SlowBusa

Just for my own information, what is the process of carrying out a compression test ? The bit that's puzzling me is why you need to accurately measure TDC . I don't know but I would have thought that you simply attach a compression gauge , rotate the engine THROUGH TDC and read off the highest pressure that is indicated . Surely the highest reading will occur at TDC anyway . If you are going to determine TDC with a straw or depth gauge before attaching a compression gauge , how do you then create any pressure in the combustion chamber to measure ?

Screw in the compression tester,

make sure all other cylinders Dont have spark plugs in (so engine turns over at least 300rpm)

Also turning the engine over by hand wont generate enough pressure to read properly so has to be done with starter motor

If the TDC isnt accurate then the valve timing Will be off, and that seriously affects PSI

Why are you taking the head back off?

The head gasket is now compressed which "could" make it not seal as well the second time around

EDIT: just re-read im guessing you mean cam cover?

How are you checking TDC?

Im thinking valve timing too

 

Now I'm starting to worry. I set the crank to T1 (I think - need to see photos) at the marker, and 1 piston up, 2 down. Both arrows on the cams were facing each other....

Dont trust the TDC marker in the timing window use something like a straw down the plug hole and turn over till you know where the real TDC is

I use on of these as a depth marker.....one tooth out will make a HUGE difference in PSI

How are you checking TDC?

Im thinking valve timing too

Spoke to them found out they dont like back patches being worn so yep just lost £15

I wear Levi Jeans ....but cant remember ever being told by Wrangler that I cant wear them

Last time I checked the UK was a free country

Thanks for the reply's I've dropped my local MC a message asking and see what they say about it.

 

Where do you live?

 

Not going to say actual location but my local mc happens to be the hells angels.

You will be surprised at how decent the angels can be

The london lot used to be easy to get on with anyway

The carbon is there because the rings dont go all the way to the top

Quick clean

Cylinder crosshatch looks ok

Head nice and clean

The minor vertical marks are not too deep.....if to keep I would sort it but for resale I say bolt it all back together

Your going faster than my rebuild....I forgot to take putty measurements so thats on the cards for Wednesday as i dont want to be riding with a potential bomb between my legs

The piston tops dont look bad TBH

I wouldn't worry too much about getting them shiny......just a little scrub

Unless [mention]megawatt[/mention] chimes in then its probably manufacturing marks and nothing to worry about

So back to the cylinders having scores.....

The bores in 2 and 3 could be inspected, as I left it at TDC.

The cylinder walls were mildly scored

So I assumed [mention]leener[/mention] was talking about barrels liners

The scoring on the valve lining could be manufacturing marks?

Vertical scores in barrel 2?

Don't listen to em about 125's ... no other biker will give you the nod ,not even other 125 riders ,no one will talk to you at cafes etc you'll feel like a complete loner

I Nod & talk to 125 riders

I dont care what your bike is...a biker is a biker

The cylinder walls were mildly scored.

 

Make sure you dont mistake cross hatch for scoring

Has anyone fitted these to their bikes? If so what do you think, are they worth the money? http://www.bikenation.co.uk/denali-dm-micro-single-intensity-led-lighting-kit-with-full-wiring-harness-m8-mount-dentt-dm

My friend has these on his K1600GT .......they are Very Impressive!

Following him in Dark lanes is like sunshine is concentrated in front

I bought my Busa without riding it

Just Try and get a test ride on a busa! the guy selling it was terrified of it so wasnt happy anyone riding it without buying it

What were your compression readings and whats the PSI range for your bike?

 

From what I remember, 1=165, 2=190, 3=170 just before I took it apart.

Something like that. But, no idea what they're supposed to be, until I can find that pesky Haynes book.

I did search and I think 170 psi is what its supposed to be lowest

If one was below that your bike will run a bit "funky" when its cold.....until the heat expands the parts a bit and then seals properly

Its happened to me

And best to replace all the seals or you could be doing the same job twice

Your doing well

Its looking less scary

What were your compression readings and whats the PSI range for your bike?

Am I taking on too much here?

Too late to have doubts now mate

The fact you can remove the head without removing oil cooler and tilting engine forward saves you a lot of time

I would be far more worried about the mating surfaces than the piston crowns

Rust is not good there

Start by cleaning the tops of the barrels with a soft rag and some sort of solvent then measuring the tolerance with a straight edge and feeler gauge

Discoloration isnt a problem but rough surface is

Only Reason to do a Burnout is just before a rear tyre change

A warm tyre is easier to remove (great excuse)

Fine replacing just rear

people generally replace both so that the wear ratio is close ..... usually 2 rears to 1 front.....but some bikes vary

Well Done

I would say unlikely to be rings on that low a milage.

I would go with new spark plugs and Spraying electrics with WD40, if it runs on both cylinders it will burn off oil in cylinder...

I gotta agree with onesea

Try new plugs first

Just a note dont torque plugs down hard.....about 8-10 lbs is all they will need

high torque risks stripping the spark plug thread

What mileage has it done?

Which Cylinder is the dark plug from?

How bad is oil consumption?

Dont believe them if they claim its the rings without doing a leak down test

You run the risk of a unscrupulous mechanic taking the piss because you are a woman ...although a bad mechanic will take the piss out of anyone who

dosnt know what a spindle flang rotating potato is

The ground electrode has snapped off on the blackened plug.

Thankfully its a trick of the light and camera angle

First glance and it does look that way though