Recommendations for L series engine break in

[r0p0doe]

Very helpful information in here because I will be breaking in my LZ swap soon and wasn't sure how it should be done. Think this would be a great pinned thread...

[smoke]

It is a good one, because for once (and believe me it's somewhat rare) Someone knows how to break in a fresh engine (Mike). So many just baby them to death, many get away with it to an extent, but as someone who has pulled apart MANY engines, the ones that have been flogged a little from the start have a much better ring seal and it's actually visible. 

 

Here's a story for you. A number of years ago, I bought a Kawasaki KLX650R that looked almost new. An older guy bought it to use as a dirtbike to ride with his kid and from day one, it was pretty much ran at idle and just barely above. When I got it, I made it street legal to buzz around town on. Whenever I gave this thing a bunch of throttle, it would smoke like crazy. Then it would start to foul plugs with oil. I knew I was going to have to at lest put rings in it sooner or later. BUT, some buddies of mine asked me if I wanted to go on a pretty long ride with them through the desert of Easter Oregon. I really wanted to go, so I just packed a few extra plugs with my stuff and the next day, we headed out.

 

One of the first things I noticed is I was getting horrid mileage for a bike, like 32 mpg and we were not even riding hard. When we got to the top of the pass, we stopped for a rest and to stretch our legs. When it was time to go, my bike would not fire. Pulled the plug and it was covered in oil. Dropped in a new one and it fired right up. Now, when we go out to the straight open roads of the desert, these guys are on beemers, so they are riding between 90 and 100 mph. My poor little dualsport is just wrung out, like full throttle, laying down on the tank and the whole deal. I rode that bike at full throttle for like 70 miles. We stopped for fuel and I noticed my bike sounded different, I thought perhaps some of the stuffing had blown out the muffler. It had more of a 'pop' to its idle. We filled up and I was surprised that my bike fired right up. Later we stopped to get some food and I thought it would be a good time to change the plug. I pulled it out and it looked perfect. The bikes throttle response had become much better than before and really got with it pretty decent.

 

We camped for the night and in the morning, I headed back home and they kept going on their ride. My mpg on the way home had almost doubled. My opinion on what happened here is that I forced the rings to seal better. Ever since then, no more oil burning or fouled plugs. It was a bit of a slug when I got it, it's not now.

[smoke]

One other thing I would like to bring up because it's something I just did and it's fresh on my mind. I have this old aircooled VW 1600 in my shop. It held alright oil pressure, but the ring gap was just huge on it. Simple enough, as long as the cylinders are good, get some new rings, break the glaze and run it. So, I got a set of rings, set the gap right and just for the hell of it (mostly because it is so simple to pull the cylinders and pistons off a VW engine) I put the new rings in and did NOT break the glaze on the cylinder walls. Really just wanted to see what would happen more than anything.

 

So, I fire it up and of course, it smokes like a house a fire. I get it a little warm, jump in the car and just ran the snot out of it. When I first took off, you could not even see the road behind me for all the smoke, but I kept in it. I drove it 17 miles, most of it just full out, hard on the throttle and letting it pull. By the time I get back, not a bit of smoke. Compression test right where is should be on all four. Leak down is very low. The flogging sealed them up.

 

Don't read into this that I am suggesting anyone try this. Just that it goes further to prove the idea the rings need to have some pressure given to them to seat good.

[Robert]

Didnt read all the replies.....but here is how I do it.

 

 

After you started it and made sure all is correct, get on the road, put in a middle gear (2 or 3rd for manual or 1st for auto) start at lowest speed and give it full throttle until red line...let off the throttle but leave in gear letting engine decel until low speed. Full throttle again repeating about 10-15 times.

 

Only thing needing special break-in are rings. This laods them hard on accel and decel conditions

 

non-detergant oils for special uses only (racing, parrafin engines from the 60s, and engines from the stone ages.) Get a dirt cheap standard oil 5w30 and change it after 500 miles to a good oil.

 

 

 

Engine is ready to drive normally.

[Dalesun]

For an oil with zddp already in it Valvolen VR1 is my choice. Its fairly cheap at 5 bucks a quart here in Eugene, OR. Can be hard to find muti weight but napa usually has a few multi weight ones.