Top End due to oil usage.

[Sparky]

Look what showed up today all nice and shiny and black.  "What dear no it's not new I have had that for oohhhh hours now  "

It's hard to get good lighting for the cylinders here's the best I could do this is the worst cylinder looks are deceiving as the marks look bad but you cannot feel anything with your finger nail and a light hone would probably make them go away.

[Sin_Tiger]

  in my defence it was 04:50 I couldn't sleep. Gonnie no dae that 

[BruKen]

What you doing up at that time then?


Anyway back to OP. The latest round of pics do not seem to show the same level of damage as the original. 

Regarding honing of barrels. Just dont be tempted to do them yourself. There is actually a art to it. Everything in the latest round of pics seems marginal and I am all out of advice now.  Think maybe it's time for trades advice and opinion.

[Sin_Tiger]

What you doing up at that time then?

I was counting stroker pistons jumping out of liners to try to help me    :icon_wink:

OT
If you have the option to get the liners hard line honed then do it, even with years of experience I would not do it myself without the proper gear. These spring loaded "honing" tools sold in tool stores are only good for light glaze removal at best, that's not the issue you have.

[nickjtc]

If you have the option to get the liners hard line honed then do it.......These spring loaded "honing" tools sold in tool stores are only good for light glaze removal at best....

Never having seen this done, what is the difference in the tools used in the different honing techniques?

[95tiger]

this is what a true hone is , and what most shops use


this is the flying stones of death Sin was referring to

[BruKen]

Take a look inside your barrels and notice the counter rotating spirals that make the cross hatching. Apparently the spirals, depth of spiral and density of spiral are actually rather precisely engineered to retain oil but not induce wear or break the seal. Its not a random scuffing. You have absolutely zero chance of replicating that with the DIY glase buster jobbie which should never be used either. Glazing is largely myth unless you love running the engine on idle, cold and for very short periods and nothing else. It makes for lovely bogeyman stories though.

[motoOzarks]

spring hones are for brake cylinders, some two stroke quickie stuff cause ya can, lawn mower etc.

or something you can't bring to the machine

[Bixxer Bob]

or something you can't bring to the machine...

[Bixxer Bob]

Sorry    back on topic..... 

[threepot]

Couldn't you replace pistons and liners? Would these fit?
http://www.ebay.co.uk/itm/Triumph-900-Carburettor-Model-Engine-Pistons-Liners-Fits-Trophy-Trident-Sprint-/371503019839?hash=item567f4e373f:g:0xYAAOSwv-NWZVnd

New liner and piston kit ..£125x3

[Sin_Tiger]

Take a look inside your barrels and notice the counter rotating spirals that make the cross hatching. Apparently the spirals, depth of spiral and density of spiral are actually rather precisely engineered to retain oil but not induce wear or break the seal. Its not a random scuffing. You have absolutely zero chance of replicating that with the DIY glase buster jobbie which should never be used either.

Glazing is largely myth unless you love running the engine on idle, cold and for very short periods and nothing else. It makes for lovely bogeyman stories though.

certainly not common on mainstream petrol engines. However, wrong LO, wrong injector pattern, wrong turbo intercooler temp at low load and within 500 hrs of new liner and rings you can go from a LO cons of 25 ltrs per day to over 300 ltrs per day, first hand experience ('twas a bit bigger diesel engine though)  got photos somewhere of the bores looking like the bottom of your Mums Treacle Toffee tray.

Anyway, that's not what's going on here so back OT.
You'll be needing new rings and probably at least one new piston, get the rings first if that's the way you go and use the new rings to check for wear on your existing pistons. You might feel a full new set is worth it, end of the day you have to decide what the bike is worth to you if you're going to keep it or someone else as the bill could end up running away from you. Threepot's suggestion might work out cheaper in the long run, time to sit down with your phone, a calculator and pencil and paper.

I feel for you as this is a very uncommon situation and didn't really deserve to happen to you 

[motoOzarks]

Some people really get into their work

[Sparky]

I have used this machinist in the past he is a one man show and works out of a shop on his property the shop has all the usual looking machinist stuff and it's spotless.  He has half a dozen different bikes in the corner one of them being a mint condition Suzuki 750 water buffalo.

Some very preliminary info after talking with him and a cursory look at the parts.

He felt the oil consumption was a combination of numerous things adding up, the valve stems showing carbon build up due to leaky valve seals, the piston ring end gap was on the large side of spec, the carbon on the piston head and the burn pattern on the piston crown.  Pic shows the burn pattern the clean areas near the edge ( I marked in red ) are caused by oil passing the rings.  In the right light you could see the outline of a piston on the cylinder wall which is probably because the bike had sat for a long time without being run.  The intake valves show signs of recession into the seats.  The good news is the liners would easily clean up with a hone, none of the rings were stuck in the grooves and the pistons show no signs of overheating or detonation damage.

I asked about the spark plug electrode and he said it's not uncommon to have one fall off especially on the cheapo plugs he was surprised when I said it was NGK.

I left him with the Triumph manual and he is going to strip the head to check the valve guides, valve faces and valve seats.  The cylinders, pistons and rings will all get checked to see what needs replacing.

I will report his findings in the next few days.     

[nickjtc]

This is all very interesting stuff.

On a similar note I have just taken the head off my '77 Suzuki GS750 which displayed a significant oil leak from somewhere, but no evidence of oil being burnt in the combustion chamber. The PO reported that the bike was running just fine when he parked it in '92/'93, but the combustion chambers and the crowns of the pistons look just like that. Hmmmmm.