Topic: Engine Bearing Replacement

[odin836]

Engine Bearing Replacement...

Thought this might help a few people and give me the opportunity to pose a question... 

Has anyone ever had the channel in a bearing for ball bearing setting machined wider to take the stock honda setting (eg. Part 13496-300-000)? 

Replacement bearing details.

Primary Tensioner
Honda Code
91004-300-000 - Unavailable
NTN Bearings Code
NTN6008NR
(Channel in bearing for setting not wide enough, will need machining)

Final Drive Shaft
Honda Code
91996-300-008 - Unavailable
NTN Bearings Code
NTN6205

Honda Code
91008-300-008 - Unavailable
KSM Bearings Code
5206


Transmission
Old Honda Code
91002-300-008 - Unavailable
Current Honda Code
91003-612-004 – Available

Current Honda Code
91003-235-000 - Available

Current Honda Code
96100-63040-00 – Available

Current Honda Code
96100-62040-00 – Available


Still to replace the Clutch Bearing, once source I will update this post.

[mick7504]

No, never had any reason to do that and I reckon you'd be flat out like a lizard drinkin' trying to regroove a bearing case.
Aftermarket replacement bearings have never been a problem but you must use the original Honda half moon rings with the grooved bearings.
The grooved bearings generally come with a snap ring on them which are wider (not thicker) than the Honda rings and will go nowhere near fitting into the cases because of the larger diameter.
I'm assuming that this is what you're up against.
Here is a list of SKF bearing numbers that will cover the tranny from the kick starter to the gear lever.
They should be uniform numbers and or able to be cross referenced from all bearing suppliers.
2 x HK2520 Needle Rollers
1 x 3206ATN9 Roller Bearing
1 x 6003 Roller Bearing
1 x 6008NR Roller Bearing
1 x 6204 Roller Bearing
1 x 6205 Roller Bearing
1 x 6205NR Roller Bearing
1 x 6304 Roller Bearing
1 x 6304NR Roller Bearing
The "NR" designates a groove in the outer bearing case.
Hope this helps
Mick

[Ricky_Racer]

Mick, could you edit/repost your list with a reference to where each of these SKF bearings goes? Thanks, Mate!  RR

[odin836]

Yes, a description of what each bearing is for would certainly help...
Cheers

[mick7504]

No problem at all guys.
I only have a list of part numbers that I have used previously on hand at the moment and haven't catalouged where each one goes but that shouldn't be a problem.
I'll see if I can scan in an exploded view of the tranny with the part numbers next to each bearing.
What I can do in the meantime is give you the ID/OD and width of each bearing which will be a start at least.
Nailed to the floor with other work at the moment and will get onto that as soon as.
Mick

[Ricky_Racer]

Thanks, Bro! RR

[mick7504]

Here goes.

Some exploded views and the bearing numbers and sizes. OD x ID(Bore) x Width.
These are all SKF part numbers.
The "NR" after the number means that there is a groove in the outer bearing case.
Most bearing suppliers should recognise these part numbers although it is a good idea to always double check first before purchasing.

[odin836]

Thats great!
I'm sure this will help many people, esp since not all parts are available from Honda...

[mystic_1]

That should be added to the FAQ!

Thanks!

mystic_1

[odin836]

Whats the trick for removal of the HK2520 Needle Rollers from the Primary Drive?

Please dont tell me its a Honda Speciality Tool

[mystic_1]

This:



Blind Bearing Puller

Rent one at your local autoparts store.

mystic_1

[mick7504]

Here is another "Non Honda Specialty Tool" for installation.

Home grown and works like a treat.

Mick

[odin836]

Mick, hows the home grown tool work?
Doesn't look like it will punch it down...
Doesn't look like it will pull either...

[mick7504]

This is used for installing the needle roller bearings.
It locates neatly inside and contacts the outer edge to eliminate the possibility of damage to the bearing during installation and also assists in guiding it straight.
I use a soft faced hammer to do this. (See Pics)
It has nylon heads which are replaceable and they are a good investment when working on these engines as they will not bruise the metal. (Covers,cases etc)
The brand name is "Thor" and are one of the better ones to buy.
Firm force is needed but not brutal force - There is a difference.
Mick

[the-chauffeur]

Guys, I have a correction/addition for you in relation to one of the bearing no's above - and it's an expensive one to get wrong (don't ask).

My K2 has a different final drive bearing to the one listed above - very different.  The bearing in question is labelled in the diagram above as 3206ATN9.  On my K2, the bearing I've just detached from the drive shaft is a 6305 - looks like the shaft size on my K2 is narrower than Mick's.  The key differences are the internal diameter and the bearing depth. 

The 3206ATN9 has an internal diameter of 30mm and a depth of 23.8mm
The 6305 has an internal diameter of 25mm and a depth of 17mm

Oh, and the other big difference is the price.  The 3206 cost me about 6 times more than the 6305.

Hope that helps.

[mick7504]

Hi mate
What you have there is an early model final drive with the single row bearing. (6305)
These bearings are a reasonably common run of the mill bearing that suit a variety of different applications (Automotive and Industrial)
Some info here on the Satanic Mechanic (Axl's) site.
http://www.satanicmechanic.org/gearbox.shtml
Thanks for sharing.
Mick

[the-chauffeur]

Ah, that'll be why it's different.

Since the later bits are interchangeable, am I right in thinking it might be an idea to get hold of a later final drive for longevity/smoothness?  Looking at the bearings, the later ones are far more substantial than the earlier ones.

Any thoughts?

[mick7504]

Ah, that'll be why it's different.

Since the later bits are interchangeable, am I right in thinking it might be an idea to get hold of a later final drive for longevity/smoothness?  Looking at the bearings, the later ones are far more substantial than the earlier ones.

Any thoughts?

Definately for sure mate.
More balls are always better. 

[Gaither]

Thanks, Mick (and others). LOTS of good info here!!!

PLEASE DO post this valuable info in FAQ.

FWIW, if you have a bearing in your hand, in MOST (but not all) cases, a comprehensive Industrial Bearing Supply House can come up with the same bearing (or a usable substitution).

A time or two (antique cars), I've had to buy bronze "Oilite" stock and have it machined to the orig bearing specs. Although in a lot of cases, this will NOT make a suitable substitution.

Great research and info here from you guys.

Thanks 

[HondaMan]

Edit: 6/2015---
One thing I'd like to add: the bearing #23 (thanks, Kickstart!) in this picture is an "Extra Clearance" bearing. While standard bearings will work, they will make the shifting of gears 3,4 & 5 stiff when the engine is hot or under power because of the twisting of the crankcases. The Extra Clearance bearings can be had from any bearing house: they are usually associated with very tight press-fitted holes, but here they serve a different purpose. The Extra Clearance is about 0.0004" in the races, to prevent bind and power loss (and extra heating). 

A local bearing house has told me that since 2008 or so, the "normal" bearing clearance has become, through general usage, the old C3 classification. It was, for many years, the C2 as "normal", now not so. This C3 class is also now known as the "electric motor bearing" class.

[strynboen]

there are c kodes on bearings..ect 6205-c3..c-3 are with bigger"vider" tolerance then c-2

[mick7504]

Mark (Hondaman)
That's a good point about the internal clearances mate. 

Terry
These a are quality bearings and there isn't one that has Chinese or Taiwanese origins.
Glad it helps mate. 

Mick

[Terry in Australia]

Thanks Mick, I've used SKF bearings before with no issues, they were great. 

[HondaMan]

Thanks Mick, I've used SKF bearings before with no issues, they were great. 

Me, too, but I had to take out a 2nd mortgage to get them. 

[wohali]

Hi folks,

Just ordered these bearings for my '78 F3 - thanks SO MUCH for putting this all together in one place!

For my Canadian friends, don't mess around with the motorcycle shops, who are going to overcharge you anyway, and possibly not get you good parts. Go straight to the source: Canadian Bearings. They're uber-friendly and will take your order right over the phone with a CC. They also have walk-up counters all over Canada.

For a full set of engine bearings, all SKF-made with two exceptions (see below), the price wasn't bad compared to marked-up poorly made Chinese bearings!

Bearing	Price (CAD)
HK2520 Koyo	12.18 ea (24.36)
3206ATN9/C3 SKF	61.73
6003 SKF	16.95
6008NR SKF	47.75
6204 SKF	9.80
6205 SKF	10.55
6205NR/C4 NTN (*)	17.55
6304 SKF	13.00
6304NR SKF	23.11
Subtotal	224.80

The salesperson also stated that SKF doesn't make the metric needle bearings, so I went with her suggestion of Koyo ones instead.

Unfortunately, for the 6205NR/C3, there was no stock anywhere in Canada. They were able to locate an NTN /C4 clearance bearing locally, so I decided to go with that, versus no extra clearance and having the sticky 3-4-5 gear shifts Hondaman mentions above. The ranges of tolerance overlap anyway.

Canada Bearings assured me repeatedly that the NTN bearing would be of the same quality as the SKF bearing.