BlueRidgeBoy Posted January 12, 2006 Share Posted January 12, 2006 In June of 2005 I bought a used, one-owner, dealer-maintained 1998 RT with 36k on the odometer. The 36k service had already been performed by Morton’s. The bike had sat for the last couple of years with very few miles before I bought it. Based on this I decided to change all fluids a little early (early from a mileage point of view). So last week, at 40k, I changed the oil and sent a sample of the old oil to a lab. for analysis (see attached report). Everything looks good except it looks like I might be getting some air bypassing the air filter. I changed the filter last week when I changed the oil and it didn’t look bad. I don’t ride in exceptionally dusty areas. Here are the comments from the report (the scan is difficult to read): Universal averages show typical wear metals for an oil from this type of engine after about 5,200 miles run on the oil. Your oil was in use only 4,283 miles, and we found all wear around average levels and in the correct balance to show normal mechanical parts inside. Silicon was a bit high at 11 ppm and could indicate some excess dirt getting past the air filter so you may want to check that out. Oil filtration (see 0.3% level of insolubles) was good. This was BMW synthetic 15W/50 engine oil with no fuel, moisture or anti-freeze in it. Looks like you bought a nice one! Any thoughts on how air can leak in downstream of the filter or bypass the filter? All comments appreciated. I really enjoy this forum. Link to comment
Stan Walker Posted January 12, 2006 Share Posted January 12, 2006 Sounds like an K&N air filter. Switch back to stock. Stan Link to comment
BlueRidgeBoy Posted January 12, 2006 Author Share Posted January 12, 2006 Stan, No, everything on this bike (oils, filters, etc.) is OEM. Link to comment
BMW_Ken Posted January 12, 2006 Share Posted January 12, 2006 Matt, I would not be too concerned by this single analysis, especially since the oil had been in the bike for quite awhile. You replaced the air filter. If nothing is obviously wrong around the air box, I would just ride it and perhaps resample at your next oil change. I used Blackstone when I had my airplane and sampled every oil change. Generally you look for trends, rather than single readings, unless something spikes off the chart. That's my opinion, but I wouldn't worry at this point. Link to comment
John Dickens Posted January 12, 2006 Share Posted January 12, 2006 Does anyone know whether the RT has Nikasil bores and whether that would show up on an oil analysis? Link to comment
Rider1200RT Posted January 12, 2006 Share Posted January 12, 2006 To the best of my knowledge, and I could be wrong, all BMW's have nickasil bores. That's the reason it takes so long to 'break' them in. Link to comment
RFW Posted January 12, 2006 Share Posted January 12, 2006 Does anyone know whether the RT has Nikasil bores and whether that would show up on an oil analysis? This would not show up at all on an analysis. Nikasil is a matrix of nickel with silicon carbide embedded. Wear will not result in elemental silicon. Further, silicon carbide is extremely hard and extremely wear resistant, and is unlikely to be possible to show up in an analysis in any detectible quantity since the total amount of SiC is miniscule in the first place. The usual area where silicon comes from is piston skirts. Pistons are made from an Alu alloy with high silicon content. Wear on a piston skirt could result in silicon showing up in the oil. But I suggest there is no problem at all with this. It is easily possible to get obsessive without realizing it! Bob. Link to comment
RFW Posted January 12, 2006 Share Posted January 12, 2006 To the best of my knowledge, and I could be wrong, all BMW's have nickasil bores. That's the reason it takes so long to 'break' them in. The Nikasil layer is only microns thick. You don't "break it in" because it is so hard, it doesn't significantly wear. That's just as well, because if it DID wear enough to be broken in during this period, you'd wear right through it! Bob. Link to comment
4wheeldog Posted January 12, 2006 Share Posted January 12, 2006 I think I would just check the O rings and boots on the throttle bodies. If you don't find a source, just check it again next change. This amount of crud could just be the result of a dirty funnel or adding oil in a dust storm. Good Luck! Link to comment
Urban Surfer Posted January 13, 2006 Share Posted January 13, 2006 Scott and I put a fellow bike to sleep for a few years(changed the fluids). We found that the oil was really dirty, the suprizing thing was that one of the boots on the trottle bodies was loose and not fully egaged. There was lots of air getting past. The bike must have run like crap! Im convinced this was why the oil was so dirty. Link to comment
2wheelterry Posted January 13, 2006 Share Posted January 13, 2006 This amount of crud could just be the result of a dirty funnel or adding oil in a dust storm. Or some dirt in the sample bottle or ???. For work I review about a dozen of these a month. Believe it or not, often we get high silica from new oil, (bulk or 55 gallon). Our practice is to filter the new oil before putting into the machine. I am sure BMW oil would not include any contaminents. Link to comment
brennaman Posted January 14, 2006 Share Posted January 14, 2006 Blueridge, who did you have do your oil analysis, and what did it cost? Link to comment
Recommended Posts
Archived
This topic is now archived and is closed to further replies.