October 2026
1975 Triumph T160 Trident 830
My own fabulous beastie which I bought brand new in 1977 while living in Gladstone, Queensland. Was saving for a Laverda Jota but saw this first and it was love at first ride.
I wore the bores out by 41000 miles having given it one set of new rings at 25000 - and that was because it had faulty oil rings from new. By now I was back home so figured I had the tools to do it justice.
Now with the mileage you see it had suddenly developed some smoke at idle, and I have recently had another Hyde T160 which had had a Hyde supplied piston break below the oil ring, so I did not want to keep using mine until I had found what was up.
Current job is stalled awaiting parts, so today I thought why not.
I actually love working on my bikes because they have everything that was meant to be there - where it should be - and this bike has only received an 830 Hyde barrel and piston kit, so it is pretty much stock everywhere else.
At the time I fitted the 830 kit I had just had to cancel my order with Les Williams for a T160 Legend, because Les could not find a T160 donor bike in the UK, and rather than send this one both ways I decided to use a few Legend bits and keep the original looking bike. The 830 kit was pretty much the same price as it would have cost me to rebore my 750 and fit new pistons back in 1991, although I did send the head to Les for gasflowing.
So it has come apart very agreeably thus far. The exhaust was a one-off built by Ross Holliday for someone else who then didn't need it, and it is a most beautiful piece of kit. Besides giving me all the cornering clearance I can use it comes off and goes on with no stress at all - it just fits together so well.
It also has the original looking four header pipes which was a distinctive feature I wanted to keep. They feed into a narrowed collector and include larger outer headers that are adopted by many as they improve breathing. Ross told me it would run richer when I fitted it so I would need to lean it a bit, and he was spot-on. Efficiency is a good thing when it comes to gasflow.
I just had to text him before and thank him for his excellent work once again...
The barrels look fine and dandy and will be the next thing to come off. I had needed to repair them because a pillar stud stripped its thread five years back, and Glen was able to supply me with a specially made 7/16" item that also has an extra 1/4" of thread that was previously unused space at the bottom of the original thread hole. The cylinder liners were too large in diameter for me to use my usual 1/2" oversize pillar studs so this was a brilliant cure.
When I ordered my Hyde kit in 1990 we were about to lose our leaded petrol, so I opted for the slightly lower compression 8.7/1 piston option. If these pistons are still sound I will hone the bores and fit a new set of rings, but if it needs a rebore then the CR is going to go up a bit.
If they do turn out to be similar to the type that had failed on the other bike I will bore it anyway - happy with either outcome as long as the smoke ceases..
The cylinder head was given the treatment when the barrels were repaired at 63000 miles, so the new valves and guides have only covered 800 miles since, and should be ok for some years yet due to the diminishing use the bike gets. However, I intend to fit a set of the original type valve adjusters if I have a good enough set amongst my spare parts. Those adjusters gave the best mileage between guide replacements due to their flat footprint on the end of the valve stem which resulted in much less side thrust than the currently available point contact mushroom style do.
The oversize head gasket for the T120 71mm pistons is a very expensive import from the UK, so I shall just anneal this one and use it again. It has certainly proved to be oiltight and gastight since that last engine work was performed, and it is easy enough to anneal it again. The Hyde liners have a raised ridge which is a neat fit through the copper gasket, and this assists the sealing of the cylinder to head joint. It would have been a real plus if it had been a factory design feature.
The beauty of the aluminium rocker box gaskets - besides giving a far more stable joint than the original types - is that they too can be reused numerous times. All they require is a good clean up and the removal of any burrs on their edges. I use a light smear of silicone sealant on both sides of them which is easy to clean off when preparing them for their next tour of duty.
The lack of mileage since the last assembly also means that all the pushrod seals are still in excellent condition and will be reused also, although the amount of necessary seal compression will be checked and adjusted if found wanting. I doubt that it will.
So - the jury is still out as to what is going to be done until the bores and pistons can be carefully examined and measured. Their wearing surfaces have covered just over 20000 miles since fitting 25 years ago, so I figure a set of rings is the most likely outcome. I will just be greatly relieved if the pistons are not showing any signs of distress otherwise and not worn enough to require replacing.
Once again - and also considering I run synthetic 20W/50 oil - I reckon there is a very good chance.
Pretty impressed with how clean everything still looks inside the crankcase considering the last assembly was 5 years ago. Shiny conrods are happy conrods...
