Excessive amount of metallic flakes in oil. FS650 2004

Hello!

(There is a short/TL;DR version at the bottom of the post)

At first I'd like to apologize for yet another post about flakes in the oil. I know there are quite a few of these threads and should this one be considered unnecessary I will remove it.

To the case at hand:

I recently bought a 2004 Husaberg FS650E which has, according to the onboard "computer", logged about 120-130 hours. I do not remember exactly and I wont have access to double check until next weekend sadly.

Anyway, I rode it for a couple of hours (less than 5) after I bought it and then performed a first oil change whereupon I noticed a remarkable amount of flakes both on the oil plug, oil screen and oil filter. I have linked an album to the first oil change below. Most of the flakes not on the magnetic plug were not magnetic.

First Oil change:https://imgur.com/a/l8OZtkL


As I do not have much experience with these bikes I'm not sure what flake amount is considered "normal" and from what I've heard, these bikes to "chip" and flake quite a bit, but still it seems a bit excessive..

To my knowledge, no major service has been performed at the 100 hour mark and so I will most likely split the engine and do an overhaul in the near future.

After having emptied the oil i flushed the engine several times with new engine oil, making sure to pump the kickstarter a few times by hand to try and get all flakes out of the engine. I also replace both the oil filter and cleaned the oil screen as best I could.

I rode the bike for about 3-4 hours before I changed the oil again and this time it looked much better, atleast compared to the previos oil change. Album linked here: https://imgur.com/a/eHOL77R

Still, there are quite a few flakes on the plug, and some on the filter but is this considered "normal"?

I know that this is a race machine at heart and I knew what I was getting into when buying it, rebuilding the engine etc is not something I am shying away from but of course I would like to be able to ride the bike a bit more into the summer

So basically, my question is wheter or not this is an acceptable amount of flakes, maybe because of a missed oil change, or if it is time to crack the engine case and do a major service before it becomes more expensive than need be.

Thank you in advance!



TL;DR:
Bought FS650e 2004 @ 120hrs. No major service had been performed.

Rode for less than 5hrs, changed oil. Lots of flakes/chips. Most flakes were not magnetic Album: https://imgur.com/a/l8OZtkL

Flushed engine with new oil to get all chips out, replaced screen, & filter. Rode for 3-4 hours. Changed oil again and it looked a lot better this time.
Album: https://imgur.com/a/eHOL77R

Time for engine rebuild or was an oil change just missed which caused excessive flake buildup?

Wow! Thank you so much for your reply Taffy!

I will perform the tests you described this weekend and get back with some results.

Just to be clear, when you say "shake the flywheel in different engine positions over 2 turns", do you mean that I should try to pull and push the flywheel left-right, up-down in different parts of the 2 revolutions?

I'm guessing this is to see if there is any radial play in the main bearings which would indicate that the bearing races are worn, is this correct?

Also, is turning the flywheel to and fro meant to show if the rod big end journal is worn or is it to measure gear backlash?

Ofcourse, you don't have to answer these questions, I would just like to learn as much as I can

Thank you again!

And by the way, are there any difficulties for you to ship to Sweden what with the coronavirus and everything? Just thought I'd double check

I see, thank you again taffy!

I'll give an update when I've had time to check the bike.

Back with an update!

I removed the ignition cover and tried pulling, pushing and rocking the flywheel to the sides etc at different locations whilst I rotated the crank but I was not able to feel any play at all, at most maybe 0.1mm in a specific spot but that might just have been my imagination.

I also checked for axial play which I measured to 0.7mm, as I do not have any reference I'm not quite sure if this is too much or too little or just perfect.

I removed the clutch cover to check if any of the gears were worn so as to cause the excessive amount of flakes but I could not find any idication of abnormal wear.


I've heard that some 650 models have an aluminium camshaft sprocket so I'm thinking of taking the top off to check but as far as I'm aware, the 2004 model shouldn't have an aluminium camshaft sprocket.


Do you Taffy or anyone else have any idea on how to proceed? Would it be safe to put it back together and ride it a bit longer or should I just bite the bullet and tear the engine down while I'm at it?

Thank you again for your help Taffy!

I see, thank you! I was pretty much set on having to strip it due to it not having had any major service done to it at 120 hours so no worries

Good analogy Taffy, no wonder people are having trouble with the main bearings going when so much axial force is being put through a bearing designed for mostly radial forces!

Another update!

I've found the cause of the flakes!

The timing chain tensioner had seized completely, it was only 2 "teeth" out and I could not move it in either direction despite unhooking the ratchet mechanism.

I have not checked the timing chain tension since I bought the bike so it must've been running with a slack timing chain for quite some time...

The timing chain slack resulted in the chain grinding against the lefthand side of the valve cover and all the way down along the wall of the case. Luckily, it seems no vital parts have taken any damage so it should be enough to file down the burrs left by the timing chain, as well as replacing the chain etc.

Here's an album with some pictures for those who are interested!: https://imgur.com/a/YGVf8uR


I'll still be splitting the engine case sometime during the week so that I can change the bearings. I'll see if I can get in touch with Engine Hardware and install his "bearing upgrade". Might aswell when I've already disassembled most of the engine

Any tips or things to keep in mind when splitting the case? I've heard that some people have had trouble with the shift drum position when assembling, is there some things I should mark up before splitting the case?

I also made this copy of the OEM case splitter, will be put to the test during the week https://imgur.com/a/zX8YNmM

Cheers

I'm not sure actually, mostly for peace of mind I suppose. I've read so much about the mains going bad and eventually causing the case to crack so I guess that I felt like I might aswell "upgrade" the bearings while I've already torn the engine apart.

I'll look for some more input regarding changing the mains or not, might as engine hardware about it too.

I've tried shaking the flywheel as hard as I can but there was at most 0.01mm of play in a small part of the whole crank revolution.

I see, that very well could be the case, is there any way to stop it from happening? How has it been solved on the later models?

I will check the width and compare with the timing chain rivets

Hm, I couldn't find any indication that the decomp spring had become unwound but I will take a closer look tomorrow.

Update again:

Engine case is now split in half

Had some trouble at first as the case didn't really want so separate. But that might just have been because of the bolt next to the ignition sensor that I forgot to remove


Heated the case halves to 150 degrees C (158 actually) in an industrial oven at work, sadly only one bearing fell out without any persuasion. All other bearings had to be driven out


Began taking some measurements and inspecting the now completely disassembled engine.

The piston was sadly quite banged up. Several deep scratches, mostly on the forward skirt, that caught a nail so I'll have to order a new one.

As for the cylinder liner it had 3 scratches that caught a nail, not sure if I should let it slide or if the Nikasil will need to be replaced. Any suggestions?


I've attached some pictures of the different parts as well as 2 videos of the piston & cylinder liner scratches. Album here:



The main bearings actually looked pretty mint, might've been able to get a couple more hours out of them but oh well

The mains inner bearing races also looked very good, no obvious damaged.


Conrod "small end" bearing looked a bit banged up, some pitting in there- forgot to take a picture though. I saw that you've got replacement small end and big end bearings in stock Taffy so I'll place an order when I've made a list of everything I will need Was afraid that I might've had to replace the entire conrod but hopefully it's salvagable.

Also, the top of the conrod has been rubbing against the cylinder "roof", displacing some material. Forgot to take a picture of this also but I will take some more tomorrow.


The gearteeth on the waterpump shaft that meshes with the crankshaft balancer seem to have been rubbing up against something. Picture in the album.


Here's something I found strange! There was a seal ring beneath the waterpump bearing with the sealing side towards the engine case. I've not been able to locate this seal ring in the exploded views. Is this an original seal or something a previous owner might've mounted?

Third picture in the album shows the seal ring

Anyone ever seen it before?


That was all for now, hope someone all of this interesting or helpful

Cheers!