1. Husqvarna Motorcycles Made In Sweden - About 1988 and older

1976 WR 360

Discussion in 'Vintage Restoration Projects' started by Charlie Brown, Sep 19, 2014.

  1. Charlie Brown Husqvarna

    Location:
    England, UK
    Husqvarna Motorcycle:
    1976 360 WR
    Other Motorcycles:
    1969 Kawasaki Mach 3 Yamaha XJR1300
    Hi all, I'm going to restore this 1976 WR 360. I can start it ok on a bump and when it's running it goes great at 1/4 to full throttle but runs rough up to 1/4 throttle, is this normal for what is a racing motocross bike? It has the Gurtner carburettor and wondered if I should change it for a Mikuni? Thanks, Charlie

    Attached Files:

  2. grouty Auto Lover ...

    Location:
    South West UK
    Husqvarna Motorcycle:
    78 390WR, 78 390 AMX, 500 Humph
    Other Motorcycles:
    works 73 CCM 520, another 73 CCM520
    There is nothing wrong with a Gurtner. Take it apart and give it a good clean. The only down side with these carbs is finding the spares.
    A Mikuni would be a good second choice, but I now prefer the Lectron carb. Expensive, but well worth it. My 390 will start in two kicks from stone cold (and unused for maybe a month), to a half hearted prod when hot. It never did that with a Mikuni.
    One of my friends just up the road has a very original 76 360WR (ex-Shutt's). This had the Gurtner when he bought it, we changed it to a Mikuni and it runs very well. He found out in the end that there was no issue with the Gurtner, just his starting technique !
    Look forward to seeing you at a few Classic and Twinshock meets this/next year.
  3. Charlie Brown Husqvarna

    Location:
    England, UK
    Husqvarna Motorcycle:
    1976 360 WR
    Other Motorcycles:
    1969 Kawasaki Mach 3 Yamaha XJR1300
    Thanks for your view on the Gurtner. I've heard so many views on starting technique from rocking back and forth to laying it on its side then kicking etc. I can only get this one to start on a bump. Charlie
  4. Crashaholic Husqvarna
    Pro Class

    Location:
    Antelope Valley, CA.
    Husqvarna Motorcycle:
    73 450WR 6spd motor in a 75 MK frame
    By running rough I assume you're referring to a rich condition verses a lean condition, which would be a starving-for-gas type running condition.

    Attached is a Service Bulletin from Husky in the late 70's asking 76 360WR owners to modify their Gurtner carb by closing off a circuit between the Idle jet tube and the Main jet tube. Their reason for doing this was not related to the problem you're experiencing but I can say that this modification may lean the 0 - 1/4 throttle enough to cause the bike to run smoother. With the modified circuit left open the pilot jet circuit draws addition fuel from the Main jet tube which would possibly make the bike hard to start and blubber when the throttle is cracked open. One would imagine that the factory would have adjusted the Pilot jet size to compensate for this but then who knows.

    Also, keep in mind that 1/8 to 1/4 throttle is actually related to the slide size. I know.......carbs can be difficult.

    Like grouty said, if Gurtner parts (i.e. pilot and main jets, and slides) are difficult to come by and you don't particularly care to tinker then I'd say upgrade to the Mikuni or Lectron carb and go riding.

    Attached Files:

  5. justintendo klotz super techniplate junkie

    Location:
    mercer, pa/northwest pa
    Husqvarna Motorcycle:
    84 250,86 400,87 430,88 250,95 360
    Other Motorcycles:
    99 kawasaki zrx 1100
    you could have another problem but the mikuni vm is a legend and is a good upgrade over a gurtner. parts and jet availabliity is a good reason alone.
    that being said now that i have owned and fully dialed a lectron, i would have a hard time paying money for a carb that wasnt a lectron. the custom fitting, customer service, simplicity, accuracy, performance are hard to ignore. they are that good performing and that easy to set up if you have any understanding of jetting, and perhaps even if you dont!
    if your jetting is correct and ignition is correct you should have no problems starting. 2 kicks cold, one kick hot. low compression or leaking seal will ruin that of course
    even a notorious hard starter like my 95 360 starts effortlessly, no priming, rocking, tipping, sneaking up the bike, spells, or dances are needed..long as it has reeds i would be looking for a problem if a bike took routinely longer than 3 kicks to run. especially hot. four strokes would maybe be another story
  6. suprize Husqvarna
    Pro Class

    Location:
    Bendigo, Australia
    Husqvarna Motorcycle:
    WR 400, bike in a box Moto Villa 350
    Other Motorcycles:
    ktm 300
    four bangers are all technique...easy when you know how.:thumbsup:
    DaveM likes this.
  7. dkwkid Husqvarna
    A Class

    I put a 38mm Mikuni on my 75 CR360. It came off an auto. I rebuilt it with the same size jets that were in it. It ran well but was too rich at idle even with a 40 pilot jet. I ground down the slide angle a bit to give it more air at idle and that did the trick. It idles and runs great thru out the range. I tried and tried to make the Bing work but I could not get it to stop blubbering. I used the later 420 reed block as it was shorter so I could fit the air cleaner boot on the rear. since I live on a hill I usually bump start it although I have kick started it.
  8. MattyH76 Husqvarna
    C Class

    Husqvarna Motorcycle:
    Husqvarna 390 WR, 701E

    Hi grouty

    Do you mind if I ask some questions about your lectron ?

    I have a 1980 390WR and am considering a lectron as a replacement - I’m very familiar with building and tuning VM, pwk and Amal carbs, but this would be my first lectron.

    Do they actually make the 390 easier to start cold - my biggest gripe with this bike is sometimes starts 2nd kick others 222nd kick. Mine has a fresh motor and new power dynamo ignition and I have jetted to pull very smooth (which is what I believe makes it harder to start as when I fatten up the pilot she’s easier to start but a little blubbery off the bottom). The carb is the original and well worn so I think it’s time to change it.

    What size lectron and metering rod did you choose I’m at sea level in Australia.

    Were there any other gotchas like do I need an angled fitting on my carb cable?

    My local Aussie distributors recon they have all the specs from lectron for the bike, but thought I’d check in with someone who has actually fitted one and ridden it.

    Cheers
    Matt
  9. grouty Auto Lover ...

    Location:
    South West UK
    Husqvarna Motorcycle:
    78 390WR, 78 390 AMX, 500 Humph
    Other Motorcycles:
    works 73 CCM 520, another 73 CCM520
    First thing to check with using a Powerdynamo ignition is the timing. You can retard it a bit more than the original Motoplat. The Motoplat was a fixed system with no advance. So you had to advance it (Husky setting) to make it work correctly further up the revs. The PD system has an advance curve, so I retard mine a touch from the book to make it easier to start. My 6 speed is at about 1.9mm, and the Auto is about 1.8mm. Both start easy and rev out well. Modern fuels also favour the ignition a little retarded too.

    My 38mm Lectron's were supplied by 'Motosportz' from this forum. He no longer deals in these, but it was made the correct length for the Husky. The metering rod that came with both mine was the 3-2 I think. Both carbs were spot on straight out of the box. I have not touched them since. You don't need an angled fitting on the carb. They fitted fine on my 78's. Beware of the Motion Pro cable and throttle that sometimes come with them. They are crap ! Use a genuine Gunnar Gasser and you'll be fine. I made my own throttle cables.

    Hope this answers your questions.