Glazed pistons?

bhendron · May 26, 2016

Checking on a local ad for an '06 FJR and owner claims low compression due to "glazed pistons"? I don't think I've heard of such a condition. Does anyone know what they're talking about? What would cause that? There's enough wiggle room in the asking price to replace with full donor engine/tranny and still come out pretty, as long as no other harm was done.

Viper Pilot · May 26, 2016

Maybe he works at Dunkin Donuts!

RossKean · May 26, 2016

BS. But if you can get a good donor engine for $1000 or so, it could be worth it if the price is exceptional. The problem may be that you buy the donor engine and it is even worse!

How many miles on the bike? Might be something simple or evidence of tremendous abuse.

bhendron · May 26, 2016

It's an '06 with 50k miles and they're only asking $1000.

Ignacio · May 26, 2016

bhendron said:
Does anyone know what they're talking about? What would cause that?

Yes and Google is your friend.

RossKean · May 26, 2016

Wow! Can't go wrong, no matter how badly it was abused (assuming not wrecked). Worst case scenario, chop it up and part it out.

Spud · May 26, 2016

RossKean said:
Wow! Can't go wrong, no matter how badly it was abused (assuming not wrecked). Worst case scenario, chop it up and part it out.

Oh I can think of worse. Does it have a title? Is it stolen?

RossKean · May 26, 2016

Spud said:
RossKean said:

Wow! Can't go wrong, no matter how badly it was abused (assuming not wrecked). Worst case scenario, chop it up and part it out.

Click to expand...

Oh I can think of worse. Does it have a title? Is it stolen?

There is that! Would definitely want to make sure that it is legal!

Walter · May 26, 2016

if the bike does have the indicated issue then why donor engine? pull the top end hone the cylinders and put on new rings then reassemble and all should be awesome. A cheap fix if your willing to do a little work as parts shouldnt cost much. rings, gaskets a hone if you dont have one and all the fluids. might as well do valve job and replace CCT and you should have a nice motor good for another 100k easy.

PhilJet09 · May 26, 2016

If that's the case, it's the first I ever heard of on an FJR. If the low compression is coming from the cylinders, it's most likely due to sticky rings, which is pretty easy to fix.

RossKean · May 26, 2016

Walter said:
if the bike does have the indicated issue then why donor engine? pull the top end hone the cylinders and put on new rings then reassemble and all should be awesome...

Can the ceramic-lined cylinders be honed?

If trying to repair to restore power, the first thing I would do is make sure that the timing chain hadn't slipped a tooth. Next, check compression and leakdown. If low, add a teaspoon of oil to each cylinder and do it again - rings or valve leakage. Obviously have a look for stuff like vacuum leaks or a horribly set TBS. Maybe a dose of Ringfree is all that is needed but I would have to think there is more to the story for a reasonably low mileage bike being sold for $1000.

I suggested BS on the "glazed pistons". What could kill a low mileage FJR motor other than running it without oil or running in a dusty environment with no air filter?

Walter · May 26, 2016

RossKean said:
Walter said:

if the bike does have the indicated issue then why donor engine? pull the top end hone the cylinders and put on new rings then reassemble and all should be awesome...

Click to expand...

Can the ceramic-lined cylinders be honed?

I stand corrected you sir are 100% correct I didn't realize we had Nikasil lined cylinders in our bikes.

N4HHE · May 26, 2016

There are companies who bore and replate nikasil/chrome cylinders.

bhendron · May 26, 2016

Just checked back in. I bought it! Title appears to be in order, I'll let you know when I try to transfer. This may be a wild ride and I plan to take you all along with me! I'll start a new thread for the 'rescue'.

bhendron · May 26, 2016

Ignacio said:
bhendron said:

Does anyone know what they're talking about? What would cause that?

Click to expand...

Yes and Google is your friend.

I did google. Admittedly, quickly and didn't find much. Thanks for the link. PO claimed that indeed the engine may not have been broken in properly and babied for it's whole existence. I don't know about all that, but hey, we'll see.

escapefjrtist · May 26, 2016

bhendron said:
Just checked back in. I bought it! Title appears to be in order, I'll let you know when I try to transfer. This may be a wild ride and I plan to take you all along with me! I'll start a new thread for the 'rescue'.

Sounds like a fun project...I'd have bought it myself for that song!

Good luck!

--G

FJRay · May 26, 2016

I do believe the cylinders are one piece with the upper half of the case so any cylinder work would involve complete tear down.

TownsendsFJR1300 · Jun 6, 2016

Not mentioned yet is do a leak down test on each cylinder before any tear down. That'll give you a very good idea of the health of the engine internally.

The glazing of of the cylinders are a result of improper break in, IE, way too easy, low RPM's, etc when the bike was new.

And all that is speculative until a bore scope is used or the head is removed.

RossKean · Jun 6, 2016

Leak down? Post #11. In any case, whatever diagnostic stuff you can do could trump an engine replacement. If it can be brought back to life without the engine swap, it might qualify as the best deal I have seen.

Glazed pistons?

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