Would have definitely liked to see the cylinder and piston surfaces, it's odd that the centre wasn't burning oil if all were prepared the same, in my experience (reboring and honing cylinders since the mid 80's), vertical marks, if not a damaged ring on assembly, normally means abrasive particles in the cylinder, usually from inadequate cleaning of bores, or other components if they have been blasted. I used to bore undersize by about 0.002" to the finished size, and delapena fixed hone to clearance, an F6F stone is usually the finished cut with the cross hatch set to 30-40° included angle, for road use. . . if honed, cleaned and assembled correctly very little running in is required, just a couple of reasomably spirited rides and heat cycle checks. Tridents typically need head torque and valve clearance checked at least 3 times over the first few decent runs, to correctly settle. Parrallelism in the honed bore should not vary top to bottom by more than a couple tenths e.g. +/- 0.0001" to be a quality bore. Interested to see the findings, hope you used seals on the valve guides. Good luck, TTFN
A few comments from a T160 owner since 1979……….. The original pistons & rings are rubbish and other should be fitted. There is a lot of folklore around the best way to bed in rings and those who treat the bike to very gentle riding are setting themselves up to glaze the bores and have excessive oil consumption. The first few miles require fast running to seat the rings, gas pressure is required to do this as it is this that pushes the rings against the bore and helps remove the peaks of the honing marks to provide a slightly porous surface on the bore. Also don’t use high quality oil for the first few miles as this also prevents the rings seating properly ( both the moderately high running speeds and low quality oil are standard practice for break in of air cooled aircraft engines ). Two hours of running at 70 MPH should do the majority of the break in of the rings and at that point I would change the oil & filters with a move to a top quality oil at 500 miles. The real experts in the Trident world are Peckett Motorcycles in Brentford who can supply high quality engine parts at reasonable prices. They also have barrel hold down nuts that have a 7/16 bi-hex head rather than the standard 1/2 head, these nuts give extra clearance and enable a standard (bi-hex) spanner to be used.
To ease your gasket removal get some CRC gasket remover , it removes carbon as well. With newer style rings they like a finer cross hatch ,some quality ring sets give honing grade information , the old ring sets would use sunnen AN200 stones .Cheers
I appreciate that you have already sent the barrels off but for anyone in a similar situation this may be of some help. Top end engineers use a tool that measures the quality of the surface finish. The likes of Mitutoyo provide tolerances. This may sound like overkill for these engines but it’s a price I’d be willing to pay. If you wish I can add a link to a video of the item in use Kind regards
Hi folks I wasn’t going to put this link here but in the community section but I don’t think it’s in use. This video shows the importance of a torque plate and the use of the profilometer. Kind regards ua-cam.com/video/dx_KhaS0IFI/v-deo.htmlsi=JU8oZrPUksUEz0JG
It’s interesting to see how much the bores in this block are out of round. If this is deemed inappropriate please delete Kind regards ua-cam.com/video/dx_KhaS0IFI/v-deo.htmlsi=mPFYomH0BiOjz9Il
It will be interesting to see what your machine shop has to say. I agree with one of the comments below: Looks like the initial crosshatch was an aggressive cut/and or speed. I hope you can save this top end Chris.... By the way, one quick question: On your Tri-Core spanner and I have seen this before is the "AF" notation. Does that stand for Across Flats" and if so, it is the measurement of the actual flat across a bolt/nut?
Didn't these engines suffer from porosity through the cylinder head castings whereby lubricating oil was drawn into the combustion chambers through the cylinder head?
Thanks, I have heard of that, and it's a possibility, but as this was a running bike before and I don't think it was smoking that much then. But it's still something I need to check. 👍
The cross hatching looks horrendous....in 40yrs of engineering I've not seen anything like that. Take the barrel and pistons to a reputable engineer and get them to hone to the pistons. I would prepare yourself to the prospect of a rebore and pistons. Hopefully you won't. Cheers.
Yes, I think so, and also maybe Wassell ones? And although the newer Hepolite ones are supposed to be better than the very poor early ones I defo wouldn't fit them in my engines. So the only credible alternative is Omega in my opinion.
Would have definitely liked to see the cylinder and piston surfaces, it's odd that the centre wasn't burning oil if all were prepared the same, in my experience (reboring and honing cylinders since the mid 80's), vertical marks, if not a damaged ring on assembly, normally means abrasive particles in the cylinder, usually from inadequate cleaning of bores, or other components if they have been blasted.
I used to bore undersize by about 0.002" to the finished size, and delapena fixed hone to clearance, an F6F stone is usually the finished cut with the cross hatch set to 30-40° included angle, for road use. . . if honed, cleaned and assembled correctly very little running in is required, just a couple of reasomably spirited rides and heat cycle checks. Tridents typically need head torque and valve clearance checked at least 3 times over the first few decent runs, to correctly settle. Parrallelism in the honed bore should not vary top to bottom by more than a couple tenths e.g. +/- 0.0001" to be a quality bore. Interested to see the findings, hope you used seals on the valve guides. Good luck, TTFN
Let’s hope the place where you are sending the barrels & pistons are knowledgeable & competent enough to do a decent job for you. Fingers crossed.
Thanks. 👍
A few comments from a T160 owner since 1979……….. The original pistons & rings are rubbish and other should be fitted. There is a lot of folklore around the best way to bed in rings and those who treat the bike to very gentle riding are setting themselves up to glaze the bores and have excessive oil consumption. The first few miles require fast running to seat the rings, gas pressure is required to do this as it is this that pushes the rings against the bore and helps remove the peaks of the honing marks to provide a slightly porous surface on the bore. Also don’t use high quality oil for the first few miles as this also prevents the rings seating properly ( both the moderately high running speeds and low quality oil are standard practice for break in of air cooled aircraft engines ). Two hours of running at 70 MPH should do the majority of the break in of the rings and at that point I would change the oil & filters with a move to a top quality oil at 500 miles. The real experts in the Trident world are Peckett Motorcycles in Brentford who can supply high quality engine parts at reasonable prices. They also have barrel hold down nuts that have a 7/16 bi-hex head rather than the standard 1/2 head, these nuts give extra clearance and enable a standard (bi-hex) spanner to be used.
To ease your gasket removal get some CRC gasket remover , it removes carbon as well. With newer style rings they like a finer cross hatch ,some quality ring sets give honing grade information , the old ring sets would use sunnen AN200 stones .Cheers
Thanks. 👍
Ordered some today. 👍
P&M supplied NPR rings for my build, they rate them but I've yet to fire the engine for which P&M also lightly honed the bores.
If the rings were supplied by P&M they'll be top notch. 👍
I appreciate that you have already sent the barrels off but for anyone in a similar situation this may be of some help. Top end engineers use a tool that measures the quality of the surface finish. The likes of Mitutoyo provide tolerances. This may sound like overkill for these engines but it’s a price I’d be willing to pay. If you wish I can add a link to a video of the item in use Kind regards
Hi folks I wasn’t going to put this link here but in the community section but I don’t think it’s in use. This video shows the importance of a torque plate and the use of the profilometer. Kind regards
ua-cam.com/video/dx_KhaS0IFI/v-deo.htmlsi=JU8oZrPUksUEz0JG
By all means post the link. 👍
It’s interesting to see how much the bores in this block are out of round. If this is deemed inappropriate please delete Kind regards
ua-cam.com/video/dx_KhaS0IFI/v-deo.htmlsi=mPFYomH0BiOjz9Il
It will be interesting to see what your machine shop has to say. I agree with one of the comments below: Looks like the initial crosshatch was an aggressive cut/and or speed. I hope you can save this top end Chris.... By the way, one quick question: On your Tri-Core spanner and I have seen this before is the "AF" notation. Does that stand for Across Flats" and if so, it is the measurement of the actual flat across a bolt/nut?
Yep Across Flats en.wikipedia.org/wiki/Wrench_size
@@MrPnew1 Thank you for the reply and the link! Good information.
Didn't these engines suffer from porosity through the cylinder head castings whereby lubricating oil was drawn into the combustion chambers through the cylinder head?
Thanks, I have heard of that, and it's a possibility, but as this was a running bike before and I don't think it was smoking that much then. But it's still something I need to check. 👍
judging by the drastic wear to the bore it looks like you had zero ring gap
I'd be taking the whole lot back to whoever carried out that 'work' and see what their attitude is.
The cross hatching looks horrendous....in 40yrs of engineering I've not seen anything like that. Take the barrel and pistons to a reputable engineer and get them to hone to the pistons. I would prepare yourself to the prospect of a rebore and pistons. Hopefully you won't. Cheers.
@@peterchilton9700 l wish we could've seen the pistons and barrels in more detail with better lighting.
Apologies for the quality of the filming. I didn't realise how unclear it was until it was too late (after I'd sent the barrels off)
Ring gaps were preset and then checked by me before fitting.
What type of rings were they??
They were Omega rings. Apparently Goetze rings are now no longer being made, so Omega are the only practical choice.
Cheers,new hepolite rings are available?
Yes, I think so, and also maybe Wassell ones? And although the newer Hepolite ones are supposed to be better than the very poor early ones I defo wouldn't fit them in my engines. So the only credible alternative is Omega in my opinion.