Problem with a Cytronex conversation

[Hamsphire John]

I fitted a Cytronex kit to my Decathlon Network 700 about a year ago. All has gone well but for one fairly minor issue. Recently I have a rubbing sound coming from the motor. It appear to go quiet when I stop asking it for electrical assistance. The sound is rhythmical not random, a light metallic scraping. Anyone got any ideas?

 

[Bikes4two]

Can't help you on that but I'd be pleased to hear what Cytronex customer service say / offer to do to help.

In the past, Cytronex CS haven't exactly shone - maybe there's been an improvement?

 

[Benjahmin]

Check the main power connections to the motor. I know it sounds mechanical but if one phase is resistive it can cause all sorts of horrible noises.
Look for signs of heat damage at the connectors, swollen or burnt insulation.
Had this on my Ezee conversion, stripped the motor twice 'cos I was convinced it was mechanical. Turned out to be the bullet connector at the motor, burnt/corroded. Replaced them with a decent power connector (3 way connector, someone will know the name) and no problems since.

 

[Hamsphire John]

Check the main power connections to the motor. I know it sounds mechanical but if one phase is resistive it can cause all sorts of horrible noises.
Look for signs of heat damage at the connectors, swollen or burnt insulation.
Had this on my Ezee conversion, stripped the motor twice 'cos I was convinced it was mechanical. Turned out to be the bullet connector at the motor, burnt/corroded. Replaced them with a decent power connector (3 way connector, someone will know the name) and no problems since.

Thanks very much Benjahmin. I pulled the electrical connector which leads to he motor. At first I was worried that I wouldn’t get back the right way. Then the 3 phase throry which I studied some 45yrs ago returned! All three pins seemed clean. The ‘female’ end of the connector goes to the battery/control unit via the bottle mounting unit. If that latter is okay then I hope I shouldn’t have electrical issues?

 

[Bikes4two]

Have you contacted Cytronex Customer Services for advice yet? It might be a common problem easily resolved?

I don't particularly follow postings about Cytronic kit as much as I might, but iirc I've seen postings of folks having connection problems of some sort that resulted in a 2nd generation/redesign of the piece involved. That's all very vague I know, but it goes to show that a call to CS may be all revealing.

Here's some links that may whet your appetite to more in-depth searches on problems others have experienced (but to be fair, a lot of people love them and don't seems to have issues).

https://forum.cyclinguk.org/viewtopic.php?t=150254

Cost of Cytronex Repair - Cycling UK Forum

Pro’s and cons of buying Cytronex

Having had out KTM MACINA s stolen, I am considering replacing them with Cannondale/Cytronex, in the full knowledge that better priced and better specced donor bikes are available elsewhere, Even Decathlon B’Twin. Lightness, plus excellent Dec 2017 forensic review in A2B mag. are very...

www.pedelecs.co.uk

Help! - Cytronex Cannondale Quick 6 Problems

My partner purchased a second hand Cytronex Cannondale about four months ago. On it's first outing it broke down and a call to the previous owner had it quickly fixed, by twiddling the reed switch in it's holder under the rear brake lever. Not ideal and it happened a few more times in...

www.pedelecs.co.uk

 

[Hamsphire John]

Thanks Bikes4two. My previous contact with Cytronex after care wasn’t particularly fruitful. They said book an appointment for my bike and we charge you £32 per half hour. I declined the offer!

 

[saneagle]

Thanks Bikes4two. My previous contact with Cytronex after care wasn’t particularly fruitful. They said book an appointment for my bike and we charge you £32 per half hour. I declined the offer!

There has been a lot of discussion on this forum about Cytronex kits. If only you had read them before choosing it because your sort of problem is mentioned. Basically, these type of kits are great until they go wrong, then you have very limited options for sorting them out.

OK, we can't change the past but we can learn from it to improve the future. Let's start with the problem. Assuming their C1 kit, the motoris an Aikema 85 100. You mentioned three wires only, which means it's sensorless. Sensorlesss motors give the controller a much harder time than sensored ones, so the chance of MOSFET failure is high. The syptoms you decribe are consistent with a degraded MOSFET, though that doesn't necessarily mean it's the cause. You can get the same from a bad connection anywhere between the motor and controller. Motor problems are extremely rare, but not unheard of. If it were a sensored motor, I'd say you have water in it. Water doesn't affect sensorless motors electrically, but the corrosion can still cause it to make noises like you describe, though I'd expect the noise at all speeds and powers in that case, and when those motors get corroded, the clutch tends to go first.

First you need to confirm that it's a sensorless motor (only 3 pins in the connector), then you should do a MOSFET test for their resistance. Any significant imbalance would indicate a problem. Search this or other ebilke forums for how to do that test. You can test through the pins on the motor connector controller side.

If you find any problem with the controller, it would probably be best to replace the entire electrical system other than motor and battery, and replace with standard Chinese one, and pray that you can hack into the battery, otherwise get a cheap Chinese bottle battery from Aliexpress. The present controller is integrated into the battery and sold asa spare part for £500, which is more than a whole equivalent kit of the same quality from a Chinese seller, and you get much more flexibility, cheap spares and availability of spares with the Chinese kit.

 

[Hamsphire John]

Bikes4two, it hopefully appears that I *might* of solved. I undid the front wheel nut which carries the power cable to the motor. I made sure that the cable was in the slot in the nut and tightened it up again. I've ridden back from town some 2 miles with a nasty up hill bit at the end and heard no light scraping sound as before. I could have strained the cable causing a poor connection to one phase? It's early days but all available digits are crossed!

 

[JakeCy]

Hi John. If you're issue has been solved - great! However, motor noises can stem from reasons with your bike and not solely the electronics. If you find any noises return, please send us a log from your bottle and use the contact form on our website to let us know you have an issue. You're local to us so we'd be happy to diagnose the issue in the workshop for you and get solve any issues you've got.

Thanks
Jake