Made in Japan layshaft bearing

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bentrod

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After stumbling on Bitchenbeezers threat that lead to the problems with layshaft bearings I decided to take my trans apart just for peace of mind. The transmission is on the bike. This is the layshaft bearing I removed.

Made in Japan layshaft bearing


I read where the bad bearings were from Portugal, seeing how this is from Japan, is it safe to put it back in? BTW, in one of the threads discussing the removal of the bearing, someone suggested that if the layshaft did not come out you should just heat the case with a heat gun, then just pull out the shaft with the bearing attached. That's what I did, it worked perfectly. Just endless great information on this site.

Art
 
Would you by chance have the information on the SKF bearing, what bearing ID numbers and where I might be able to order them from?

Thanks, Art
 
If it rolls smooth put it back in.

I'll probably go with a ball bearing over the roller bearing next time.
 
I got the upgrade ball bearing from Mick Hemmings, the roller bearing is too "shimming-sensitive" for my taste.

Vince
 
bentrod said:
I read where the bad bearings were from Portugal, seeing how this is from Japan, is it safe to put it back in?
Click to expand...

While it is certainly true that the factory-fitted Portuguese-made FAG 6203 bearings often failed prematurely, they were not the only Commando layshaft ball bearings known to break up.
Any metal-cage layshaft ball bearing could, potentially, break up, so in my opinion it would be something of a false economy to re-use the old layshaft bearing, (as it's the cage rather than the bearing itself that fails) therefore I would seriously suggest you consider fitting either the roller bearing upgrade, or the "textile" cage FAG 6203TB.P63 as used and recommended by Mick Hemmings.
 
L.A.B. said:
bentrod said:
I read where the bad bearings were from Portugal, seeing how this is from Japan, is it safe to put it back in?
Click to expand...

While it is certainly true that the factory-fitted Portuguese-made FAG 6203 bearings often failed prematurely, they were not the only Commando layshaft ball bearings known to break up.
Any metal-cage layshaft ball bearing could, potentially, break up, so in my opinion it would be something of a false economy to re-use the old layshaft bearing, (as it's the cage rather than the bearing itself that fails) therefore I would seriously suggest you consider fitting either the roller bearing upgrade, or the "textile" cage FAG 6203TB.P63 as used and recommended by Mick Hemmings.
Click to expand...

This is exactly what I did about a month ago.
I also found a Japanese ball bearing when I went in.
The bike was laid up in 1977 so it must have had an early swap of bearings,

"textile" cage FAG 6203TB.P63
Heat case and freeze layshaft with bearing mounted and it went in real slick.
Nice not to have to fool with shimming end play needed with roller bearing.
 
Roller takes way more power/abuse than any ball. Think about the drive-side forces. Go ahead and use a ball ,it's your gearbox.
 
Torontonian said:
Roller takes way more power/abuse than any ball. Think about the drive-side forces. Go ahead and use a ball ,it's your gearbox.
Click to expand...

I deferred to Mick Hemming's recommendation for his special ball bearing based on his many years of expertise in Nortons and their care.
Unless you are planning to pump a lot more horsepower through the box than a typical Norton does he apparently dosen't think a roller is necessary.

Here is a look at the bearing. I was able to get it stateside from a dealer by Googling the number and seeing what popped up.

hemmings-layshaft-bearing-t5838.html
 
Jim I know your expertise. Not questioning it. If you want to research roller vs. ball for this particular application be my guest. My vote is roller. Convince me different. 3 rollers in 3 Nortons , the fear kicked in when an original (not portuguese) left me glad to be alive and hobbling home in 2 nd. but SLOW. Think about it ,load forces strongest on driveside ,splay out the forces to rollers. German yes.
 
Torontonian said:
Jim I know your expertise. Not questioning it. If you want to research roller vs. ball for this particular application be my guest. My vote is roller. Convince me different. 3 rollers in 3 Nortons , the fear kicked in when an original (not portuguese) left me glad to be alive and hobbling home in 2 nd. but SLOW. Think about it ,load forces strongest on driveside ,splay out the forces to rollers. German yes.
Click to expand...

I am definitely in favor of the roller bearing also. It has proven to be the long lasting choice on stock or built engines. It was also the choice of the Norton factory after the Portuguese bearing fiasco.

There is also a lot of talk about the need to shim the layshaft when installing a roller bearing. If you study the design of the Norton gearbox you will see there is no more need to shim with a roller bearing than there is with a ball bearing. If your gearbox worked fine with a ball bearing then it will work the same after installing a roller.

For best gearbox life the layshaft should be shimmed whether you run a ball or a roller.

Cutting down on the endplay it will increase the depth of engagement of the dogs which makes them last longer and helps keep them from pushing the gears apart which wears or bends the shift forks. Jim
 
Yes, agree.. Im a little bent in the head when it comes to layshaft bearing replacement as I continue to believe it is the single most important thing an owner needs to do.
 
Torontonian said:
Yes, agree.. Im a little bent in the head when it comes to layshaft bearing replacement as I continue to believe it is the single most important thing an owner needs to do.
Click to expand...

You will not get any argument from me. My first layshaft bearing experience was at the end of a freeway on-ramp shortly after I built my Commando. It ended up as a pretty easy high side but I was lucky.

That is the first thing I look at before I put an unknown bike on the road. Jim
 
rx7171 said:
Torontonian said:
Roller takes way more power/abuse than any ball. Think about the drive-side forces. Go ahead and use a ball ,it's your gearbox.
Click to expand...

I deferred to Mick Hemming's recommendation for his special ball bearing based on his many years of expertise in Nortons and their care.
Unless you are planning to pump a lot more horsepower through the box than a typical Norton does he apparently dosen't think a roller is necessary.

Here is a look at the bearing. I was able to get it stateside from a dealer by Googling the number and seeing what popped up.

hemmings-layshaft-bearing-t5838.html
Click to expand...

In a visit to his shop last year I had a very informative dialogue with Mick Hemmings on the subject, and his opinion of the roller bearing was brief and unprintable.
Yes, he has a vested interest in the fibre cage bearing, and if you want a Quaife box he's the only guy to deal with. I'm happy that the assessment is sound on engineering principles alone.
I'm also uncomfortable with the principle of not shimming the layshaft if a roller is used - I shimmed mine with .020" of iso shims to get the endfloat to tolerable levels, and when I went back last year I had to add another .040". Given that this has a direct 'bearing' *ahem* on the engagement of the gear dogs, mine is going to be replaced at the earliest opportunity.
 
Mick has been updating the original ball bearing with the fiber cage bearing for a long time -long before the Portuguese bearing fiasco. He did it because the original roller bearing was not up to racing abuse. It was a good update and I respect him for sticking with it.

The HD ball bearing will handle the load with no problem and it will not come apart like a steel caged bearing does in that application. Like any ball bearing operated in a "dirty "environment it will eventually wear the grooves and get noisy. I would expect at least 30,000 miles out of one on the street. In many cases that is good enough.

The roller will last longer. I know of one [in my bike] with over 100,000 miles. I will be heading out this weekend for a 5000 mile ride and I will not have to worry about it . Jim
 
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