Snakeoil wrote:I have seen one specific situation involving syn oil as a break in oil on a vintage Brit bike. Bike was a Triumph T140 Bonneville. The engine builder was a dealer for 45 years, one heluva mechanic in my humble opinion based on the work I've seen him do. And I'm not talking just motorcycles. I talking vintage cars, tractors, steam engines, Walters FWD trucks, tracked vehicles, etc., etc.. He's in his 70's now and still going strong. Does a lot of Brit bike engine rebuilds. He's not one for urban legends or claims without facts either. I have so much confidence in his opinion that if he told me to run a mix of Suntan Oil and Crisco in my bikes, I'd probably do it... well maybe not.
I was in his shop and he had a T150 in there because it was very hard starting. I stuck around and helped him tear the top end off the bike because I was curious as to what we'd find. He had just rebuilt the engine the summer before and could not understand what was wrong with it. As we worked on this bike the subject of breaking in an engine and syn oils came up. He said that he's only had one engine in his entire career that smoked after he rebuilt it. The owner brought it back after about 500 or so miles and it was smoking. Lance is a really stand up guy and has no problem taking a second look at anything he does. I suspect this is the case because his work rarely, if ever, needs a second look. He said he pulled the engine apart and everything was perfect inside. But he said it looked like the engine had never run. This is when he told me that the owner insisted on putting syn oil in the bike from the outset. Lance said that was the only variable that was different from his normal Triumph twin rebuild process. When he put it back together, he said he did nothing to the engine except run a hone in it a few strokes and put a new set of rings on the pistons. But this time he put fossil oil in the engine and he said it never smoked again.
I realize this is only one datapoint. But Lance as an engine rebuilder said he will never put syn oil in a freshly rebuilt engine again. He has no problem with syn oil in an engine that is broken in. But no syn for break-in.
Now, to that point, one of the strong points of syn oil is film strength. So, if you slather all the bits with syn oil during assembly and then run it in with the same syn oil, one could argue that the film strength is so strong that it does not allow sufficient wear to take place to seat the rings. This falls in line with the mototune guy's theories about running them in hard, causing hard seating of the rings.
So, if it were me, I'd go with Lance's one-time experience and would not break in a freshly rebuilt engine with syn oil.
As for new engines in new bikes, they are run in at the factory. And if you believe the mototune guy, he says they redline every engine and hold it there, thus seating the rings right off the bat. So chances are, when you get the bike from the dealer, it's really already been broken in.
I know somebody is going to ask what the end of the story on the T150 was. Again, he could find nothing except the ring gap being outside of spec.. I asked if he does not check ring gap and he said he always does. But he admitted he might have gotten distracted. At the time, he thought that the .010 rings were stock size in a .010 box. He said he's seen that before. He called Hepolite and they said that they opened up the gap spec on their new rings and all the 0.010 rings will have that end gap. He put in new rings anyway and the bike fired right up and has run well since. He thinks it might have been a bad dose of gas due to it not being treated properly when the bike was put away for the winter.
I know, long story for a short question. But it's raining and I'm fresh out of projects at the moment.
Regarding Jensen's comments. If he meant the oil is thinner, I'm not sure that is the case. The 5W oil will get no thicker than 5W oil at freezing. It does not mean that the oil is the viscosity of 5 wt oil at room or operating temp. If you have not read that oil article I mentioned and for which I provided the link, I would strongly recommend it because it not only discusses the issue of which oil for air cooled bikes, but it also provides a great summary of the various properties of oil and what it means regarding application and how the oil performs.
regards,
Rob
30W Non-detergent - Or is there something better?
Well rain or not to much to look at for me. ...............lm
What, like from first startup (once the engine is warmed through, of course)? Now, I learned, four decades ago, that the best way to bed new rings is to rev the nuts off the engine from the get-go. I can't say that I'm 'experienced' at putting such a method into practice, as I'm not an engine builder. OK, I've done the deed on cars and bikes, but not for many years; hence my posting the question in the first place. I can't see that the machining high spots are going to thank me/us for ignoring them from the outset. It just goes against the principle of mechanical sympathy. But a set of rings and a hone, I can understand. Thanks for the reply and the anecdote, Rob; like I said, it does fall into line with past-learned legend.
Continued:
I just re-read the Break-In Secrets. It all falls into line with everything I learned in my formative biking years (when engineering tolerances weren't as close as they are today). It also falls into line with info gleaned from my ol' Mate Rob from Middlesbrough, UK. He's a guy who really knows his stuff (for a whippersnapper!) and he's worked on some of the closest-tolerance, highest revving -- short stroke V8s hitting 18K RPM -- engines for a few years now. The materials in our bikes aren't up to those sort of standards, but I'm gaining in confidence and becoming more comfortable with the thought of screwing a bollocks off my freshly-assembled engine! I always have worked my cars & bikes hard. Even my diesel cars & vans. And they've always performed pretty faultlessly. You know the scenario: the sales engineer's car is always the fastest on the road, especially in reverse!! I threw a rod once, on an old '70s Rover P6 that I owned, but that was an old car and I hated it..... I've never blown an engine on an 'owned from new' vehicle.
Hi,
A 5W-30. "W" means winter. In winter weather the 5W oil will flow like a 5W oil, and the 10W will flow like a 10W oil just until the engine warms up. In order to understand the differences one must first understand that the numerical values given to these various weight oils are strictly empirical numbers. In order to determine the differences between oils you have to look at the kinematic viscosity of each lubricant. The kinematic viscosity is essentially the amount of time, in centistokes, that it takes for a specified volume of the lubricant to flow through a fixed diameter orifice at a given temperature. That means that a 5W oil is more "liquid" then a 10 W oil, when cold, that's why I use 5W in winter and 10W in summer. Jensen assembly of Japanese motorcycles requires great peace of mind (Pirsig)
I agree, Jensen. I think it was an English thing in that previous post. The question is, does 5W oil at 32F degrees flow the same as 30 wt oil at 70F deg? And I believe the answer is a qualified yes. I imagine that there is a temp where 30 wt oil is the same viscosity as 5wt oil at 32F. So, a 5W-30 will probably be slightly less viscous than a 10W-30 oil at the same temp. But, I don't think it will ever fall below the min viscosity requirement of a 30 wt oil at operating temp or 212 F. The difference between the two are the additives that allow it to have the broader range and these additives are what break down. So, the broader range oil loses it's high temp properties faster than the narrower range oil because it is more reliant on the additives. This is something I've read in a number of technical papers on oil. A common recommendation is to always go with the narrowest viscosity range that your ambient will tolerate. The narrower range oil has a longer life expectancy. You could test the multigrades by making a simple gravity fed rig. A funnel with a piece of small ID tubing as the outlet, a catch beaker to determine a measured quantity of oil thru the orifice and a stop watch is all you need. Put the oil in the freezer for the cold test and use room temperature oil for the warm test. I would just be interested in how the multi flows compared to straight wt oil at room temp, say 70F. I'd be willing to bet that they flow almost the same with the multi a little thinner. But it would never be below the 30wt flow rate at 212F. regards, Rob
Shouldn't the gradual removal of zddp in auto and even diesel oils in recent years be a concern?
It seems that now it is only available in motorcyle oils and a handful of specialty oils. I am not that familar with the 305 engines, but with my British and Jap bikes, I now stick to strickly to motorcycle oils because of that issue.
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