• 2 Stroke Husqvarna Motorcycles Made In Italy - About 1989 to 2014
     WR = 2st Enduro & CR = 2st Cross

  • 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 The previous version was outdated and no longer supported.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!

250-500cc Another Piston Thread

I bought the piston kit with the piston, 2 rings, wrist pin and clips together. The wrist pin bearing was separate. Got them off Ebay from Jawzy's Powersports. The piston kit was $98 with free shipping and the small end bearing was $13 shipped.

The Athena gasket kit was from Adrenaline Ent and was $55 for the whole engine kit with free shipping. I shopped around trying to support good dealers, but they couldn't get close to these prices and I waited too long to have them order the parts in time to get it done by weekend after next.
 
Got everything today. The gasket kit is really the whole motor, with every o ring imaginable. The Wiseco kit is top flight, the piston came in a nice soft cloth bag!


BTW, got the gasket supplier wrong, speed outfitters
 
Cool thanks for the info.

I'm gaining confidence, ready to give this a try when I save up the funds. Hope to do it in the next 2 months.
 
Here's what I got apart before work today. Piston from exhaust side looks very good! Will get the intake side off after work and get to the nitty gritty tonight. 20160112_104616.jpg
 
My new compression tester must suck because I know for sure it had more than 95psi or I could have started it with flip flops. Anyway, it surely needs a piston...
20160113_173112.jpg
 
The cylinder is perfect and it's a C btw. It certainly shows the tell tale wear on the intake side I've read about. Glad I didn't ride it any more. The morning light will have me scraping old gaskets off and trying not to put it back together wrong. It's been a long time since I took the top end off anything. And that bike didn't have all these pesky water hoses and power valves.
 
2 strokes are so simple just dont put the piston in backwards and the rest is obvious.
Any upward movment in your conrod? Check it in all its rotation if you get that.
Like crank at top of circle bottom front and back pull and push on the conrod to see if there is any movment, hold the crank still an yank with the other hand.
Nice job.
 
Thanks Juicy. Luckily they put an arrow on the shiny wiseco. It's amazing to see that kind of wear and scuffing on a piston and no evidence of anything in the cylinder. That nickasil stuff ain't no joke.
 
I'd like to see what kind of wear you get out of the Weisco. I prefer a forged piston but I always set the clearance at the big end of the specs. Forged pistons will expand much more when hot so on my 125 I went with .0045" . I have heard of some 4 corner seizures on WR300s and some on 250s, I think this is due to setting them up too tight and then getting them hot.

I just did my top end with a factory piston only because I got such a good run out of the original. I might go forged next time if I can find a piston that matches my bore with plenty of clearance.
 
I was sort of concerned with it since I ordered the piston before I even took it apart. I guess since I don't have a complete set of machinist measurement tools and I need to get it together and broken in this weekend for the race the next weekend after, I will just cross my fingers and hope for the best.
 
Huskynoobee said:
I was sort of concerned with it since I ordered the piston before I even took it apart. I guess since I don't have a complete set of machinist measurement tools and I need to get it together and broken in this weekend for the race the next weekend after, I will just cross my fingers and hope for the best.
Click to expand...
It would be easy and only take a few minutes to take it to a machine shop and have them dial bore check the cylinder and mic the new piston, then subtract and you know your clearance.

A cast piston can be run much tighter, the up side of the forged piston is that it's lighter and stronger and it can be lightened ever further if you want to get tricky.
 
I'm doing the top end on my '11 300 now also, I have discoloration on my cylinder wall and blowby on the piston, exhaust side (will verify). Have not ordered parts yet as I just took the cylinder off over the weekend.
 
Well Doug I decided to invest top dollar in a HF fractional dial caliper for inner and outer measurements on my way to get some welding done on a radiator and guard that had snapped tabs. Then I got to thinking, the specs in the manual for piston cylinder fit are for cast slugs, so who knows what it should be for a forged slug?
 
It varies depending on the alloy mix of the piston. The lightest strongest compounds usually expand the most, I had a 4.380" bore set of pistons that required a minimum of .0075 and .009" max, when you started it cold you could hear every piston knocking. The Weisco in my 125 has .0045 and seems perfect which means that I'd probably put .005" in my WR250 if I used a Weisco. I don't know what clearance is called for but Weisco should provide that info.

A dial bore gauge works the best but you can also use a telescoping gauge with and outside micrometer or an inside mic and an outside mic. The dial bore makes it easy to spot out of round but that can still be done by checking in several locations with a telescoping gauge or an inside mic. A dial caliper is not a good way to check the cylinder, it might be ok on the piston.
 
It's not good for either...it only reads .01 resolution. I did the slop check and it rattled around pretty good with no rings on it. Haha. The new ring gap was very good though.
 
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