1983 Triumph T140W 750 TSS; 8 valves & electric start!

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Hello again Mike,

Great to catch up again. :y2: Where have you been hiding.....hopefully roaring around on the TSS.

Prior to my purchase, new stainless valves and hardened seats were fitted in the US, so as to run the bike on unleaded petrol. Unsure whether the original rings were replaced, however the cylinders were freshly honed and I can only assume this was done because new rings were fitted. When I received the bike, with its major oil leak from the bent exhaust push rod tube, I stripped the engine and discovered this recent work. The more I think about it, and judging by the newness of the head work and cylinder hone, I would suggest it did a couple of runs around the block, before I purchased it......sucker. BLUSH

Are you experiencing any oil consumption issues, oil at the breather in the right air filter box, increasing oil leaks and the real give away, engine oil migrating to the gearbox via the gearshift cross over shaft. Removing the inspection cap adjacent the clutch cable and having a look in with a torch will reveal this. If its black and horrible in there, then crankcase pressurization is a problem. Not a real smart idea with the cross over shaft not having any sealing arrangement on it.

Another problem I discovered, is movement of the tappet block in the aluminium barrels. The locating bolt does not bottom out on the tappet block and my exhaust tappet block was quite a loose fit in the barrels. This was creating an increasing oil leak as the tappet block was moving and pumping oil out. The fix was to fit the tappet blocks in with Loctite 660 quick metal which is used on worn shafts etc. I also hand fitted new locating bolts so that they bottom out on the tappet block recess to mechanically secure them. The quality of the aluminium castings of the heads and barrels is not great. You will notice porosity in these castings, which makes them soft. The crankcases etc are a different story....much better quality.

When this wet weather dries up, hopefully the TSS will be in action and I'll be able to ride with soul again. The Tiger doesn't quite have that quality. It does everything else real well though.

To sum up, I would say that my bike did not have the original rings in it when I purchased it.

Enjoy riding your TSS

SD....the sun will come :y54:


Hi SD,

I have been on the bike a bit but not as much as would have liked, just about covered a 1000miles since she went on the road. I've not noticed any significant oil consumption and although my front push rod tube leaks (more of a weep really) i check the level before every ride and have not needed to top up the oil. In saying that, i'm not riding her hard and the first highway run was 2 weeks ago, i'm being respectful of her age and the general unknown durability of the TSS engine. If I had done as you have and carried out a complete overhaul, i would be a little more confident in what was going on inside and less worried about a major failure. The many oil changes in my 1000mile (now 4) have not produced any worrying debris (apart from the 1st one) so that gives me some peace of mind. Then of course i read your post and find that even after a meticulous engine rebuild, sh*t still happens:y13:


I've just about sorted the carb problem (took your lead re the cold start gaskets), which made an instant noticeable difference. I also changed the o-rings as one was perished and hard. Still got a very slight hunt/surge but that might tune out or it may be the diaphragm?

Some pics of my excellent work...

IMG_0534.jpgIMG_0535.jpgIMG_0536.jpgIMG_0537.jpgIMG_0539.jpgIMG_0541.jpgIMG_0544.jpg

That highway run was to the Malany Swap, wet and muddy but i did pick up a couple of spare flashers for $10, there of BMW's if you did not already know. The TSS did get a bit of attention while parked and i had 20min Q&A section with a few of it's admirers. Nice!

Cheers

Mike
 
New piston rings arrived.....arrr wrong ones. I was supplied with the 4 valve motor rings which have the same diameter, however the thickness is different and they do no fit in the ring grooves. Supplier has a set of +020 inch 8 valve rings, however the bore on my engine is standard. Considering using the +020 rings and grinding back the ring ends to achieve the correct ring gap.

Your thoughts gentlemen.

ps. I am still hunting for standard size rings, which is my preferred option.


"New piston rings arrived....arrr wrong ones" Hey "Sea Dog" that "arrr" is a dead give-away that you used to be a pirate:y2:
 
"New piston rings arrived....arrr wrong ones" Hey "Sea Dog" that "arrr" is a dead give-away that you used to be a pirate:y2:

Arrrrr.....still plenty of salt in the veins.

Great to hear you have nearly sorted the surging. I admire your excellent work :y2:

I would say you have a good engine if there is no oil consumption after 1000 miles. What oil are you using?

I also am respectful of the old girls age and certainly travel at the posted speed limits and take my time getting there to look after things. The bottom end is really strong and should last forever. Above the pistons.....great design, however the aluminium castings a little soft.
 
Arrrrr.....still plenty of salt in the veins.

Great to hear you have nearly sorted the surging. I admire your excellent work :y2:

I would say you have a good engine if there is no oil consumption after 1000 miles. What oil are you using?

I also am respectful of the old girls age and certainly travel at the posted speed limits and take my time getting there to look after things. The bottom end is really strong and should last forever. Above the pistons.....great design, however the aluminium castings a little soft.



Now i'm not saying no oil consumption.. just not noticed anything significant. This is probably due to the fact that i'm changing the oil so often that there is no time to consume any:y2:

As for the oil I'm using, it's just basic 20/50 low detergent stuff from Kmart. I'd read that putting modern oils with all their cleaning agents in classics can cause stuff to be dislodged and block up oil ways... not a problem if the engine has been rebuilt and cleaned out of course. The oil in the bike when it arrived was new or at least fresh, I only ran it a few times before draining and the goop(see previous posts) came out with it. The other 3 oil changes have not produced any worrying icky stuff, so far!

This is my theory, while a modern oil may last a lot longer before it starts to break down and stop doing what it's meant to do and there is no real filtration system in the T140 (unless you add one of course) so cheaper oil changed every (probably start going out to 500-1000 miles between drinks) is better than leaving in modern stuff for? ( Triumph service intervals are 1500?miles).

I got the idea from an article in Classic Bike (UK Mag) where some the deemed experts of the time gave their views on the merits of modern oils in classics, there was some technical stuff that i can't quite recall( something to do with build tolerances now and then) also the old clutches don't like modern oils and can slip.


I'm hoping to get a few miles in during the holidays, also need to change the oil (AGAIN!) and tinker with the carbs a bit more. Although the "TO DO" list my wife has given me wil not leave much timeSAD

Any luck with finding new rings?

Cheers

Mike
 
Yeh...the wife's to do list certainly encroaches on toy time. I believe you are on the correct track with oil for your engine as it has never been apart. The issues I have experienced with mine are by and large caused by the work carried out previously. Still it's an interesting journey sorting it all out.

I have in my possession a set of standard, original rings. Found them at Eades Motorcycles in Sydney. Interesting, I will need to grind the ends to achieve the correct gap. When time allows, I will get on with putting the barrels and head on and enjoy the classic ride.

:y54:
 
... Interesting, I will need to grind the ends to achieve the correct gap.

That is oftimes typical; I've found that when inexpensive rings are "sized to the oversize" (from the factory), the end gap is too great and they smoke. I like custom fitting each ring to mid-spec in the exact bore it will reside in.
 
Hey Mike,

Nice score!!:y45:

Where is the rest of the bike. Could be good for more parts.
Great idea to preserve the original parts of your bike ....will have greater value in the future.

Cheers

SD
 
Hey Mike,

Nice score!!:y45:

Where is the rest of the bike. Could be good for more parts.
Great idea to preserve the original parts of your bike ....will have greater value in the future.

Cheers

SD



This is the rest of the bike, check out the interesting engine upgrades..

Type this to eBay UK not an auction but a classified ad. "Triumph TSS 8 Valve 750 Bonneville, T140W matching frame and engine numbers"

I paid more in freight than i did for the parts, and I only wanted the RH side cover!

Cheers

Mike
 
This is the rest of the bike, check out the interesting engine upgrades..

Type this to eBay UK not an auction but a classified ad. "Triumph TSS 8 Valve 750 Bonneville, T140W matching frame and engine numbers"

I paid more in freight than i did for the parts, and I only wanted the RH side cover!

Cheers

Mike

Hi Mike,

Had a look at his TSS on Ebay. Now that would be an engine to get. Totally bullet proof. I like the way he has kept the bike looking very understated and classic. I would say it would have some serious go in it. :y2:
 
Hi SD,

Yes I agree, the bike is well done and the Harris style front guard and side covers definatly suit the bike, interesting about the aftermarket pushrods tubes machined to fit exactly and now no leaks? I would like to know what aftermarket ones they were.. and sounds like the leaky PR tubes are the norm...

Not sure what the engine bolt conversion thingy is about? and the inserts in the head suggest they actually had a porosity problem with it.

You should send them a question on eBay asking where they got the piston rings..... how are you going with that little issue.

Cheers

Mike
 
Hi SD,

Yes I agree, the bike is well done and the Harris style front guard and side covers definatly suit the bike, interesting about the aftermarket pushrods tubes machined to fit exactly and now no leaks? I would like to know what aftermarket ones they were.. and sounds like the leaky PR tubes are the norm...

Not sure what the engine bolt conversion thingy is about? and the inserts in the head suggest they actually had a porosity problem with it.

You should send them a question on eBay asking where they got the piston rings..... how are you going with that little issue.

Cheers

Mike

Hi Mike,

Have now got OEM std rings and gapped ready to go. One of the new compression rings supplied also had a flat spot in it, however no where near as bad as the one that caused me the problem. Had to get it replaced which took a while.

Followed up on the copper rocker cover gaskets and should have them next week. Also having copper head gasket rings and exhaust manifold flange rings made up by the same bloke.

The problem with the standard head gasket rings are they are made of folded sheet steel with two voids in cross section filled with a compressible fiber. These compress down 1mm over a period of time and cause havoc with the push rod tube clearances. I will assemble the barrels and head with the copper head gasket rings, measure the push rod tube clearances, then get high temperature O rings to suit allowing for the 0.040 thou squish recommended in the workshop manual. Hopefully another problem solved. Will let you know how it goes.

The head nut conversion is for the head nuts inside the rocker covers and are designed to stop oil leaking down the head studs and seeping out between the head and barrels (Problem with using Cooper rings rather than a head gasket). The standard set up uses an O ring under the head nut and steel washer. Contemplating whether this is good enough on the long term.

The brass scull inserts in the head are quite an amazing piece of engineering. These are usually used in dragster engines using extraordinarily high compressions. Would make the TSS head bullet proof.

With current commitments, looking at having the TSS running in a about 3 weeks.
 
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