forward into the bearing? if it isn’t that leaves the possibility the drum is rubbing at the rear

If the sound is from the rear, I don’t have any personal experience digging into that but you might check the drum-mounted cog belt pulley on the rear of the drum shaft to confirm it isn’t rubbing against the rear plate. Or even possibly contact between the motor-mounted drive pulley and mounting hardware (belt tension adjustment has changed since I received my V1.5 so I’m not familiar with your configuration).

And just as a point of reference I have a little scraping noise from the drum lightly rubbing the front plate for a about a 20-40 sec as the roaster Preheats, then the sound disappears. Increasing the spacing to stop that noise lets small beans drop into the space during a roast so I learned to deal with it.



Did you check that the set-screw for the handle is not protruding in the door? make sure it is flush with the door frame.

I’m experiencing the the same issue. Once the roaster is heated, I start to hear grinding at the front. I have checked the set screw on the door handle and removed the face a few times to clean any stuck beans. I actually had the roaster drum stop about 1 minute in on a roast. The drum was not slipping but appeared and sounded like it was stuck. I was able to push on the bearing with the back of hex tools furnished with roaster and alleviate the systems for a second. It appears that I may need the spacers described in this thread. I will check the tension on the belts too. I feel like the shaft that rotates the drum has to mush play and moves front to back too much, hence why I think the spacers are needed. When I checked the bearing it appears I only have one spaces (washer set behind the bearing). I can not find other spacers manery I lost one, but do not remember extra’s in box. Any input would be greatly appreciated . Thank you. Did spacers fix the problem?

Was this issue resolved somehow? Experiencing the exact same problem as described in the post.
The Bullet has been working fine up till now…

Best regards,

Did you do any cleaning / adjustments prior to this happening?
If the scraping is coming from the front it could mean adding a shim (see the manual). Could also be beans under the drum. From the back of the roaster check the big drum pulley is not too close to the chassis.

Thank you for the input.
I have just started roasting on the bullet so no deep cleaning done yet. But I will open the machine up and try the suggested options.