1975 860GT : Two questions

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rjk40
750 GT
Posts: 192
Joined: Thu Dec 05, 2013 10:54 am
Location: Malabar, Florida

1975 860GT : Two questions

Post by rjk40 »

Hi all,

I'm installing new chain and sprockets, and, since I am using new parts from Steve, and have no
experience in the "feel" of the new parts' installation, I respectfully need help on these two things:

1. New 530 o ring chain with clip type master link. The closing side of the master link will not slide, by hand, onto the
link pins far enough to expose the recesses for the clip. Is this normal, and I just need to squeeze the
side piece on with pliers until the recess is exposed? The old link's piece slid on nicely and exposed the recesses
without the need for pressure from pliers.
I have two new clip type master links from Steve, and they both act the same way.

Comments?

2. The new drive sprocket star washer's inner tab is long enough to keep the washer from threading onto the
threaded part of the shaft. The old washer's tab is considerably "shorter", and bent enough to allow the washer to thread
onto the shaft's threads, but has a really sloppy fit into the slot on the shaft once seated.
Do I grind and bend the tab a bit until the washer threads onto the shaft?
Or am I missing something?

Comments?

Thanks in advance for any helpful info.

Regards,
Richard in Florida
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Craig in France
Paso 750
Posts: 925
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: 1975 860GT : Two questions

Post by Craig in France »

Hi Richard,

1. New plates are often/usually a tight-ish fit. Just tap the side plate down over the pins using a little drift - a small socket, for example - and a light hammer. If it seems tighter than that, come back to us.
P.s Simply rotate the wheel until you have the split link supported in a convenient position on the rear sprocket.

And it never hurts to lock-wire the side plate + the fishtail on.

2. Sounds like the lock washer's tab is too long. So just cut it back.

P.s. As I'm sure you appreciate, they're not the greatest way of locking anything on to anything. So don't feel shy of using a dab of Loctite :-). And the nut needs to be tight - 60ft/lb.

HTH

Craig
rjk40
750 GT
Posts: 192
Joined: Thu Dec 05, 2013 10:54 am
Location: Malabar, Florida

Re: 1975 860GT : Two questions

Post by rjk40 »

Thanks kindly, Craig,

The info really helps, and gives me needed assurance that my curiosity in these areas
is not completely unfounded.

I shall follow recommendations in both areas.

My last experience before this with master links was on my 1969 Norton Commando
in 1974 (loved that bike, even with the Lucas electrics). Good old Isolastic engine mounts.
Not so much fun with the Whitworth threads/wrenches here in the colonies.
Things have changed a bit since then. I agree on the safety-wiring as well,
and will continue with that; inexpensive insurance.

Yeah, the sprocket washer tab , and getting it past the shaft's threads,
is a bit "hokey" (as we say here in the colonies...). I'll just be very careful to not
take off too much meat of the tab. Also, slightly bending the tab toward the engine
might be a good idea, if I can do that without distorting the whole durned washer.
Good thing I bought an extra one.

Regards,
Richard
rjk40
750 GT
Posts: 192
Joined: Thu Dec 05, 2013 10:54 am
Location: Malabar, Florida

Re: 1975 860GT : Two questions

Post by rjk40 »

Hi Craig,

As for the install of the clip type master link, the solution was staring me in the face. Steve reminded me that the
Motul chain breaker and riveting tool, MP-08-8058, (of which I bought one...) can be used to press the link onto the pins.
It has two press plates, one for each side, giving support to the backside whilst pressing the link on.
Another episode of RTFM (read the @[email protected]# manual that came with the tool).

Only question now is:

Since the clip type link is tightly married to the pins, how does one remove it? The chain breaker has only one pin
for breaking, and one must slide the link off both pins simultaneously. I guess I'll cross that bridge later. Have you ever removed the
tightly-fit clip links? It looks to me that the removal process might be destructive and render the link no longer usable.

On the drive sprocket, the new lockwashers are thicker than the factory one, and I was unable to bend the inner tab without
distorting the washer. It would be helpful if the tab were bent in at the factory. By the time I got enough of the tab ground off
to fit over the drive shaft threads, there was not enough "meat" of the tab left to keep me in comfort, so I re-used the
old one, which was in pretty good shape. BTW, unscrewing the sprocket lock nut, with the sprocket socket tool, was surprising:
it took little torque to loosen it, which means that I was likely running on borrowed time before it let loose. The sprocket socket really
helps to torque the nut down. I am also guessing that some of that large torque tends to shape the washer against the rounded face
of the lock nut.

Regards,
Richard
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Craig in France
Paso 750
Posts: 925
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: 1975 860GT : Two questions

Post by Craig in France »

rjk40 wrote: Tue Mar 09, 2021 8:57 am <snip> It looks to me that the removal process might be destructive and render the link no longer usable.
Yeah, might free up a bit in use, or could turn out that way. But in any event, there really isn't any reason to re-use a split link. Especially as you should get a new one with every new chain ...
rjk40 wrote: Tue Mar 09, 2021 8:57 am<snip>The sprocket socket really helps to torque the nut down.
It do! 'Tis the only way ... ;)
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