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-   -   Everyone Should Read This ... (correct assembly and break-in) (http://xlforum.net/forums/showthread.php?t=600260)

aswracing 9th September 2009 21:17

Everyone Should Read This ... (correct assembly and break-in)
 
... it drives home the point about correct assembly and break-in procedures. Great pictures too:

http://www.axtellsales.com/RonsDocs/...g%20report.pdf

Bottom line, you can do a lot of damage to your motor if you:

- Don't keep it clean on assembly.
- Let it get too hot, especially before the rings have seated
- Don't tune it right, resulting in excessive heat

Toadz 10th September 2009 00:21

I also believe that this is something everyone should read: http://www.mototuneusa.com/break_in_secrets.htm

It's how I break in my engines and I can honestly say I notice a huge difference in performance and reliability.

aswracing 10th September 2009 06:18

Personally I think that method is a formula for ring microwelding. It's absolutely foolish to hammer a motor before the rings seat, as the rings are only touching the cylinder wall in a few places. This concentrates the pressure in those places and causes localized heating, which is exactly what causes the damage described in the Hastings analysis. If you notice, proper break-in procedures are all about keeping the heat down; there's a good reason for that.

wandrur 10th September 2009 06:38

Quote:

Originally Posted by aswracing (Post 2158804)
Personally I think that method is a formula for ring microwelding. It's absolutely foolish to hammer a motor before the rings seat, as the rings are only touching the cylinder wall in a few places. This concentrates the pressure in those places and causes localized heating, which is exactly what causes the damage described in the Hastings analysis. If you notice, proper break-in procedures are all about keeping the heat down; there's a good reason for that.

I was thinking that, too, but I didn't have the technical wherewithal to be sure that what I thought I was thinking was indeed what was there.

Bob F 10th September 2009 11:39

I've always followed the Owner's Manual. My E-Glide has over 50,000 miles and doesn't use a drop of oil between 5,000 oil changes. Think I'll stay with MoCo on this.

Toadz 11th September 2009 20:22

Quote:

Originally Posted by aswracing (Post 2158804)
Personally I think that method is a formula for ring microwelding. It's absolutely foolish to hammer a motor before the rings seat, as the rings are only touching the cylinder wall in a few places. This concentrates the pressure in those places and causes localized heating, which is exactly what causes the damage described in the Hastings analysis. If you notice, proper break-in procedures are all about keeping the heat down; there's a good reason for that.

Yes you do have a point with heat but if your bike is properly tuned this will not be an issue. The rings need a high amount of cylinder pressure for proper seating otherwise they will not seat like you mentioned. You will not get this pressure from riding in the lower RPM which will cause the localized heating.

I broke my YFZ450 and my Harley in this way and both are strong runners and do not burn a drop of oil. My '05 YFZ has nikasil coated cylinders instead of sleeves and the manufacturer recommends rebuilding around 50-60 hours. I have at least 300 hours on it and it still runs like a champ. Stronger than any other stock 450 I've ridden.

Of course it is all up to the owner how they want to break in their engine. It's always going to be hard to accept someone telling you to ride your engine hard for break in when every manufacturer has been telling you otherwise for the past 100 years. I try and spread the word of this break in because it worked great for me and I've never been a believer in easy break ins. To each his own.

NRHS Sales 11th September 2009 20:31

Toadz,
Both your HD and your Yamaha have already had the heat cycles done to the engine before it was delivered to the dealer. That is probably why you have been lucky enough not to have welded your rings. I don't think you really understand the cause of micro-welding either. It is not from improper tuning. It is caused by high spots on the rings getting excessivley hot. No rings are perfect circles from the factory, they all have high spots. Until these high spots are worn away you need to baby them. If not you will get results like posted in the link Aaron provided.

If you use the method you posted above on a fresh engine you are just asking for problems and I doubt you would get any kind of warranty should you mess it up. I know on my kits you would not and it is very obvious when somebody does not break them in properly.

But what do I know? i just sell hundreds of cylinder and pistons kits every year.

DC in PHX 11th September 2009 20:45

I am no expert, no way, no how. But 2 1/2 years into my NRHS 1250 build I have had no motor issues following Dan's assembly/break-in advice.

I think this thread will provide endless entertainment!

:spank:buddies:gun:boxing:wifemad:headbang:headb

Whre the heck is the popcorn smiley??

DC

aswracing 11th September 2009 20:54

Quote:

Originally Posted by Toadz (Post 2161372)
Yes you do have a point with heat but if your bike is properly tuned this will not be an issue.

Nonsense. Neither the bores nor the rings are perfectly round when made. The ring has to carve the cylinder into it's shape. Until that happens, the ring is only touching the cylinder wall in a handful of places. Since the pressure is concentrated in those spots, they get real hot. Get them hot enough and they cause microwelding. This is a well-known and well-understood fact. It's the reason that virtually every manufacturer specifies a break-in procedure that's designed to minimize heat. They know that until the rings seat, the rings and pistons are very susceptible to damage from localized heating.

Quote:

The rings need a high amount of cylinder pressure for proper seating otherwise they will not seat like you mentioned.
Nonsense. The process of seating rings will be accelerated by higher pressures, but to claim that it won't happen without high pressures is just silly. If the proper cylinder wall finish is used, the rings will seat just fine. The only thing you really have to be careful of is to not let it get too hot until that happens. If you do, you run the very real risk of damaging rings and pistons. It happens all the time and it's a very well understood phenomena.

Quote:

You will not get this pressure from riding in the lower RPM which will cause the localized heating.
Nonsense. Running a motor gently minimizes heat. Hammering it makes it hot.

Quote:

I broke my YFZ450 and my Harley in this way and both are strong runners and do not burn a drop of oil.
Anecdotal evidence at microscopic sample sizes proves nothing. Manufacturers that ship thousands or hundreds of thousands of engines a year, and have full time professional engineers to perform failure analysis (see the Hastings report), have far more data than either of us, or than "motoman" for that matter, and they're also able to quantify it. Saying that something is a "strong runner" is hardly a quantification of anything.

Quote:

Stronger than any other stock 450 I've ridden.
Again, this is a microscopic sample size and a non-quantified result from a non-controlled experiment. Deriving a conclusion from it is silly.

Quote:

It's always going to be hard to accept someone telling you to ride your engine hard for break in when every manufacturer has been telling you otherwise for the past 100 years.
That's because it makes no sense, and the body of evidence overwhelmingly shows it to be false.

Quote:

I try and spread the word of this break in because it worked great for me and I've never been a believer in easy break ins. To each his own.
You're welcome to treat your stuff however you want and believe whatever internet charlatan you want, and you're also welcome to make whatever claims you want, it doesn't concern me. But people who see far far more engines than you or I do and perform detailed failure analysis as they did in that Hastings report are dealing with much more actual data and have far more credibility with me.

If anecdotal evidence carries so much weight with you, perhaps you should read this article as well, in particular page 2:

http://www.axtellsales.com/RonsDocs/Ring%20Seal.pdf

Anecdotal and a microscopic sample size for sure, but I know Ron well, I've been to his shop multiple times, and I saw the rings out of this motor personally. Ron sells thousands of cylinders and pistons and rings every year and deals with this stuff all day every day, it's his business. He's forgotten more about cylinders and pistons and rings than you or I or "motoman" will ever know. But of course, you're free to believe that you and "motoman" know better.

Kwest187 11th September 2009 23:28

If you yell at your bike and break it in like a unwanted child it'll become tough and and learn to fix itself...
or was that a Johnny Cash song?
Good report Aaron-think I'll keep with NRHS break in method (or manufacture method) or common method for break in...
I feel that the other method may yield a circumstance where my bike finds me at a bar and we end up in a fight in the mud and the blood and the beer-
-or at the very least has poor compression-


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