• Husqvarna Motorcycles Made In Sweden - About 1988 and older

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 The previous version was outdated and no longer supported.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

Measuring piston/cyl clearance....your method ???

N

NFA1934

Husqvarna
Hi All,
New fella here. I've recently acquired a rather nice old WR450 from a chum not able to finish the restoration that I was helping him with.
I'd like to know what method of measurement is most preferred amongst those that rebuild/refurb the old 2T Huskys. Personally,I've always measured the cylinder at the top and bottom (in line with the intake/exhaust ports),
then measured only the bottom of the piston to determine the existing clearance between the two components.
Now,the old factory Husky manuals disregard the above procedure in favor of measuring only the top of the cylinder bore(where the ring has not contacted),then measuring once again just below that point (where the ring has ridden)
and subtracting the latter from the former to determine clearance.
There's another method I'm aware of that involves simply using(plastic) shim stock between the piston and cylinder
with the piston setting at BDC in the bore (shim material is placed between the piston crown and cyl wall.
No doubt,there's likely a few other versions of the last method....but you get the idea.
So,guys,tell me how you measure,and if you use any of the above procedures......

Thanks,
 
The barrel you make a bottom and top jig (which fits over sleeve top) for with studs and torque to spec as when barrel to bottom end and cylinder head. Then you measure front to back, side to side, at the top, also below ring cut, at botttom and twice between bottom and top. Now you will have a picture with quite a variety of values which will show how oval and barrel shaped the sleeve wears out.
Of the above measurements you take the largest and then determine piston oversize so that you can get a clear cut all the way through the metal of the sleeve when boring.
With this method i have seen bores so worn out that i had to go one oversize extra.
You measure purchased piston front to back about 5mm from bottom of skirt.
Then you properly bore and hone to tolerance with barrel and sleeve torqued in jig.
After this jig is released and you can measure again and see how much the sleeve actually distorts when released from torque spec. Dont worry about these measurements, its for interest sake and the sleeve will be fine and close to perfect as possible, with real ringseal and constant gap all the way up and down, when torqued up in engine.

The plastic guage is a waste of time and will never give a clear picture of actual barrel shape and tolerances.
 
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