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Let's stick to two wheels, plenty of car forums out there.
 

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Er... a back on subject.....
As you can see its a fairly deep mark likely caused by a seized ring in a rusty bore from standing a long time though I'll never know if that's the case. Also plenty of score marks down both bores one pretty deep. Although not a total disaster the new rings would struggle to bed in even if it were honed smooth and I dont want it using excessive amounts of oil after the rebuild.
Cylinder barrel now now with a machine shop to check and re-bore hopefully one size up from present @ plus .040" but waiting for thenm to confirm before I purchase and supply new pistons.
Who are you using for parts?
 

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Discussion Starter · #23 ·
Who are you using for parts?
Hi Ricky lookin all over the place for best quality for the best price. Found a website called montys classic motorcycles shop . Good prices and they seem to have most of what I need.
On to the cylinder head etc.
Some progress some steps backwards. Waiting for the man to contact me regarding the barrel and what oversize pistons he will require. I guess he will put a light cut down the worst bore to give him an idea.
Once again a part that was deemed as good by the previous engine shop is not as expected. The cylinder head face is not true and has a .003" - (.08mm) dip in the center. See pics. Not sure if this can be tolerated and taken up by the gasket as there seems very little seating area to remove before you would be into the first cooling fin. Two types of head gasket as I understand. Old copper type and a later style composite.
I could see a pattern mark from where the composite gasket was last fitted and used. I polished the face with machined faced heavy metal bar. You can see the low point in the center.
272800
272801

Any expert opinions gratefully received.
 

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Hi Sump....what do I call you? I go by Dick, but Ricky is the usual forum default, as the swear filter won't accept Dick. I was going to suggest Monty's better prices than Hyde, Classic bike shop is OK and there is also feked.com,
It's common for heads to have a warp you may get away with that and an annealed copper head gasket and some wellseal, or you could use the old sheet of plate glass and some grinding paste or just get 10 though skimmed off it.
 

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Hi Sump....what do I call you? I go by Dick, but Ricky is the usual forum default, as the swear filter won't accept Dick. I was going to suggest Monty's better prices than Hyde, Classic bike shop is OK and there is also feked.com,
It's common for heads to have a warp you may get away with that and an annealed copper head gasket and some wellseal, or you could use the old sheet of plate glass and some grinding paste or just get 10 though skimmed off it.
Well I'm no expert, but .003 is not very significant. Flat dress it, n use a nice copper gasket w copper coat on it. Torque in 3 steps, n then retorque thrice w heat cycles n it'll not leak till its pulled to replace the wore out rings next time.... be aware of rockerbox "crush" look at the areas where the head bolts bear down on the inner area or the rocker boxes. It's been suggested and many have had great service from a washer under headbolt cut to just clear inside rockerbox. Hols better, by spreading out holding force. The 2 piece head bolt affairs on these later engines r an area of particular irritation. The tappets.... if you've got both std n r tappets, try both with a degree wheel. See which gives you the better valve timing, and degree in the cams 104- 107 cl. It'll be one smoothe idling ol girl, easier starting , less tempermental. Or less brittle as I've described... made a real difference in mine so she brakes nice, runs pretty smoothly. There's a lot of info hearabouts concerning degree ing in yer cams. Be careful w shaving the head, can cause head warpage. How? Ok brit twin 101.. never figured in pushrod tube length, o ring crush, valve train geometry. Picture all the parts assembled n I'll clear up quick.... the make over thickness copper gaskets. Hop you have fun, enjoy n get into the wind n smile. B
 

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Discussion Starter · #26 ·
Hi Sump....what do I call you? I go by Dick, but Ricky is the usual forum default, as the swear filter won't accept Dick. I was going to suggest Monty's better prices than Hyde, Classic bike shop is OK and there is also feked.com,
It's common for heads to have a warp you may get away with that and an annealed copper head gasket and some wellseal, or you could use the old sheet of plate glass and some grinding paste or just get 10 though skimmed off it.
Well I'm no expert, but .003 is not very significant. Flat dress it, n use a nice copper gasket w copper coat on it. Torque in 3 steps, n then retorque thrice w heat cycles n it'll not leak till its pulled to replace the wore out rings next time.... be aware of rockerbox "crush" look at the areas where the head bolts bear down on the inner area or the rocker boxes. It's been suggested and many have had great service from a washer under headbolt cut to just clear inside rockerbox. Hols better, by spreading out holding force. The 2 piece head bolt affairs on these later engines r an area of particular irritation. The tappets.... if you've got both std n r tappets, try both with a degree wheel. See which gives you the better valve timing, and degree in the cams 104- 107 cl. It'll be one smoothe idling ol girl, easier starting , less tempermental. Or less brittle as I've described... made a real difference in mine so she brakes nice, runs pretty smoothly. There's a lot of info hearabouts concerning degree ing in yer cams. Be careful w shaving the head, can cause head warpage. How? Ok brit twin 101.. never figured in pushrod tube length, o ring crush, valve train geometry. Picture all the parts assembled n I'll clear up quick.... the make over thickness copper gaskets. Hop you have fun, enjoy n get into the wind n smile. B
Call me Pete Ricky Thanks for the other links.
Quite a few parts store's on line Mont'ys actually only and hour drive away from me but they seem to be a reliable source with pretty good prices. Think your right about the head. Being used to building mostly water cooled and more sophisticated multi cylinder engines threw me into basic engineering rules mode.
No doubt it would be ideal to have a perfectly flat head but I believe this configuration wont be compromised by a little dip in the center of the sealing surface when the firing ring areas look smooth, flat and undamaged. However I have rubbed the face back a bit with an old flat and heavy machine shop parallel and some 600 grit wet and dry and have got it down to under 0.002" which I'm happy with.
On Montys parts list there is a dedicated composite head gasket for this era T140 so not sure whether to go with that or a copper one..
 

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Discussion Starter · #27 ·
Well I'm no expert, but .003 is not very significant. Flat dress it, n use a nice copper gasket w copper coat on it. Torque in 3 steps, n then retorque thrice w heat cycles n it'll not leak till its pulled to replace the wore out rings next time.... be aware of rockerbox "crush" look at the areas where the head bolts bear down on the inner area or the rocker boxes. It's been suggested and many have had great service from a washer under headbolt cut to just clear inside rockerbox. Hols better, by spreading out holding force. The 2 piece head bolt affairs on these later engines r an area of particular irritation. The tappets.... if you've got both std n r tappets, try both with a degree wheel. See which gives you the better valve timing, and degree in the cams 104- 107 cl. It'll be one smoothe idling ol girl, easier starting , less tempermental. Or less brittle as I've described... made a real difference in mine so she brakes nice, runs pretty smoothly. There's a lot of info hearabouts concerning degree ing in yer cams. Be careful w shaving the head, can cause head warpage. How? Ok brit twin 101.. never figured in pushrod tube length, o ring crush, valve train geometry. Picture all the parts assembled n I'll clear up quick.... the make over thickness copper gaskets. Hop you have fun, enjoy n get into the wind n smile. B
Thanks Brent some really good info there from someone with much more experience of these machines than myself though Ill leave the valve timing etc for another day to consider when I reach that stage Interesting stuff though and this bike was plagued with starting issues that were never resolved..
 

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Discussion Starter · #28 ·
Curios now regards cam timing and radius of cam followers. Three keyways on both cam wheels and I have the basic timing marks and procedure I was going to adhere to but there's obviously more you can do for more accurate valve timing?.
Would need to bee explained in a little more detail to grasp the principals. (y)
 

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just a little point you might find interesting, a friends dad worked for Triumph at the Meriden factory from the mid 50's till he retired just before they shut down & he told me his dad said that when Triumph had the barrel castings delivered, before any machining was done they were left in the factory yard for a year to stress relive them through weathering, then they were machined & liners installed, after which they were again left to weather for a few weeks before being bored to size, the idea was any micro rust pitting in the bore would hold a little oil to help keep it all nice n slick....it makes me wonder if any of the repop cylinders you can buy have gone through this process ?.... Triumph obviously did it for a reason, & not just a fast production & quick profit like todays manufacturers do.
 

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Discussion Starter · #30 ·
just a little point you might find interesting, a friends dad worked for Triumph at the Meriden factory from the mid 50's till he retired just before they shut down & he told me his dad said that when Triumph had the barrel castings delivered, before any machining was done they were left in the factory yard for a year to stress relive them through weathering, then they were machined & liners installed, after which they were again left to weather for a few weeks before being bored to size, the idea was any micro rust pitting in the bore would hold a little oil to help keep it all nice n slick....it makes me wonder if any of the repop cylinders you can buy have gone through this process ?.... Triumph obviously did it for a reason, & not just a fast production & quick profit like todays manufacturers do.
Hi Pete glad you picked up this thread again.. That's interesting . I have heard of this process in the manufacture of cast iron blocks etc I believe I read some time ago BMW used to do the same for their car engines at one time. Modern production high turnover methods in the modern world a bit different I reckon and the repro barrells I doubt are "weathered". Modern oils, filtering systems and manufacturing/high quality materials have made a massive difference to engine longevity mind you.
Rarely have I seen excessive bore wear on a modern car engines like you used to 40 years ago.
 

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A quick triumph cam timing search will get you more information than you need on tweaking the cams, some of it from land speed record holders. Very interesting.
 

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As said Pete, have a bit of a search and draw your own conclusions and decide what would be the best option for you own use, and be prepared to spend a few hours with lumps of platercine and degree disc.
 

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Discussion Starter · #33 ·
Cheers Ricky. Ill take a look zat some point but just really wan to get it all running sweet and as oil tight as standard. Still waiting for the barrel back from the machinist hes been busy and waiting on pistons set up in his machine and doesn't want to disturb or move anything So basically just been fiddling around with cleaning and making sure mating surfaces are flat etc which brought me to checking the sealing agreas of the pushrod tubes in the head. I had assumed the tubes were both set at right angles to the head surface but the inlet side looks to be cocked outwards when pushed fully home which surprised me. I can't see how this could be wrong which would mean the guide block must also be set at an angle.
Have a look at the pic interested to hear what you think. (y)
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Oh bonus, you could put a degree wheel on the crank, n degree in the cams without the cyl on, but better to try it w cyl barrels on n tappets in. Using an indicator on the tappet n wheel on crank. That way the timing gears can be all setup b4 dropping into frame , then but top end on in frame, easier than grunting the whole lump in almost one piece...
 

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Call me Pete Ricky Thanks for the other links.
Quite a few parts store's on line Mont'ys actually only and hour drive away from me but they seem to be a reliable source with pretty good prices. Think your right about the head. Being used to building mostly water cooled and more sophisticated multi cylinder engines threw me into basic engineering rules mode.
No doubt it would be ideal to have a perfectly flat head but I believe this configuration wont be compromised by a little dip in the center of the sealing surface when the firing ring areas look smooth, flat and undamaged. However I have rubbed the face back a bit with an old flat and heavy machine shop parallel and some 600 grit wet and dry and have got it down to under 0.002" which I'm happy with.
On Montys parts list there is a dedicated composite head gasket for this era T140 so not sure whether to go with that or a copper one..
Copper gaskets inc. sell rocker box gaskets whish are better than stock because you have head bolts going through the boxes.
 

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Discussion Starter · #38 ·
Thank you for confirming that Mike. The sealing properties were never great and this one had silicon gasket sealer all over the tubes where someone had tried to stop the oil leaks.
Just something I needed to check up on. One is chrome plated and the other is aluminium which looks a better made tube than the steel chrome plated one. Just two black "o" rings - one top one bottom with "wedding rings" on the bottom.
So many different designs over the years this being the last in the line I believe.
 

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I have used copper head , rockerbox and cylinder base gaskets to seal up , and restore the origional valve train geometry. Copper gaskets Inc is a fine outfit. Your cyl head looks to be un shaved. The pushrod tubes are as you observed variably interesting. I went thru a box of them to find "pairs" of same length to use on my 64, 65, and my 79 engines as there's alot of variations in length. Chrome don't get ya home is my first criteria. Appearance is secondary. You seem to be on a very good path in your rebuild. There's another here rebuilding a 750 oif. I gave him some info about using other carbs. But I was slightly behind in my info as they now make a concentric right sided. But I'm a frigging dinosaur and prefer monoblock carbs as they r dead simple , easy to tune, stonehenge easy to clean . If I can help in any way feel free to msg me.
 

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Discussion Starter · #40 ·
Thank you Brent . (y)
Just had a message back from the machine shop who have the barrel and an old piston. Hes run a light cut down both cylinders one cleared easily the other has a small mark left that he hopes will hone out. Also says the bores are oval and misshapen and suggested was quite common but doesn't want to lose a life with plus .060" cut (currently plus 020") if he can help it. Not sure where the mark is as yet but hope it will come out with the final cut and hone.
The rocker top cover plates I have faced off with a flat face and emery sheet after putting a straight edge across every bolt hole "ear" had been over tightened and distorted the face leaving big gaps for the gasket to seal so hopefully no oil leaks from that area.
 
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