Drive Error on ST2

ST2

New Member
I took advantage of removing the rear wheel to fix a flat a flat rear tire to rotate the tires, true the wheels and discs, and give the bike a good cleaning.

After doing so, I mounted the front wheel fine.

The rear wheel was giving me some grief, but I managed to simultaneously line up the disc in the calipers, chain on the smallest cog and set the connectors to the pins for the motor while mounting the rear wheel. Getting the thru axle threads to bite was a bit of a challenge but managed eventually.

Started to go for a test ride and turned on the computer which indicated a charge of 100% and assist mode of 3. As soon as I started rolling, it notified "Drive Error". The next screen said to reset the battery by removal and re-installation. Did so and got the same result again.

The pins were connected and the half-ring was closed, so I don't think it was the installation.

Any ideas?

Thanks!
 

Ravi Kempaiah

Well-Known Member
I took advantage of removing the rear wheel to fix a flat a flat rear tire to rotate the tires, true the wheels and discs, and give the bike a good cleaning.

After doing so, I mounted the front wheel fine.

The rear wheel was giving me some grief, but I managed to simultaneously line up the disc in the calipers, chain on the smallest cog and set the connectors to the pins for the motor while mounting the rear wheel. Getting the thru axle threads to bite was a bit of a challenge but managed eventually.

Started to go for a test ride and turned on the computer which indicated a charge of 100% and assist mode of 3. As soon as I started rolling, it notified "Drive Error". The next screen said to reset the battery by removal and re-installation. Did so and got the same result again.

The pins were connected and the half-ring was closed, so I don't think it was the installation.

Any ideas?

Thanks!

Sounds very familiar what I have experienced quite a few times.
Now, do you have a torque wrench?
The thru axle should be right at 20Nm. You can go +1 or 2Nm above but if you go lower, torque sensor won't be able to calibrate itself effectively.

Go back, remove the rear wheel making sure you do not pull the motor cable. Reinsert the motor power cable, align the axle, and retighten the thru axle to 20Nm.
Once the bike is powered on, reset the TMM4 by going to the service menu. My hunch is that power cable is not fully seated and the TMM4 is off.

Also, install some liners to prevent future flats. Or better, install a Schwalbe Marathon Plus 26x2" w/ liners. You won't have to deal with quite as often.
 

ST2

New Member
Thanks, Ravi; I'll give it another go tonight as I'd only hand tightened it and it's likely the torque sensor as you mention.

I'll get the Marathon Plus tires as well; Are there variations of them that are rated for e-bikes or are they all the same?
Which liners would you recommend? Not familiar with them.
 

smitty

Active Member
Sounds very familiar what I have experienced quite a few times.
Now, do you have a torque wrench?
The thru axle should be right at 20Nm. You can go +1 or 2Nm above but if you go lower, torque sensor won't be able to calibrate itself effectively.

Go back, remove the rear wheel making sure you do not pull the motor cable. Reinsert the motor power cable, align the axle, and retighten the thru axle to 20Nm.
Once the bike is powered on, reset the TMM4 by going to the service menu. My hunch is that power cable is not fully seated and the TMM4 is off.

Also, install some liners to prevent future flats. Or better, install a Schwalbe Marathon Plus 26x2" w/ liners. You won't have to deal with quite as often.
That is some pretty (very) useful info Ravi. Quick question, how does one get to the "service" menu on an ST-2 and what does TMM4 refer to...I'm guessing, that it is in reference to the torque sensor?
 

Ravi Kempaiah

Well-Known Member
That is some pretty (very) useful info Ravi. Quick question, how does one get to the "service" menu on an ST-2 and what does TMM4 refer to...I'm guessing, that it is in reference to the torque sensor?
When you go the menu screen on the OMNI, if you hold the right brake lever and press on the menu simultaneously for 5 seconds and then release only the brake lever before releasing your finger from the menu icon, you can get into the service menu.
So, basically, hold the right brake lever and press menu icon for 5 seconds and release the lever. Then, once you go to service menu, press on torque sensor.The TMM voltage and the offset voltage should be fairly close. If there is a large offset, then you can press the "reset" TMM4 icon.
 

smitty

Active Member
When you go the menu screen on the OMNI, if you hold the right brake lever and press on the menu simultaneously for 5 seconds and then release only the brake lever before releasing your finger from the menu icon, you can get into the service menu.
So, basically, hold the right brake lever and press menu icon for 5 seconds and release the lever. Then, once you go to service menu, press on torque sensor.The TMM voltage and the offset voltage should be fairly close. If there is a large offset, then you can press the "reset" TMM4 icon.
Thank you Ravi. I haven't felt the need for getting to the service menu at this point but the query above reminded me that I have yet to remove the rear wheel and I'm thinking that I should rotate the tires (700 miles). I did purchase a torque wrench, so the tip on tightening the axle bolts for the reasons you stated was very helpful too...thank you again.
 

ST2

New Member
(Link Removed - Attachment No Longer Exists)
When you go the menu screen on the OMNI, if you hold the right brake lever and press on the menu simultaneously for 5 seconds and then release only the brake lever before releasing your finger from the menu icon, you can get into the service menu.
So, basically, hold the right brake lever and press menu icon for 5 seconds and release the lever. Then, once you go to service menu, press on torque sensor.The TMM voltage and the offset voltage should be fairly close. If there is a large offset, then you can press the "reset" TMM4 icon.
Hi Ravi, Re-inserted the rear wheel and got the thru axle torqued to 20nm. Thanks for the info on the TMM4 as well :)

I'm trying to get into the Service menu and am holding in the right (rear) brake lever and the menu icon simultaneously for 5 seconds and then releasing the brake lever and then releasing my finger from the menu, but I'm not seeing any change. I tried several times with the icon and then tried with the word "menu" at the top of the submenu in case. Not getting to the service menu for some reason. Am I missing something?
 

ST2

New Member
I haven't felt the need for getting to the service menu at this point but the query above reminded me that I have yet to remove the rear wheel and I'm thinking that I should rotate the tires (700 miles).
Yes, my OG Big Ben tires are at 666 miles (maybe that's my problem ;) and on the rear tire the diamond tread was worn flat on the middle and starting down the sides, while the front tire looked almost new. I'd bet the weight distribution is something like 80% rear and 20% front on the bike, especially with the Macbook Pro in one pannier and lunch and a change of clothes in the other.
 

Ravi Kempaiah

Well-Known Member
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Hi Ravi, Re-inserted the rear wheel and got the thru axle torqued to 20nm. Thanks for the info on the TMM4 as well :)

I'm trying to get into the Service menu and am holding in the right (rear) brake lever and the menu icon simultaneously for 5 seconds and then releasing the brake lever and then releasing my finger from the menu, but I'm not seeing any change. I tried several times with the icon and then tried with the word "menu" at the top of the submenu in case. Not getting to the service menu for some reason. Am I missing something?
It will be at the bottom of the screen.
 

Neil

Member
If you hold on to the right brake lever and press the menu , release the right brake lever and keep holding the menu key for 5 seconds, then the options will pop up, scroll to the bottom and now you see an option called service. you can now go into service menu.
 

Neil

Member
Good to hear. My ST2 is dead in the water right now. I have a system error and drive error message and cannot clear it by removing battery. I thought it might be what Ravi suggested as I had recently changed brake pads. Took the wheel off and checked the torque of the back wheel and it was correct. Still have the error. Waiting for Joel at Stromer to get back to me. Ther error codes I gave him indicated no battery present and a controller issue. Controller was just replaced so who knows what the issue is. Frustrating!!
 

ST2

New Member
Good to hear. My ST2 is dead in the water right now. I have a system error and drive error message and cannot clear it by removing battery. I thought it might be what Ravi suggested as I had recently changed brake pads. Took the wheel off and checked the torque of the back wheel and it was correct. Still have the error. Waiting for Joel at Stromer to get back to me. Ther error codes I gave him indicated no battery present and a controller issue. Controller was just replaced so who knows what the issue is. Frustrating!!
Yeah, mine's in the shop getting authorized repair service at this point. Provided error codes and was told it needed professional attention. I had no idea the removal of the rear wheel voids warranty! Certainly not indicated on (Link Removed - No Longer Exists).
 

smitty

Active Member
Wow...that is hard to believe; makes me think the dealer might be giving you the run-a-round. I mean if one gets a rear wheel flat, you certainly would have to remove the tire to repair it and you are right, the instructions for doing so are well indicated in the Stromer ST2 manual...what gives here?
 

ST2

New Member
@smitty Yes, agreed pretty unbelievable. Haven't found the fine print stating as much yet. If true, it makes me think I'd need the Roadside Assistance from Velosurance just to stay compliant!
 

britannic

New Member
There's no other way to field repair the rear tire without wheel removal, hence the instructions in the manual. However, in the event of an issue, this bullet in the warranty could be applied:

  • Repairs that have not been carried out by trained specialists