If you want to read the conversation that precipitated this modification, it starts here. It's quiet the slog.... 'bout 10 pages... and I'm not gonna re-hash it all here. The short and sweet of it is that I... and others... feel that the Mikes XS chain guide is unacceptable. Either twomanyxs1b's or 5twins suggested modifying the SR500 guide awhile back... so I decided to run with it. Here's the shot guide out of my SG.... As you can see, the rubber's separated from the guide. Now here's the SR500 guide from Boats.net... And here's the two combined to make a guide for the XS that I believe is better than the original design (more on that later)..... The guide in the background is the one from Mikes just for reference. So.... here's how you do it. The rubber on mine was already gone, so what's left is a C-channel we have to get rid of. I did that on a disk sander... A quick point here, make sure the table is square to the disk before you start. You only get one shot at this. Drill a hole in one end of the guide (I'll add the dimensions later if anyone wants them).... Flip it over and remove the spine from the back. I used a roloc disk to do this.... Now take the SR500 guide and cut off the 90deg mounting tabs. Actually, let me backtrack here.... I cut the mounting tabs, drilled and installed it... and it sat too tall. I had to take it apart and completely remove the mounts. Each one is held in place with two spot welds. I used a cutoff wheel to grind the welds off.... Go slow!!! If it gets too hot, the rubber might delaminate. Don't let it get too hot to the touch. Once the tabs are gone, flip it over and use a hole punch to remove the rubber where the holes go.... You can get a set of these punches from Harbor Freight for less that twenty bucks. They're great for making gaskets and such. The rubber on the SR guide is much too hard to punch through so I chucked it up in a drill press and used it like a drill bit.... Once it cuts to the metal base, use an exacto knife to remove the rubber from the hole. Do this on both sides of the new guide. Flip it over and drill holes in each end.... Now flip it back over and countersink the holes with a 100deg. countersink... Lay the new guide on top of the old and mark then drill the hole for the other end, then grind the spine off that side. To fasten them together I used Hi-loks. They're shear type, so the heads smaller than your average countersunk screw. Boeing uses these to build their wing spars. They have incredible shear strength... And there you have it.... an XS cam chain guide with a $25 replaceable rubber rub strip.... Pertinent info. Hi Lok: Part number is HL41-6-2 (or HL19-6-2 if you can find em'. I think the 41's superseded em') They can be sourced here. The damn things are $3.68 each. I've got a handful of them. So if anyone wants some, I'll let you have 4 of them for the cost of shipping.... 'till they're gone. PM me if interested. If anybody finds them cheaper, gimmie a link and I'll put it up here. Nut: Part number is MS21042-L3 It's self locking so no locktite is required. They can be sourced here. 36 cents a piece. I usually order in batches of a 100, but I'm almost out right now. When I order more, I'll include 4 with the Hi Loks. Till then, you're on your own. Yamaha SR500 Guide: Part Number is 583-12231-00-00 It can be sourced here. It's $24.38. 100deg. Countersink: Unless you're in aviation, you might not have one of these. You can get them here. You want the #12 at $8.90 each. Hole size: .190" Hole Punch: 5/16" Sand down old guide to these dimensions +/- .01" Drills holes in both ends Note: The SR500 guide is about a half an inch shorter than the old guide. I just centered mine on the old one. Note 2: DISCLAIMER.... I haven't installed mine yet 'cause I'm not to that point on assembly. I can't guarantee that it fits...yet. I'll update this when it's in. DISCLAIMER 2... Use at your own risk. I take no responsibility for what you do to your motor. Edit 8/7/18: Guide is installed. It fit without further modification.