Break In-real story

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How strict do I have to be on the below 5000 rpm rule on the first 600 miles? I plan on having the valves checked on the 600 mi service. Advice? F4S 1+1 2002

-- Larry Nipon (vze277jp@verizon.net), May 27, 2002

Answers

My opinion is that manufacturers are way too conservative when it comes to break in. Think about race engines (which may or may not be comparable depending on manufacturing tolerances). Do you think they run a race engine for 500 miles before a race? Certainly not. The critical things are the valve seats and the rings. These are the things that are kind of a "form fit" where the 2 parts rub against each other until they are happy. The rest of the engine should pretty much be good to go.

I would stay under 5000 as a rule, but you can take it up past that once in a while, and I think any other engine builder would tell you the same. The manufacturer of course would not, because they want to blame any possible engine problem on you if they can. Infant mortality is rare these days, but very expensive in any case.

Does MV record engine speed over the first 500 miles on the computer? Don't know. It would be cool to find out...

-- Andy Ruhl (quadreverb@yahoo.com), May 27, 2002.


Hey Andy... you've been great on your responses. Thanks. To get a little granular, what are the worst-case downsides to going past the manufacturers's recommended limits during break-in?

-- Larry Nipon (vze277jp@verizon.net), May 27, 2002.

To tell the truth, I don't know. I don't know what exactly would be the difference between 5000 RPM and 10000 RPM after the bulk of the break in has occurred (which is probably the first 50 or 100 miles). What I do know is that the new engine oil has a hell of a lot more metal particles floating around in it, and when you load the engine more (as in, rev it higher and make it accelerate the bike harder), you are going to have more metal particles in the tight tolerances than you would otherwise have. Again, what's the difference between 5000 RPM and 10000 RPM in this respect? That's something for Kevin Cameron to answer. But I don't make it a habit of extended periods of high RPM running when the oil hasn't been changed in a new engine.

I changed the oil and filter in my R1 almost instantly after I bought it (I think within the first 50 miles or so) and then had the regular 600 mile service as well. My peace of mind was well served. I asked my dealer about doing this in the MV, and he kind of shrugged it off in a "You can but you don't have to" kind of way. Maybe oil filters are a whole lot better than I thought they were...

On my bike, I stayed pretty much under 6000 RPM for the first few hundred miles, then I took it up to redline maybe twice between there and 500 (when it got serviced), but I probably let it pull up to 8 or 9K more than a few times. It runs fine.

-- Andy Ruhl (quadreverb@yahoo.com), May 27, 2002.


I agree mostly with the comments of the other answer. Some other reflections about the first km on a new engine.

The clearances during manufacturing of motor parts are a lot smaller and with less deviation than 20 year ago. this means that the first km and the limit on the revs are not so critical any more. On the other hand, what is a lot more important, is that you should during the first 1000 km, almost permanently change from revs and from gear. In the opposite imaginable situation, where you would do one trip of 1000 km on the highway at 120 km/h and at 5000 rpm, then you will create a hammering effect on those metallic contact surface which exist in the very first beginning. So you will load locally the part too heavily during a too long period, but what is worse, after a while, the contact surface will look like a mirror, also under a microscope, without pores necessary for a good lubrification and this for a long time.

My suggestion : NEVER let the engine warm up without riding, but take off immediately. Respect the limits of the manufacturer as to the revs. Avoid to ride under 2000 rpm (lower oil pressure and risk of vibration). Ideal stay between 3000 and 5000 rpms. Accelarate smoothly and increase top revs after you 1000 km progressively. I advice also to replace the first oil fill after the first 1000 km, just to avoid metal chips wandering through the engine. If you want to do everything perfect, then use a special (thin) oil (see suppliers of lubricants) for the first 1000 km, but then follow carefully the oil level, because you will consume more than normally due to the viscosity.

Remember also that the life time of an engine depends on the use. In general the design is optimised for 3/4 of the max revs. This means that your engine will last the longest if you limit the revs in daily use to 3/4 orf the max.

-- patrick maes (patrick.maes@electrabel.com), May 29, 2002.


The worst thing that you can do during break-in is to keep the motor at a constant RPM. The rings will seat better if you place a slight load on the motor for brief periods reving up and down. Try and find some hilly terrain and not just cruise on level ground when working through the gears and reving between 2 - 5,000 RPM. When you go uphill this will place a load on the motor. Doing this in a medium to high gear at moderate RPM's will help to seat the rings better. Change the oil after 500 miles/750-800 km and then you can twist it on up.... Good Luck....FWB

-- F. William Baker (atelfwb@aol.com), May 29, 2002.


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