Husqvarna - race mods

[subarumy98]

HI Guys

Herewith some of the race-mods I have done. Keen to hear of any others out there.

Re-inforce the chain adjusters on the swingarm:

Revised lower chain guide:

Don't forget the larger petock

Keen to hear about other race mods.

Trevor

 

[HuskyT]

Where is the Petcock from? More Detail please Trevor.

T

 

[subarumy98]

The petcock is from my local hardware store - hydraulic and gas-line section
It is 8mm straight through to avoid any fuel starvation issues.

Its a nylon ball valve, but have just noticed a straight-through petcock on the www.vmxunlimited.com site that looks good too.

 

[scoott]

I bought my first Husky from Po Circuit. It was a 1980 cr 390 that came with the 412cc (aka420 ) kit, Fox Forks, and a Yamaha twin-leading shoe front brake& wheel.
After I received the bike ( shipped to Wahington state), I read an MXA test that mentioned bending the chain adjusters. I called Pro Circuit and asked what they were doing for the adjuster problem. The guy laughed and said " You must have read the MXA articel." I said I did, and he asked, " How much do you weigh?" I told hm I was 200 lbs without gear.

He asked if I had a 12" adjustable, which I did. He then tod me to tighten the axle nut as tight as I could with the 12" adjustable and I would never have problem with the adjusters. He went on to say the MXA testers were used to Japanese bikes that you had to be careful with about stripping threads.

Raced Huskies for 10 years, still race a passel of mid 80's Huskies, never had a problem. Always crank axle nut down tight.

 

[fran...k.]

Probably the next year they added a pusher type of assembly on the opposite side of the axle on that chain side. Myself I just tig welded around the little hole for the 8 mm adjustment piece a bit, perhaps twice as thick. I forgot the specifics of why but once I filled the space in front of the axle with trimmed bent pennies. I never have got injured by the ends of those adjusters in a crash or fall or similar type of dismount but they don't look like something to land on with pleasure.

It appears you have more modern shocks with rebound adjustment.

You ask for race mods. Your bike looks show grade to me though. Gluing something to the gasoline tank where the seat rubs or having it somehow that the seat doesn't rub the tank. I suppose if you keep re painting upon seeing bare metal would do the same thing.

There is a service bulletin on here and it has been discuissed perhaps a year or so ago that the dealer was supposed to add another one or two mounts to hold the airbox. I run a bead of silicone or some type of caulk which essentially glues the airbox to some frame tubes.

I have heard rumors of creating more motor mounts.

 

[subarumy98]

@Scoot: Tight nuts: yes - makes perfect sense. The axles looks heavy duty so will lean on them some more. The only reason I re-inforced as they were already bent when I got it so figured it needed help.
Show grade - The pics are fresh after a decent wash and silicone spray I have completed 3 events and a few fun rides to date, but with the jetting now sorted I will be using this baby a lot more.

Thanks guys.

 

['87 500XC]

Swapped front end to Gold WP 40/54 upsidedown forks Re-valved to Husqvarna team specs by moose racing

Ohlins rear shock Re-valved by moose racing

Front fender brace

44mm Mikuni carb jetted for 110 octane race gas

Carbon Fiber Boyesen power reeds

Custom clutch linkage with teflon cables for easy pull

Motor build by up-tite Husky November of 1991:
Extrude honed
Port timing changed
Custom expansion chamber/exhast by up-tite
Increased compression ratio
Max oversize
250WR cases with webing machined out to fit the crank
6 speed gearbox

 

[Joe Chod]

Probably the next year they added a pusher type of assembly on the opposite side of the axle on that chain side..

The 1984 400 was the 1st with the pusher add on and standard on all til twin shocks phased away from the line. Very good idea and saw some pre WR400 retrofitted

 

[subarumy98]

@87:
That clutch mod has me puzzled.
Did you lighten the springs on the inside, then add the return spring on the outside to help the arm return and bite ?

 

['87 500XC]

@87:
That clutch mod has me puzzled.
Did you lighten the springs on the inside, then add the return spring on the outside to help the arm return and bite ?

The arm is lengthened and then placed more inline with the cable so it's more of a direct pull. Then The cam inside the case is radiused or made more a centric. A full pull of the clutch only moves the arm maybe an inch probably less but fully disengages the clutch. Then to get clutch feel back as it was too easy the spring was put in place.

Hop that makes sense.