stainless rocker feed lines

I was coming home on the Commando after fueling it up with non ethanol Chevron Supreme for winter storage, just thinking about what a great running engine it was, when it started to misfire badly. By keeping the revs up it would smoothen out a little, but clearly something was wrong.
First inspection showed the main fused supply at the battery to be melted. It fell apart when I touched it. Not sure how the bike continued to run, perhaps the 2 MC capacitor kept it going.

Further investigation showed some fresh oil on the head and cylinder, which are normally dry on this bike.
The culprit was a stainless rocker feed line that had lost it's plastic coating in an area where an ignition wire happened to be making very light contact. The uncoated stainless sawed right into the wire then shorted things out. The heat and arcing burned a small hole right though the line, hence the fresh oil on the head and cylinder.
It would be best if the wire did not touch the hose, but wires do touch things here and there, even on new factory built motorcycles, like it or not. With a standard rocker feed line this light contact would be a non event. With the stainless line that has both the ability to saw thru insulation and to carry current, big trouble!
I am very lucky this did not cause a fire. I had recently renewed the fuse holder and fuse as the old holder was corroded. I purchased a proper "British" fuse from Walridge. In the Walridge catalogue a warning is given to use the " British" 35 amp fuse which has a blow rating of 35 amps vs a North American 35 amp fuse which has a continuous rating of 35 amps. The warning is that the North American 35 amp will fry the wiring harness before blowing whereas the British 35 will not.
I have always used 20 amp North American Buss fuses and had no problem, they only blow when something goes to ground and then they blow before damaging wiring. Think I will go back to the 20 amp.
And to a standard non stainless rocker feed line.

Stainless oil lines are like abrafiles and will saw through anything...

I think that it's best located between head steady and suspension spring - the head steady moves with the engine but the harness mostly doesn't. I can"t quite work out why you've got so much wiring there actually...

Yeah, plastic coated and be damned... you have to route it so it doesn't touch anything.

+1
They are fine as long as this type of rocker feed line is routed properly. I will add little rubber grommets that fit the id of the rocker feed line and cut thru radial one section from the I.D. to the O.D.. Slide the grommet over the rocker feed line and strategically place these grommets where there may be a possibility for touching. I then get a small zip tie and wrap it on the O.D. groove of the grommet. Nice and tidy. I would have suspected the fuse as well. The fuse should have blown and not melt the wires before blowing.
Regards,
Thomas
CNN

Boyer ignition was added to the bike by Poke's Cycles before I purchased it. The extra wiring in the photo is for the Boyer. Not the neatest job, but perfectly functional, has never given any trouble until the stainless got hold of it.
The big white MK3 manual shows the hose position as ahead of the head steady. Last go round with the head, I did try it with the hose behind the head Steady, but recall it was contacting something or other with some pressure,so put it back in front, where it has been since 1988, except maybe not.... quite...exactly in the same spot.

Glen

Glen
You should be able to route the rocker feed over your head steady behind the springs like the photo in 79X100. I have the very same Dave Taylor head steady and I routed the rocker feed line exactly the same. You have a lot of :shock: business :shock: in front of the spring and this nice air gap for the rocker line to not interfere with anything behind the springs. I would check your wiring carefully especially the red wires to your zener diodes. Your boyer was probably acting up because the voltage drop from the battery going to a dead short.
Cheers,
Thomas
CNN

Oh yeah, I have no idea how it continued running with such a major short.
The replacement line won't be stainless, and may be a bit different in length so I will try it behind and see how it looks in there. The existing stainless one was too long to fit without rubbing hard on various items.
From memory, the insides of the big Interstate tank may have touched on the line when that rearward position was tried.

If there are problems with the harness and a rewire is needed, an 8 or 10 spot fusebox is going in. The commonly used single 35 amp fuse to protect all circuits method is pretty crude.

Glen

Although I would agree it would have been better if the braided line had been routed behind the suspension spring, the cross-over piece is often too long as supplied, and I ended up cutting mine down by about 4 inches, in my opinion this problem was ultimately caused by the mess of untidy and badly positioned wiring, and not the braided line.

Looking at the mess around the Boyer wiring and also all of the unecessary connector blocks in the factory wiring does make me think hard about redoing the electrical.

Glen

L.A.B. said:

Although I would agree it would have been better if the braided line had been routed behind the suspension spring, the cross-over piece is often too long as supplied, and I ended up cutting mine down by about 4 inches, in my opinion this problem was ultimately caused by the mess of untidy and badly positioned wiring, and not the braided line.

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+1

Had the same issue but with my left hand sparkplug wire. All I did was use some electrical spiral wrap and a zip tie or two. I check it once in awhile and never had a problem again. My plug lead was a bit long which is my fault otherwise I probably would have been OK.

65tiger said:

Had the same issue but with my left hand sparkplug wire. All I did was use some electrical spiral wrap and a zip tie or two. I check it once in awhile and never had a problem again. My plug lead was a bit long which is my fault otherwise I probably would have been OK.

Click to expand...

+1

Used vacuum hose to do the same thing with.

Another more involved option is drilling the inlet rocker shafts so the loop of hose can be eliminated

Hmmm..snagged us. How ?

Is with the Venhil brake lines, the stock that they sell is coated stainless braided line.

Another way to route the lines away from electrics



The line was sawing it's way through the tank as it was non low enough to mis it but that just took a bit of adjustment to lower it away from the tank



Jed

It appears that the braided Stainless lines end up touching and destroying things quite often, even though in every case it can be said that something wasn't done correctly. BTW Pete, mine were plastic coated, but the coating came off in places after awhile.
I contrast the braided stainless oil line which must never touch anything, other that at it's connection points, to the reinforced rubber oil line on another bike. The rubber line was used as an anchor to tie down the throttle cable and high tension leads that run alonside of it about ten years ago, when I assembled and restored the bike. 55,000 miles down the road all is fine.
Other than for cosmetics, I don't see a good reason to use the stainless line.

Glen

Commando rocker feeds reach high temperatures and stories of ill-chosen replacements are not uncommon. The banjos sit very close to the head and thicker, reinforced hose would not be an easy installation. Bearing in mind that a failed rocker feed results in an immediate loss of big end pressure and, within a short distance if undiscovered, a complete loss of oil, my feeling has always been that regular checks on the routing of a stainless line, at least in the beginning are preferable to the alternative. Failure of the oil feed is a potential catastrophe...

I managed to put a hole in the stainless one!
Were the original factory supplied lines problematic? I have ordered an original style, made in GB line from Walridge. They also offer Emgo or similar at a lower cost, however like most replacement parts, this isn't an item to scrimp on.

Glen

As well as shortening the cross-over, I fit the feed side cross-over banjo on the inside, against the head, with the bends of the fittings angled inwards on both sides and this helps to prevent the hose rubbing against the underside of the tank.