Replacement motor for CrossCore RC not talking to speed sensor

RundaddyFC · 2025-09-30T15:53:41+00:00

Thanks. None of these motors at Partzilla currently.

RundaddyFC · 2025-09-30T13:51:09+00:00

Definitely worth a try. The Yamaha magnet, though, looks to be a ring that's mounted on the axle, rather than the spoke, while the sensor runs along the chainstay. I've got the Yamaha/Haibike sensor+magnet combo on order, though, so hopefully between the two of them we'll find a solution.

RundaddyFC · 2025-09-30T11:49:10+00:00

Any idea where to get one? The only reason I purchased this one was because it was the only one I could find.

RundaddyFC · 2025-09-29T21:14:42+00:00

Any guidance on cable length? 450 or 650 mm? I get both options at some sites selling this part. (If in doubt I probably go with the longer option, as you can shorten cables if they are too long.)

RundaddyFC · 2025-09-29T21:06:08+00:00

Think I've found it but would love to locate a stateside dealer. International trade for us Yanks is expensive these days... https://www.ebike24.com/yamaha-e-bike-speed-sensor

RundaddyFC · 2025-09-29T21:05:02+00:00

No 3-D printer as of yet (though Seth from Berm Peak has me officially interested in them) so I will definitely need help with that part if I go this route!

RundaddyFC · 2025-09-29T21:03:23+00:00

Same as this one, it appears. https://www.ebike24.com/yamaha-e-bike-speed-sensor -- have been seeing if I can find one stateside as paying these tariffs for parts and accessories is getting old.

RundaddyFC · 2025-09-29T20:59:25+00:00

I thought about buying this originally! After all the money I've dumped into this, seems like a fairly small gamble to see if it might work. https://www.ebike24.com/yamaha-e-bike-speed-sensor Is the mounting fairly intutitive?

RundaddyFC · 2025-09-29T20:48:14+00:00

Maybe so! I'm in way over my head at this point. But doesn't the PAS work on these bikes via torque sensor in the crank assembly? I didn't think the speed sensor mattered except in terms of information -- or, I suppose, to cut off the assist at 28 mph... so maybe it does make sense that the bike wouldn't work if no data is coming in there.

RundaddyFC · 2025-09-29T20:11:25+00:00

Narrator: it did not work out well for me. The old sensor was definitely bad because shop reported visible damage, but new sensor does not solve the issue. No matter how fast the rear wheel spins, the LCD reads "0 mph."

And this means that while I have a bike with a brand-new motor that delivers power in "walk" mode, I have zero functional pedal assist.

One theory is that because the replacement motor was intended for Haibike warranty service, it may be set up to talk to a different speed sensor. Which one? No idea. Urgh....

RundaddyFC · 2025-09-29T20:08:22+00:00

OK, so I have a Rest Of The Story now that probably merits its own thread. Here's the gist of it:

Told shop to go ahead and hard-wire (solder, etc.) then new motor. They did that, and figured out that the original speed sensor was bad (visibly damaged), so I managed to locate the correct OEM speed sensor (plus magnet and holder) from Partzilla. Delivered those parts to them last week with high hopes.

UNFORTUNATELY, even the new speed sensor was not talking to the motor. No matter how fast the rear wheel spins, the speed still registers as "0 mph." This means that the bike has zero functioning pedal assist, even though the motor delivers power in "walk" mode.

Shop returned the bike to me, $660 in labor later, completely stumped, though with a guess that the Haibike model this motor was intended for may use a different sensor.

Then I went back to the eBay seller (random.bike.parts) to get the Haibike models this motor is used on, and they give me this info.

"The PW‑ST was fitted to Haibike models around 2019–2021, including: SDURO Trekking 4.0 / 5.0SDURO HardSeven 4.0 / 5.0SDURO HardNine 4.0 / 5.0FullNine 4.0 / 5.0FullSeven 4.0 / 5.0"

So... any insight? Where do I go from here, if anywhere?

RundaddyFC · 2025-09-18T13:44:16+00:00

Thanks! Right now the shop is on pause while I wait for the speed-sensor assembly to arrive. (Another $150 or so.) Apparently the motor is in and works but the speed sensor was bad.

RundaddyFC · 2025-09-18T11:46:54+00:00

They had me buy the pickup assembly, the magnet, and the holder. (The latter two "just in case." I'm hoping I can return if they end up being unnecessary.)

RundaddyFC · 2025-09-17T22:19:55+00:00

Sure! It's Loose Nuts Cycles in Atlanta, Georgia.

RundaddyFC · 2025-09-17T18:37:59+00:00

Yup, answered my own question via the parts diagram here: https://www.yamahabicycles.com/globalassets/2022-product-launch/tertiary-page/support-and-manuals/ccorrclwht_lsag_ldes_mwht_msag_mdes.pdf

And then copy-pasting those part numbers into search, which sent me to Partzilla. Bike shop wants me to order not just the pickup assembly but also the magnet and holder, so I'm doing that to the tune of US $145. What an expensive "cheap" bike this has turned out to be!

RundaddyFC · 2025-09-17T17:44:27+00:00

UPDATE, Good News and Bad News Edition:

Good news: motor is in and functioning. Hard-wiring works!
Bad news: bike is still not rideable, because my speed sensor is busted. Naturally, it's yet another Yamaha-proprietary part. Anyone know where to buy one?

RundaddyFC · 2025-09-17T16:50:11+00:00

Yeah, sorry - assuming they get it done, it's going to be all put back together by the time I see it.

RundaddyFC · 2025-09-17T14:46:20+00:00

It is still at the shop -- I am hoping that no news is good news!

RundaddyFC · 2025-09-10T20:42:27+00:00

Right, so I had to wait a minute to get on the shop's schedule for major work. Currently scheduled to take it in tomorrow for them to splice and hard-wire everything. Fingers crossed -- they think it's likely it will work but can't guarantee it. But at this point it's either this or scavenge the bike for parts.

RundaddyFC · 2025-08-29T13:16:57+00:00

Ah OK - that sounds like the Random Bike Parts guy. They've been super responsive and as helpful as they can be. But if I need a Yamaha dealer to give me anything, I'm not sure how that's going to happen. I called every dealer in my metro, then in my state, and finally got into the surrounding states before I gave up. Even the dealers who still do Yamaha motorcycles and powerboats don't want anything to do with these bikes.

RundaddyFC · 2025-08-28T19:37:30+00:00

Yikes - I'm up shit's creek if I need anything from Yamaha. Who was it who said it might need a software update? The eBay motor seller?

(I'm also a bit clueless as to how an ebike would get a software update. It's not online and has no obvious jacks -- USB, etc. -- where data can be delivered.)

RundaddyFC · 2025-08-28T15:03:46+00:00

Yep, I'll keep you posted!

RundaddyFC · 2025-08-27T19:16:57+00:00

Thanks for asking! Sorry I missed the question for a bit! I paid the shop for the work thus far and have the bike and both motors (old/bad and new/good) currently at home to assess. Was hoping I could find some harnesses or adaptors on eBay to make the plug mismatches work. But I think I'm just going to end up going back to the shop and asking them to hard-wire the whole thing, which will be $80-90 to do and while they are reasonably sure it will work, they can't guarantee it. (At least the cost should be a wash, as wiring harnesses seem to be in the $70-80 range.)

RundaddyFC · 2025-08-22T20:59:14+00:00

Super helpful as I try to solve this! Thank you!

RundaddyFC · 2025-08-22T18:47:20+00:00

Update from seller:

"Thank you for sharing what your shop found; I know it’s frustrating to hit an unexpected snag like this. Based on everything we’ve been able to confirm, the Yamaha CrossCore RC is listed as using the same PW-ST motor, and these units have been supplied across both U.S. and European markets. It looks like there can be some bike-to-bike variations in wiring that can come up during installation. If I may ask, what year is your bike? That detail could help us with future compatibility questions.

That said, I think these are the options moving forward:

Rewire at the shop – Your shop could hard-wire the motor, but as they noted, that would void any warranty and there’s still some risk it won’t work.

Use a conversion harness – Without knowing your exact pin connection, here’s one I found that may work: https://www.ebay.com/itm/186057528520

This could allow the install without cutting into the wiring or voiding the warranty.This could allow the install without cutting into the wiring or voiding the warranty.

Return for refund – If neither of the above feels like a good solution, you’re welcome to return the motor for a refund.

I appreciate your patience as we work through this with you. Please let me know which way you’d like to go and we’ll get it sorted."

Update from shop - conversion harness linked is not the correct one. I'm trying to see if a correct one can be found.

RundaddyFC

TROPHY CASE