Restoring & Modifying 1971 OIF TR120

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I had asked: "The Aerco kit is sold for unit 650s with and without a provision for 'oil feed to the tappets.' Could someone explain why they sell both versions for the same model-year range?"

I just found this website, which provides the answer: beginning in 1966, the Unit 650s had an oil feed hole to the exhaust tappets. So, I'd want the Aerco kit with the oil passage, which s7ns-noise sells for $720--actually quite a bit cheaper than without the oil feed.
 

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Whoa, wait a minute... the Morgo kit is $517, and even with shipping from the UK that's roughly $200 cheaper than the Aerco kit. Isn't the Morgo a competent kit? It seems to have several refinements that are desirable...

Also: it seems to me that 9:1 would be a better choice than 9.5:1, given the availability of 'premium' these days being in the low 90s octane level. Anyone have a different opinion?
 
9 bolt heads came with the unit motor in 1963. then the 9-1/2 bolt and 10-bolt head in 1973.

afaik, the only reason to run oil feed to the tappets is if you have a pair of antique cams that you simply must run. i think the last stock non -nitrided cams were in 68? or 69?

i plug the oil feed hole and run modern cams.

my 9.5 morgo has been trouble-free for 30 years. it has a twin plug head and i run 87 octane in it.
 
9 bolt heads came with the unit motor in 1963. then the 9-1/2 bolt and 10-bolt head in 1973.

afaik, the only reason to run oil feed to the tappets is if you have a pair of antique cams that you simply must run. i think the last stock non -nitrided cams were in 68? or 69?

i plug the oil feed hole and run modern cams.

my 9.5 morgo has been trouble-free for 30 years. it has a twin plug head and i run 87 octane in it.

Oh, okay... well if there's no benefit from the standpoint of longevity, there you have it. Thanks, Kevin.

I've put myself on the 'notify me' list for the Morgo 'standard' 9.5:1 kit.
 
The Aerco kit is sold for unit 650s with and without a provision for "oil feed to the tappets." Could someone explain why they sell both versions for the same model-year range?
I just found this website, which provides the answer
I'd want the Aerco kit with the oil passage,
No. If that website does not say when Triumph stopped fitting the oil feed hole, the website is not telling the whole story - Triumph stopped fitting the tappet oil feed (nitrided the camshafts instead) only a couple of years later - certainly well before 71 - because it abstracted oil pressure from the big-ends. :oops:

@speedrattle beat me to it ... :cool:
 
No. If that website does not say when Triumph stopped fitting the oil feed hole, the website is not telling the whole story - Triumph stopped fitting the tappet oil feed (nitrided the camshafts instead) only a couple of years later - certainly well before 71 - because it abstracted oil pressure from the big-ends. :oops:

@speedrattle beat me to it ... :cool:

Oh, well, then there's not only no need to retain the tappet oil feed hole, but a positive reason for deleting it--or plugging the oil feed hole in the tappet blocks. Good to know. I'm sure there's a thread on this website discussing how to accomplish that.

I also see that the Morgo kit has cutaways in the pistons for larger valves (if I wanted to go that route), and some other refinements. Seems like a great kit.
 
Note: the kicker cover screws are buggered up, but as I've never liked them I am switching to stainless allen socket head screws--which, by the way, are far cheaper than the OEM screws and available at home improvement stores.

Question: is there any good reason why Triumph uses a nice-looking acorn nut on the top stud but a nut on the lower one?
 
Triumph stopped fitting the tappet oil feed (nitrided the camshafts instead) only a couple of years later - certainly well before 71 - because it abstracted oil pressure from the big-ends. :oops:

youre right. my 72 T120 always used to have a flickering oil pressure light at idle. when i plugged the oil feed hole, the light stopped flickering. same oil pump. i did put in new bearing shells, but the others werent really worn
 
I also see that the Morgo kit has cutaways in the pistons for larger valves (if I wanted to go that route), and some other refinements. Seems like a great kit.

dont trust the pockets if you install larger valves. i had to have the ones in my morgo pistons cut larger to accomodate OS intake valves. but i may be out of date.

always clay the piston tops. i routinely enlarge the valve pockets on my stuff to get a minimum radial clearance.

ask people questions, too. morgo used to be the pre-eminent 750 kit, but i heard a rumour recently of a quality control issue. even so i would buy one from them right now for a sidecar tug im building if i had any money left.
 
dont trust the pockets if you install larger valves. i had to have the ones in my morgo pistons cut larger to accomodate OS intake valves. but i may be out of date.

always clay the piston tops. i routinely enlarge the valve pockets on my stuff to get a minimum radial clearance.

ask people questions, too. morgo used to be the pre-eminent 750 kit, but i heard a rumour recently of a quality control issue. even so i would buy one from them right now for a sidecar tug im building if i had any money left.

Okay, sounds good. Thanks.

I'll make a note re: the valve pockets and stick it in the box with the kit (which I'm buying whenever they get them back in stock). The Bridgeport just sits in a corner at my neighbor's shop, since he does virtually everything on CNC machines these days, so it's available for my tinkering with stuff like this.
 
Got the rough sanding done on the kicker cover, which was way worse than the timing cover. Also, it's got a @#$% load of radii to re-establish after the 100 grit initial work. The shot with it resting on the studs is after 100 grit; the one on my lap is after 150. Me wee fingers er a bit tired...

Hoping to get the wet sanding and polishing done before the box with the bushes (and the nifty con rods) arrives from the UK.

Meeting with the machinist Friday to write the routines and make the soft jaws to machine the prototype Wilwood caliper adapter. At this rate, I may actually ride the thing before the snow falls...
 

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. . . even so i would buy one from them right now for a sidecar tug im building if i had any money left.

Whoa, that's a coincidence. I've been sketching a design for a lightweight aluminum 'leaning' sidecar for the '51 FL, which has an unmolested frame with intact sidecar mounts. It would be a streamlined, strictly cargo carrier, though, because I'd like to be able to do grocery runs into the 'big city' (25 miles each way down two-lane blacktop) without driving a car.

Passengers would be stuck on a convertible pillion pad I've designed that fits over the rack on the rear fender. Just got some 4140 square bar in for some mods to the passenger foot peg mount, which attaches just aft of the tranny and angles up between the side-by-side shotguns (mount is not fitted in this pic).

You can see the front R/H sidecar loop mount just above the front of the footboard in this photo.

Oh, and here is a link to a guy riding a 'leaner' at a spirited pace in Europe. Pretty cool...
 

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Well, the con rod and other parts got here and... oh, yes, THE con rod. Singular. The photo showing a pair of rods isn't representative: they sell them individually (weird, for con rods). So, they are not cheaper, but more expensive than their competitors.

Ah, well... back it goes--together with a rusty, pitted kickstart bush, a tranny drain plug whose level tube is far too long, and two brand new aluminum inspection covers with defective threads.

So much for my previously favorable experiences with Draganfly in the UK...
 
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