750 SF2 primary chain

[Lyndoneil]

I'm removing the clutch on my SF to investigate why there is insufficient play on the clutch lever acctuating arm (It's hitting the crankcase when the clutch is pulled in) to check the push rod lengths, ball bearings, clutch plate wear etc. I was expecting to find a triplex chain on the primary drive, but found 2 single chains, which surprised me.
Would like a bit of feedback as to whether this is a good , bad or indifferent practise .

 

[sfcpiet]

If 2 single row chains were good enough for the SFC1000 ex factory, they'll be more than ample for a 750. Lots here will advocate to bin them as quickly as possible and fit a duplex, etc, etc. Pretty much overkill imho. Also lots of talk about uneven sprocket and chain wear... mainly academic, no real impact in the real world. Advantages of the duplex are its strength and quiet running.

Looks like your chains don't have much slop and the original cush drive rubbers have been replaced. Check if these are still in good condition, there should be no discernable radial play between sprocket and clutch drum.

Likely to find worn clutch plates (rare) and/or worn rods, ball and cross-bar. Replace the spring washers under the cush drive bolts with Schnorr-type washers, or just Loctite the bolts without washers. There is bugger-all clearance to the primary cover when spring washers are fitted! You may find witness marks on the stiffening webs of the cover, depending on how well the clutch drum has been spaced and bush condition.

piet

 

[Paul Marx]

Two single row chains as Piet says won't give mechanical problems, but they will be noisier than a triplex or a duplex since tension or rather slop will always be unequal.

Paul