Break in mileage

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Skip
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Break in mileage

#1

Post by Skip » Sun Jul 09, 2006 1:54 pm

Ok guys...I have read and heard several different opinions, from 100 miles to 2000 miles...what kind of mileage do you guys do for a proper break in on a new top end.....Thanks......Skip



Cotten
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Re: Break in mileage

#2

Post by Cotten » Sun Jul 09, 2006 4:12 pm

Skip!

Break-in ain'what it used to be.
Modern rings such as Hastings are manufactured to be exact from revolution number one. If there is any 'mating' at all, they are damaged.
And since coatings are now standard on valvestems, we hope for zero break-in on those as well.
So any wear-mating or self-burnishing of moving parts has been reduced to the rest of the valve train. If you have fresh rocker blocks, or tappets and bores, they may not fully limber up for as much as 8000 miles.
The one phenomenon of break-in that concerns me most is where the valve faces "beat in" the valve seats to mate.
Freshly cut seats and faces make a distinct noise that goes away after a while. The time it takes varies with spring pressures, cam, combustion temperatures, valve and seat materials, and more other variables than I can type.
Whether breaking in a top end or a complete motor, the same dogma applies:

- Keep the lube fresh and clean,
- Keep the temperatures down,
- and vary your RPM as much as possible, without over-revving or lugging.

Most riders find it hardest to avoid lugging, as many ride that way much of the time. Tall sprockets do not benefit the break-in procedure!

....Cotten

Skip
Posts: 231
Joined: Mon Apr 26, 2004 11:18 pm
Bikes: 48 pan
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Location: WV

Re: Break in mileage

#3

Post by Skip » Mon Jul 10, 2006 4:12 am

Thanks...finally put about 100 miles on it yesterday...going between 0-35 on the first 50.....then up to 45 on the last...think I may put it under a little more stress over the next few days taking it up to 60 or so....Thanks again.....Skip

1950bobber

Re: Break in mileage

#4

Post by 1950bobber » Mon Jul 10, 2006 10:54 am

I'll make no contention with Cotten's advice...he has proven to know much more than I...having said that, I break my motors in by keeping the revs OVER 2000 ALL THE TIME DURING BRAKE-IN and that INCLUDES TAKE-OFFS from zero...for whatever you want to use for a mileage-ometer! The reason is as Cotton says...DO NOT LUG THAT MOTOR!!! You want that piston to go up and down nicely and WITH NO WOBBLE...lugging can produce the "wobble"...The next thing is again, DO NOT OVERHEAT IT! This means, just as you are doing Skip, vary the speed, ride short intervals...keep the temp down...If you live down South, ride the early morning hours and late evening when it is still cooler out....I then AVOID HILLS for XXX amount of miles...you fill in the mileage-ometer.
Hope this little bit helps...Good luck Skip...good to hear you're back on the road!

Jim

Skip
Posts: 231
Joined: Mon Apr 26, 2004 11:18 pm
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Location: WV

Re: Break in mileage

#5

Post by Skip » Wed Jul 12, 2006 2:03 am

Thanks 1950bobber...It's amazing how little you care about the mundane things in life when the Pan is on the road again...my main concern is the lugging from take off...the Linkert I put back on is taking a little getting used to...just as the accellerator pump was on it's replacement several years ago...I'll try that 2000 rpm take off...what worries me is the heat factor...it did get pretty hot...about a normal days riding worth of heat...but hot none the less...what are the ramifactions of too hot, and what is too hot...but on a brighter note it started first kick, hot or cold all day, and it hasn't done that in about 10 years...Thanks again Skip

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Re: Break in mileage

#6

Post by King » Wed Jul 12, 2006 7:04 am

Hi Skip

I too second Cotten's and Jims advice. I'll add what worked for me as prescribed by one of my more knowledgeable club bros.

* Run for around 20 minutes on the flat and vary RPMs between 1800-2800
* Shut down and allow to cool before starting again, no hot starting
* Use 93 octane (supposedly runs cooler) and MM Oil (I know I believe in Elves too)

I followed that routine for about 400 miles (10 hours on the tach) and then advanced to longer rides (~1 hr) over more varied terrain. At 19 hours I participated in a weekend of club rides for 280 miles (plus 120 miles coming and going) over some of the hilliest roads in Virginia and the bike ran faultlessly.
It's been a year now since the rebuild and I am very pleased with the performance. Many thanks to Smitty at Madison Motorcycles for such an excellent rebuild.
As Cotton mentioned I noticed some mild ticking in the heads over the first few hours as I suspect the valves were bedding in.

Enjoy that new motor.

King

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Re: Break in mileage

#7

Post by Pantony » Sat Jul 15, 2006 4:34 am

Skip carefull on lugging up those hills in the land of Chuck Yeager, they will create heat. I live on a lake and the road that goes around it has speeds at 25, 35, & 45mph. It's 13 miles a lap and I ran all my new motors in this way lap after lap and watch your oil temp. Get an oil temp gauge and check it every little while. Take a brake and as was aid let it cool down completely or ride it the next day after going over bolts (to make sure nothing came loose)

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