All that glitters is not gold...

Dukedesmo · 12-02-2017, 02:23 PM

Servicing the Monster today, first job drain the oil.

Found this on the sump magnet;

Pickup filter;

The oil is also a little 'glittery' so I dissected the oil filter, cut the pleated paper element out, straightened it and did a quick run over with a magnet;

Bike's been running fine and no unusual noises etc. so not what I was expecting and obviously needs further investigation, hoping not too expensive...

12-02-2017, 03:01 PM

Crikey - hope its not too serious.

Davy · 12-02-2017, 03:04 PM

I hope it's not the bloody oil gallery plug you told me to check out on mine?

Dukedesmo · 12-02-2017, 04:49 PM

Quote:

Originally Posted by Davy

I hope it's not the bloody oil gallery plug you told me to check out on mine?

I certainly hope not...

Dukedesmo · 12-02-2017, 05:30 PM

Quote:

Originally Posted by Davy

I hope it's not the bloody oil gallery plug you told me to check out on mine?

To add, AFAIK the oil gallery plug is aluminium so if it backs out you should find aluminium shavings until it finally wears through and you get total loss of oil pressure.

As such I don't think it is related to that, besides it wasn't backing out (the pic I linked to was mine) at the time of rebuild plus it was 'staked' in place when rebuilt.

Was yours OK BTW?

smiffyraf1 · 12-02-2017, 03:25 PM

whats it like starting? not the sprag clutch on the starter about to go?

Dukedesmo · 12-02-2017, 05:00 PM

Quote:

Originally Posted by smiffyraf1

whats it like starting? not the sprag clutch on the starter about to go?

It's been fine on starting, running, everything really although that doesn't mean it's not sprag related .

First step will be taking the side cases off. I can't imagine it's in the heads as rocker flaking is chrome and not magnetic but I'll be checking the valve clearances anyway so should be able to find or eliminate that, I'd really like to avoid splitting the cases.

It's something recent because there were no bits in the oil last service (a year ago), the bike's only done 1500 miles since and only 9500 since the engine was built.

Investigation will begin tomorrow.

Davy · 12-02-2017, 05:47 PM

Yea I had a really good look with a bright torch. Hard to see at first but one you get your head around it I could clearly see it's actually well in.. so have you already had your engine apart?

Mr Gazza · 12-02-2017, 06:01 PM

Fingers crossed for a loose flywheel nut and a (not too) mangled woodruff key.

Dukedesmo · 12-02-2017, 06:10 PM

Quote:

Originally Posted by Mr Gazza

Fingers crossed for a loose flywheel nut and a (not too) mangled woodruff key.

Flywheel looks fine through the 'window', it is one of those ultralight alloy ones so I think if it was loose it would be visibly wobbling, also would think it would run badly if so as the ignition pickup is on it?

Best case scenario at this point is probably the sprag or something related to it? and, given it's fairly easy to check it'll be the first thing on the list.

Shame really as I've been bike servicing all week and, other than a battle with the Guzzi tyres (which I won, eventually) things had gone well on the other two.

Save the best for last, they say...

Dukedesmo · 12-02-2017, 06:03 PM

Quote:

Originally Posted by Davy

Yea I had a really good look with a bright torch. Hard to see at first but one you get your head around it I could clearly see it's actually well in.. so have you already had your engine apart?

Glad yours is OK, actually I think the problem is quite rare but very serious so worth checking when you're in a position to do so.

I built my Monster from parts about 5 years ago, the engine was an old but low mileage unit from a breakers but as I was unsure of the mileage/condition/service history etc. and given that I was attempting to try to extract significantly more power from it, I rebuilt with all new bearings, shells etc. (did keep the old sprag though) to be fair it probably didn't need it all but at the point where I had it all in pieces and saw it was actually OK it seemed false economy not to replace them.

Actually to be honest, I bottled out of rebuilding the bottom end as I didn't want to risk getting the crank & gearbox preload wrong (and then having a problem down the line!!) plus I wanted the crank balancing so I took it to a pro to do the bottom end and then I built up the rest of it.

smiffyraf1 · 13-02-2017, 12:28 PM

Mine looked like this when My sprag had started to go last year. Although mine was a bitch to start which pointed to it. Could barely see the dmage though more feel it once i got it apart.

Dukedesmo · 13-02-2017, 02:52 PM

I've now got both side cases off, flywheel/sprag, oil pump out and dismantled along with rocker covers off and I can't find anything wrong.

Sprag is fine, no damage and works perfectly. Flywheel was nice & tight, there is no play on the main bearings, oil gallery plug is aluminium and was fine plus was staked on assembly so, although I can't see it it must be OK but even if it wasn't there would aluminium chippings rather than (or as well as) steel in the oil.

I can get a borescope camera inside the crankcases to see the gears and they look fine, similarly inside the bores (don't see how they could generate steel 'filings' anyway) all is good.

With the sides off and flywheel etc. out I can see the bearings which look fine and there is no discernible play or endfloat and it all turns nicely.

The gearbox shafts, both clutch and output have a little endfloat (0.14mm clutch, 0.12mm output) but I think this is normal and well within tolerance.

So now I'm left wondering....

Davy · 13-02-2017, 05:18 PM

Jezz it didn't take you long to get her stripped to the bear knuckles.
It's a bit selfish of me but I really hope you post detailed info Preferably with pictures when you rebuild I certainly could do with the help.

Dukedesmo · 13-02-2017, 06:09 PM

Taking it apart is the easy bit.

I'm not planning on going any further to remove the cylinders or split the engine as I can't see what in there could be the fault. So probably not much help to you with my reassembly?

If you want any info or pics just ask, I might have some pics from the original build but it really is a case of reverse procedure of removing.

I'll be rebuilding mine and keeping an eye on it with regular oil changes etc.

If I get chance I'll do it tomorrow but what started as a simple service & valve/belt check has become a semi overhaul, but at least I know the sprag and oil pump are OK...

12-02-2017, 02:23 PM	#1
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,844	All that glitters is not gold... Servicing the Monster today, first job drain the oil. Found this on the sump magnet; Pickup filter; The oil is also a little 'glittery' so I dissected the oil filter, cut the pleated paper element out, straightened it and did a quick run over with a magnet; Bike's been running fine and no unusual noises etc. so not what I was expecting and obviously needs further investigation, hoping not too expensive... __________________ M900, 916, LeMans II.

12-02-2017, 03:04 PM	#3
Davy Registered User Join Date: Aug 2007 Location: Derry Bike: M900 Posts: 358	I hope it's not the bloody oil gallery plug you told me to check out on mine? __________________ 1994 M900 Black

12-02-2017, 05:47 PM	#8
Davy Registered User Join Date: Aug 2007 Location: Derry Bike: M900 Posts: 358	Yea I had a really good look with a bright torch. Hard to see at first but one you get your head around it I could clearly see it's actually well in.. so have you already had your engine apart? __________________ 1994 M900 Black

12-02-2017, 06:01 PM	#9
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,815	Fingers crossed for a loose flywheel nut and a (not too) mangled woodruff key. __________________

13-02-2017, 02:52 PM	#13
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,844	I've now got both side cases off, flywheel/sprag, oil pump out and dismantled along with rocker covers off and I can't find anything wrong. Sprag is fine, no damage and works perfectly. Flywheel was nice & tight, there is no play on the main bearings, oil gallery plug is aluminium and was fine plus was staked on assembly so, although I can't see it it must be OK but even if it wasn't there would aluminium chippings rather than (or as well as) steel in the oil. I can get a borescope camera inside the crankcases to see the gears and they look fine, similarly inside the bores (don't see how they could generate steel 'filings' anyway) all is good. With the sides off and flywheel etc. out I can see the bearings which look fine and there is no discernible play or endfloat and it all turns nicely. The gearbox shafts, both clutch and output have a little endfloat (0.14mm clutch, 0.12mm output) but I think this is normal and well within tolerance. So now I'm left wondering.... __________________ M900, 916, LeMans II. Last edited by Dukedesmo; 13-02-2017 at 02:57 PM..

12-02-2017, 03:01 PM	#2
iMOC Guest Posts: n/a	Crikey - hope its not too serious.

12-02-2017, 03:25 PM	#6
smiffyraf1 Silver Member Join Date: Sep 2010 Location: Lincoln Bike: M1000ie Posts: 594	whats it like starting? not the sprag clutch on the starter about to go?

13-02-2017, 12:28 PM	#12
smiffyraf1 Silver Member Join Date: Sep 2010 Location: Lincoln Bike: M1000ie Posts: 594	Mine looked like this when My sprag had started to go last year. Although mine was a bitch to start which pointed to it. Could barely see the dmage though more feel it once i got it apart.

13-02-2017, 05:18 PM	#14
Davy Registered User Join Date: Aug 2007 Location: Derry Bike: M900 Posts: 358	Jezz it didn't take you long to get her stripped to the bear knuckles. It's a bit selfish of me but I really hope you post detailed info Preferably with pictures when you rebuild I certainly could do with the help. __________________ 1994 M900 Black

13-02-2017, 06:09 PM	#15
Dukedesmo Registered User Join Date: Sep 2010 Location: Leics Bike: M900 Posts: 2,844	Taking it apart is the easy bit. I'm not planning on going any further to remove the cylinders or split the engine as I can't see what in there could be the fault. So probably not much help to you with my reassembly? If you want any info or pics just ask, I might have some pics from the original build but it really is a case of reverse procedure of removing. I'll be rebuilding mine and keeping an eye on it with regular oil changes etc. If I get chance I'll do it tomorrow but what started as a simple service & valve/belt check has become a semi overhaul, but at least I know the sprag and oil pump are OK... __________________ M900, 916, LeMans II.