Should I change my Alloy Large Idler Gear?

Tom Gaynor

Well Known and Active Forum User
VOC Member
Chains

You've met the dilemma I faced. The Vincent doesn't need a 3/8" motorcycle (530) chain. My 900 Monster (71 bhp) has a 1/4" (520) o-seal chain which is perfectly adequate (steel front sprocket, ally rear). The reason is that Renold isn't motorcycle chain, it's industrial chain, designed for constant loads in clean conditions, with constant lubrication. Oh, just like a motorcycle, I hear you say........
The only specifically motorcycle chain Renold made was Renold GP, as issued at the TT, distinguished visually by having no chamfers on the sideplates, and rumoured to be subject to different heat-treatment, and pre-stretch. If you want a motorcycle chain, buy the chains (that I assume) Hondayamasaki commissioned from DID, Tsubaki, et al once road-bike horsepower got serious. Just look at the sideplates........

Now listen very carefully, I will say this only once.......

Renolds 3/8" chain is 19.5 mm outside width. There isn't a lot of room either side at the gearbox end.
According to my numbers, Tsubaki 520 is 17.4, Tsubaki 530 is 22.8 (I have some doubts about this, it ought to be 20.4, 17.4 + 3), o-seal 520 is 21.25, o-seal 530 is 22.55 (it ought to be 24.25).
The ones I've measured are Renold, Tsubaki 520 (I use it on the Manx) and Tsubaki 520 o-seal (Ducati). The other dimensions are from a Tsubaki website.
On the face of it, the best option is a Tsubaki 520 o-seal (unless you have a 70 bhp plus Vin) - but enter "faffing about" which means thinning sprockets. Don't ask how I know this, but thinning ally rear sprockets is a bug pause ger (device to bodyswerve Vin-nanny) of a job, and means clamping them to a faceplate: chucking them doesn't work because they spring.

If you chose to stick a verynear calliper across your 530 o-seal chain I'd be very interested in the maximum width.
 
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Shadowman

Well Known and Active Forum User
VOC Member
Which is the best chain?

To answer Toms point
The chain I fitted is a DID 530NZ Heavy duty, Professional, Motorcycle chain. (I'm quoting what it says on the box)
It is not an O ring chain but it does have thicker side plates than the DID 530 I removed. The pins on the new chain are 22.5mm long.
I take Toms point that my Vincent probably does not need such a chunky chain but perhaps in my ignorance of such things I assumed that by getting a 'heavy duty' chain it will last longer and will be less likely to fail in my forthcoming 5000 mile journey.
Perhaps now that I've read Toms measurments of O ring chains I'll consider one next time. (If this one ever wears out!)
 

Tom Gaynor

Well Known and Active Forum User
VOC Member
Chains, my baby's got me tied up in chains; and they ain't the ki-eye-eye-ind that...

Sorry, flashback time there......what second string Mersey band recorded that?

My conclusion is that the Scott-oiler is one of those fit-and-forget devices that means that whatever chain is fitted, max life ensues. It does however look as though suitable 3/8" (530) chains that WON'T machine themselves clearance in my Vincent, can be bought , and while I don't give a toss about o-seals, really don't want the hassle of machining sprockets.
My intention was to do some good by "revealing" that narrower chains were adequate. My reward is the revelation that "faff-free" 3/8 chains are being sold........another win for Family Vincent......
 

BlackLightning998

Well Known and Active Forum User
VOC Member
I've got a Scott-Oiler on my CBR1000FL

I've got a Scott Oiler on my 1990 Honda CBR1000 FL. Not sure of the BHP - I'd guess "more than adequate" as I've seen the numbers one, four and five on the speedo - perhaps even at the same time although I couldn't possibly confirm that or Vin-nanny might have me reported for non-sensible behaviour! (Of course it was on the Continent, consenting adults and protective clothing etc etc).

I had the scottoiler fitted when I bought the bike new in 1990, I've toured, 2-up including a 3500 mile trip to Southern Spain and back.

With 18000 miles on the clock it is still on the original chain and sprockets, and I've never once had to adjust the chain between services or tyre changes!!

If you can find a good location for the scottoiler and a sensible method of actuating it (the 4mm hole idea) then I think it is a fit and forget answer to your 5000 mile trip.

Stuart
 
R

robinlw

Guest
Guarding the lower run too.

On otherwise the standard setup I have fabricated a lower chainguard (from scrap sheeting) about 4" deep for my twin, attached to the convenient torque arm. Most pre-war rigid machines had them & as riding has been my mode of transport for fifty years, thus a high mileage, I first cottoned on to saving money by making a guard against water & dirt being thrown off the tyre on to the inside of the chain to be squeezed against the sprocket teeth on my new Douglas Dragonfly, though I seem to remember that first effort didn't allow suitable clearances..... I noticed Ron Kemp had also done this some years ago on his Shadow & perhaps Russell can confirm this.
Then there's always Tony Maughan full chaincase design not to mention the short-lived Peter Furlong one (if you don't need to turn your wheel round to use the other sprocket when entering mountainous country or attaching a chair!)
 

stumpy lord

Well Known and Active Forum User
Non-VOC Member
HI ALL,
If any body would like one of the Peter Furlong fully enclosed chain guards we have one in the work shop unused never fitted.
Scot oilers are great, but Lubtronic are beter, no holes to drill in your manifolds just a power lead to run thruogh,and if you want a flow adjuster to go on the handle bars, so that if it starts to rain you can increase the oil flow to the chain,
cheers stumpy.
 
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