Ironhead Pinion shaft roller bearing plug fit

[Jaime1840]

Originally Posted by ryder rick

What year cases?
I think 84 & 85 had a needle bearing

Hey rider rick,

The cases are from 1974.

[Jaime1840]

Originally Posted by IronMick

Sorry. What I see in the link is no picture of the parts you were discussing, only some advertisements, some of which I would not show my children

Hey Ironmick,

I don´t know man, when I click on it there is no advertisements, just the picture of the thread Im talking about.

cheers

[IronMick]

Originally Posted by Jaime1840

Hey Ironmick,

I don´t know man, when I click on it there is no advertisements, just the picture of the thread Im talking about.

cheers

These things happen from time to time, depending of what site the pic is hosted on, the geographical location of the people, the type of membership [privacy, advertisement policies, etc] - whatever. The Google, Amazon, Microsoft, Facebook etc mess of rules designed to make them more money, especially from adult advertising

[needspeed]

Your mainshaft bearing isn't a Harley upgrade. It's a modification that someone before you did. If it was done properly I think it should work adequately and I see no need to change it.

It's hard to find a needle bearing that works with the diameter of the mainshaft.

A stock mainshaft measures .991".
An inch series bearing for a 1 inch shaft would be too big.
A metric bearing for a 25mm shaft (.984") is too small.

There is a modification that some have done where the stock rollers are replaced with a 25mm I.D. ball bearing. In which case the shaft has to be ground smaller to fit.

It's possible that was done to your shaft too. If it doesn't measure .991" then that is the case.

If there are numbers on the bearing would you post them?

[Jaime1840]

Originally Posted by needspeed

Your mainshaft bearing isn't a Harley upgrade. It's a modification that someone before you did. If it was done properly I think it should work adequately and I see no need to change it.

It's hard to find a needle bearing that works with the diameter of the mainshaft.

A stock mainshaft measures .991".
An inch series bearing for a 1 inch shaft would be too big.
A metric bearing for a 25mm shaft (.984") is too small.

There is a modification that some have done where the stock rollers are replaced with a 25mm I.D. ball bearing. In which case the shaft has to be ground smaller to fit.

It's possible that was done to your shaft too. If it doesn't measure .991" then that is the case.

If there are numbers on the bearing would you post them?

Hey needspeed,

Thanks for the info,

I'm going to measure the shaft today and I will check if there's any numbers on the bearing and I will let you know.

Jaime

[Jaime1840]

Originally Posted by needspeed

Your mainshaft bearing isn't a Harley upgrade. It's a modification that someone before you did. If it was done properly I think it should work adequately and I see no need to change it.

It's hard to find a needle bearing that works with the diameter of the mainshaft.

A stock mainshaft measures .991".
An inch series bearing for a 1 inch shaft would be too big.
A metric bearing for a 25mm shaft (.984") is too small.

There is a modification that some have done where the stock rollers are replaced with a 25mm I.D. ball bearing. In which case the shaft has to be ground smaller to fit.

It's possible that was done to your shaft too. If it doesn't measure .991" then that is the case.

If there are numbers on the bearing would you post them?

Hey man,

The mainshaft has been grounded off, It measures .944" but I dont think it was done properly, it looks like it was done by hand with sand paper or something... surprisingly the bearing fits pretty good both in the shaft and in the case. I bought another transmission a while ago because the one that came with the bike was in very bad condition and it was more expensive to repair it than to buy a complete used one, my idea is to keep this bearing set up and machine the mainshaft of the new gearbox in a machine shop. What do you think? by the way there was no numbers on the bearing.

Here is some pictures:

https://postimg.cc/gallery/1RNfpKT

[ryder rick]

My calibrated eyeball micrometer says, That bearing does not look big enough to go on the top shaft....?

[needspeed]

I'm assuming the bearing you're using came with an outer and inner race.

The OD of the STOCK race is about 1.564". So if the steel insert in the case was bored any bigger than that to fit your bearing, it will be difficult to change back to the stock set up. Keeping what you have is probably the easiest thing to do.

I'm not a bearing expert but I don't think your bearing can handle the load that the stock rollers can, but I think that it's good enough.

Looks like the sprocket is what keeps the bearing from sliding out to the right. What do the mainshaft shims ride against? Is there a steel shoulder like stock?

Your bearing has an inner race so the surface finish of the shaft where it's turned down is not an issue, but it needs to run concentric with the shaft and be a reasonably close fit in the bearing. At the .944 diameter I doubt that all the case hardening is gone and that shouldn't matter either.

In post #16, Picture brng3 it looks like the roller cage is cracked.

[ryder rick]

I take that back, It does fit, it appears to have a inner race maybe there is also one in the outer position? Any numbers on anything?

[Jaime1840]

Originally Posted by needspeed

I'm assuming the bearing you're using came with an outer and inner race.

The OD of the STOCK race is about 1.564". So if the steel insert in the case was bored any bigger than that to fit your bearing, it will be difficult to change back to the stock set up. Keeping what you have is probably the easiest thing to do.

I'm not a bearing expert but I don't think your bearing can handle the load that the stock rollers can, but I think that it's good enough.

Looks like the sprocket is what keeps the bearing from sliding out to the right. What do the mainshaft shims ride against? Is there a steel shoulder like stock?

Your bearing has an inner race so the surface finish of the shaft where it's turned down is not an issue, but it needs to run concentric with the shaft and be a reasonably close fit in the bearing. At the .944 diameter I doubt that all the case hardening is gone and that shouldn't matter either.

In post #16, Picture brng3 it looks like the roller cage is cracked.

Hopefully I will have time to check everything this weekend! thanks