Greetings,
I am in the process of fixing up an electric scooter. It is powered by a MY1020 500 watt motor. I have dismantled the motor and have noticed that the bearings feel somewhat 'gritty'. While they do still spin freely, they feel as though there is grit inside them. Should I replace them or are they alright?
Also, the bearing at the front of the motor is stuck to the shaft. Can I use one of those devices (with three or four arms) that are used to remove gears from a shaft to remove it or is there a more preferred method?
Thanks,
Sputnik
Clean them. If they have shields or seals than take the one off on the side that will face the inside of the motor. Than flush them with a degreaser or a solvent like gasoline.
If they still feel gritty than replace them. If you have a press than you can press the bearing off the shaft, but otherwise, a puller should work fine.
Replace them with quality name brand bearings from an industrial supplier. They may have a number which is universal for all bearing manufacturers, or the OD, bore, and length can all be measured to find a replacement.
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[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri
I've seen several bearing that are a press-fit. You can track down a machine shop that has the proper tooling to remove/install them, or...
I'd use an angle grinder or dremel to cut it off. for the new bearing, you may be able to cool the shaft in the freezer and heat the bearing for expansion, then pound them together. Just an idea...
Yes, a gear puller will pull a bearing.
NEVER use gasoline for cleaning!! If you must use something from your local gas station, use kerosene.
While we're talking bearings, never spin one with compressed air.
I don't think this is a bearing that can be dismantled
What's the reason for not using petrol? Is it an environmental thing or will it damage parts of the motor?
Sputnik
"While we're talking bearings, never spin one with compressed air."
LOL, sounds like someone has tried this ;).
Grr, now I wanna see one fly apart...
Dunno about the gas. Guess it might eat away at the insulation? But then you just have to make sure you don't get it on the windings. :?
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
The reason for not using gasoline is purely safety. Gasoline evaporates very quickly, the fumes are heavier than air. It makes a "puddle" of vapor around you as you stand there. One tiny spark... static from clothing...drop a wrench and it sparks when hitting the ground... & you are in a fireball. Kerosene on the other hand will not burn without a wick. If you pour a puddle of kero you can not light it with a match. You must put a wick (rag) in it, let that soak up and then light the wick. Simply put, gas is explosive, kero is not. Now don't come back and say "Oh yes, kero will explode"... for sure, if it is vaporized like when an airplane crashed at 550 MPH it can & will, but we're talking standing in your shop cleaning parts. (You did know that jet fuel is kero, right?)
Spinning with compressed air will take the bearing far above rated speed...and you're doing it without lubrication!
That bearing pictured can be disassembled and cleaned, but you ruin the seal in doing so.
Ya know.... 30 yrs ago we cleaned bearings and regreased them, today.... just buy a new one. :)
I haven't used lots of gasoline to clean stuff, just maybe small amounts for spark plugs. In any case, yea, frxdy has a good point. Probably much safer to use kerosene.
I forgot to mention that you need to re-grease the bearings before putting them back in. And if you have to take them off the shaft to clean them than it's probably much better to replace them because the process of pulling them off might do damage. In fact, these bearings are probably so cheap that its better just to replace them because you have the motor open now.
If you have to press or use a hammer to install the new bearings than make sure and apply force to the inner ring. It is also necessary to use something to carry the force than just hitting the bearing. Use a socket or the right size pipe. If you don't have that, than a block of wood can be used. And heat the inner ring before installing, usually if it is heated enough than it will just slide on without any force. Heat to about 200 degrees F, or just not hot enough to burn the grease.
[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri
I have since put the motor back together to keep my room tidy (yes, there are scooter parts EVERYWHERE!). Another concern of mine is when I spin the motor in the 'forward' direction, there's a sort of intermitent clicking noise coming from the brushes. The noise was there before I dismantled the motor only a little less loud and more consistent. Could the brushes just not be seated properly?
Sputnik
It's possible. I would run the motor at low voltage for a few hours in the direction it will be run to wear in the brushes. Did you get them back in the same way as they came out?
[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri