Tight primary chain ?

[dirtyss]

I'm just near the end of finishing a total rebuild of my 48 chief engine fitted with a 4 speed overdrive gearbox. Alignment of clutch and engine sprockets were undertaken by using around 10 - 15 thou of shimming between the trans casing mounting to rear of engine. Assembly of new primary chain, engine sprocket and clutch basket onto their respective shafts was straight forward.
With everything tightened up I'm getting 1/2" - 5/8" of chain play ... the manual says 3/4" .... will this tightness ease off after initial start up ? Should I run it at all this tight ? Engine turns nice and freely !

[tfburke3]

With out knowing anything about the 4spd od box I think you could remove some material from the contact point of the adjustment shoe lever and the case if it isnt already at its lowest.
I would also suggest to make sure the gen drive sprocket is shimmed and adjusted to center of chain.
Tom

[PaulCDF]

Dirty; I am running a Byford 4sp transmission I adjust primary according to Mike Tomas Indian Riders Instruction book: "Slack should be 3/8" "3/8 inch total deflection when cold"
Mike is good about pointing out differences between "crashbox" and "transmissions" when needed. He notes no difference for primary chain slack.

My copy of the Repair and Overhaul manual states: "When properly adjusted, the chain should have an "up and down" play of 3/8" or the distance equal to HALF the diameter of the inspection hole".

Hope this helps. Keep us posted.

[dirtyss]

With out knowing anything about the 4spd od box I think you could remove some material from the contact point of the adjustment shoe lever and the case if it isnt already at its lowest.
I would also suggest to make sure the gen drive sprocket is shimmed and adjusted to center of chain.
Tom

Ok Tom ... the chain adjuster was wound off and clear of the chain in the bottom of the primary chain case.

Thanks for the tip on the gen drive sprocket being centred.

Paul

[dirtyss]

Dirty; I am running a Byford 4sp transmission I adjust primary according to Mike Tomas Indian Riders Instruction book: "Slack should be 3/8" "3/8 inch total deflection when cold"


My copy of the Repair and Overhaul manual states: "When properly adjusted, the chain should have an "up and down" play of 3/8" or the distance equal to HALF the diameter of the inspection hole".

Paul, I have now found your reference in the Repair and Overhaul manual (which I missed several times whilst searching !) to the figures of 3/8" 'up and down' play.
My mistake was assuming the figure quoted for the Military 741B primary chain play of 3/4" being the same for the Chief ... clearly incorrect.

Thank you
Paul