Saris H3 Knock and Overheat?

I purchased the H3 via REI and their 20% off.

Exchanged for another when the power connector crapped out. I shipped the replacement to the store but due to CV19 they would not take the bad one (PS only issue) back so I now have two.

Both exhibit the “knocking” issue that i have come across online. If I pedal smoothly it disappears but uneven pedaling due to increased watts draw it comes around. Verified it is not pedals, cleats, or crank. Any new ideas on this?

Second issue has happened once. Doing Zwift and doing the main Mountain loop with the climb to the tower. I ride in the garage and it was ~90 F (big fan on me) and I did ~200 watts on the main climb. For pitch up to the tower I have to stand and I was doing ~250 watts. About 2/3 of the way the resistance suddenly gave way and max wattage was ~180 no matter what gearing. After a couple of minutes the resistance came back but soon cut out for the rest of the climb. Partway down the resistance came back (hit 900 watts on little rise 1/3 of the way down). I assume this issue is overheating protection but wanted to make sure.

Any ideas on either of these issues? Really other than the knocking and cheap connector cable I really like the units.

I have had ZERO response from Saris despite multiple emails. I am very tempted to return and replace with a Kickr or Kickr Core.

Any ideas appreciated. Thanks, chris


We purchased 2 trainers in January from REI and had a problem with one.
I contacted Saris and sent video. It was making a clicking noise and they responded well but their theory was the belt needed adjustment. I did not have the correct tools for the job and needed a longer Allen wrench to access the cover screws. In addition one was already rounded from their assembly and I could not get it out. They should have included the correct wrench to access the cover screws and should have also used cap head style instead of the shallow ones that strip easily. If I have to remove the cover screws I will try to find some deeper head cap screws and replace the ones I take out for future service. I exchanged thru REI and shipped the defective one back to REI in the new box from my work location. If I were you I would return it and get the other brand. I was slightly disappointed with their response but have had great service from them (Saris) in the past. I was hoping since this trainer had been out for a while there would be no problems and the reviews were good. I hope the 2 we purchased last us and if they do not I will opt for the other brand.

That happens to me about 4 times a year with my H2. I think it’s Zwift because it’s most likely to happen in the same part of Watopia. Regardless, it’s not thermal protection… it’s happened to me warning up under 200W and we’re not going to stress this trainer at 250W plus 90F ambient isn’t that hot.

I have an REI store nearby so easy to drop off and get another…although the reason I have two is that they would not take the return at the time. Got a lead on the knocking and one issue is loose adapters and one of the units I have had this. So will be checking it out. Thanks for your feedback.

@D_Green \mm
Thanks for your feedback. One note I left out was when the ride was over I touched the H3 and it was extremely warm/hot. About a 2 second touch. Much hotter than my Snap ever got.

I am not doing any big climbs anytime soon…100+ for the next week…but will be watching out for this. I need to take the trainer inside but not sure my wife would allow the big, loud fan!

Check your H3 firmware!

There was a update recently.

Oh, maybe you do have an issue there. I’ve never noted my H2 being anything more than very warm after, say, Alpe du Zwift… certainly not hot.

You could try the firmware update mentioned above.

Firmware is up to date (I updated a couple of weeks ago)
Non-drive side spacer was loose so tightened it down

Knocking is better but still exists; primarily when the effort is lessoned: say going from a 200-250 watt effort and then easing into 100-120 watt…as the H3 ramps down with no resistance on the pedals the knocking occurs. Note I do not hear a knocking (earphones on) but feel it in the pedals. It rotates between left/right pedals at different times so not a pedal/crankarm issue and the bottom bracket feels tight but admittedly has not been serviced in a few years. I need to check my other H3 which had both spacers loose.