nklr- the question is answered!

[Norm Keller]

#ygrps-yiv-1664580060 blockquote.ygrps-yiv-1664580060cite {margin-left:5px;margin-right:0px;padding-left:10px;padding-right:0px;border-left:1px solid #cccccc;} #ygrps-yiv-1664580060 blockquote.ygrps-yiv-1664580060cite2 {margin-left:5px;margin-right:0px;padding-left:10px;padding-right:0px;border-left:1px solid #cccccc;margin-top:3px;padding-top:0px;} #ygrps-yiv-1664580060 .ygrps-yiv-1664580060plain pre, #ygrps-yiv-1664580060 .ygrps-yiv-1664580060plain tt {font-family:monospace;font-size:100%;font-weight:normal;font-style:normal;} #ygrps-yiv-1664580060 a img {border:0px;}#ygrps-yiv-1664580060 {font-family:Tahoma;font-size:12pt;} #ygrps-yiv-1664580060 .ygrps-yiv-1664580060plain pre, #ygrps-yiv-1664580060 .ygrps-yiv-1664580060plain tt {font-family:Tahoma;font-size:12pt;} Jeff, I expect that this will serve as inspiration for a Rotella pouring machine?       Simplicity is not the same as great engineering. You've dealt with engineers so I thought you could appreciate what happens when they apply themselves to improve an ancient piece of technology - say, the corkscrew..........     www.youtube.com/embed/wSuH9u0kvhU?rel=0  

[Norm Keller]

Martin Earle posted:

 

"snip Down to the thinnest shim available on the right exhaust valve unsnip. place a square of ~300 wet/dry paper on a piece of glass (make the grit side of the sandpaper wet) take that thin shim and hold it with your fingers on the wet/dry paper. make figure 8 movements with the shim against the paper/glass , = hand grinding the shim. Check every 10-20 rev for progress with a good caliper. It will get thinner, and you will be pleased. "

 

 

I often lap shims to obtain a size needed when the shops are closed and frequently wonder what is the minimum thickness from an alignment of loading and for maintaining sufficient shim strength. Obviously, some minimum thickness is required in order to avoid flexing of the shim with subsequent failure. This engineering is far above my pay grade but always niggling in the back of my mind and why I don't go below the minimum stock thickness. Having a shim break would be a huge disaster so being unable to predict, I'm conservative.

 

Can anyone offer any insight?

[libertyeagle]

Norm That was great, I downloaded it and shared it and it has created many laughs, totally worth it Michael

[Martin Earl]

Norm,YOu might be on to something there. grin. Could the previous poster please tell us what size is the thinnest shim you installed?Norm,Are you suggesting--Do you think the thinnest offered is the thinnest allowed? and if you reach that limit, it is time for a new valve, or valve/seat combination.I would be curious as to the overall length of the thin-shimmed valve. IRT to self grinding a shim--It 'appears' to me the shim is well supported across the valve stem end and spring, yet, I would defer to your judgment if you suggested the thinnest shim was the limit. If I had seen this earlier, I could have gone across town to the bmw dealer and asked them what the thinnest shim available/used on the F650; as well as the (I believe this is right) Ford Tarus SHO. Perhaps the previous poster would benefit form a new/used valve lapped into the 'thin-shim' location (when he does a 685 kit). Has anyone here installed new valve seats?m.1

On Sat, Apr 11, 2015 at 11:51 AM, 'Norm Keller' normkel32@... [DSN_KLR650] DSN_KLR650@yahoogroups.com> wrote: Martin Earle posted: "snip Down to the thinnest shim available on the right exhaust valve unsnip. place a square of ~300 wet/dry paper on a piece of glass (make the grit side of the sandpaper wet) take that thin shim and hold it with your fingers on the wet/dry paper. make figure 8 movements with the shim against the paper/glass , = hand grinding the shim. Check every 10-20 rev for progress with a good caliper. It will get thinner, and you will be pleased. " I often lap shims to obtain a size needed when the shops are closed and frequently wonder what is the minimum thickness from an alignment of loading and for maintaining sufficient shim strength. Obviously, some minimum thickness is required in order to avoid flexing of the shim with subsequent failure. This engineering is far above my pay grade but always niggling in the back of my mind and why I don't go below the minimum stock thickness. Having a shim break would be a huge disaster so being unable to predict, I'm conservative. Can anyone offer any insight?

[Norm Keller]

#ygrps-yiv-338930986 blockquote.ygrps-yiv-338930986cite {margin-left:5px;margin-right:0px;padding-left:10px;padding-right:0px;border-left:1px solid #cccccc;} #ygrps-yiv-338930986 blockquote.ygrps-yiv-338930986cite2 {margin-left:5px;margin-right:0px;padding-left:10px;padding-right:0px;border-left:1px solid #cccccc;margin-top:3px;padding-top:0px;} #ygrps-yiv-338930986 .ygrps-yiv-338930986plain pre, #ygrps-yiv-338930986 .ygrps-yiv-338930986plain tt {font-family:monospace;font-size:100%;font-weight:normal;font-style:normal;} #ygrps-yiv-338930986 a img {border:0px;}#ygrps-yiv-338930986 {font-family:Tahoma;font-size:12pt;} #ygrps-yiv-338930986 .ygrps-yiv-338930986plain pre, #ygrps-yiv-338930986 .ygrps-yiv-338930986plain tt {font-family:Tahoma;font-size:12pt;} I hoped that others might offer some feed back as to any experience with thinner shims than standard. The problem we encounter with many of these issues is that something comes apart without warning because we do not understand the whole picture. The thin shim is one risk but the other is that the combination of valve recession and valve stem stretch becomes a concern. Anyone who has had the head come off a valve will know exactly of what I speak. It usually destroys cylinder head, piston and often cylinder. As a valve stretches it necks out in the area above the tulip which affects both cross sectional area + metallurgy.   I can't support an argument that the thinnest shim offered is the limit for shim safe usage but given the consequences, that's where I draw the line. I did a KLR a few months ago which had reached the limit of shim on the exhausts. One was there and the other nearly. It seems far more preferable to replace the valves (and any seats necessary) rather than to take the risk, given the consequences.   I haven't replaced any KLR seats as am no longer equipped to do seats or guide machining however have had some bike ones replaced in the last few years. I'd be quite confident of doing so if had access to a Quickway or other boring system.       ------ Original Message ------ From: "Martin Earl" To: "DSN KLR650" DSN_KLR650@yahoogroups.com>; "Norm Keller" Sent: 2015-04-11 5:52:27 PM Subject: Re: [DSN_KLR650] Re: Fw: Engineers - you gotta love 'em.  

Norm, YOu might be on to something there. grin. Could the previous poster please tell us what size is the thinnest shim you installed? Norm, Are you suggesting-- Do you think the thinnest offered is the thinnest allowed?  and if you reach that limit, it is time for a new valve, or valve/seat combination. I would be curious as to the overall length of the thin-shimmed valve. IRT to self grinding a shim-- It 'appears' to me the shim is well supported across the valve stem end and spring, yet, I would defer to your judgment if you suggested the thinnest shim was the limit. If I had seen this earlier, I could have gone across town to the bmw dealer and asked them what the thinnest shim available/used on the F650; as well as the (I believe this is right) Ford Tarus SHO. Perhaps the previous poster would benefit form a new/used valve lapped into the 'thin-shim' location (when he does a 685 kit). Has anyone here installed new valve seats? m.1 On Sat, Apr 11, 2015 at 11:51 AM, 'Norm Keller' normkel32@... [DSN_KLR650] DSN_KLR650@yahoogroups.com> wrote: Martin Earle posted:   "snip Down to the thinnest shim available on the right exhaust valve unsnip. place a square of ~300 wet/dry paper on a piece of glass (make the grit side of the sandpaper wet) take that thin shim and hold it with your fingers on the wet/dry paper. make figure 8 movements with the shim against the paper/glass , = hand grinding the shim. Check every 10-20 rev for progress with a good caliper. It will get thinner, and you will be pleased. "     I often lap shims to obtain a size needed when the shops are closed and frequently wonder what is the minimum thickness from an alignment of loading and for maintaining sufficient shim strength. Obviously, some minimum thickness is required in order to avoid flexing of the shim with subsequent failure. This engineering is far above my pay grade but always niggling in the back of my mind and why I don't go below the minimum stock thickness. Having a shim break would be a huge disaster so being unable to predict, I'm conservative.   Can anyone offer any insight?