Fzr1000 exup crankshaft.

Hi,

I have some pictures of my crankshaft to share with you and hopefully get an opinion on the discoloration. It has one section where the shaft is blue all the way through to the other side of the material. It turns absolutely spot on from what i can tell and im wondering if this is maybe a symptom of it being ridden with too little oil.

Thanks, Eric.

doesn't look good, usually blueing like that could be excessive heat, and generally weakens the metal, i remember when learning to sharpen chisels not get it to blue as we would have to start all over again

Maybe an over tightening in that area,have you tried Plasti/Flexi Gauge , to see how the bearings are?

That's some serious localised overheating.

Is it possible it was heated to fit parts together?

Is it possible it was heated to fit parts together?

If it was then it wasn't done professionally, that would be a bodge too far

Is that the balance weight? its hard to tell from the pic

Is that the balance weight? its hard to tell from the pic

It is this one here, i will remove it and measure it and replace all bearings and stick it back and hope for the best but i does seem to be perfectly smooth. The bike was in a neglected state i soon realised after taking it apart and it wouldn't surprise me if it had run extremely low on oil at somepoint or run on the same oil for years and it lost its viscosity and film strength over some years.

I'd have thought if it was oil starvation then the rest of the crank would look the same also I'd expect the bearings to be the first things to go given they have a fairly soft coating on so it wouldn't rotate freely had it suffered from oil starvation.

I'd guess it could have been from when they were making the crankshaft but I cant see how that would have got through QC in that state

I'd say its some type of hardening process on the cam chain drive sprocket.

Probably induction hardened.

Any component that would have put that much heat into the crank would be obviously damaged.

Any chance you can stick an indicator on it and see if it's still round and true?

I'd say this is a question for a FZR1000 specialist forum, maybe this one, it still seems somewhat active. Looking at all the other FZR1000 cranks on ebay I can't see any with heat marks like that though. What I don't understand is why is it heated right there and not where a bearing is??

To make the sprocket more resistant to wear.

Hi,

I have some pictures of my crankshaft to share with you and hopefully get an opinion on the discoloration. It has one section where the shaft is blue all the way through to the other side of the material. It turns absolutely spot on from what i can tell and im wondering if this is maybe a symptom of it being ridden with too little oil.

Thanks, Eric.

20200408_134929.jpg

20200408_134933.jpg

It's either part of manufacturing or its from use lol

Found another with same on ebay

Thanks everyone for the replies, there is no scoring on the bearings whatsoever and it turns really freely. The con rods have slight left/right freeplay but nothing otherwise. As in the if the piston was compressed or combusting, i dont fell movement in thos directions.

I will just put the discoloration down 48k hard miles.

Regard, Eric.

I very much doubt that it happened whilst the bike was being ridden. Almost certainly done at the factory before fitting in the engine. Don't worry about it..