SFC1000 - 530 chain making contact with engine case

S

stivesvelo

Junior member
Location
Cambridgeshire
Hi I'm in the process of tidying up (the bike's been off the road for about 15+ years) & have the engine on the bench, pulled off the sprocket and noticed that the chain has been making contact with the engine case and wonder why.

In 2003 the engine went to Alan Bell at Miura to replace a worn output shaft + needle bearings and output bearing whilst it was apart after which I put it back in the bike with new sprockets & 530zvm x ring chain from Sprockets Unlimited, replaced wheel & S/Arm bearings, used it occasionally for a couple of years & for various reasons it has sat under a cover since so I am now resurrecting it.


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The inner face of the gearbox sprocket shows where the chain has been rubbing, apart from that no signs of wear on teeth of either sprocket, so I'm wondering if a thin spacer behind the sprocket (or a thicker one than the one already there) would help give a little clearance, or is it because I have a heavy duty chain and need to change it for a lighter one?

Any suggestions?

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Nothing comes to mind immediately, will check if there's any movement in and out on the sprocket with the locking plate in position but not much else I can check without having engine & swinging arm back in the frame to check alignment, but am sure that's all ok & even if it wasn't how would it cause the groove.
All I can think of at the moment is a clearance issue or a piece of debris been taken around in the chain & machining the groove??

Rob
 
They all do that, Sir...

Quite common, modern chains are considerably wider than what the engine was designed for. Very wobbly sprockets can also exacerbate the symptom. The chain will have modified the rear edges of the crankcase as well.

Do not add any spacers, you will only experience difficulties re-attaching the sprocket.

For peace of mind, fit a narrower chain. Or use it as is, it's already made itself some working space.

The non O-ring #520 chain on my 3C (identical crankcase casting) has lots of clearance. ;)

piet
 
I've measured the width of the old (630, was it 630 on left?) & new(er) 530 is wider.
As Piet says it's already made it's own working space, maybe I should just leave it or get a narrower chain set as new sprockets don't fit the old chain which should supposedly be the same width.

Who supplies chains in UK now as it looks like Sprockets Unlimited may have gone?

Rob

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Hi Rob.
I have own 2 SFC 1000, and I use 530, No problem 🧐👍👍 but you Can also use : 520, I use 520 on my Laverda Endurance , I have a 120 g SFC 1000 engine.
Br
Peder Heise
 

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stivesvelo said:
I've measured the width of the old (630, was it 630 on left?) & new(er) 530 is wider.
As Piet says it's already made it's own working space, maybe I should just leave it or get a narrower chain set as new sprockets don't fit the old chain which should supposedly be the same width.

Who supplies chains in UK now as it looks like Sprockets Unlimited may have gone?

Rob

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Just go to the local bike emporium, buy a chain, cut it to length and rivet it.
Paul
 
I have had more luck lately with a 5-inch angle grinder and a lump hammer as an anvil, a centre punch and a ball pein hammer. Chains apparently are much tougher than they used to be. My Renthals chain braker broke.
 
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dont use a 630 chain, they are horrible and make the gearchanges much worse, bin them, 530 non O ring does not suit high mileage people, but will gic=ve you that little bit of extra clearance, I have use 530 O ring type for decades, the wear damage does not get worse, 520 can also be used and gives massive clearance esoecially if non or ring (as used on most GP bikes) but the sprockets are not readilly avaialbale, the pictch is the same, so 530 sprockets 19 front and 40 rear can be used but first there is a need to machine off metal to make them thinner, do this on the inside (of course) and you need a clever machinist for the front one, because they are very hard

530 = 5 (1/2 inch) and 30 (3 of 1/8ths of an inch)
520 = 5 (1/2 inch) and 20 (2 of 1/8ths of an inch or more correctly a 1/4 inch)
and yes, all is still very much imperial thanks to British supremity and the frogs not cottoning on (and they still cant make cheddar!)
CLEM
 
CLEMTOG said:
dont use a 630 chain, they are horrible and make the gearchanges much worse, bin them, 530 non O ring does not suit high mileage people, but will gic=ve you that little bit of extra clearance, I have use 530 O ring type for decades, the wear damage does not get worse, 520 can also be used and gives massive clearance esoecially if non or ring (as used on most GP bikes) but the sprockets are not readilly avaialbale, the pictch is the same, so 530 sprockets 19 front and 40 rear can be used but first there is a need to machine off metal to make them thinner, do this on the inside (of course) and you need a clever machinist for the front one, because they are very hard

530 = 5 (1/2 inch) and 30 (3 of 1/8ths of an inch)
520 = 5 (1/2 inch) and 20 (2 of 1/8ths of an inch or more correctly a 1/4 inch)
and yes, all is still very much imperial thanks to British supremity and the frogs not cottoning on (and they still cant make cheddar!)
CLEM
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No Clem.

The "5" also denotes x1/8", ie 5/8". Half-inch chains are designated "4", for 4 x 1/8". Guessing you may be a secret fan of the decimal system...;)

Doubt it is due to british supremacy though, simply too much hassle to change it to metric on a global scale. Chain standards were introduced before the metric system made an impact. Same for wheel/tyre sizes, etc. Reckon "520" etc. was introduced because few could get their heads around 5/8"x 3/8". Lavs run on either 5/8"(520/530) or 3/4", 6 x 1/8" in case you flunked arithmetic, (630) pitch chain.

Reckon the frogs don't even WANT to make cheddar...

Not difficult at all to machine the fronts, just consumes a lot of time.

piet
 
sfcpiet said:
Reckon the frogs don't even WANT to make cheddar...
Click to expand...
Traditionally, one says there are 365 types of cheese in France, one for every day of the year.
There are of course a lot more.
Unfortunately, foreigners are imposing the use of pasteurized milk. A bit like Omo, to wash whiter than white.
Pasteur was French and he liked his cheese made from unheated milk.

Paul
 
One of the best chain tools I've come across is the "Whale". Sturdy and indestructable, mainly because each size caters for a dedicated chain pitch. Seperates chains in seconds, riveting doesn't take much longer.
cea.de

Whale chain tool chain riveting tool professional - for solid rivets

CEA Shop Chain tool professional - from Wahle, for all RK and DID chains with the pitch 520, 525, 530 and 532. The basic tool is only designed for full rive
cea.de cea.de

Rather expensive, but very effective. Just need a decent-sized hammer to work it.

piet
 
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