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 The previous version was outdated and no longer supported.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

390 surging

MotoXotica

MotoXotica

Husqvarna
AA Class
i have a 79/80 390 or.engine is a 1980.when riding it hard ,after a while it seems to be surging.idles very high and kind of pings.did not seem to notice this when just cruising the bike.i dont have too much experience riding air cooled bikes and am not sure exactly what normal is???i am using 91 octane fuel mixed 32 to 1 with blendzall and am using some blendzall octane booser.is some race fuel needed?do you think i am lean?dan
 
MotoXotica;78616 said:
i have a 79/80 390 or.engine is a 1980.when riding it hard ,after a while it seems to be surging.idles very high and kind of pings.did not seem to notice this when just cruising the bike.i dont have too much experience riding air cooled bikes and am not sure exactly what normal is???i am using 91 octane fuel mixed 32 to 1 with blendzall and am using some blendzall octane booser.is some race fuel needed?do you think i am lean?dan
Click to expand...

Sounds like your lean on the pilot.
 
Assuming the engine's been leak/pressure tested (I learned the hard way and chased jetting issues forever). Also check the 2 bolts for the head as they generally strip out & cause seating problems (and leaks).

It also assumes the interior of the carb is clean and not worn, the brass is good and the float level is in spec (see Mikuni manual elsewhere on this site)
 
been loking into jetting this old bike and was curious what jetting should be for about 2000 foot above sea level and 55- 60 degrees.noticed the needle was set at full lean.how normal is that?dan
 
Surging and high idle is usually a lean condition.

Like lefty said do a leak down test to make sure that you are not sucking air somewhere, then address the jetting
What jets sizes are you running?
What needle and neddle jet are you running?
I am assuming that you are running a Mikuni VM 38 mm round slide correct?

Air leaks suck
 
Dan, couple things to check, first, the 76 to 83 are known for sucking air in the intake spigut.
check for loose bolts, and small cracks, {very common} they also warp easy, replace the intake sigut, and she should be ready to go.
if you need an intake, shoot an email or call me..
also check for craked reeds and a reed cage housing.
 
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