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Just purchased a new 2015 xt250 yamaha for work and trail ride's ... (not cafe!!!!! :eek: it's an Adv....)

Am wondering about the nicasil cylinder ring and gearbox break-in ..

What ARE the forum opinion's of proper breaking this in?

I 've always had iron sleeves with chrome and moly ring's in my fresh rebuilds (autos and early jetskis) so this nicasil is new to me..

Am trying to follow yamahas direction with this but am varying it somewhat..

I'm been running hots n'colds with loads applyed in gears up and down 2/3/4/5 (5 spd) , 10+ miles at a time while staying below 1/3 to 1/2 throttle,then pulling a quick blip intermitantly to clear the cylinder while its unloaded..
Have read that the best break in is done on the track with its intermitant loads and gear changes.. trying to simulate that as best as possible..
I will change the oil and filter at least twice before it hits the yamaha breakin period end at 1000 miles..
its got 50 miles,So I've a long way to go yet...
Opinions?????
 

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Piston rings made for nicasil ( or composite sleeve ) barrels are a special alloy that will lap into the shiny & hard surface. The rings do the work for you. The way you ride it will have little effect. Modern motors need virtually no running in.

Once you have done 300 miles, take it out for a good hard run on the flat or an hour or so, hitting redline through the gears and using a constant 80% of redline revs. This will guarantee a good piston ring seal and valve seat seal. Then get the motor serviced, and the valves adjusted to near max clearance ( not just checked ). Do that and you can forget about valve adjustment for a long - long time.

Honestly, babying motors does more harm that running them reasonably hard, like they were designed to do. Running high gears and low revs just make a bike run rich and coat the inside of the combustion chamber, and can contaminate the motor oil with unburnt gas.

Forget running in the gearbox. I doubt it could care less how you treat it. Smooth clutchless upchanges wear clutches far less that slipping the clutch with each change: strange but true. I'm not talking about clunky H-D and Ducati gearboxes BTW.

Don't bother ' warming up ' the bike. Just get it running off the choke and go. Far better to just ride it gently for a few miles than overheating it on the stand for no reason.

Personally I would not run synthetic oil for the first 1K miles or so. I'd run semi-synth from then onwards.

Danger, is my business.
 

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Urban legend has it that when the first Fireblades came out, the ones that the jouno's had (IE: the ones that were thrashed from the start) ended up making a few more HP than the ones that were babied. In other words, don't get hung up on trying to baby your bike for the first few hundred miles.

I was under the impression that Nikasil linings didn't need any break in? Wasn't that the point of having the coating on there - so it doesn't wear?
 

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I was told with my TZ250 to just do 3 full heat cycles "running temp to air temp" with no load to shrink the cast aluminum pistons and than just run the piss out of it, do follow your oil change scheduled.
 

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Here is the recommended break in for airhead beemers with nikasil linings:


1. The first 150 ride the bike taking it easy, checking the oil levels and not loading the rings. Check oil frequently.
2. Next 150 can be a little harder with mixed riding and somewhat harder acceleration. Check oil frequently.
3. At 250 to 300 miles, torque the heads and reset the valves.
4. From 250 to 500 you keep moving towards "Riding the bike the way you want to". Check oil frequently.
5. At 500 miles swap out the cheap break-in oil for the god stuff, service the bike and then ride it. By this time the bike won't be using so much oil but check it frequently anyway.
6. Break-in will be totally complete by about 5000 miles.

I say do what the manual tells you to do. If I remember anything from the nikasil problems Beemer and jag had with their cars in the 90's break-in is important.
 

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I'm going to take back what I said before about Nikasil linings not needing a break-in - apparently they need to wear off the nickel layer to get to the underneath silicon carbide coating which is the bit that doesn't wear out.

Nikasil is short for Nickel Silicon Carbide.
Silicon carbide is a very hard ceramic (much harder than steel) that can be dissolved in nickel. The nickel solution can then be electroplated onto the aluminium cylinder bore. The piston rings will then rub off the exposed nickel, leaving a very hard layer of silicon carbide to protect the aluminiumpiston from direct contact with the aluminium cylinder. With this setup, the engine tolerances can be much tighter for better performance. The cylinder must be re-plated after it is re-bored, but Nikasil is extremely durable, so the cylinder does not need to be reworked as often as an iron or chrome cylinder.
So, at the very least you'd be wanting to change your oil at the recommended break-in intervals to ensure the nickel plating is removed from the engine.

On another note a buddy of mine had one of those BMW 1150 Rocksters and the manual said to NEVER let the bike idle on the stand - start the bike and ride off immediately to avoid overheating.
 

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I've always been told that a new bike needs a break in. Or as my Dad used to tell me "New parts need time to get to know each other".
 
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