Engine wear and tolerances

All items are for the 400/450, they may also be for the other models.

To confirm differences check out your bike's sector at the bottom.

Light blue for 470/501, light yellow for 550/650.

Also see Year recognition and changes and Common faults to incorperate any chnges into the rebuild.

Husaberg 400/450 Models

Wear limits and tolerances

Wear limits & torque values

Rocker arm differences

There are different rocker arms for the big valve heads compared to the SV heads. The easiest way to check what you have is to measure the valve diameters first. Are they 37/30 or 35/30 (some 400s had 27mm exhausts)? Next the rockers then. Measure to the outside of the screw threads with a vernier.

Small valve rocker Inlet: 44.3mm; Exhaust: 40mm

Big valve rocker Inlet: 45mm; Exhaust: 43.2mm

Rocker Roller check bulletin (JoeUSA)

Oil level

Oil level (DaleEO)

Con rod side clearance

Con rod side clearance should be set at 0.4 - 0.5mm. (Ausberg)

Head gasket thickness

Thickness of standard gasket is always .056" or 1.4mm. A thicker gasket is available than standard.

Piston skirt to barrel gap:

OEM Husaberg Piston / Cylinder clearance is .002" - .0025" (Lineaweaver).

Little end sizes

All have a little end of 20mm EXCEPT the 350/40 which has an 18mm little end bush. The bushes are interchangeable. (JBS Racing) However, all 20mm bushes spin regardless (Lineaweaver) because the bush material is thinner and looses it's compressed state.

Crank end float - axial clearance

You can measure this by tightening the cases and using a 'deadlead' hammer and slapping the crank from left to right. Two or three efforts like this and the crank will be as free as it's ever likely to be. Slap the crank one way, then, using the foot of a vernier, measure the lip or drop from the bearing to the crank. Now slap the crank the other, measure, and the difference is your float! The KTM clearance for the very same bearings is 0.21mm and this should be used for the Husaberg(Lineaweaver).

Main bearing update for all Husaberg model motors (JoeUSA)

Skim the barrel/block

Raise compression or for warpage. See this UHE Forum Thread. The spigot should be flush with the block or can be proud by up to .005" (Lineaweaver). It may pay to have the spigot and crankcase machined separately.

Rocker end float

Is .15mm (.006") (Simon). Don't have this? Fit the rocker cover screws then tap the black end caps inward till you do!