feggin bikes

01 r6 with approx 55,000kms

For about the last 12months this bike refuses to idle nicely, and is boggy
down in the low revs (getting off the mark can be annoying)

I have had the valve clearances checked, and a fresh oil change seems to fix
the problem temporarily....but the problem comes back after a few weeks.

I recently pulled the petrol tank off, and the crankcase breather is pouring
out white smoke, it seems this smoke is making the engine stall at idle. I
ran the crankcase breather into a glass jar for approx 10minutes, and ended
up with 3 drops of oil only in the jar.

At this stage I ran a garden hose from the crankcase to the rear taillights,
now the cranks venting to the atmosphere and the bike suddenly will idle
fine, and is much more responsive.... its running like it was when I first
got it.

I then proceeded to take it to my local bike mechanic, who stated the smoke
looks like a head gasket job, but that the smoke isnt coolant burning
(doesnt have the smell), and because I havnt cooked the bike before, and its
not using oil or water he thinks its somthing else ( he also stated these
shouldnt blow head gaskets as they are wafer thin)

The mech also stated he hasnt seen a crank smoke and be under this much
pressure before and in his best guess, the bore/ring may be glazed.

What a nice suprise just before I leave for the Oxley highway tomorrow, so I
want to throw a few questions to the group.

1.This problems been around 12months, If I just keep the crank vented to the
atmosphere Im assuming I will probably be ok for a xmas ride involving a few
hundred kms and lotsa revs?

2.Anybody else wanna have a stab at a diagnosis?

3. Will a top end rebuild just cost my arm? or my arm and my leg

4. Whats just a de-glaze roughly worth too on its own.

5. Is it still harsh week? Be gentle Im not real mechanically savvy

Cheers
Daniel

 

Head gasket, no. White smoke from EXHAUST means water in combustion
chamber (head gasket, cracked head, etc.) White smoke from crankcase
suggests blow-by.

NOT specifically motorcycle related, but you'll get the gist->
http://www.misterfixit.com/blow-by.htm

If it's been doing it for a while, it's probably just a symptom of an
engine that's getting increasingly tired. I don't know what sort of oil
you're currently running, but it may be worth getting some advice in
this area. There may be an oil better suited to an engine in this
condition. I wouldn't let it stop my immediate plans to ride, as it's
unlikely to result in any sort of spontaneous catastrophe, but I'd be
booking it in for a top-end rebuild when you get back from your trip.

Both arms, one leg (including your hip pocket).

 

Also.. look at http://www.bobistheoilguy.com/blowby.html

There is a suggestion that certain oil additives/ingredients may help
by cleaning sooty deposits (which worsen blow-by).

 

Blow-by. Your rings/bores are fucked, and probably your valve guides. You're
gonna have to split the cases.

Theo

 

+1 and find a new mechanic that knows WTF he is talking about

as you have found hot oily air doesnt let the bike run too well , fit it
into a
catch can and ride it till it dies

 

i had a car that did that, it was blockages in the crank case rebreather.

 

In quick response

[1] case splitting is mandatory!
[2] every man and his dog will have a go!
[3] you may need to part with a testicle!

[4] Deglazing the bore is a piece of piss and costs a couple bucks. This
recipe comes out of a catepillar manual from the turn of the last century
and works a treat on anything that needs deglazing.

- get yourself a small container of Bon-Ami.
- remove the airbox/filter from your bike to expose the air intakes
- wind motor over and hold revs at around 2500rpm (more if the bike stalls
on the next step)
- gently trickle in a handful of Bon-Ami down the intake (spread it out over
all of them). White smoke and crap will spurt out of the exhaust ( do not
confuse this smoke with crankcase overpressure or terminal engine failure)
- Start at two handsfull of Bon-Ami and see how that goes. Use more if
needed.

This method works very well on most bores that require deglazing. The old
Cats (and many other large lazy engines) as well as the 2 litre Sigmas were
notorius for bore glazing.

The good news is that it won't destroy the motor and if glazing was your
only problem you should get 1000's more out of it.. The bad news is that if
it doesn't fix the proble then you will need to resign yourself to [1] and
[3] as bore glazing wasn't the problem.

Bon-Ami is only a couple of bucks.

 

Are you serious?

 

Maybe I should have googled this first... It would appear as though he
IS serious.


Google bon-ami + deglaze

 

I remember helping a mate 'run in' a new model aero engine with toothpaste.
We rubbed it on the bore, not squirted it into the carb.

Ran it next day at 120 mph, very close to the world record speed at the time
for control line flight for that engine size.

At the time he already held the Oz record for that class.

Theo

 

Brasso also works , if it's carbon you dribble water through the motor

 

It works ,we used to use it to de glaze diesels that were driving
generators .If the engine dosen't run at a minimum of 70% full load it
will glaze the bores.

 

You learn something new every day...

.... even around here.

 

My ISP is slow to update its messages so im not sure where this will appear
(Ive been following on google groups)

Thanks for all the info + links guys, I've now got a better understanding of
whats happening. Regarding the Bon-Ami / Brasso etc. I did have a friend
suggest somthing similar (ajax into the airbox) but he also reckons it would
stuff the engine over time and to only do this if I wanted to trade it in
somewhere... ?

If I try Bon-Ami - Do I have to get it back out of the cylinders somehow
once its done its work?

Cheers
Daniel m

 

It will wash out with the fuel. I'd be a little concerned about the oil
filter though.

Theo

 

You run the brasso and then do a fliuds and filters .
Normally it's a car sales thing

 

Yup! Sure am. As long as you don't shovel it in, then all is good.
Shovelling the Bon-Ami in can lead to problems but trickle feeding is good.

I've used this effectively for a couple of decades at the garage - amazes
the customers when they nly need to fork over a couple of bucks to stop the
smoke.

The method does come with a warning. It is not a cure, just a band aid
solution as the root cause of the glazing still exists be it whether you
ride like your nana and never give it the berries or whether you have a
mismatch between ring and bore material ala Sigma.

 

You don't need to get the Bon-Ami out of the cylinders, you trickle it in
while the engine is running and the normal suck, squeeze, bang and blow of
the engine will spit it out the arse end.

 

Bon-Ami is your good friend?

Theo