200h on the clock, and guess what....

[Tom250]

today i pulled off the topend of my ?13 300e, the bikes having around 200hours now and i thought it may be good to have a look to rings and piston.
piston looks good, little shiny parts, three minor scratches. last year the bike sucked some water because of the poorly and brainless constructed airbox so i guess this is what the scratches caused. measured the rings, upper 0,4, lower 0,3. guess its pretty in the range for its hours. the piston i will meaure next week, dont have a micrometer in my workshop, but i guess he will be in tolerance. cylinder also looks good in generally, two little scratch points from suckin water, a ride with the hone tool through it will fix that and will give back its crosscut.
im pretty impressed about that little wear in that engine, rod also dont have any play. ok i ride the bike smooth and take care of it, where i ride the bikes not getting much revs, no mx, but hey, anyway, after this much hours?
interesting how the cyliner is created, there is plenty of guiding surface for the piston, if you compare it with an pumpkin cylinder, there are more holes in than guiding survace. if the piston is in shape and the right measure, i bring em back on and i guess hes still good for another 100 hours....
by the way, spuish is 2,2mm.
well done gasser.....

[thejackrabbit]

what premix oil do you use?

[swazi_matt]

Just recently someone posted a link to slavens video where he says not to use a honing tool. News to me but made sense thought I should pass it on

[pscook]

Don't use a hone tool on Nikasil lined cylinders.

1. The stones are not the right grinding surface to interface with the nikasil
2. The stones will grab the ports and damage the cylinder

Use a diamond hone in the right size, or use red scotch brite to clean up the cylinder. You can also use a diluted muriatic acid (stone and grout cleaner) to wash the plating, just don't let it sit too long and clean it thoroughly when finished.

[Jakobi]

Show us some pics Pics make these threads and are great for others to comment on and for the newer tinkerers to get an idea of whats what

[Tom250]

pics i will post later.
well with the honetool. i saw this video from slavens, what confuses me, a hontool isnt good, but a sandpaper is??? his argument, a honetool leaves dust in the pores isnt really an argument, you clean the cylinder afterwords anyway with break cleaner wich washes the oil away including the peelingdust. and with a sandpaper i guess you havent any feel to get a right surface. from the experience of a friend wich runs a workshop in germany, he repairs any kind of bikes and bikeengines since 20 years, would say about a hundred engines a year, he always goes through a nicasil plated cylinder when putting a new piston in and never had any issues. i had a bike in 08, a husky wr250, wich i dived in dirty water and tryed to start up immediatly, in that cylinder was not just minor scratches, would say he was on the edge for a recoating, he went through with his honetool, put a new piston in and i rode that bike would say for at least another 100hours before i sold it then.
i understand that risk to break out the coating on the ports, but from my friends and my experience also, it never happend. its hard for me to imagine to brake out an edge from an port, then hone stones are a 100mm long and bring the pressure on a big and straight surface, and also that nicasil material is as hard as a stone. im up to learn more and change my opinion if its logic, currently this is my understanding of it.
in my bike i ran different oils, last year i used motul, mostly the 710, also sometimes the 800, both always in a 1:50 mix. this year i get a castol power1, bought a 60liter barrel.
sure my riding style is good for the engines life too, i mostly grunt around on trails and in the montains, there is no need and also no possibility to rev the bike.

[sweeper]

Cmon people!

No honing,boring,cutting,machining of any kind on a nikasil bore.

Not even a good old fashioned hillbilly drill operated cylinder cleaning device of any type.

If there is something in the cylinder you can't live with then use a white scotch brite.
Don't get crazy.Scratches don't mean jack on nikasil.As long as the bore is clean and true and free anything that can hang a ring.

That piston looks great.The rings after 200 hours have done a fine job of knocking down any high spots in there.

They don't make slightly over sized pistons for nikasil bores.

[Jakobi]

This topic has been done to death all over..

A cylinder needs to be honed to allow the rings to bed in properly. Thats why they are honed from the factory and a new cylinder will show heavy cross hatching.

As pscook has stated though, your standard old hone won't 'cut' Nikasil and is more likely to damage the cylinder or flake the coating from the port edges. Avoid it. In short, when you rebuild you want to deglaze the cylinder and remove any deposits from the surface. For me, a scotchbright pad and some carb cleaner works a treat and brings them up looking great. Phils other suggestions work well too, and scotchbright actually makes hones out of thir material to help speed up the process. http://www.enginehones.com/abrasivehones.html

If the crosshatching isn't visible still it means the cylinder is showing some wear, and the only way to know exactly how much is to spec it up with a bore gauge (which any engine builder would do anyway).

Oversized pistons are available A,B,C,D but the idea of honing out to the next size isn't feasable. In general the thickness of the nikasil plating is only around 0.1mm (0.004") so when its worn out, its time for a recoat.

[sweeper]

If dealing with a stock nikasil cylinder or a cylinder which has been replated back to its stock bore.
Hone-no
Scotchbrite-yes
Slightly oversized pistons-no

If you have a resleeved cylinder-see above post.

[Weird Rooster]

Originally Posted by Jakobi

In short, when you rebuild you want to deglaze the cylinder and remove any deposits from the surface. For me, a scotchbright pad and some carb cleaner works a treat and brings them up looking great. Phils other suggestions work well too, and scotchbright actually makes hones out of thir material to help speed up the process. http://www.enginehones.com/abrasivehones.html
.

Hey Jake. For us less experienced tinkerers, can you explain or provide a link to how you go about prepping the cylinder with a scotchbright pad? Do you use just a single pad by hand and which colour/grade do you use? Thanks