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 The previous version was outdated and no longer supported.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

Vibration

dukkman

dukkman

Husqvarna
AA Class
In a video advert for the 86 huskys a famous rider is seen saying that they had made these bikes vibration free.
Was he telling fibs [ bullsh@t ] or is my bike a one off ?
Mine vibrates so bad riding down the road [ fine in the tight stuff ] it takes quite a while for the feeling in my hands to return.
Has anyone ever cured the vibration in one of these ?
If so how did you do it ?
 
I rode my 88 250 wr yeaterday and had to go about 10 miles on the black top. I was still vibrating 10 minutes after I got off the bike. 87/88s are a little better that the 85/86 because of the longer stroke.
I wanting to put an updated front end on with the rubber mounted bar clamps and I'm hoping that helps.
 
I,ve got a rubber mounted handlebar setup but that's going on my 400.
Jim I was hoping that someone had found a fix for this in the years since they were made. [ mates one is the same ]
We have about 10 k of deco road back to the car and it's painfull.
I'me sure we left a trail of hard to get parts behind us ,the vibration scattering them like confetti at a wedding.
 
Prhaps one of the moderators will choose to relocate this thread out of restoration projcts.

In no particular order.

Just from an article I read years ago not counting vibration from the power pulses or valves there are three types of vibration. Primary, a piston and rod goes up and down or back and forth which if the flywheel is not counterweighted you get 100 % imbalance in the plane of the cylinder. If you totally balsnce out the forces in that plane with counterweight then you get 100% impalance at 90 degrees to that. There is no way to balance one of these single cylinder engines just split it up into some percentage in each direction which is probably tuned to the frame construction more than anything else. (What was in the advertising mentioned in the first post may correlate to changing this factor perhaps a year after adopting the new frame which I can see evidence of in my bone pile) For multi clyinder opposed, 90 degree vee, and I believe in line 6 (v 12 = two inline 6) have advantages. Seconday imbalance is a rocking couple as more than one cylinder are offset. Single cylinder and blade and fork rod v twin don't have this. The third kind I don't understand as well but it comes from the fact the connecting rod isn't infinately long. Depending on the engine design some of thes things can cancel out to some or total degree. The rotax 250/260 used in atk and perhaps others is the only counterbalanced two stroke motorcycle designed engine I am aware of. Lots of counterbalanced four cylce single cylinder motorcycle engines but not in this section of this website.

Having the engine firmly held in place is the place to start. Cracks can develop in the front frame tubes near the inserts the bolts go through and the engine can get loose at the rear in a number of ways from the magnesium not firmly grabbing the inserts to the holes in the frame becoming enlarged. Use your imagination what other options inbetween those I didn't specifically describe. My 430 auto was the only one in this year range that didn't have issues at that rear mount and had any significant amount of use on it, strange one can't over rev it without going like 85 mph. I have discussed this before about more motor mounts. Even the guys over in the two stroke section on here with designed head mount this section doesn't have must keep up on mount bolt torque the way I read it. At least the 250/300 model.

Do what you want but just kind of go slow in high gear, It is kind of tough to run a steady speed so easy on the throttle then idle and coast. It isn't like you would have to drop a cross member and pull a transmission to change a throw out bearing. These things generallly have extremely wide ratio transmissions by comparison with what else is out there in the motorcycle segment.
 
Didn't know where else to put this question Fran...k.
I have restored this vintage bike and the vibration remains a problem.
I have owned and raced many bikes from the 80/85 era and don't recall any of them like this one.
I was of the hope that someone had found a cure outside the obvious loose engine mounts and cracked frames.
Something like putting half an ounce of lead in the sixth balance hole from the keyway.
Cheers Mike
 
Have you restored the engine of this one? Just for the sake of discussion I will throw out some more stuff. How true is the crank? Has it been put on V blocks with dial indicators on the ends of the tapers? Is everything in the wristpin area tight, the pin fit into the piston as well as what one usually is concerned with. Could a main bearings have spit out some chumks from the race? I suspect that towards the end of production in this section of this website a nylon caged non maximum capacity bearing was used on the ignition side. When I put one of these engines together I invest a lot of effort to try and make sure the inner races on the crank and the outer races in the case are positioned in a manner that the balls will ride where they are supposed to. I kind of have made my own technique without studying the manusl but it is pretty obvious both the inner race and outer race could be positioned wrong within the amount of play in the bearings themselves. I typed a bunch pertaining to the "vibration free" phrase in the first post. Perhaps someone else can be more specific with their experiences as they wore out bunches of similar engines to what you have.

Fran
 
Total rebuild Fran..k , all new proper bearings , crank is running true [ done between centres ].
I was an engine rebuilder in my past life [ actually did it as my trade ].
The only thing I can think of is the flywheel, these things blow up the SEM ignitions so frequently and mine came with the ignition completely missing so the flywheel is of another bike.
If you put a flywheel on a mandrel and give her a spin the outside runout is surprising.
Could they have taken " hand built" to the extreme and fitted the flywheel to the engine.
I have raced a 78 CR250 and I remember it as being very nice , this bike's vibration is nasty.
There was a thread on here back before the format changed on vibration in 400's but I can't find it.
Mike
 
Dukkman... I have relocated this thread into the main forum for Vintage left Kickers... this area you posted in is for complete restorations ( as Fran mentioned ) No Biggie... Just took me a few days before I spotted this one out of place...You should see more input no from more members with higher traffic over here...

T
 
I had the same issue with my 78 390WR when I first had it. We rebuilt the engine and noticed the flywheel side woodruf key had sheared. I cleaned up the end of the shaft and lapped the flywheel back onto it. The motor ran great. But the vibration was awful. Even with the rubber mounted bars. It stayed like that for about 8 years until we rebuilt it recently. A bit more time was spent looking into the vibes. We found that the right crank stub was slightly bent on the end. This would cause the flywheel to run out and cause most of the problem ! !
(see another thread ref the compatability of these shafts).
Did it cure the vibration ? ? .............. well not exactly. I was so much better, but not completely vibe free. I don't think they ever will be either. Just something you have to put up with to a certain extent I guess. I will pay so much more attention now, when rebuilding cranks etc, to make sure they run true.
Everything Fran...k. said is true too.
 
I have 2 possible ideas.

1. If, when attempting to remove the flywheel nut with an impact gun not knowing it is reversed thread, it can crack the flywheel at the slot for the woodruff key. Next time it is installed it will wobble, and probably fail. I had one like this and successfully ground out the crack and welded it.

2. On one of my bikes (1984 xc500) one of the steel inserts on the motor at the swingarm pivot was very loose, resulting in very annoying vibration. I epoxied the insert to the motor and vibration is now not excessive and probably average for a 500cc engine.
 
dukkman said:
In a video advert for the 86 huskys a famous rider is seen saying that they had made these bikes vibration free.
Was he telling fibs [ bullsh@t ] or is my bike a one off ?
Mine vibrates so bad riding down the road [ fine in the tight stuff ] it takes quite a while for the feeling in my hands to return.
Has anyone ever cured the vibration in one of these ?
If so how did you do it ?
Click to expand...
VIBRANATORS from Ricor are a bar end that dampens almost all of the vibes out of my 82 cr500, Chuck Sun turned us on to these and they work!!!
 
My 86 400 enduro vibrated alot, they don't like to be rev d up, i always short shifted mine. I broke the upper
radiator hose once:eek:, racing it in a +40 MX race once, but i was revving the piss out of it :D. Had to tighten
my head bolts once a month, if i rode it alot. Love that bike though, one of Husky best woods bikes.

Husky John
 
Back in the 80's, I raced a 85 500xc , followed by an 87 430 mx. The 85 vibrated more than the 87, but no big deal. During the span I was racing the 430 mx, I bought a used 430 Auto to play with. The bike was virtually unridable because of a terrible vibration that seemed to max out at the auto clutches engagement rpm. Talked with the most knowledgeable Husky dealer in the Portland,Or. area about the difference in the 86 auto and 87 mx motor. Tried the mounts, etc.
Finally ended up putting an 87 rod, with a different balance factor ( much lighter) than the 86. Cured the vibration( or at least reduced to manageable level). Still decided I didn't like the auto, but at least I could hold onto it.
Whether the difference was crank alignment, bearings, motor mounts, or the weight of the rod like the dealer said, it worked!
 
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