EXHAUST CAMSHAFT WEAR!! NORMAL OR ABNORMAL

[PJONO2003]

Bike currently at dealers stripped down. Done 1800 miles since new (See saga elsewhere) Mechanic satisfied that current problem which occurred after full engine rebuild is to do with camchain tensioner spring etc.

Whilst stripped down I noticed that exhaust camshaft appeared to be blueish here and there- though only minor wear apparent on the cam lobes etc. The blueing appears to be heat related. The cam lobe profiles look okay.

This was very different to the the the inlet camshaft, this looked like new polished hardened steel .No wear on lobes etc. No blueing or wear apparant on the lobes or any discoloration.
Bike to go back together next day or so so if it is a problem it may reveal itself.

Experienced views required? Is this normal ? The mechanic seems to think it is.

 

[Jethro]

I've got my old cams in a box. If you guys want to see it to compare, let me know and I'll post them.

 

[Triple Trouble]

The cams are heat treated first and then finish machined. The actual lobes and bearing surfaces should be shiny silver coloured and have no sign of blueing whatsoever.

 

[PJONO2003]

Jethro

Re posting of pictures of cams. Would be really helpful if you could. In particular the exhaust cam. There is such a visual difference between the istate of the inlet and exhaust cam. One is as hombre describes. The other nowhere near

cheers

 

[Jethro]

Jethro

Re posting of pictures of cams. Would be really helpful if you could. In particular the exhaust cam. There is such a visual difference between the istate of the inlet and exhaust cam. One is as hombre describes. The other nowhere near

cheers

Sorry it took so long to get back, somehow I missed your post.

This picture isn't the best, but there is absolutely no bluing or discoloration at all. They look brand new and the lobes are shiny.
The discoloration you may see in the picture is either oil or bad lighting.
Hope this helps.

 

[PJONO2003]

Thanks Jethro. As they say a picture says a thousand words. The actual tips of my cam lobes are very much more "marred" than these.

To put this in further context- How many miles have your cams done. Mine have done 1800 miles?

 

[Jethro]

Thanks Jethro. As they say a picture says a thousand words. The actual tips of my cam lobes are very much more "marred" than these.

To put this in further context- How many miles have your cams done. Mine have done 1800 miles?

Those cams have about 7500 miles on them.

 

[Indyrocket3]

I have finally gotten ahold of my friend who is an engineer for Notchi bearings. He states that a brownish coloration to the Lobe is and will be considered normal wear...... but any blueish color is NOT normal. He states that you should definetally have it replaced because it has gotten very hot due to lack of lubrication or too much pressure applied to the lobe somewhere along the line, and they should also find out why it has gotten hot. He also stated that it is common for the surface to not be marred/ scored yet.....