Ricoh pin - what is it and why the need to remove?

GerryL · 06-02-2009, 09:40 AM

Ok, I have read this time and time again but have no clue as to exactly what this is.

I know it's a pin same as the contacts on the AF lens (from what I read) but where is it exactly in the lens,

and what is it exactly for that it would need this pin when it usually just gets the lens stuck on the camera.
If one removes it (..if I just know what to look for or where exactly is its position on the lens), would it not affect the performance of the lens?
I think this will help us newbies a lot and not go through the agony of finding out for ourselves first hand if a lens gets stuck on the body, if we where aware of what to look for and what to do.
Can anybody help with this?

GerryL · 06-02-2009, 09:42 AM

Oh..and how does one go about removing it anyway?

GerryL · 06-02-2009, 11:29 AM

Well, as I googled, so that I will be spared from this awful experience (so it doesn't happen to me), I chance upon a useful site that tells you what exactly this is and how to remove it.
It's a good thing I found this 'coz I didn't realize that I actually bought a lens that had the "KR" mount or markings on it.
It's agood thing I haven't fitted it on my K100D super yet as it has yet to be delivered.

Anyway, for those of you who might have this problem or to avoid it, here is the link to the site: theatre of noise: Ricoh Lenses On Pentax Cameras -- The Ricoh Pin Fix

stevebrot · 06-02-2009, 12:27 PM - **1 Like**

Glad you found your solution. Even more glad that you did not experience "Ricoh Pin Lock" on your camera.

For the benefit of the casual browser, here is the executive summary of the "Ricoh Pin" issue:

The infamous "pin" is found on lenses made to fit the Ricoh programmed exposure cameras
These lenses have a "P" on the aperture ring and include Ricoh's Rikenon-P series as well as third party lenses where the mount is marked with "K-R", "PK/R", or something similar
The pin is located such that it will drop into the AF drive gear on your Pentax dSLR when attempt is made to mount
Once engaged with the gear slot the lens will be extremely difficult to remove

The links posted above show the pin in all its glory.

A few additional notes:

The "spring-loaded ball" variant of the pin is less problematic
Rikenon lenses other than the "P" series (Rikenon, XR Rikenon) are not affected and are perfectly safe

Steve

GerryL · 06-03-2009, 08:15 AM

Yes, I found out that I didn't have the "spring-ball" type and it was more of the "brass pin" type.
I didn't actually remove it but just took it out and ground it to a level that the point of the pin was no longer long enough to stick out of its hole.
Then I replaced the pin back 'coz I actually didn't want an empty hole where some foreign matter might get lodged in.
So, the hole is still plugged by the pin but no longer sticking out.
It is now below the level of the mount itself.

Mission accomplished!

Sew-Classic · 08-22-2009, 07:08 AM

FWIW, I just dicover that my Sears Lens has this same pin. fortunately I found out before it got stuck on my DSLR.

This is great info and that link mde the modification super easy!

GerryL · 08-22-2009, 02:22 PM

Originally posted by Sew-Classic

FWIW, I just dicover that my Sears Lens has this same pin. fortunately I found out before it got stuck on my DSLR.

This is great info and that link mde the modification super easy!

That's good to hear as when I started I didn't have a clue as to where or what it was.
It was a good thing I just kept on hearing and reading about it but no real explanation.
I caught it in time though as I finally bought lenses that mostly had the Ricoh pin!
All my lenses that have these, I have disabled.
I didn't take them out, I just took the pin out to grind it a bit then returned it into its hole so the hole still would have a plug in it but not protruding enough that it won't get stuck in the camera screw drive.

photolady95 · 02-10-2010, 02:47 PM

Hate to bring an older thread to life, but I have a Rikenon P Ricoh 50mm 1:2 that I would love to use on my K100D but was told about not using it on this camera. Then I was told about or read about removing the offending pin. My lens only has one pin showing. Is this the same thing?

Here is a photo of the pin on my lens.

Sorry it's a bit out of focus.

JeffJS · 02-10-2010, 02:58 PM

Here's one thread that people report lenses having the pin

Here's another on how to remove it. Not too difficult for even the least mechanically inclined. Just keep all your screws in a row (so to speak).

photolady95 · 02-10-2010, 03:26 PM

Thanks Jeff. I'm pretty good with mechanics, I build and repair computers.

The links are ok but I used the on posted by GerryL in post #3 before I asked the question. So I knew how to remove the pin just didn't know if my lens has the same problem. It also lists other lenses with the same problem. I have a Sears 135mm f2.8 Macro but I've not had any problems with this lens on my K100D.

So, later tonight, I'll get my screwdriver and take this apart and remove that pin.

photolady95 · 02-10-2010, 04:03 PM

Did not work. I removed the pin per the instructions but now the lens won't even turn so I can mount it. Must be something else causing this problem.

JeffJS · 02-10-2010, 04:13 PM

Originally posted by photolady

Did not work. I removed the pin per the instructions but now the lens won't even turn so I can mount it. Must be something else causing this problem.

Then the flange near the aperture arm (top right of your photo) needs to be ground down. That's the 'other' issue with these types of lenses.

photolady95 · 02-10-2010, 04:51 PM

Okay. I was thinking that might be another problem. I have a dremel so that shouldn't be too hard to accomplish. Thanks again.

JeffJS · 02-10-2010, 08:04 PM

Originally posted by JeffJS

Then the flange near the aperture arm (top right of your photo) needs to be ground down. That's the 'other' issue with these types of lenses.

Originally posted by photolady

Okay. I was thinking that might be another problem. I have a dremel so that shouldn't be too hard to accomplish. Thanks again.

Some say you can grind it all the way off but I would use one of my lenses that works, as a guide.

Hope I haven't just told you how to destroy your lens..

Good luck.

**Just1MoreDave** · 02-10-2010, 08:41 PM

Should be able to remove the whole light shield by taking out the inner black screws, then see if it mounts. If so, that was the problem and you can modify the shield. If not, something else is the issue, possibly something bent. Does it mount to either film camera?

06-02-2009, 09:40 AM	#1
GerryL Veteran Member Join Date: Jan 2009 Location: CA Posts: 2,731	Ricoh pin - what is it and why the need to remove? Ok, I have read this time and time again but have no clue as to exactly what this is. I know it's a pin same as the contacts on the AF lens (from what I read) but where is it exactly in the lens, and what is it exactly for that it would need this pin when it usually just gets the lens stuck on the camera. If one removes it (..if I just know what to look for or where exactly is its position on the lens), would it not affect the performance of the lens? I think this will help us newbies a lot and not go through the agony of finding out for ourselves first hand if a lens gets stuck on the body, if we where aware of what to look for and what to do. Can anybody help with this?

06-02-2009, 12:27 PM - 1 Like	#4
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Glad you found your solution. Even more glad that you did not experience "Ricoh Pin Lock" on your camera. For the benefit of the casual browser, here is the executive summary of the "Ricoh Pin" issue: The infamous "pin" is found on lenses made to fit the Ricoh programmed exposure cameras These lenses have a "P" on the aperture ring and include Ricoh's Rikenon-P series as well as third party lenses where the mount is marked with "K-R", "PK/R", or something similar The pin is located such that it will drop into the AF drive gear on your Pentax dSLR when attempt is made to mount Once engaged with the gear slot the lens will be extremely difficult to remove The links posted above show the pin in all its glory. A few additional notes: The "spring-loaded ball" variant of the pin is less problematic Rikenon lenses other than the "P" series (Rikenon, XR Rikenon) are not affected and are perfectly safe Steve

02-10-2010, 03:26 PM	#10
photolady95 Otis Memorial Pentaxian Join Date: May 2009 Location: Cruising the forum watching his back Photos: Gallery \| Albums Posts: 12,712	Thanks Jeff. I'm pretty good with mechanics, I build and repair computers. The links are ok but I used the on posted by GerryL in post #3 before I asked the question. So I knew how to remove the pin just didn't know if my lens has the same problem. It also lists other lenses with the same problem. I have a Sears 135mm f2.8 Macro but I've not had any problems with this lens on my K100D. So, later tonight, I'll get my screwdriver and take this apart and remove that pin. Last edited by photolady95; 02-10-2010 at 03:33 PM.

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06-02-2009, 09:42 AM	#2
GerryL Veteran Member Join Date: Jan 2009 Location: CA Posts: 2,731 Original Poster	Oh..and how does one go about removing it anyway?

06-02-2009, 11:29 AM	#3
GerryL Veteran Member Join Date: Jan 2009 Location: CA Posts: 2,731 Original Poster	Well, as I googled, so that I will be spared from this awful experience (so it doesn't happen to me), I chance upon a useful site that tells you what exactly this is and how to remove it. It's a good thing I found this 'coz I didn't realize that I actually bought a lens that had the "KR" mount or markings on it. It's agood thing I haven't fitted it on my K100D super yet as it has yet to be delivered. Anyway, for those of you who might have this problem or to avoid it, here is the link to the site: theatre of noise: Ricoh Lenses On Pentax Cameras -- The Ricoh Pin Fix

06-03-2009, 08:15 AM	#5
GerryL Veteran Member Join Date: Jan 2009 Location: CA Posts: 2,731 Original Poster	Yes, I found out that I didn't have the "spring-ball" type and it was more of the "brass pin" type. I didn't actually remove it but just took it out and ground it to a level that the point of the pin was no longer long enough to stick out of its hole. Then I replaced the pin back 'coz I actually didn't want an empty hole where some foreign matter might get lodged in. So, the hole is still plugged by the pin but no longer sticking out. It is now below the level of the mount itself. Mission accomplished!

08-22-2009, 07:08 AM	#6
Sew-Classic Senior Member Join Date: Jun 2009 Location: Ohio, USA Photos: Gallery Posts: 238	FWIW, I just dicover that my Sears Lens has this same pin. fortunately I found out before it got stuck on my DSLR. This is great info and that link mde the modification super easy!

08-22-2009, 02:22 PM	#7
GerryL Veteran Member Join Date: Jan 2009 Location: CA Posts: 2,731 Original Poster	Originally posted by Sew-Classic FWIW, I just dicover that my Sears Lens has this same pin. fortunately I found out before it got stuck on my DSLR. This is great info and that link mde the modification super easy! That's good to hear as when I started I didn't have a clue as to where or what it was. It was a good thing I just kept on hearing and reading about it but no real explanation. I caught it in time though as I finally bought lenses that mostly had the Ricoh pin! All my lenses that have these, I have disabled. I didn't take them out, I just took the pin out to grind it a bit then returned it into its hole so the hole still would have a plug in it but not protruding enough that it won't get stuck in the camera screw drive.

02-10-2010, 02:47 PM	#8
photolady95 Otis Memorial Pentaxian Join Date: May 2009 Location: Cruising the forum watching his back Photos: Gallery \| Albums Posts: 12,712	Hate to bring an older thread to life, but I have a Rikenon P Ricoh 50mm 1:2 that I would love to use on my K100D but was told about not using it on this camera. Then I was told about or read about removing the offending pin. My lens only has one pin showing. Is this the same thing? Here is a photo of the pin on my lens. Sorry it's a bit out of focus.

02-10-2010, 02:58 PM	#9
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	Here's one thread that people report lenses having the pin Here's another on how to remove it. Not too difficult for even the least mechanically inclined. Just keep all your screws in a row (so to speak).

02-10-2010, 04:03 PM	#11
photolady95 Otis Memorial Pentaxian Join Date: May 2009 Location: Cruising the forum watching his back Photos: Gallery \| Albums Posts: 12,712	Did not work. I removed the pin per the instructions but now the lens won't even turn so I can mount it. Must be something else causing this problem.

02-10-2010, 04:13 PM	#12
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	Originally posted by photolady Did not work. I removed the pin per the instructions but now the lens won't even turn so I can mount it. Must be something else causing this problem. Then the flange near the aperture arm (top right of your photo) needs to be ground down. That's the 'other' issue with these types of lenses.

02-10-2010, 04:51 PM	#13
photolady95 Otis Memorial Pentaxian Join Date: May 2009 Location: Cruising the forum watching his back Photos: Gallery \| Albums Posts: 12,712	Okay. I was thinking that might be another problem. I have a dremel so that shouldn't be too hard to accomplish. Thanks again.

02-10-2010, 08:04 PM	#14
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	Originally posted by JeffJS Then the flange near the aperture arm (top right of your photo) needs to be ground down. That's the 'other' issue with these types of lenses. Originally posted by photolady Okay. I was thinking that might be another problem. I have a dremel so that shouldn't be too hard to accomplish. Thanks again. Some say you can grind it all the way off but I would use one of my lenses that works, as a guide. Hope I haven't just told you how to destroy your lens.. Good luck.

02-10-2010, 08:41 PM	#15
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	Should be able to remove the whole light shield by taking out the inner black screws, then see if it mounts. If so, that was the problem and you can modify the shield. If not, something else is the issue, possibly something bent. Does it mount to either film camera?