MYSTERY BEARINGS in Aero 125

[motormike]

I have discovered that there are six bearings associated with the transmission in Aero 125.
Input shaft = 2 (radial ball type)
Counter shaft = 2 (needle type)
Final drive shaft = 2 (radial ball type)
Makes sense doesn't it ?
Parts fiche shows input and final, but I am not seeing the counter-shaft bearings listed.
This is something I will have to take up with a parts-man I guess.
Anybody have an insight here, am I missing something ?
TIA...................mike O'th motor............

[motormike]

...The service manual shows pix of the needle bearing on page 9-4,
but does not include it in the schematic on page 9-0...
....nor does it tell about removal/installation...

[vette76]

when buying parts for my sa-50, i got screwed the first time because it lists half the bearings/seals, under "transmission", and half under "crank case" maybe it will be the same for you.

[breaze]

...The service manual shows pix of the needle bearing on page 9-4,
but does not include it in the schematic on page 9-0...
....nor does it tell about removal/installation...

I agree with Vette76 about looking in the parts fiche under 'crankcase' to find all the transmission bearings - I've had the same experience.

Also, ODKiller had a post not too long ago about a 125 he wanted to sell. He is in Elizabethton, Tenn. and was asking a very reasonable price. I pm'd him about the possibility of selling parts but did not hear back. That may be a possibility for finding your discontinued transmission parts.

http://www.hondaspree.net/phpBB3/viewto ... =2&t=25852

[noiseguy]

I just looked and can't find them either... A thought on this... needle bearings are typically very long-lived, and with the bearing being pressed into a blind hole, it may not be a "replaceable" part... it may come with a newly-ordered case. So... do you really need it replaced? If so, perhaps you can source the needle bearings loose and re-use the housing? Spree cases are same... the input shaft runs on the case with no bearing, so if that surface wears out, the case is "trashed." I'm not saying you can't get it out and/or replace it... I'd just give serious thought before proceeding.

The rest is a thread highjack on bearings

As an aside, Honda's not the only source for those bearings. Usually bearing size / type is listed in the microfiche. You can use that information to go to a bearing shop and order the bearings... they are standard parts, after all. You don't typically save much/any money going this route vs Honda, but worth checking. Esp. if you're working on a rare / unusual / exotic bike, where OEM parts get ratcheted up on you.

If the microfiche doesn't list the sizes, get out your calipers / micrometer, measure the parts, and head in with that. Or take the whole thing with you (call ahead first) and see if they can measure it. Press in bearings will be slightly larger than the hole they go into (transitional or interference fit) and slightly smaller that any shaft that runs through them (running clearance.)

Same goes for o-rings... sizes listed usually, except with o-rings you'll probably save money going to the hardware store. And the black, nitrile o-rings that they sell are identical to what the OEM carries; fuel and temperature safe... don't let anyone tell you differently.

Here's what I mean by standard bearings listed in the microfiche, these from crankcase:
24: 073834-4 BEARING (6201)
25: 072219-9 BEARING (6203)
26: 091412-7 BEARING (6204)

See those numbers in parens at the end of the part listing? Those are standard bearing size numbers... a 6201 bearing is a standard size, and will fit in that application.

Bolts are listed too... I'll pull the microfiche to re-assemble motors from a bag of bolts so I know I get the right bolt in the right hole.

[motormike]

The needle bearing pictured below was very long-lived...28 years.
I considered that these needle bearings might be located in the crankcase fiche, regardless of how LITTLE sense that made.
I acknowledge the bearings as being standard as indicated by the #'s
All ball-bearings in my trans are seemingly undamaged,... ... but I consider it a risk to continue to use them after being run in the gear oil with needle bearing debris permeating the whole mess.
That needle bearing debris did a major number on the gears and concerns me about the possible damage to all components.
Made contact with ODkiller, THANKS AGAIN breaze ! !
His Aero is still available and we may be able to come to an agreement...only draw-back is the 6-hour drive to get it....
Thank you ALL for the replies....

[Tyler VR]

That bearing looks even more worn through than mine was....

I spent some time looking at parts diagrams when I took apart the trans on my spare nh125 and didn't have any luck either. The gears have me more worried, I wish there was info on interchangeable gears for larger honda scooters. I figure there has to be some common gears from like a ch125 or another larger model scooter. My plan for the bearings is to first try a local bearing shop here, I've been told they can get any bearing.

There's nh125 engines on ebay right now, but overpriced.

[noiseguy]

Interesting. Well, at least you don't have to worry about removing the bearing... it's already 1/2 way out.

If you all find a bearing that works, post it up here for posterity.

To your point, I'd be very surprised if you couldn't find an equivalent gear set from another bike that is higher volume.

[nunnsie]

The needle bearing pictured below was very long-lived...28 years.
I considered that these needle bearings might be located in the crankcase fiche, regardless of how LITTLE sense that made.
I acknowledge the bearings as being standard as indicated by the #'s
All ball-bearings in my trans are seemingly undamaged,... ... but I consider it a risk to continue to use them after being run in the gear oil with needle bearing debris permeating the whole mess.
That needle bearing debris did a major number on the gears and concerns me about the possible damage to all components.
Made contact with ODkiller, THANKS AGAIN breaze ! !
His Aero is still available and we may be able to come to an agreement...only draw-back is the 6-hour drive to get it....
Thank you ALL for the replies....

Hi,

Did you ever figure out the needle bearing part number or did your local bearing shop find something suitable?

[Tyler VR]

Hi,

Did you ever figure out the needle bearing part number or did your local bearing shop find something suitable?

I got the part number off mine and ordered one from ebay.

INA HK1412
http://www.ebay.com/itm/INA-HK1412-Need ... Swr~lYtG00

[motormike]

Did you ever figure out the needle bearing part number or did your local bearing shop find something suitable?

I did not replace the bearing in my transmission case,
but rather replaced the entire trans cover complete with bearing...
BTW, I have since parted a NH125 and have saved the gear set and many other parts should you need something.

[noiseguy]

Bearing listed as: INA HK1412 Needle Brg, Drawn Cup, Bore 14mm, OD 20mm

[nunnsie]

Hi,

Did you ever figure out the needle bearing part number or did your local bearing shop find something suitable?

I got the part number off mine and ordered one from ebay.

INA HK1412
http://www.ebay.com/itm/INA-HK1412-Need ... Swr~lYtG00

Big thanks, really appreciate it!

[nunnsie]

Did you ever figure out the needle bearing part number or did your local bearing shop find something suitable?

I did not replace the bearing in my transmission case,
but rather replaced the entire trans cover complete with bearing...
BTW, I have since parted a NH125 and have saved the gear set and many other parts should you need something.

Thanks, Mike, I'll keep that in mind. I had a spare engine case and salvaged the gears and trans cover from it. However, I'm still hearing a whine at speed, so I'm thinking I should replace the bearings while I'm at it. It's a buddy's bike and it's been ridden hard (over 16k miles), so I'd love to get it to a happier place so it can do many more miles.