Stuck on max resistance

[ChrisH]

Hi All,

I have a Real Turbo Muin B+... was working fine until recently. Upon starting, the trainers pump / motor wound up as it usually does, but it stayed on for longer than usual, and appears to have wound to maximum resistance. You can barely move the thing. No normal tricks of restarting, repairing, different software have made any difference at all.

Any suggestions? I know the answer will be 'contact support' but it would be helpful if the forum had more solutions on it not just that. I have seen similar posts before but not with solutions so I'm obviously not the first person to have this issue.

I'm one step away from opening it up and seeing if anything is stuck.

Thanks,

Chris

[ChrisH]

Ok, in an effort to get some solutions on here not just questions... sorry for the jab... I am back up and running.

The problem was that the brass gear that the motor drives to vary the resistance had come detached from the magnets. This meant the motor just span and the brass gear span on the shaft. It ended up on max resistance I guess because the pull of the magnets basically moved that to the hardest setting.

The tell tell sign was obvious to spot with just the smaller of the two plastic covers removed. This revealed that a piston - that quite clearly was supposed to move - wasn't moving and indeed it felt loose to the touch. The piston is supposed to move with the magnet assembly and triggers a microswitch at one extreme of the movement, this is obviously integral to the opening configuration routine the trainer goes into on power up. The reason it made the winding noise for longer than usual as I described in my first post, was because the piston wasn't moving and thus never got close to touching the microswitch.

Anyway, fixing it was quite easy, a few things had to come apart to get access but essentially it was a case of refitting and tightening a grub screw that had come loose. There was no apparent sign of threadlock on the grub screw - maybe the person assembling mine ran out - but I cleaned and applied some on re-fitting so hopefully it won't come loose again.

I also clean the bearings for the magnet adjustment mechanism. Unless mine have worn badly these are very poor quality btw... not smooth at all. Fortunately they will never really move that quickly so I guess it's not critical, but they weren't the highlight of the engineering show. When cleaned and re-greased they were slightly better... slightly.

I was careful to re-assemble each part with care, applying threadlock on the key areas. Note, the aluminium housing could be stripped quite easily with too much torque so things need to be tight... but not too tight. I paid special attention also to grease all o rings etc.

The most time consuming thing to complete was removing the old gasket / sealant from the main housing. I wanted to make sure this was really clean so I would have a leak proof seal. Anyway, tick.

Unit is back up together now and working properly again! Phew...

Final question... oil... I would love to know the quantity and spec? Mine leaked a small amount a year ago so whilst doing this I topped up a very small amount (roughly what I considered to have lost) of a similar viscosity (I thought relatively thin) mineral oil. This seems to be fine, but I have read different views that the oil is either synthetic oil or a silicone oil. If it's a silicone oil, I am concerned that it may not mix well with the mineral oil I added. I only added a small amount - I guess less than 10% total volume) so I am not expecting any major ill effect... but if I know what the correct type and quantity is I will pop the cover again, flush it out and refill to original spec in entirety.

Any info on this?

Then the final challenge will be to check power calibration... but I believe I am right in saying I will need another power meter for this, which is annoying. But on a first test tonight, it seems about right or at least in line with how I remember it being when new (it had deteriorated a bit in it's responsiveness presumably because of the marginal fluid loss but also I think the gear had been getting gradually loser for some time).

I have pictures if it would help anyone but I won't mess around uploading unless the thread gets some traction.

Oil info gratefully appreciated!

Thanks

Chris

[jsalcone]

Hi Chris - I have a new Zumo smart trainer. It worked great the first three times, then I unplugged it, moved to a different room, and tried to ride tonight. It was stuck on maximum resistance. I manually moved to an easy gear so I could turn it and tried multiple times to run the “configure” in the app - it would not configure and I got a burning clutch smell from spinning it against all that resistance.

I cannot find how to do a “rundown” test, and I am out of other options. Should I take it apart like you did?

Thanks,

Jake

[aria.nemati]

I have the same problem on my Zumo. I bought a "new unit" that was probably returned to the store because of it. The resistance is too high, even on the lowest setting. On Zwift, my avatar is barely moving, my legs get destroyed after a couple seconds. If I do a spin down calibration on the elite app, I am asked to start pedaling and then increase speed, when I increase speed, there is a chemical burning smell coming from the trainer. I cant calibrate because I cant keep up. The resistance is too high and I am unable to finish the calibration.

[aria.nemati]

Hi Chris - I have a new Zumo smart trainer. It worked great the first three times, then I unplugged it, moved to a different room, and tried to ride tonight. It was stuck on maximum resistance. I manually moved to an easy gear so I could turn it and tried multiple times to run the “configure” in the app - it would not configure and I got a burning clutch smell from spinning it against all that resistance.

I cannot find how to do a “rundown” test, and I am out of other options. Should I take it apart like you did?

Thanks,

Jake

Did you return your Zumo to the store? Maybe they sold me yours