955cc into a '99 with bad 885cc?

[blume]

Greetings from Oregon!

I bought my old Girl back this week for half what I sold it for three years ago because she's a part of me, and needed some attention desperately; she had a light knock under load that led to a clatter at all rpm which resulted in a silent coast to a stop safely on the wayside on the first ride out.

There's no way I'm going to brick the prodigal Tiger, so I need options for a re-power; 955cc I think is the only way to go...
My first thought is to re-sleeve and replace the pistons, bent or broken parts (at this point undiscovered, pictures soon) and other bits that make the 885 a 955 if that is in fact doable.
Second thought is to find a 955 from a wreck and bolt it in the '99 frame.
Third option is to go back to the 885 but let's be honest with ourselves; there is no replacement for displacement, Right?

anyone here done or heard of this being done?

[metalguru]

Fitting the engine is a straight swap.
Although you will need the throttle bodies and fuel pump plate with lines. The single fuel line is much better than the twin you have now. Never tried running the 885 throttle bodies on a 955 though.
Ecu if you have the early single plug ecu this will have to be changed for the twin plug and of course the loom. If you have the twin plug ecu then just blow the 955 map into it.
The airbox has an extra hole in it clean side, this will need plugging. Exhaust down pipes are very different although I am told the 885 ones can be made to fit with a bit of fettling but the 955 system will get rid of that resonator box, the down pipe skid plate is different.
Oil cooler is in a different place but does the same job, if you use the old one it must be internally spotless as if the engine has gone bang then there could be muck in the cooler and lines.

Let us know how you get on and post some pics please.

[blume]

local dealer says the internals are a straight swap, so sleeves and pistons and, if my assumption of skipped timing chain plays out, valves, plus the associated gaskets and other moving bits....

Friend of a friend has the TuneBoy software and I'm a mechanic by training and from birth, so this should be gravy.


and Roberts your Mother's Brother.

[metalguru]

Cylinder head is different with bigger valves on 955 so if top end is mashed then way to go. Engine swap is probably cheaper easier and quicker.
Been there and done it many times.

[Chris Canning]

Definetly a full on heart and lung transfer,and to give you some idea how close the bikes are,the body work on my 955 is off an 885,what I never worked out their totally different to sit on,well the 885i you sit 'in' the 955 'on'  :?

[blume]

Cylinder head is different with bigger valves on 955 so if top end is mashed then way to go. Engine swap is probably cheaper easier and quicker.
Been there and done it many times.

is there an online parts breakdown for the triumph line that is respected?

I have the Clymer manual and there is no mention of different valves for the 955/885, but it does break down different compression ratio, HP, Torque, etc for the 955i in the Sprint; I will talk to the dealer and parts man tomorrow when they open and verify this, but I think I can swap liners, pistons and rings, and keep the same head with new valves if needed (will be tearing into it today to see) and load a Sprint map to the ECU and be set. I believe there may be changes in cam profile and duration, but without the dealers help that's conjecture at this point.

I'll be posting pictures as I get into the engine proper; stay tuned...

[Mustang]

is there an online parts breakdown for the triumph line that is respected?

I have the Clymer manual and there is no mention of different valves for the 955/885, but it does break down different compression ratio, HP, Torque, etc for the 955i in the Sprint; I will talk to the dealer and parts man tomorrow when they open and verify this, but I think I can swap liners, pistons and rings, and keep the same head with new valves if needed (will be tearing into it today to see) and load a Sprint map to the ECU and be set. I believe there may be changes in cam profile and duration, but without the dealers help that's conjecture at this point.

I'll be posting pictures as I get into the engine proper; stay tuned...

bike bandit has parts breakdown for all year tigers by model year .

http://www.bikebandit.com

click on the OEM parts link

[metalguru]

Cylinder head is different with bigger valves on 955 so if top end is mashed then way to go. Engine swap is probably cheaper easier and quicker.
Been there and done it many times.

is there an online parts breakdown for the triumph line that is respected?

I have the Clymer manual and there is no mention of different valves for the 955/885, but it does break down different compression ratio, HP, Torque, etc for the 955i in the Sprint; I will talk to the dealer and parts man tomorrow when they open and verify this, but I think I can swap liners, pistons and rings, and keep the same head with new valves if needed (will be tearing into it today to see) and load a Sprint map to the ECU and be set. I believe there may be changes in cam profile and duration, but without the dealers help that's conjecture at this point.

I'll be posting pictures as I get into the engine proper; stay tuned...

If you load the sprint map into a tiger you will find it won't run any sense and the instruments will not function as the sprint clocks are different. If you end up with a sprint top end then only the ignition and fuel maps should be copied over to the tiger map. This can be achieved via TuneECU F Trim and I trim.
If you go the rebuild route then best to strip the lump and see what the damage is and decide on a way forward pending parts required as a second hand 955 engine and ancilliaries may work out cheaper.
If 955 pistons and liners are fitted to the 855, the bore on the 855 is 76mm while the 955 is 79mm although the stroke is the same so the 955 head would have to be fitted in conjuction with the pistons.
Depending on the age of 955, the later ones used 1050 cases whereas the early ones were similar to 855.
The early cases did suffer weaknesses including cracks in the cylinder head and weeping head to crankcase sealing. The breather system created its own faults.

[blume]

Cylinder head is different with bigger valves on 955 so if top end is mashed then way to go. Engine swap is probably cheaper easier and quicker.
Been there and done it many times.

is there an online parts breakdown for the triumph line that is respected?

I have the Clymer manual and there is no mention of different valves for the 955/885, but it does break down different compression ratio, HP, Torque, etc for the 955i in the Sprint; I will talk to the dealer and parts man tomorrow when they open and verify this, but I think I can swap liners, pistons and rings, and keep the same head with new valves if needed (will be tearing into it today to see) and load a Sprint map to the ECU and be set. I believe there may be changes in cam profile and duration, but without the dealers help that's conjecture at this point.

I'll be posting pictures as I get into the engine proper; stay tuned...

If you load the sprint map into a tiger you will find it won't run any sense and the instruments will not function as the sprint clocks are different. If you end up with a sprint top end then only the ignition and fuel maps should be copied over to the tiger map. This can be achieved via TuneECU F Trim and I trim.
If you go the rebuild route then best to strip the lump and see what the damage is and decide on a way forward pending parts required as a second hand 955 engine and ancilliaries may work out cheaper.
If 955 pistons and liners are fitted to the 855, the bore on the 855 is 76mm while the 955 is 79mm although the stroke is the same so the 955 head would have to be fitted in conjuction with the pistons.
Depending on the age of 955, the later ones used 1050 cases whereas the early ones were similar to 855.
The early cases did suffer weaknesses including cracks in the cylinder head and weeping head to crankcase sealing. The breather system created its own faults.

outstanding info; thanks very much!
I was not thinking of swapping the head, but DUH; different bore would require it even if the same valves are used (doubtful)

I have the valve cover and right side cover off- the timing chain had skipped a tooth on the crank end, and I had enough time to re-index that last night but need to roll it through and verify.
I will be borrowing a bore-scope to get a look inside the cylinder and at the valves- big question for the day: Is this an interference engine? If so how many degrees or teeth off can the cams/crank be rotated and not cause damage? The book calls for the engine to be rotated several times to verify timing, I'm optimistic at this point that there was no damage done.

more later 8)

[metalguru]

Nice pics,
1 tooth on the crank would equate 1/2 tooth on the cams so in theory it should not interfere.
I have seen many 885s with this variation in timing, how many miles has yours done and was the chain drive side taught when you took the picture as the crank can move back when switched off. This was a common problem on the older 855 engines that used to atomise the sprag drive eventually.
I had an 885 in the w/shop where the cam chain tensioner had been removed and replaced allowing the timing to move 2 teeth on the crank with no ill effect, only the fact it would not run!

Best to check out the cam chain tensioner blades as these can self destruct and give the symptoms you describe, also the tensioner unit ratchet teeth havn't gone blunt.

[Mustang]

nothing will hit being off one or two teeth on the timing chain ......but if it jumped a tooth then you need to be paying some attention to the cam chain tensioner, and chain itself  , cuz that shouldn't have happened .

[blume]

Nice pics,
1 tooth on the crank would equate 1/2 tooth on the cams so in theory it should not interfere.
I have seen many 885s with this variation in timing, how many miles has yours done and was the chain drive side taught when you took the picture as the crank can move back when switched off. This was a common problem on the older 855 engines that used to atomise the sprag drive eventually.
I had an 885 in the w/shop where the cam chain tensioner had been removed and replaced allowing the timing to move 2 teeth on the crank with no ill effect, only the fact it would not run!

Best to check out the cam chain tensioner blades as these can self destruct and give the symptoms you describe, also the tensioner unit ratchet teeth havn't gone blunt.

62K+ miles, dealer recommends a new chain, I'll do that and the tensioner and blades while I'm at it. This is an early engine;  S/N- 84609, I'll look around for the sprag issue too.

I took the picture after I had rolled the engine over by hand- the chain was taut, but after I timed it last night I see an air gap between the cam gear teeth and chain, as if the chain is stretched way past limits, I'll be checking that also tonight before I do a leak-down check; no sense getting hasty and changing the chain and blades if the valves have been hit. Here's to hoping they are fine, although I found a half dozen 955 engines on Ebay with a quick look this morning; I may be doing a full swap if the "fix" costs start penciling out closer to buy-in on a complete engine.    

good to have a source of informed and informative  people here; thanks again!

[Timbox2]

................... although I found a half dozen 955 engines on Ebay with a quick look this morning.........................

Take care, lots of supposed Tiger 955 Engines out there which have come from Sprints, Daytonas etc, they may fit, but they aint the same, the early Sprint/ Daytona 955 is more like the 885 engine in design, just saying,  I spotted a bloke selling a Tiger 955 "Rear" subframe recently, thats clever I thought, they dont have one :lol:

[metalguru]

Sorry to mislead you on the 'early engines' what I refer to are the engine series before yours commonly known as Steamers, these had the troublesome sprags on the really early ones.

Mileage is not excessive for one of these so give it a compresson check, it is common to see daylight under the chain as it is of the Hyvo type which sits differently to a single row. The chain does look kinda shiny but nothing out of the ordinary that would cause a fatal stop. Did you notice if the oil lamp came on just before it stopped?

[metalguru]

................... although I found a half dozen 955 engines on Ebay with a quick look this morning.........................

Take care, lots of supposed Tiger 955 Engines out there which have come from Sprints, Daytonas etc, they may fit, but they aint the same, the early Sprint/ Daytona 955 is more like the 885 engine in design, just saying,  I spotted a bloke selling a Tiger 955 "Rear" subframe recently, thats clever I thought, they dont have one :lol:

+1 saw that aswell DOH