Gearbox bearing fun

31 replies [Last post]
ofx210p
Offline
Joined: 10/20/2008
Points: 375

Couple of things really.

Today I took my gearbox apart again because its whine has gotten quite bad. Admittedly it has 27,000km on the clock, so thought i'd investigate more as simply changing the oil didnt make any difference.

What I found was that the main bearing at the back of the gearbox was basically stuffed and there was movement to load up the gears significantly to make them whine a lot louder than my previous machine.

The short term answer for me was to swap the gearboxes over. Which i did. I also took the bearings to a bearing co to get matched up and they believe them to be chinese bearings simply because they have no markings on them whatsoever.

I've ordered a new bearing for it

vectrix gearbox bearing.jpg

You can see the bearing at the back of this photo.

Anyhow the cost difference between Chinese and Japanese bearings. Chinese bearing $35 NZD Japanese Bearing $90 NZD

The bearing fit also isnt particularly tight and I was told by the engineering co. (next to the bearing co.) that they'd used bearing locktite on it. Getting it out was as simple as a few well placed taps with a hammer and a well fitting chunk of metal. NOTE : there is a fairly well hidden circlip/retaining ring stopping the bearing falling out. Obviously remove this prior to replacing.

So, if you take the side of the swing arm off and unbolting the large nut as if to remove the back wheel and then, grab the tyre and see if there is any movement. If there is - the bearing on the back is toast.

When the bearing arrives (next week or so...) i'll post all the size details and what not of the bearings and the seals req.

Next thing was that i noticed is that the front brake caliper and the back brake calipers are identical including the mount. Not that this helps anyone but i thought it interesting.

See here
Right hand is Rear, Left hand is a front

calipers.jpg

Thats about it for the day....

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
R
R's picture
Offline
Joined: 06/18/2009
Points: 1398
Re: Gearbox bearing fun

Next thing was that i noticed is that the front brake caliper and the back brake calipers are identical including the mount. Not that this helps anyone but i thought it interesting.

It helped many user to swap brakes. Right hand brakes rear wheel (regen and disc brakes), left hand brakes front wheel, this configuration is safer than the classic)

martinwinlow
Offline
Joined: 03/26/2012
Points: 202
Re: Gearbox bearing fun

Hi,

"...grab the tyre and see if there is any movement." I assume you mean perpendicular to the wheel axle...? It would be interesting to see if there is any similar movement with the new bearing in.

Have you explored replacing/modifying the planetary/sun/ring gears as I gather they were not of wonderful quality when new and hence the usual V racket...? MW

__________________

Regards, Martin Winlow
Herts UK
evalbum.com/2092

MEroller
MEroller's picture
Offline
Joined: 09/26/2011
Points: 653
Re: Gearbox bearing fun

R wrote:

Right hand brakes rear wheel (regen and disc brakes), left hand brakes front wheel, this configuration is safer than the classic)

What makes swapping the hand brakes from the universally accepted right=>front and (for scooters with variomatic or without transmission) left=>rear configuration to the other way round safer? For me at least this would quickly spell disaster, as any emergency braking is instinctively full-pull for the right hand and only hard pull for the left. I gather Vectrix did this strange and in my eyes dangerous swap on the VX1 - for what reason? Out of fear that the patented regen throttle grip on the right would catch a Vectrix biker off guard when emergency braking suddenly became necessary?

__________________

My (former...) ride: E-Sprit Fury (basis is the ZAP/Erider Thunder 5000) since May 03, 2011. Mods: Battery temp. gauge and battery heating (off the grid and off the battery), Kelly KEB72801X, reverse activated, luggage rack with topcase, HC Cycle Analyst, Emsiso BMS2405, 35mm² battery cables, now wrecked

Mik
Mik's picture
Offline
Joined: 12/11/2007
Points: 3726
Re: Gearbox bearing fun

MEroller wrote:
R wrote:

Right hand brakes rear wheel (regen and disc brakes), left hand brakes front wheel, this configuration is safer than the classic)

What makes swapping the hand brakes from the universally accepted right=>front and (for scooters with variomatic or without transmission) left=>rear configuration to the other way round safer? For me at least this would quickly spell disaster, as any emergency braking is instinctively full-pull for the right hand and only hard pull for the left. I gather Vectrix did this strange and in my eyes dangerous swap on the VX1 - for what reason? Out of fear that the patented regen throttle grip on the right would catch a Vectrix biker off guard when emergency braking suddenly became necessary?

That's an important question and has been debated many times and there is nothing wrong with bringing it up again.
I would however like to suggest that you start a new thread about it, so that this one can stay on topic for the gear box bearing details. It is shaping up to be a very interesting and useful thread and I have added it to the Collaborative Handbook. So please stay on topic :-)

__________________

This information may be used entirely at your own risk.

There is always a way if there is no other way!

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

ok in answer to the question about when the replacement bearing is in there and grabbing the wheel and pulling perpendicular to the bike. After fitting the replacement other gearbox, all the play has now gone and i checked whilst dismantling this one as to what was creating the play.

In answer to modifying the current gear set. I don't believe either set that i have are particularly good. Although i have taken the main whine out of this by fitting another box. The gears still feel kinda nasty under load.

As for the brakes... the point i was trying to make (and not bringing up the reversing brake levers debate again) was just that both rear and front calipers and mounts are identical and interchangable. Nothing more really.

kingcharles
kingcharles's picture
Offline
Joined: 08/17/2009
Points: 400
Re: Gearbox bearing fun

Have you also checked the motor mounting bolts? I can remember that they snapped off from somebodies bike recently (was it Turok?)
Did you feel the bike handling differently with the play on the rear wheel? I can imagine that steering into a corner you might feel it "set" itself.
Thanks

__________________

Once you go EV, Gas is history!

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

Yes Kingcharles, you have to undo those bolts in order to check all this properly, however before i undid them i checked their tightness and they were all tight.

What i found cornering was a rough feeling on each corner as the gears were loaded and if i remember correctly you couldn't 'feel' the movement into the corner but the roughness of the bearing and gears was evident.

Cheers

Chris

Anderson
Offline
Joined: 10/11/2008
Points: 134
Re: Gearbox bearing fun

One thing not discussed is the internal clearance specification ( usually C2 - C5 ) of the wheel bearing. On my Vectrix I would guess it's a C4 or C5 because there's noticeable wheel movement perpendicular to the axle and since it has only has 40 miles on it, it couldn't be wear.

If the new bearing your getting is less then C4 I might wait before installing it until I could somehow find out what the Vectrix bearing spec is.

More on internal clearance for ball bearings;
http://www.ntn.ca/faq.htm#c3fit
http://www.dynaroll.com/radial-axial-play.asp

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

Another question on this front before i tear into it again.

When i pulled my gearbox apart, i noticed that the bigger bearings are open and lubricated by the gearbox oil however each of the planetary gears have needle roller bearings which (from the channel behind them) look as if they too are lubricated by the motion of oil. But from inspection they look like they are actually greased with what looks like a white grease.

Now obviously oil and moisture can turn into a mayonase type structure where oil becomes white. However i'd like to get definitive data on this if it is white lithium grease or somesuch as this also appears to be the case on the swingarm bearing too. XVECTRIX anyone ?

It would make me happiest not to have to rebuild this gearbox after the 3rd time and to ensure it goes reliably.

Incidentally the replacement main bearing from japan is sealed and not open like the original.

MEroller
MEroller's picture
Offline
Joined: 09/26/2011
Points: 653
Re: Gearbox bearing fun

I would be inclined to think (from an engineering standpoint) that in an environment with unfiltered gearbox lubrication oil needle and ball bearings will survive longer when sealed and filled with a ball bearing grease. As the Vectrix gearbox seems to use the oil to bind worn-off particles these particles will cause increased wear in open bearings. And such oil usually turns pitch-black. So what you saw in the needle bearings may in great likelyhood be some kind of grease. As you worte these were the bearings of the planetary gears they would not be lubricated well by the oil sploshing around the gearbox, which will keep to the outer circumfrence and thus mainly lubricate the gear teeth, with only oil mist reaching the planetary gear bearings.

__________________

My (former...) ride: E-Sprit Fury (basis is the ZAP/Erider Thunder 5000) since May 03, 2011. Mods: Battery temp. gauge and battery heating (off the grid and off the battery), Kelly KEB72801X, reverse activated, luggage rack with topcase, HC Cycle Analyst, Emsiso BMS2405, 35mm² battery cables, now wrecked

Mik
Mik's picture
Offline
Joined: 12/11/2007
Points: 3726
Re: Gearbox bearing fun

Excuse my ignorance, but would grease not be washed away by oil until there is either a uniform mixture everywhere in the gear box or until there is no liquid oil left to slosh around?

__________________

This information may be used entirely at your own risk.

There is always a way if there is no other way!

MEroller
MEroller's picture
Offline
Joined: 09/26/2011
Points: 653
Re: Gearbox bearing fun

As long as there is oil FLOW, and the grease and oil do actually mix well, then yes, the grease would be washed out by the oil. If however there is only oil spray or mist, and the grease is insoluable in the oil, then the grease could survive in situ for a long time.

__________________

My (former...) ride: E-Sprit Fury (basis is the ZAP/Erider Thunder 5000) since May 03, 2011. Mods: Battery temp. gauge and battery heating (off the grid and off the battery), Kelly KEB72801X, reverse activated, luggage rack with topcase, HC Cycle Analyst, Emsiso BMS2405, 35mm² battery cables, now wrecked

Frolle
Offline
Joined: 05/11/2012
Points: 46
Re: Gearbox bearing fun

ofx210p:
I am eager to get the dimensions of the bearing.
The seal I have on my bike is leeking a lot, and it seams close to impossible to get this 100mm / 82mm / 8mm seal with the extra dust-lip.
So my plan is to see if it possible to get a rubber sealed roller bearing to maybe prevent some oil leakege.

So as soon you get the dimensions of your bearing, I wold be happy to know!

// Frolle

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

Just so you know - the seal is a seperate item. The bearing is also seperate.

I will get you all the correct part sizes from my bearing supplier in the next 48hrs and i'll post all here.

Cheers

Chris

Frolle
Offline
Joined: 05/11/2012
Points: 46
Re: Gearbox bearing fun

Yes, I am aware that the seal and bearing are separate items.
But I had an idea that if it is possible to get a bearing with built in rubber-seals it might prevent future oil leaks.
This original seal with the extra dust lip seam to be hard to get, at least here in Sweden.
So my plan B is to get a sealed bearing for double protection.

Can live without the extra excitement the always lubricated tire gives me...

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

I'll happily get one for you.

The stock codes from the supplier for the bearing and seal are
NACHI DEEP GROOVE BALL BEARING Stk no. 6915-2RS
which if you look it up is 75x105x16

http://www.amazon.com/6915-2RS-Bearing-75x105x16-Sealed-Bearings/dp/B005O1BYSC

The seal It cost me $15 NZD so you are welcome to have one at that price plus postage to sweden.
its code was M82-100-8

https://www.landefeld.de/artikel/en/rad-wellendichtring-nbr-idxadxb-82x100x8/WEDI+82/100/8A
this is a german website that i am sure would deliver to sweden !

Frolle
Offline
Joined: 05/11/2012
Points: 46
Re: Gearbox bearing fun

Grrr... They will not shop the bearing directly to Sweden, but I can bounce it via a contact in US.
Found it here in Sweden but with a $200 price tag, instead of $69 at Amazon.

But the seal is not with the extra dust-lip like the original one, if I understand correct?
I do not know if it makes any difference, maybe it is better since the original one is leaking :-)

Paco
Offline
Joined: 11/02/2011
Points: 30
Re: Gearbox bearing fun

Have you guys considered using ceramic bearings (to save a few milliwatts) ?

Frolle
Offline
Joined: 05/11/2012
Points: 46
Re: Gearbox bearing fun

Nope, never thought about ceramic bearings, and I guess it would be tough to find this not so common size with ceramic balls.
I doubt it would make any different.

And thanks to you ofx210p for sharing your measures, it will save me a lot of time to have the correct parts ready when it's time!

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

ofx210p wrote:

So, if you take the side of the swing arm off and unbolting the large nut as if to remove the back wheel and then, grab the tyre and see if there is any movement. If there is - the bearing on the back is toast.

I'm not sure that this part of your post is necessarily correct though. The large diameter bearing is actually relatively small width and it is highly likely that there will be some movement if the hub is pulled side to side. Most bearings have a built in tolerance to adapt to heat and tighten up when under load. Obviously if it's excessive, especially in an up down/forward back movement if grabbed at the left side of the hub, then the bearing would need renewal.

Personally, having stripped my gearbox, I'm more concerned about the needle roller bearings on the three planetary gears. They look like they might have quite a hard life. Does anyone have the spec for those?

There's also the other large bearing on the outer gearbox casing. Ideally, I'd like to replace them all, so if anyone has the specs, that would be good. I found the right hand oil seal on eBay for a couple of quid, delivered.

I think to a great degree the noisiness of the gearbox is due to the straight cut gears. Helical gears would have been a lot quieter (and more expensive, one assumes). I built an e-bike using a motor with similar gears and it was noisy because it had metal straight cut gears (Heinzman motor). I built another using a Bafang motor which has plastic gears and it's virtually silent. Of course, the Vectrix ones are hefty and very big, so, I suspect, noisy as a result of that. Has anyone tried running with more than 80cc of oil and using, say, 70W viscosity?

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

PS

For some reason, I'm not allowed to post any new threads... (anyone know why?) so I'll have to ask here. I see that the Vectrix lights are on permanently when the 'ignition' switch is on. ie like most motorbikes made after 2005/6. Whilst the rear lights are LED and relatively low drain, the headlamp must use a lot of power? Has anyone tried putting an on/off switch onto the headlamp of a Vectrix? Mine has like a day-riding sidelight thing under the main beam and that one's on all the time too.

I realise that it's supposed to be a safety feature having headlamps on in the daytime (although there are two schools of thought on that) but it seems like a lot of draw on an electrically powered machine. Would a Vectrix run OK without the headlamp on or would the controller or other electrical gubbins start doing anything funny, do you think?

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

James

A couple of things

1. You are correct - some movement on that bearing is normal and there are no specs on what is excessive so that would have to be a personal judgement call.

2. I agree all the bearings need ideally to be replaced in one go and i also agree the needle rollers in the 3 planets have it hard. I havent yet got the specs on the other bearings, however I will be replacing as many as i can - when i get a chance - life is a bit busy currently.

3. I have tried 70w90 and it was ok however i have gone back to shockproof redline 70w-90 which is thinner but has the same shear ratings. I also tried with 100cc and it leaked quite considerably (pressurised at 100kmh ?)

Other concerns is that the bearings on one of my boxes seemed to have white grease in them which didnt seem to mix with the lubricating oil. All other greases i have found seem to wash into the oil fairly soon after rebuild. I am unsure exactly what that white grease is (or indeed if it is just an amalgamation of oil/water)

Lastly I found that replacing the rear bearing with a sealed one is detrimental to the systems because the sealed bearing has too much friction / stiction to overcome. For requirements of low downtime, I swapped boxes rather than remove the seals which i will do when replacing other bearings etc.

On your point about the helical gears and straight cut. Helical gears would always be wanting to move sideways (due to their nature) and therefore need to be spaced/thrust washered wouldn't they. Apparently the best (and most expensive option for both quietness/ efficiency and loading are chevron cut gears as they dont have lateral movement but cost an arm and a leg to manufacture - however i'd have thought that simply cutting a helical gear vertically and reversing oneside and bolting/bonding two opposing sides together would achieve the same mechanical system.

An engineer i spoke to recently did also mention the Nylon or Fibre option on the gears. I wasnt aware that camshafts on older cars ran nylon gears. I used to own a sinclair C5 and that was nylon geared but its loads were less. It certainly would be quieter and therefore ???? more efficient as isnt noise a result of inefficiency in this system so to speak.

Anyhow - interesting subject as my gearbox plays on my mind constantly.

Lights - you have a 20,000w motor (i am probably wrong on that spec but lets just assume for arguments sake) and a 35w light bulb. The 35w bulb is such a small drain for the period of time you are running the bike (0.00175% of its power consumption), i would suggest it is rather insignificant. However should you wish to turn the main bulb off and run with the LED one only - there is a "magic sequence" to make this happen on some versions of the bike firmware - simply check out the online collaborative handbook for information on what levers to pull on the bike to make that happen.

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

Thanks for the above post. I did indeed check through the collaborative handbook after you suggested it. The site is so big that I missed it!

My headlamp thing is now settled. Here's me thinking of a toggle switch in the wire..... instead of which, all I have to do is hold the headlamp flasher switch and wait 10 seconds or so, until the horn has bibbed twice, and the headlamp goes off, leaving the only 'pilot bulb' and rear LED's lit. Everything resets to default on switching off the key. Perfect!

Also, I had been irritated by the windshield clonking up and down and making quite a racket when going over bumps. On the same trawl of the handbook, I found the fix suggesting grinding a few millimetres off the four locating pegs on the alloy plates that hold the windscreen on. I've just done that and it's a big improvement.

I then checked throttle calibration (bang on 43kph) and the encoder calibration (fine) and the motor phase check (fine).

Now all I need to do is find out why I can't put new posts on the forum.

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

ofx210p wrote:

Lastly I found that replacing the rear bearing with a sealed one is detrimental to the systems because the sealed bearing has too much friction / stiction to overcome.

What makes you say this? Or is it an educated guess? There's quite a bit of stiction on the two oil seals though, right? I wondered about the lubrication aspect of this bearing. I wondered maybe whether one of the seals in the bearing could be pried out (they do come out easily enough, I've found) on the side pointing inwards. Oil would get into the bearing and there'd effectively be a triple seal on the left of the gearbox... the seal left in the bearing itself and the double lipped oil seal.

I may get a contact in the USA to send one of those large bearings to me from Amazon.com. I tried buying one earlier but they won't ship anywhere except the USA......I know someone who will buyone and post it to me as I have done for motorbike spares for him...... If you want one, let me know and I'll get him to send me two.......

ofx210p
Offline
Joined: 10/20/2008
Points: 375
Re: Gearbox bearing fun

Quite simply, i fitted one only to find the rear was simply harder to spin even without the rest of the gearbox fitted. I then proceeded to fit the rest of the gearbox and could 'feel' the machine working harder at all speeds. I dont have the cycle analyst fitted to be able to give you figures but it was distinct enough to know that running it with seals is not the best option and probably why they went originally for the open bearings, oil lubricated with seals at each end of the box.

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

For some reason, I'm still not allowed to post new contents on any of the forums. So I'll have to post here instead.

I just bought 4 of the large oil seals which go on the left of the Vectrix gearbox. I wanted one for myself and found that there was a surcharge on small orders, so I thought it would be better for me to buy four of them instead of only one. I therefore have three available.

If anyone wants one, please e-mail me on geewells@tiscali.co.uk Failing that, I'll put them up for sale on eBay with a bit added on to cover their costs etc.......

Omange
Offline
Joined: 11/20/2012
Points: 3
Re: Gearbox bearing fun

jamesengland wrote:

PS

For some reason, I'm not allowed to post any new threads... (anyone know why?) so I'll have to ask here. I see that the Vectrix lights are on permanently when the 'ignition' switch is on. ie like most motorbikes made after 2005/6. Whilst the rear lights are LED and relatively low drain, the headlamp must use a lot of power? Has anyone tried putting an on/off switch onto the headlamp of a Vectrix? Mine has like a day-riding sidelight thing under the main beam and that one's on all the time too.

I realise that it's supposed to be a safety feature having headlamps on in the daytime (although there are two schools of thought on that) but it seems like a lot of draw on an electrically powered machine. Would a Vectrix run OK without the headlamp on or would the controller or other electrical gubbins start doing anything funny, do you think?

As you mentioned LIghts are on every time their must be some grounding issue

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

Omange wrote:
jamesengland wrote:

PS

For some reason, I'm not allowed to post any new threads... (anyone know why?) so I'll have to ask here. I see that the Vectrix lights are on permanently when the 'ignition' switch is on. ie like most motorbikes made after 2005/6. Whilst the rear lights are LED and relatively low drain, the headlamp must use a lot of power? Has anyone tried putting an on/off switch onto the headlamp of a Vectrix? Mine has like a day-riding sidelight thing under the main beam and that one's on all the time too.

I realise that it's supposed to be a safety feature having headlamps on in the daytime (although there are two schools of thought on that) but it seems like a lot of draw on an electrically powered machine. Would a Vectrix run OK without the headlamp on or would the controller or other electrical gubbins start doing anything funny, do you think?

As you mentioned LIghts are on every time their must be some grounding issue

No, it's not that. The Vectrix lights are set to on by default, apparently. Holding the headlamp flasher button until two beeps of the horn are heard results in the main headlight going off.

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

ofx210p wrote:

James

1. You are correct - some movement on that bearing is normal and there are no specs on what is excessive so that would have to be a personal judgement call.

2. I agree all the bearings need ideally to be replaced in one go and i also agree the needle rollers in the 3 planets have it hard. I havent yet got the specs on the other bearings, however I will be replacing as many as i can - when i get a chance - life is a bit busy currently.

A quick follow-up. I just replaced all the bearings and oil seals in the complete gearbox. I used 'standard' bearings, not the C3 larger tolerance versions. Now, it is clear that, although the bearings are a tight fit in the housings and are brand new, there is still some 'play' ie waggle left to right at the endge od the gearbox or cover. It's quite a distance from the bearing to the rim of the box/cover and eny play is exaggerated accordingly. There is no play at all if an axle is put throught the bearing and the box lifted up/down.

The old needle bearings, which have done 19,000 miles, seemed fine when in the planet gears but, out of them, and completely stripped of oil by trichloroethylene, it was clear that they had play, made a sound and had a gritty feel. They were all in a similar state. One thing... the gears are pretty poorly machined. I've never, ever seen such poorly machined gears come out of any Japanese motorcycle. Not ever. They reminded me of tractor gears made in India (of which I've seen a lot) with tooling marks, varying tolerances etc.

The large oil seal on the left of the gearbox, nearest the motor, looked fine but, on closer inspection, was worn on the inner lip and had quite obviously seeped some oil. This would account for the small amount in the gearbox (about 30cc). The smaller seal on the gearbox cover was more worn and had seeped oil. I replaced both seals.

I also added an extra seal to the motor shaft. This seal is what appears to stop the gearbox oil from entering the motor (the large seal on that side merely stops the oil from coming out of the gearbox around the circumeference of the box). The OEM seal is fitted from the motor side but I found it possible to add an extra oil seal from the gearbox side. There's plenty of room for one and no danger of it coming out because it's held in at 5 points round the rim by the 5 bolts through the alloy part of the gear 'spider' bit. I figured that having two lines of defense against gearbox oil ingress into the motor can only be a good thing. And, if the friction caused by one little oil seal can adversely affect the performance of a 65mph electric scooter, I'd be very surprised indeed.

The seal renewal and the additional motor shaft seal mean that I feel easier about having the more oil in the gearbox (130ml). The box breathes through the gauze-topped nut at the top anyway, so it's not like there's any pressure in there.

Whilst my gearbox was not especially noisy to start with, doing the above has without doubt made it quiter and it's nice to ride knowing that the bearings have all been done.

A couple of things sprang to mind whilst doing the above. The spider has a narrow channel at each trunnion point, in order to lubricate the needle bearing. It could be possible to fill the needle bearings with grease and seal it in with silicone. This is done on exposed UJ joints of some shaft-driven motorcycles. OK, these joints aren't sitting in oil but the seals generally hold the grease in. Also, the planet gears have quite considerable end float. I put a washer of PVC bearing shim material onto the three points on the spider. This is a durable material meant for shims and it will be sitting in oil anyway. The oilway to the bearing is still unimpeded.

I'm going to give the above a thorough test as soon as I get a new front tyre on. My bike had the original Pirellis and they were hard and worn. I've replaced the back and am waiting for the front one to be delivered. So, weather permitting, I'll get back with a follow up soon......

jamesengland
Offline
Joined: 10/26/2012
Points: 144
Re: Gearbox bearing fun

jamesengland wrote:
ofx210p wrote:

James

1. You are correct - some movement on that bearing is normal and there are no specs on what is excessive so that would have to be a personal judgement call.

2. I agree all the bearings need ideally to be replaced in one go and i also agree the needle rollers in the 3 planets have it hard. I havent yet got the specs on the other bearings, however I will be replacing as many as i can - when i get a chance - life is a bit busy currently.

A quick follow-up. I just replaced all the bearings and oil seals in the complete gearbox. I used 'standard' bearings, not the C3 larger tolerance versions. Now, it is clear that, although the bearings are a tight fit in the housings and are brand new, there is still some 'play' ie waggle left to right at the edge of the gearbox or cover. It's quite a distance from the bearing to the rim of the box/cover and any play is exaggerated accordingly. There is no play at all if an axle is put throught the bearing and the box lifted up/down.

The old needle bearings, which have done 19,000 miles, seemed fine when in the planet gears but, out of them, and completely stripped of oil by trichloroethylene, it was clear that they had play, made a sound and had a gritty feel. They were all in a similar state. One thing... the gears are pretty poorly machined. I've never, ever seen such poorly machined gears come out of any Japanese motorcycle. Not ever. They reminded me of tractor gears made in India (of which I've seen a lot) with tooling marks, varying tolerances etc.

The large oil seal on the left of the gearbox, nearest the motor, looked fine but, on closer inspection, was worn on the inner lip and had quite obviously seeped some oil. This would account for the small amount in the gearbox (about 30cc). The smaller seal on the gearbox cover was more worn and had seeped oil. I replaced both seals.

I also added an extra seal to the motor shaft. This seal is what appears to stop the gearbox oil from entering the motor (the large seal on that side merely stops the oil from coming out of the gearbox around the circumeference of the box). The OEM seal is fitted from the motor side but I found it possible to add an extra oil seal from the gearbox side. There's plenty of room for one and no danger of it coming out because it's held in at 5 points round the rim by the 5 bolts through the alloy part of the gear 'spider' bit. I figured that having two lines of defense against gearbox oil ingress into the motor can only be a good thing. And, if the friction caused by one little oil seal can adversely affect the performance of a 65mph electric scooter, I'd be very surprised indeed.

The right side bearing inner race was a total swine to get off the axle. In the end, I used a bench grinder, very carefully, to flatten it almost to the shaft. This allowed it to spin off. Putting the new race on was dead easy. I put the spider in the freezer for an hour and then heated the new inner race in the kettle. The hot race slipped easily over the frozen shaft and immediately shrank firmly into position. No banging or bashing it on.

The seal renewal and the additional motor shaft seal mean that I feel easier about having the more oil in the gearbox (130ml). The box breathes through the gauze-topped nut at the top anyway, so it's not like there's any pressure in there.

Whilst my gearbox was not especially noisy to start with, doing the above has without doubt made it quiter and it's nice to ride knowing that the bearings have all been done.

A couple of things sprang to mind whilst doing the above. The spider has a narrow channel at each trunnion point, in order to lubricate the needle bearing. It could be possible to fill the needle bearings with grease and seal it in with silicone. This is done on exposed UJ joints of some shaft-driven motorcycles. OK, these joints aren't sitting in oil but the seals generally hold the grease in. Also, the planet gears have quite considerable end float. I put a washer of PVC bearing shim material onto the three points on the spider. This is a durable material meant for shims and it will be sitting in oil anyway. The oilway to the bearing is still unimpeded.

I'm going to give the above a thorough test as soon as I get a new front tyre on. My bike had the original Pirellis and they were hard and worn. I've replaced the back and am waiting for the front one to be delivered. So, weather permitting, I'll get back with a follow up soon......

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
Customize This