• Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

  • 2 Stroke Husqvarna Motorcycles Made In Austria - About 2014 & Newer
     TE = 2st Enduro & TC = 2st Cross

TE/TC My One Fiddy

I also refilled with Evans Waterless using their Flush first to remove the old coolant.
This should complete my engine rebuild and modifications, hopefully the snow will be melting soon and I can test everything out.





007.JPG 008.JPG
 
John Bunker said:
Some might find this interesting.
I had Line-2-Line apply their APC (Slick +) to the piston.
They build up this coating on the skirt to an almost interference fit to the cylinder bore.
You then slowly break-in the piston, wearing down the coating until she runs normal.
I also had them apply their “Thermal Barrier” a ceramic coating to the piston top.

More information can be found on their web site.
https://www.line2linecoatings.com/





View attachment 87264 View attachment 87265
Click to expand...

that's kinda interesting. I wonder if you could use it to recondition badly scored piston skirts (like on hard-to-find pistons).

I'd be changing the oil a lot on break-in on a 4-stroke.
 
Very interesting.
So what sort of premature wear does break in, and constant skirt rub do to the cylinder walls?
Or does it minimize that because of the reduced slap?

Also, what happens to the worn out product from break in?
Any potential engine damage from that floating around?

With the thermal coating on top, were you just looking to reduce heat?

What do they charge for those services?
 
NH-JP said:
Very interesting.
So what sort of premature wear does break in, and constant skirt rub do to the cylinder walls?
Or does it minimize that because of the reduced slap?

Also, what happens to the worn out product from break in?
Any potential engine damage from that floating around?

With the thermal coating on top, were you just looking to reduce heat?

What do they charge for those services?
Click to expand...

When things are put together correctly with the right clearances nothing rubs or wears but rather rides on a film of oil. The break in heat cycles are partly to let parts that have never run together heat up and cool down (expand and contract) a couple times without a load on the engine so that any places that have pressure points can smooth themselves out without galling. After new parts are bolted together and go through several heat cycles they become more stabilized. Things go bad quickly when the film of oil breaks down and metal rubs metal or when and engine is cold started nothing has expanded to it's operating clearance and has the chance to bang around and breach the film of oil that separates it from metal to metal. Too much clearance causes banging around and too little causes excess friction and the breakdown of the oil film. A piston is oval when cold and becomes more round when hot. If it gets too hot it goes out of round and puts pressure, usually on the sides of the bridge and begins to gall against the cylinder wall. Dirt and debris will easily break through the oil barrier and cause wear like sandpaper or in extreme circumstances failure from friction. When assembling and engine cleanliness and coating parts with assembly lube is extremely important, otherwise damage occurs before you get through the first ride. Wear is going to happen because air filters don't filter everything and carbon is formed when fuel and oil is burned and micro pieces of carbon wander around rubbing on parts it's like micro sandpaper wearing down parts over time until the clearances get too big and parts start banging around until you either replace it or it fails.

Some coatings are thermal to retain or dissipate heat. Heat creates horsepower but too much heat causes failure. Ceramic retains heat better than aluminum. Some coatings are applied to reduce friction or carbon build up.

I hope you find my reply helpful, it's a general explanation to an extremely complicated subject... unless you're a tech nerd you probably fell asleep in the middle of the first paragraph.
 
NH-JP,

The coating does not really rub off, more likes it smoothes out and that’s along a vertical patch near the bottom of the skirt 90 degrees from the wrist pin.
There isn’t any “potential engine damage from that floating around”.

The thermal coating’s main purpose is to reflect heat away from the piston crown.

They charged $67 for the two coatings to my piston.

Other services would of course be priced accordingly.



Pretty much all technical info can be found on their web page.
 
Thanks for the explanation.
Didn’t fall asleep reading it, just read slowly so my feeble mind could attempt to comprehend it! Ha ha!

It makes sense.
Would you expect longer life for that piston and ring set up, or only additional protection from failure?
Just curious.
 
NH-JP,

I’m hoping for both, protection and longevity of the piston and rings, but the silicon carbide Nikasil bore shouldn’t wear much either way.

This is the first time I’ve used this coating product so time will tell.
 
This is the stock piston after one year (578 miles) of riding.
Its surface is showing signs of wear.
I won’t know how the Line-2-Line will compare until next year’s tear down.


P1060515.JPG
 
I am truly blessed to have my wife share my love of dirt bikes.
Luckily we both ride 150 Huskys, sure makes it easier when it’s wrenching time.
I’ll be doing mostly the same changes to her bike.


P1060558.JPG
 
I tried to get my wife involved as well.
She has absolutely no interest! :(

Which is fine. She is understanding enough to still allow me to have my thing.
She gets out with her friends all the time as well. It works for both of us. Still having 2 boys at home with their own sporting needs sometimes makes it a challenge!

Last year I raced a full hare scramble series, 14 races. That cut down on my overall seat time actually.
Instead of going out for a 50 to 100 mile trail ride, I was only getting the race distance in on a weekend.
So, just checked my ODO for last season.....2542.

I am lucky to run my own business. So a couple of mornings each week I start work a little late so I can get a 35 mile training run in.
 
I think last year was more like 3200 or 3300.
My rides usually have some road burn mixed in. It is the only way to get around in my area.
Ride a section of trail, connect to the next trail by a section of road, etc...
I am racing the enduro series this year to get more race miles in.
 
You must log in or register to reply here.
Back
Top