Jump to content

My Gotway Monster shell replacement experience


Bob Eisenman

Recommended Posts

It's nice to see that Gotway listened (or maybe just changed their specifications) as they have insulation on the legs of the Hall Sensors to avoid accidental electrical shorts say during vibration or a sudden impact like flying over a hill, catching air, and landing like some people do :whistling:.

Link to comment
Share on other sites

So....the motor cover went back on correctly and turns freely:

https://drive.google.com/file/d/1OGATf_ikc9l0Yk66zkkS6QKfJWM-Ji39/view?usp=drivesdk

The cover, when properly applied, pries the coils away from the magnetically attractive parts and results in a turnable motor axle. When not centered by the cover it is a frozen assembly.

I think I saw the motor interior of another EUC on this forum. I wanted to determine  if the grinding noise it's been making did or didn't produce metallic dust in the motor. The motor looks clean.

https://drive.google.com/file/d/1lKgFxj7LwOHDHvAeCe6hFGx1J6cFtWdX/view?usp=drivesdk

The right side requires the slotted tool approach.

Always fun with to do this stuff with all of you.

Link to comment
Share on other sites

On 10/23/2018 at 4:38 PM, Hunka Hunka Burning Love said:

maybe a O2 sensor socket would work too

Oxygen sensor sockets are 22 mm. Vernier caliper says 24 mm axle nut. Probably worth taking the nut to the vendor and try out the fit hoping for some play in the socket.

 

A guy on Canal St in Salem, MA who runs a repair shop for motor cycles said to look at 'Snap On tools'. A 15/16 inch (24 mm) pm - particulate matter sensor socket with a 1/2 inch drive can be purchased.

https://store.snapon.com/Sensor-and-Filter-Sockets-1-2-Drive-SAE-15-16-Sensor-Socket-P891694.aspx

It looks just about right in terms of slot size.

$43.75

I think I'll wait a bit.

Link to comment
Share on other sites

11 hours ago, Bob Eisenman said:

Oxygen sensor sockets are 22 mm. Vernier caliper says 24 mm axle nut. Probably worth taking the nut to the vendor and try out the fit hoping for some play in the socket.

 

A guy on Canal St in Salem, MA who runs a repair shop for motor cycles said to look at 'Snap On tools'. A 15/16 inch (24 mm) pm - particulate matter sensor socket with a 1/2 inch drive can be purchased.

https://store.snapon.com/Sensor-and-Filter-Sockets-1-2-Drive-SAE-15-16-Sensor-Socket-P891694.aspx

It looks just about right in terms of slot size.

$43.75

I think I'll wait a bit.

Have you tried Autozone or other auto parts stores?  They loan tools for free,  just leave a deposit.  Might get lucky and find one with a 24mm socket.

Link to comment
Share on other sites

1 minute ago, Bob Eisenman said:

I made a socket tool to remove the right side axle nut.

Angle grinding the 24 mm socket for use in the Monster's axle nut

Time to return the 4 hour rental of the angle grinder. 

Thanks @Rehab1 for the tool slotting plan! 

 

Love the "can do" attitude, and great picture :thumbup:

Link to comment
Share on other sites

1 hour ago, Bob Eisenman said:

I made a socket tool to remove the right side axle nut.

Right side axle nut offSlotted 24 mm socket and the Monster axle nutAngle grinding the 24 mm socket for use in the Monster's axle nut

Time to return the 4 hour rental of the angle grinder. 

Thanks @Rehab1 for the tool slotting plan! 

 

Look at you Bob and you still have all of your fingers.:thumbup: Glad you donned gloves. Your task was much harder than my method. Congrats!

Link to comment
Share on other sites

Gotway Monster shims:

While the shims were out on the left side of the Monster I measured them and made a shop sketch.

They have unexpected bevels in unexpected places.

Gotway Monster shims

Simply tightening the nut eliminated the 'rocking' of the pedal column. The shims did not lay flat in the pedal column enclosure but tightened down with an authoritative firmness. Perhaps they will loosen up again. If the 'simply tighten' approach holds up then the shells possibly will not need to be removed to occasionally tighten up the pedal column looseness.

Link to comment
Share on other sites

1 minute ago, Bob Eisenman said:

Gotway Monster shims:

While the shims were out on the left side of the Monster I measured them and made a shop sketch.

They have unexpected bevels in unexpected places.

 

Simply tightening the nut eliminated the 'rocking' of the pedal column. The shims did not lay flat in the pedal column enclosure but tightened down with an authoritative firmness. Perhaps they will loosen up again. If the 'simply tighten' approach holds up then the shells possibly will not need to be removed to occasionally tighten up the pedal column looseness.

Yes, if the shims are not distorted and need replacing, simply tightened the nuts can be enough.

Link to comment
Share on other sites

20 minutes ago, Rehab1 said:

Your task

I haven't had this much fun since I built a set of stairs for my mother's house, after she passed.

In shop class in about 8th grade in Connecticut (1960s) I turned a piece of laminated wood on a lathe into a ' Bongo board's which sits in the closet.

https://goo.gl/images/D7uMv4

I found this YouTube video worth watching as far as angle grinding goes

 

Link to comment
Share on other sites

 

59 minutes ago, Rehab1 said:

Look at you Bob and you still have all of your fingers.

Yes...the first few cuts went a little too low in the socket. You make a much more skilled looking slotted socket to than me. Lining up on the points of the 6 point socket was a good guide for first cuts. The tool was much more adaptable to finishing out the loose cut socket metal than I expected.

The guy in town who runs a motorcycle repair shop felt uneasy about the idea of weakening a socket by milling a slot. 

The tool seems to be quite strong despite the removal if a hex nut face.

24 mm socket after angle grinding - deburred with a hand file

 

Link to comment
Share on other sites

It's back together again...Monster is sooo...much heavier than the Ninbot One E+ I've been riding to The Home Depot.

Bent axle may be only slight. No shims required to reassemble the shells onto the pedal columns. Tightening the axle nut onto the shims has improved the geometry towards normal.

Test ride will tell.

3 hours ago, meepmeepmayer said:

You're making your own shims? Respect!

Ha ha...!

I was in the mood to make a sketch.

Monster shim tinkering finished

 

Monster shim tinkering finished

 

.

Link to comment
Share on other sites

On 10/16/2018 at 2:41 AM, Hunka Hunka Burning Love said:

You can get Kafuter 704 RTV white silicone sealant on eBay for cheap. 

The adhesive arrived today from China.

However my effort to tighten the axle nuts to eliminate pedal column shift and to hopefully rid the Monster if a recent grinding noise proved catastrophic.

The reassembled Monster had severe grinding noise and when 'unpowered' was not able to rotate it's wheel freely.

Disassembly shows that the right pedal column and left are not interconnected.

https://drive.google.com/file/d/1s7DwhLwbbqHN6K1k-9hS5Mw0KCV0nj3W/view?usp=drivesdk

Some sort of broken axle (or interior axle weld point) I'd guess.

A quick look at Facebook's 'fix my wheel electric unicycle' (Joey Serrin - administrator) found no cases of Monster EUC with broken axle.

Replacement motor runs about $750 on eBay. Jason at eWheels contacted me about shims being available in a recent shipment but given the axle issue I declined a previous interest in buying shims.

 

Link to comment
Share on other sites

20 minutes ago, Bob Eisenman said:

The adhesive arrived today from China.

However my effort to tighten the axle nuts to eliminate pedal column shift and to hopefully rid the Monster if a recent grinding noise proved catastrophic.

The reassembled Monster had severe grinding noise and when 'unpowered' was not able to rotate it's wheel freely.

Disassembly shows that the right pedal column and left are not interconnected.

https://drive.google.com/file/d/1s7DwhLwbbqHN6K1k-9hS5Mw0KCV0nj3W/view?usp=drivesdk

Some sort of broken axle (or interior axle weld point) I'd guess.

A quick look at Facebook's 'fix my wheel electric unicycle' (Joey Serrin - administrator) found no cases of Monster EUC with broken axle.

Replacement motor runs about $750 on eBay. Jason at eWheels contacted me about shims being available in a recent shipment but given the axle issue I declined a previous interest in buying shims.

 

:crying: Oh man, that's too bad. I know how you must be feeling right now.

Did you buy your Monster from EWheels? Given how much ACM motors cost I find it hard to believe that a Monster motor would cost $750. Also check Speedy feet. I bought a ACM motor from Ian for ~$250 and shipping wasn't that much.

Link to comment
Share on other sites

37 minutes ago, Marty Backe said:

I find it hard to believe that a Monster motor would cost $750

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F253949172105

The seller prices ACM2 motors at about $450.

One or both of the batteries has a bad cell(s) since it only charges to 78%. It was not an eWheels purchase.

Sort of an expensive problem no matter what is done. 

As an alternative thought Gotway MSX with no batteries (same type as Monster) can be purchased for about $1400 and the 19" wheel probably gets better mileage and weighs less.

 

 

Link to comment
Share on other sites

10 minutes ago, Bob Eisenman said:

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F253949172105

The seller prices ACM2 motors at about $450.

One or both of the batteries has a bad cell(s) since it only charges to 78%. It was not an eWheels purchase.

Sort of an expensive problem no matter what is done. 

As an alternative thought Gotway MSX with no batteries (same type as Monster) can be purchased for about $1400 and the 19" wheel probably gets better mileage and weighs less.

Those are inflated prices IMO. Do send an e-mail to Speedyfeet. What you do have to lose?

Yet with your battery issues, maybe this is an omen, telling you that it's time for a new wheel. You certainly got some good use out of your Monster.

I do think that the Monster fits you better, and there's nothing like a 2400wh battery pack :)

Link to comment
Share on other sites

12 minutes ago, Marty Backe said:

send an e-mail to Speedyfeet.

Yeah ... I did send him an email.

12 minutes ago, Marty Backe said:

there's nothing like a 2400wh battery pack 

My Monster is the 1600 WHr variety.

eWheels sells the 800 WHr packs for $575.

The mosfet(s) still look good and the case shells are newly purchased.

Pedal columns look ok.

Link to comment
Share on other sites

Are you 100% certain the axle is broken?  :blink:  It’s a solid piece of metal with a hollow channel on one side.  And how could cranking on a nut twist the axle enough to break?  Maybe double check the orientation of the shims and check to see how they are sitting.  I think the flats on the axle need to match the shims slots?  Do you have some photos or video of how you assembled the pedal supports/shim/axle?  It almost seems like maybe the shims aren’t locking correctly?  When you rotate the pedal support can you see if the axle / nut is turning with it?

I’d take the supports off again and verify by locking a vice grip on and spinning the axle.  When taking a motor cover off, it might be best to mark some alignment lines on the cover and rim so you can place it back on in the same orientation.  Maybe the cover is misaligned.  Did you take just one side off?  It’s best to remove only one at a time I think to help maintain the magnet/stator microgap.  Never remove the cover unless you really need to.  Why did you take the cover off?

Just in case anyone is curious, this video shows pretty well how the shims work on a Ninebot One.

 

Link to comment
Share on other sites

48 minutes ago, Bob Eisenman said:

Yeah ... I did send him an email.

My Monster is the 1600 WHr variety.

eWheels sells the 800 WHr packs for $575.

The mosfet(s) still look good and the case shells are newly purchased.

Pedal columns look ok.

Ah, I must have forgotten that you only had the small Monster. Just remember, no wheel cruises quite like the Monster, with that 22-inch wheel.

But anyway, you're in a tough spot unless you can get a motor for a more reasonable price.

Link to comment
Share on other sites

1 hour ago, meepmeepmayer said:

Even on AliExpress

Cool...I forgot about that price on AliExpress when viewed as an add to cart choice

https://m.aliexpress.com/item/32831474848.html?pid=808_0000_0101&spm=a2g0n.search-amp.list.32831474848&aff_trace_key=&aff_platform=msite&m_page_id=6581amp-OxboIEs_LKtviwvS2BsqCQ1540876408593

 

Link to comment
Share on other sites

  • 3 weeks later...

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...