Gearbox protection
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- Oyabun
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Gearbox protection
As I was not satisfied with the level of protection of the gearbox, I have drilled the gearbox oil drain screw and glued in a small special neodymium magnet.
Special in a sense that normal N type neodymium magnets have relatively low working temperature (65 to 85C) above which they start to lose their magnetic abilities and eventually demagnetize.
The installed tiny magnet is 6mm long and has 4 mm diameter is an SH type - which has a higher working temperature of 150C.
Not sure it will ever get to that point in the gearbox, but I wanted to stay safe.
I have already done this on my 2013 model a year ago, and still find some metal chippings in the gearbox oil - as the gears are turning on each other.
I hope this will protect the gearbox from having the hassle of changing a main shaft bearing again which was a major PITA I have to say.
Special in a sense that normal N type neodymium magnets have relatively low working temperature (65 to 85C) above which they start to lose their magnetic abilities and eventually demagnetize.
The installed tiny magnet is 6mm long and has 4 mm diameter is an SH type - which has a higher working temperature of 150C.
Not sure it will ever get to that point in the gearbox, but I wanted to stay safe.
I have already done this on my 2013 model a year ago, and still find some metal chippings in the gearbox oil - as the gears are turning on each other.
I hope this will protect the gearbox from having the hassle of changing a main shaft bearing again which was a major PITA I have to say.
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Re: Gearbox protection
Good tip. Where can you source the magnets from and what glue did you use?
- Oyabun
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Re: Gearbox protection
I have purchased the magnets at a speciality shop locally two years ago when I done it for my 13 model. They are doing a lot of industry applications and have some research background also. -Actually they have advised me on the temperature limitations of neodymium magnets, and helped me on selecting installation size too. Originally I wanted larger magnets, but they explained that with this proportions the magnetic flux can close back to the sides of the steel bolt therefore effectively giving a larger surface area with better filtering capability.
I used epoxy last time - but as the application needs a very tiny drop only I just didn't feel to donit this time. I tried high strength thread lock as it was at hand, polimerizes under the pressure what the magnet exterts to the steel bolt, neutral to oils and was thin enough that I could insert the 4mm magnet to a 4.2mm mm hole. Let it fully cure overnight and it did not move at all so I decided it will be fine.
Hope it helps.
I used epoxy last time - but as the application needs a very tiny drop only I just didn't feel to donit this time. I tried high strength thread lock as it was at hand, polimerizes under the pressure what the magnet exterts to the steel bolt, neutral to oils and was thin enough that I could insert the 4mm magnet to a 4.2mm mm hole. Let it fully cure overnight and it did not move at all so I decided it will be fine.
Hope it helps.
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Re: Gearbox protection
Oyabun wrote:I have purchased the magnets at a speciality shop locally two years ago when I done it for my 13 model. They are doing a lot of industry applications and have some research background also. -Actually they have advised me on the temperature limitations of neodymium magnets, and helped me on selecting installation size too. Originally I wanted larger magnets, but they explained that with this proportions the magnetic flux can close back to the sides of the steel bolt therefore effectively giving a larger surface area with better filtering capability.
I used epoxy last time - but as the application needs a very tiny drop only I just didn't feel to donit this time. I tried high strength thread lock as it was at hand, polimerizes under the pressure what the magnet exterts to the steel bolt, neutral to oils and was thin enough that I could insert the 4mm magnet to a 4.2mm mm hole. Let it fully cure overnight and it did not move at all so I decided it will be fine.
Hope it helps.
It does, thanks
- Mel46
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Re: Gearbox protection
I am not a mechanic by a long shot so I am a little confused. Are the shavings that are collected so small that they come out when you pull the magnet? I know that when I drain the oil on mine I can not see if anything might be too large to get through the hole, and there isn't really a filter...just a screen that is on the side, not the bottom, which means that it may not get all of the metal shavings. I know that this is a scooter and not a high temp motorcycle, but I think the oil filter is lacking on the PCX. This may be the best alternative that I have seen.
Currently own:
Red 2013 Honda PCX150
Givi tall windshield & tailbox - Lots of extra lights
Custom seat from Thailand - Bad Boy Airhorn
Takegawa Lowering Shocks - Michelin City Grip Tires
Headlight assy upgraded to LEDs w/HS5 main bulbs
NCY variator, drive face, and rollers
Red 2013 Honda PCX150
Givi tall windshield & tailbox - Lots of extra lights
Custom seat from Thailand - Bad Boy Airhorn
Takegawa Lowering Shocks - Michelin City Grip Tires
Headlight assy upgraded to LEDs w/HS5 main bulbs
NCY variator, drive face, and rollers
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Re: Gearbox protection
Thanks Mel,Mel46 wrote:I am not a mechanic by a long shot so I am a little confused. Are the shavings that are collected so small that they come out when you pull the magnet? I know that when I drain the oil on mine I can not see if anything might be too large to get through the hole, and there isn't really a filter...just a screen that is on the side, not the bottom, which means that it may not get all of the metal shavings. I know that this is a scooter and not a high temp motorcycle, but I think the oil filter is lacking on the PCX. This may be the best alternative that I have seen.
To ease the confusion the Gearbox and the engine have separate oil circuits. The gearbox has not even a filter - just a filling and drain bolt. It contains 0.16-0.18 liters of oil and the gears and bearings are oiled by the same fluid. The particles are minuscule filings or chippings are coming from the gears running on each other and wear out. I've checked the transmission oil every time before the installation in a way that I have placed a magnet below the plastic container used to capture the drained oil and found that quite a lot of the small dark particles were reacting to it. i'm suspecting that these fine metal particles suspended in oil can cause the early death of the bearings (especially the input shaft which has a great torsion load from the variator) thus I made this.
I'm installing a magnet to the engine oil drain plug also, but those available ready made relatively cheap so one can pick them up in a motorcycle related store for a few bucks anytime - whilst I haven't seen any solution for the gearbox so far.
- Alibally
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Re: Gearbox protection
Some manual gearboxes on cars have a magnet on the drain plug and you would be surprised how much metal it collects. It should just be like fine filings though. Any big chunks is a no no.
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Re: Gearbox protection
Across forums, does anyone know of reports of final drive failing on '13-15 pcx's? Just wondering if this is a problem or not?
To my knowledge the outstanding failings that Honda know of but do not seem to fix on new sales are clutch bearing and steering bearings (even new Forza 125's have had similar failings - so Honda not sorted yet).
To my knowledge the outstanding failings that Honda know of but do not seem to fix on new sales are clutch bearing and steering bearings (even new Forza 125's have had similar failings - so Honda not sorted yet).

- Oyabun
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Re: Gearbox protection
Not a specific issue like the clutch bearings, but if I'm not mistaken pcxdemon had complained about his final reduction bearings a while ago.iceman wrote:Across forums, does anyone know of reports of final drive failing on '13-15 pcx's? Just wondering if this is a problem or not?
To my knowledge the outstanding failings that Honda know of but do not seem to fix on new sales are clutch bearing and steering bearings (even new Forza 125's have had similar failings - so Honda not sorted yet).
- Mel46
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Re: Gearbox protection
I've never changed the gearbox oil in either of our PCX 150s. How often does it need changing? Mine has around 5,000 miles on it while my wife's bike has around 13,000. Her bearing went out at 10,ooooh so they may have changed it then. Not sure though.
Currently own:
Red 2013 Honda PCX150
Givi tall windshield & tailbox - Lots of extra lights
Custom seat from Thailand - Bad Boy Airhorn
Takegawa Lowering Shocks - Michelin City Grip Tires
Headlight assy upgraded to LEDs w/HS5 main bulbs
NCY variator, drive face, and rollers
Red 2013 Honda PCX150
Givi tall windshield & tailbox - Lots of extra lights
Custom seat from Thailand - Bad Boy Airhorn
Takegawa Lowering Shocks - Michelin City Grip Tires
Headlight assy upgraded to LEDs w/HS5 main bulbs
NCY variator, drive face, and rollers
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Re: Gearbox protection
Maybe that's why it failed Mel. I changed the oil early on the PCXs (and you know how set against that I am). And the swarf was really obvious on one of them.Mel46 wrote:I've never changed the gearbox oil in either of our PCX 150s. How often does it need changing? Mine has around 5,000 miles on it while my wife's bike has around 13,000. Her bearing went out at 10,ooooh so they may have changed it then. Not sure though.
The other was ok.
So I guess you take yer chances.
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Re: Gearbox protection
As per the service schedule the final drive oil should be changed every two years. In case they changed any of the gearbox bearings (and not the clutch as it is not oiled) the transmission oil is surely changed in her bike. However I'd suggest to do it on your bike if it has never been done. it is very easy to do, the how-to is here: http://hondapcx.org/viewtopic.php?f=3&t=3224Mel46 wrote:I've never changed the gearbox oil in either of our PCX 150s. How often does it need changing? Mine has around 5,000 miles on it while my wife's bike has around 13,000. Her bearing went out at 10,ooooh so they may have changed it then. Not sure though.
I tend to do it every second time I change engine oil by using the remaining fresh stuff left in the liter can. As I was riding about 12k kms last year it happened that I had three engine oil changes and two gearbox ones (one complete when I have bought t used, one engine oil change mid-year after 8k km, and one complete before winter).