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Throttle cable Replacement
Posted: Fri Dec 05, 2014 5:24 pm
by grant81rs
Gidday,
1978 R100RS - Never done one on an R100 before, anything to watch for? Be aware of?
Any good links, help hints or easy walk through's that you know of in regards to resetting?
many thanks
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 5:26 pm
by dougie
They need to be able to move to avoid stress. At least a good part of them.
They need to be happy.
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 5:59 pm
by Kurt in S.A.
You should have the two cables and the small chain in the throttle housing. You'll need some appropriate grease once you get the housing open. Try and slowly open the housing and see where everything is positioned. It's important that the teeth mesh correctly. One tooth off and you'll have a lot of slack before the carb butterflies turn. One tooth off the other direction and you will run out of throttle pull at top end.
Kurt in S.A.
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 6:36 pm
by SteveD
Grant, is it a single cable from the handlebar housing or two?
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 8:44 pm
by Bamboo812
Both the gears have a marked line on them. Line those marks up with the gears centered, and the rectangular tab on the cover with be able to slide into the groove on the grip. Moly grease.
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 10:49 pm
by grant81rs
Gidday,
The oldie are off and the new ones installed along with new return springs on each carburettor and also the throttle housing received a thorough cleaning with new moly grease coated on all moving parts.
The old cables had seen better days to btw
Anyways I removed the front timing cover to have fiddle at the points and I noticed that the big thicker red wire (has a black cover)with the larger spade end that fits to the diode board on the left side if you were sitting on the bike and looking down at it, well this spade has snapped in half, the spade is attached to the diode and the wire is flopping about like a cock in the wind
Does this wire come from the stator?
I also brought my first timing light and open up the peep hole, revved it up to 3000rpm and could not see any ''F'' markings, must have a better look at this
Anyway this morning I got way ahead of myself and I started to play around with the idle speed and I installed the two spark plug extensions that I brought for when you short out one side with a screw driver to adjust the idle? you know what I mean
The left side would short out and stop straight away, but the right side would not, it would not even die down in revs, nothing!! Can anyone please put me in the picture with your knowledge about why this could be...
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 11:19 pm
by SteveD
grant81rs wrote:
Anyways I removed the front timing cover to have fiddle at the points and I noticed that the big thicker red wire (has a black cover)with the larger spade end that fits to the diode board on the left side if you were sitting on the bike and looking down at it, well this spade has snapped in half, the spade is attached to the diode and the wire is flopping about like a cock in the wind
Does this wire come from the stator?
That's the B+ wire from the battery.
Re: Throttle cable Replacement
Posted: Fri Dec 05, 2014 11:27 pm
by grant81rs
SteveD wrote:grant81rs wrote:
Anyways I removed the front timing cover to have fiddle at the points and I noticed that the big thicker red wire (has a black cover)with the larger spade end that fits to the diode board on the left side if you were sitting on the bike and looking down at it, well this spade has snapped in half, the spade is attached to the diode and the wire is flopping about like a cock in the wind
Does this wire come from the stator?
That's the B+ wire from the battery.
HHmmmm the ole B+ wire ??
Re: Throttle cable Replacement
Posted: Sat Dec 06, 2014 12:09 am
by Duane Ausherman
The shorting method is greatly flawed. There is a whole lot wrong with it. Learn to do it by ear. It is faster and far more accurate.
My site has a page on the throttle procedure, but it sounds like you have it fixed. Where the throttle cables go through the tank tunnel, you must keep them away from the coil terminals. They can rub through and short out the ignition easily. It can kill the engine, or it can cause a miss are certain rpm. That one is just great to diagnose the first time around. Proper use of that rubber block that is supposed to hold stuff in place under the tank does a fair job.
Re: Throttle cable Replacement
Posted: Sat Dec 06, 2014 1:46 am
by grant81rs
Gidday
Duane - To be honest I am liking the "by ear" and also "by feel" way as today I set up my "BAF"

from the signshop (Big Ass Fan) and I had the bike ticking over nicely playing and adjusting a few things.
I spoke to SteveD on the blower and he mentioned the air/fuel mixture screw so while chatting I undone the screw and removed it, the spring was stuck and dirty, then i removed the carbie to the side and as instructed I put some fishing line through the little hole which was tight, I am out of carbie cleaner so and little WD40 was used to flush it out
With both sides done and the both screws set the full in then 1.5 turns out, it now idles down even quicker and smoother
I found that with your hand on the valve covers individually and also feeling the puffs out the mufflers and listening you can get them sounding fairly close, but in saying that I have nothing mechanical to check it with like a carb-tuner etc. but it is now idling down good.
I have never checked points or played around with any advance/retard on a bike before

so I am now going to read up and have a good look at that soon, plus check the timing and do the valves clearances
Also being not registered I cant get it out on the road for a good warm up either, well I can if I'm quick
