man I"m bored
 

Just rebuilt the top end on my Manco engine, but havent got it cranked yet. I havent had time to work on it yet this weekend. still trying to figure out why its not firing, but I was just wondering how many people really listen to the advice after building it, about running it for a tank of gas running it no more than 1/2 thrrottle then another tank for about 3/4 throttle. does anyone listen to this? just curious. Is there anyone human really that patient? lol zman

I try to take it easy as much as possible, but I'm guilty I admit. I do mash the gas pedal sometimes. (really short burst, and not uphill/heavy loads)

I never broke mine in. But I didnt have that advice at the time. I would have done it had I known. And whenever I get my 59mm bore I will do it right.

do you think it would make a difference and how?

The purpose of the break in is to give the new parts (that do not fit perfectly together) the opportunity to mold together. IE. you want the rings to mold to the cylinder wall. If you bust into it straight out you could actually score the cylinder wall to match the ring instead. Same with crank bearings, cam bearings and many other parts. It just gives everything a chance to set together.

I break motors in hard!! Thatts right I ride it hard. Never had a problem with any motor doing it this way. I know sounds cruel but it works for me. I don't baby it.... google it, (how do you break in a gy6 motor?) :)

Whaaaat?? There's a break in period????? :eek:

Reruns!!!
 

All I know is I put new rings in and didnt do a full "break in" to let it all "seat" and on the next trip out both buggy's are now smoking again! So I'm gonn:banghead:a do it again, but this time I will "baby" them, til I use up a tank, even if I have to let them set and idle for awhile!!!

This is a touchy subject for some people. Some break them in hard, while others baby it for the recommended amount of time or miles.

On my bike I tried the hard break in and must say, I think I hurt it a bit. When you are seating rings, there are only a couple spots on the rings that ride on the cylinder walls. So you get concentrated areas of heat which can lead to "micro welding".

Here's another pretty good read. You can choose which way you want to go

http://xlforum.net/vbportal/forums/s...t=microwelding

When I was in high school I rebuilt a small block chevy and was told to not take it over 2500 rpms for 50 miles. I didn't. But at 13 miles it blew a rod out the oil pan and into the road. I had to take a hammer to the rod to get it out of the pavement. From then on I have broke them in the way they were going to be used. New cars I drive easy until about 500 miles and then I get on them so that I know they will not let go if I need them.

My record is 2 engines and 3 trans blown up in a single week! Racing...

As a tech, I agree with rebuilds being broken in for a little while, then drive it like you normally would. For a factory built engine, give her hell, thats what they were meant for. I have often been yelled at in the shop by service managers, parts managers and even the general manger once about revving a freshly installed short block I just put in, my response was, if they didn't want it to do that, then they shouldn't have designed it to. Also, with my SV1000, I was told by a suzuki rep to ride it alternatively hard and easy in the first 300 miles to break into the electroplated cylinder, I have 18k hard ridden miles on that engine and she never gives me any trouble.

Well i hope i broke mine in right, cuz i have been beating the piss out of it on the trails when i go. Full bore up the muddy hills and anywhere else i can open her up. One thing did break this weekend though. The wire for my temp sensor on my Vapor. Not sure if it snapped from stress or burnt through it. Either way, enjoy the engine and drive it like you want. Not every engine breaks in or reacts the same.

Years ago you had a breakin period on a new vehicle whereas today you do not. This is due to the advance in cnc machinery and the added quality control. I have a speed shop near me who will take a fresh rebuild and dyno it wide open. This is due to the precise machine work done and parts used. The problem with our chinese buggies is that the parts we buy are not precise custom parts so a break-in is advised. Most will not do it and have no issues, howeve you take 2 fresh rebuilds using identicle parts in which one you break in and the other you don't. After about 20 hours on each you perform a compression check and find the engine broken in has 5-10psi more comp. as compared to the non broken engine. This results in more power, and longer engine life.

Many sport bike makers are still pushing the break in period, albeit, its only 400-600 miles most of the time, and some even have the ecm limited so you can't rev it over half throttle. When you hit the required mileage, you have to take it in to the dealer to reflash the ecm. I know the european bikes are still doing it, not sure on all the japanese though, I know suzuki does not. Still might go back to acceptable tolerances, since the japanese usually have super tight internal specs, and the quality shows.

I"m gonna try to be patient and break her in right, may get some of the kids to ride it first. lol

Aman Zman, when I put the next set in I'll baby it to the max! A smoking engine at the off road parks is embarassing!!!

Remember your motor will smoke during breakin period. Those are ur rings seating.

With fresh rings you should not see any visible smoke. One thing most do is to install the piston and rings without checking the ring gap. Especially when installing a new bore the rings need to be gapped. Rule of thumb is .004" for each 1" of piston diameter. Many of the kits the rings will have less then .003" gap. Then when the engine gets hot the ring gap has closed causing ring bind which will lead to premature ware and or broken rings.


TOM

So is that hair do you're sporting Bear. :laugh2:

I always do three heat cycles on an engine when I rebuild it. Run it long enough to get to operating temp at varying throttle positions, then let it cool down. Repeat 2 times. Then the first tank of gas, take it a little easy. Change the oil and readjust the valves. After that, anything goes. Just from my experience, I have found that the oil rings tend to seat in better this way.

I agree break-in will get you 10-15 more PSI over not breaking it in.

Only half way!
 

Well "Toomany" I did the heat cycling process that you mentioned, as a mechanic friend of mine advised me of such, but I didn't "baby" it thru the first tank of gas! I believe that was my down fall! but my daughter and I had a great time riding and there was a definite improvement in performance! lesson learned! :buttkick:

Final thought; what works for some don't work for others. 3 ways to go about it and probably one best way... 1) run it hard 2) baby it 3) run it the way you would normally ride. I'll say #3. Would be the way to go, not hard not easy. Final answer. I believe that's syc answer and I'm going with that.. I normally run it hard, but maybe I've just been lucky.. no more going with #3...Eddie.

One of the break in theroys that I also go by is never keep a steady RPM during the break in period. Rather to vary the rpm up and down. The theroy behind this is that it will cause presuure to be put on the rings in one direction while accelerating, then put pressure on the ring in the opposite direction when decelerating.

The pressure changes are "supposed" to make the rings grab into the cylinder and break them in faster.

The only time that I has a ring failure was on a 4 stroke dirt bike. I heat cycled it and rode it in a field for a short time before going to the desert. Our first ride out, we climbed a pretty steap hill almost immediately after leaving camp. Let;s just say that after that, I never has mosquito problems. They couldn't see me to find me :banghead:

I take it easy for the first 10 min shut it off and check for leaks, cool it down and do it one more time then let it rip. The reason for me to take it easy is so the rings can wear into the cylinder do to the tight clearance and don't want to take a chance of getting it to hot the first run or if any thing is not right. On my dirt bike I do the same thing two 10 minuet heat cycles and then go for it.

Johhny 5,

Wear are you from? I noticed in one of your posts that you go to Gorman. Haven't been there in years. Do they have many trail closers, or is still pretty much wide open. We usually go to Searless Station out of Ridgecrest. I'm in Fresno

toomanytoys2, I live in lake forest and we haven't been to Gorman yet, we were going this weekend but they closed the park due to fire danger. We will try again in two weeks but we usually go to Ocotillo wells, but after late April it gets too hot.

Yeah, some folks get the snow, we get the heat. Its not much fun when its 110 degrees.

Hey Slezman "flat tops" are in style!!! bohyah

Yeeeeeaaaaahhhhh boyyyyyyyyyyyyyyy!!!!!!!!!!!