VF400F hoping for a miracle

Hi,

Just hoping for a simple answer like 'throw some B-12 in your
tank and be happy' but afraid that the final answer will
be 'scrap the bike'.

Here is what happened:
I own a Honda VF400F, 1985. My only means of transportation.
Nice bike, but impossible to service unless you are a Japanese
midged with 3 feet long fingers and posess special Honda tools.

I've driven a couple of miles with a flickering oil pressure
light, making it to the next gas station.
Replaced a simmer-ring, added 4 litres of oil, and noticed
some miles later vibration in my foot rests at high revs that
wasn't there before.

I now have a knocking sound that seems to come from the
front left cilinder. But only when I open up the throttle
completely and the engine is hot. Not when the engine
ran for a few miles (thus is relatively cold).
Also top speed reduced from around 170 km/h to 120 km/h.
And the oil pressure light is 'on' at idle when the engine
is hot.

My brain tells me: worn out cylinder or worn out crank shaft.
But there is one thing that puzzles me: knocking goes away
when I close the throttle a bit.

I thought: Knocking may come from carbon deposit in a
cylinder, and even though I am not a Japanese midget, I
managed to take out all four spark plugs, but they looked
very good.

Any other ideas than 'scrap the bike'?

Rob.

 

Mark Olson schreef:

She blew out an oil seal (I called that a simmer-ring) and
made a 4 mile trail of oil on the road before the light started
flickering. I noticed the rear end was waving, but since it rained
the first time after many dry weeks, I thought that to be the normal
slippery of the tarmac at first rain, not a fouled rear tire.
Checking oil level is a standard procedure to me, and easy
because it does not have a dip stick but a small window in
which you can see the level.

The problem with this bike is that the crank case is the horizontal
split type and the cililnders are part of the top half crank case.
Even adjusting valve clearance takes about two pages in the
service manual. Bleed the water, remove the tank, remove the seat,
remove the radiator, remove the fan, remove the clutch, etcetera.
To inspect my former beamers cylinder, I needed to unscrew 9
nuts only. Did that many times, all in an hours work. This bikey
will cost me a week to open.
And I am scared to what I'll see then.

Your answer is close to what I don't want to hear; 'scrap the bike'
Ouch..

Rob.

 

Live with it. He's right.

 

Mark Olson schreef:

My fault.
I'm getting old. Ever since I was a kid, a simmer-ring was
named simmer-ring (in the Netherlands). The word 'simmer'
probably is German. I bet if I now ask a dealer for a simmer-ring
he won't know what I'm talking about. Simmer-rings were those with
a spring around the lip, 'olie-keer-ringen' (translated:
oil-revert-rings) looked the same but had *no* spring.
Simmer-rings were used for reciprocating things (like my clutch push
rod that does not rotate but slides), the springless type were used
for rotating axles (the ones with spring would -finally- wear a dent
in the axle because the lip would rub the axle at the same place
all of the time, of course the springless type would do that too, but
much later).

Like I said: I'm getting old..
Not so long ago I tried to buy consistent-fat. The bicicle shop
did not know what I wanted. It is now named bearing-grease.

There aren't many around, it was an expensive little bikey when it
was on the market. But they are around, so I should do what you
suggest.

To avoid going into the history books as a total moron; I was not
asking a question like: "I drove miles without oil, and now I hear
a strange noise, how come??"
The oil light flickered, was not completely on, because I would have
stopped immediately then. After the repair (oil ring) and fresh oil,
she ran fine for a guessed 200 miles. Then I started to feel a fine
vibration at my foot pegs, and a 100 miles miles later I started to
hear a knocking sound.
My guess: worn out cranck shaft main bearings.

What made me wonder is that it does not knock when cold (it
revs fine up to it's max 12500) but knocks when it is warm *and*
I jerk the trottle open from a cruising 100 km/h. As soon as I close
the throttle a bit (so that it does not have to accelerate but cruises
again) the knocking disappears.

Oh well.. The first thing I should do is to have a look at the
innards of the engine. It's gonna be a long job with a sad end.

Rob.

No list of owned bikes here.. I'm too ashamed about the Ural.