What caused this? FJR1300 Liner damage

[TT Tim]

Hi All,

I wonder if anyone on here has any idea what caused the damage in the attached pics?

The visible damage was on Cylinders 2 & 4.

Bike was running sweetly before incident On inspection there appears to be no damage to crank, rods or pistons, so suspect not oil pump failure, bike wasn't over heated, although when it happened it had just had a run on the m'way.

I've bought a replacement engine, but this is bugging the hell out of me as to what happened.

Bike was a late 2007 FJR 1300 Gen II with 135,000 miles on the clock, and had just been serviced, air, oil, plugs and filter.






Thanks

Tim

[graham22]

Wouldn't know what caused the liners to flake/crack but surprised to see original honing marks on bores of that mileage - or had it been rebored/rehoned in recent years.

[Mr OCD]

Possible previous re-hone of the bores thinning the liners?

I'd be checking the pistons / rings and bore diameters against factory specs for comparison.

[moto_traxport]

I'd make sure everything that's staying on the bike during the engine swap is working okay.

I'd particularly take the fuel injectors in for a test on a flow rig at your local specialist. If they're partially blocked / not performing well when asked to work hard then it could be running lean at high rpm. The incoming charge is partially responsible for keeping the engine cool. If the liners are going to get too hot and fail then it's going to be at that siamesed bit.

It's also quite good fun watching your injectors firing!

Edit to add - same outcome with a blocked fuel filter, whether it's a in pump design or separate thing. Although this should be part of service schedule unlike the injectors.

Edited by moto_traxport on Wednesday 24th January 16:35

[cmaguire]

Valve check service?
Has somebody re-torqued the head bolts while they were in there?
Left-field guess

[TT Tim]

Thanks for the replies.

This was an ex-police bike.

I have done 80K miles on it.

I found no evidence that it had been apart before.

Head bolts are stretch bolts on this, so can't see why anyone would retorque them, and as I do all my own servicing, I can be confident in saying they haven't been tightened in the last 80K miles.

I have a new set of throttle bodies to go on with the new engine, they include injectors.

Tim