Looks awesome!
Restoring & Modifying 1971 OIF TR120
- Thread starter NM Bonny
- Start date
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Thanks, Man! Your effort was what emboldened me to try the aluminum fairing, so I might not have done it without you forging the way.
So, the Viton gas cap gaskets came in and they look nice. I got both thicknesses, so we’ll see which works best with my OEM cap.
I’m hoping it was the depression that has already appeared in my new cork gasket that is allowing fuel to leak out when the tank is close to full—rather than the cap’s vent. But we’ll see whenever the 35 mph gusts die down and it’s a nice riding day again...
Update: yup, it was the new cork gasket. These Viton seals work wonderfully. Not a dribble after riding ~45 miles into and around town today. The 1/8” was too thick, but the 3/32” was perfect. The OEM cap is nice and snug but still no problem going on and off to fill up. I can heartily recommend these!
I’m hoping it was the depression that has already appeared in my new cork gasket that is allowing fuel to leak out when the tank is close to full—rather than the cap’s vent. But we’ll see whenever the 35 mph gusts die down and it’s a nice riding day again...
Update: yup, it was the new cork gasket. These Viton seals work wonderfully. Not a dribble after riding ~45 miles into and around town today. The 1/8” was too thick, but the 3/32” was perfect. The OEM cap is nice and snug but still no problem going on and off to fill up. I can heartily recommend these!
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BTW - the pads on the DIY front 11.5” disc conversion have fully bedded in… and the brake is simply amazing. The bike stops F-A-S-T with very little effort, and there’s good modulation, too. The only time I use the back brake is for steep hill starts and of course cornering on loose surfaces, wet pavement, etc.
Quite possibly the single best mod I’ve done to the bike.
Quite possibly the single best mod I’ve done to the bike.
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Two questions. I’m hoping someone can clue me in to what is the normal range for these bikes:
One - The rocker cover bolts seem to loosen a smidge after several hours of running--together with the clamps holding the ‘manifolds’ for the Mikunis (look to me like just slices of fuel filler hose). I’m obviously more interested in knowing whether it’s normal for the rocker cover bolts to want to loosen, as my ’51 FL, aka The Paint Shaker, also has a 360-degree crank but doesn’t do that.
As for the carbs, I plan on fabricating some lightweight supports. Right now, they essentially dangle on the ends of the ‘manifolds,’ and unlike the similar hoses for the Bings on the Beemer, the air cleaners do not help support them...
Two - Oil consumption. What is typical for a Unit 650 in decent running shape?
One - The rocker cover bolts seem to loosen a smidge after several hours of running--together with the clamps holding the ‘manifolds’ for the Mikunis (look to me like just slices of fuel filler hose). I’m obviously more interested in knowing whether it’s normal for the rocker cover bolts to want to loosen, as my ’51 FL, aka The Paint Shaker, also has a 360-degree crank but doesn’t do that.
As for the carbs, I plan on fabricating some lightweight supports. Right now, they essentially dangle on the ends of the ‘manifolds,’ and unlike the similar hoses for the Bings on the Beemer, the air cleaners do not help support them...
Two - Oil consumption. What is typical for a Unit 650 in decent running shape?
Ducman
Active Member
NM Bonny,
ONE: I have never found the rocker cover fasteners on my 1972 T12RV to loosen. Just asking, but are you the original owner? If not, perhaps the threads in the head have been damaged and the fasteners fit a little loose. Consider using a "light" amount of thread lock.
TWO: Does the bike still have the chain oiler? With new chains and chain lube, I eliminated the chain oilers and do not have any oil loss. How many miles are on the engine?
ONE: I have never found the rocker cover fasteners on my 1972 T12RV to loosen. Just asking, but are you the original owner? If not, perhaps the threads in the head have been damaged and the fasteners fit a little loose. Consider using a "light" amount of thread lock.
TWO: Does the bike still have the chain oiler? With new chains and chain lube, I eliminated the chain oilers and do not have any oil loss. How many miles are on the engine?
Lordmac
Well-Known Member
I do not have that problem with my T140V. Do we know what gaskets material are being used, both head and valve-covers?
The clues are in the thread title (although @NM Bonny meant "T120R", not "TR120") and his photos in the thread ...
Fasteners: I’m not the original owner, so don’t know the condition of the threads. Though, they seem to tighten well when I pull (gently) on them and when I R&R’d the rocker covers to reseal them when I bought the bike. I will try your suggestion of blue loctite if the issue repeats.
Chain oiler: hmmm… I need to look into that—which would be a wonderful solution, if that’s the case. I didn’t realize the Unit 650s had one! What’s involved in closing the final chain oiler off?
I don’t know the engine’s mileage. Someone had scribbed a note up front in the Chilton’s manual about a rebuild—and the compression was not bad (perfectly even) when I bought it (see pics). Dunno if it’s drifted up any due to rings re-seating after being run regularly again. My understanding is it had been sitting for a long time when I bought it.
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I purchased standard valve cover gaskets when I R&R’d them upon buying the bike, to reseal them (looked like they’d been seeping a bit).
I did not disturb the head gaskets, due to the decent compression (previous post) and no leakage at all. So, don’t know the material there.
Looking at the lubrication diagram, I don’t think the OIF bikes had a final drive chain oiler…?
All,
It would help understanding if the same components were referred to by the same names, ideally the ones Triumph used:-
Your photos of your bike show it does not have "rocker covers"? Your bike does have:-
. "Inlet rocker box" and "Exhaust rocker box"; each "rocker box" contains two rockers, a spindle on which the rockers rotate and several different washers on the spindle to space the rockers within the rocker box so the threaded "Rocker adjuster pin" is over the end of a valve.
. Each rocker box has two circular "Inspection caps" screwed into it, one cap over each Rocker adjuster pin.
. Early 72 650s have the same as 71 650s - circular, originally slotted, "Inspection caps" screwed into each "rocker box", one over each "Rocker adjuster pin".
. Later 72 650s have different "rocker boxes", both "Rocker adjuster pins" in a given box covered by one long oval "Inspection cover" secured to the box by four bolts.
. No T140 had the same "rocker boxes" with "Inspection caps" as a 71 T120R.
. Your bike's "rocker boxes" and "Inspection covers" are at least similar to those on later 72 650s - all 750 twins have the same single long oval "Inspection cover" secured to each rocker box, early by four bolts, later by six bolts.
Better at helping to prevent "Inspection caps" loosening due to vibration are rubber O rings like these,
the thicker the better. I am not sure if Meriden eventually made O rings standard (part numbers were not always changed when circular fibre "Joint washers" were changed to O rings) but "Inspection cap" O rings have been available certainly in the UK for a long time.
Difficult to tell from your photos if your bike has original type "Inspection caps" with two slots at 90 degrees to one another? If it does:-
. The caps should have serrated edges, your bike's rocker boxes are fitted with an E4609 "Locking spring" engaging with the serrations in each "Inspection cap"?
. Aftermarket "Inspection caps" are available with a large hex instead of the two slots. If nothing else stops your bike's "Inspection caps" loosening, you could fit these with a small hole drilled in the side of each hex, ziptie the caps to together?
Thankfully Meriden had started to remove standard chain oilers even before the oif.
It would help understanding if the same components were referred to by the same names, ideally the ones Triumph used:-
Your photos of your bike show it does not have "rocker covers"? Your bike does have:-. "Inlet rocker box" and "Exhaust rocker box"; each "rocker box" contains two rockers, a spindle on which the rockers rotate and several different washers on the spindle to space the rockers within the rocker box so the threaded "Rocker adjuster pin" is over the end of a valve.
. Each rocker box has two circular "Inspection caps" screwed into it, one cap over each Rocker adjuster pin.
Depends what your bike has:-
. Early 72 650s have the same as 71 650s - circular, originally slotted, "Inspection caps" screwed into each "rocker box", one over each "Rocker adjuster pin".
. Later 72 650s have different "rocker boxes", both "Rocker adjuster pins" in a given box covered by one long oval "Inspection cover" secured to the box by four bolts.
As standard:-
. No T140 had the same "rocker boxes" with "Inspection caps" as a 71 T120R.
. Your bike's "rocker boxes" and "Inspection covers" are at least similar to those on later 72 650s - all 750 twins have the same single long oval "Inspection cover" secured to each rocker box, early by four bolts, later by six bolts.
If you clarify what you actually mean by "rocker cover bolts", you might get clearer replies?
If you mean "Inspection cap" gaskets - what Meriden termed "Joint washers" - these were made of fibre as "standard" for many years, these are still supplied by some dealers.
Better at helping to prevent "Inspection caps" loosening due to vibration are rubber O rings like these,
the thicker the better. I am not sure if Meriden eventually made O rings standard (part numbers were not always changed when circular fibre "Joint washers" were changed to O rings) but "Inspection cap" O rings have been available certainly in the UK for a long time.Difficult to tell from your photos if your bike has original type "Inspection caps" with two slots at 90 degrees to one another? If it does:-
. The caps should have serrated edges, your bike's rocker boxes are fitted with an E4609 "Locking spring" engaging with the serrations in each "Inspection cap"?
. Aftermarket "Inspection caps" are available with a large hex instead of the two slots. If nothing else stops your bike's "Inspection caps" loosening, you could fit these with a small hole drilled in the side of each hex, ziptie the caps to together?
Your bike has only one "head gasket", between the cylinder head and cylinder block.
Thank whichever deity you worship they did not. Utterly useless device invented by someone who either had never ridden a motorcycle or was only worried about the rear of the bike (including the tyre) and any pillion going rusty.
Thankfully Meriden had started to remove standard chain oilers even before the oif. 
Really good, solid information.All,
It would help understanding if the same components were referred to by the same names, ideally the ones Triumph used:-
. "Inlet rocker box" and "Exhaust rocker box"; each "rocker box" contains two rockers, a spindle on which the rockers rotate and several different washers on the spindle to space the rockers within the rocker box so the threaded "Rocker adjuster pin" is over the end of a valve.
. Each rocker box has two circular "Inspection caps" screwed into it, one over each Rocker adjuster pin.
It depends what your bike has:-
. Early 72 650s have the same as 71 650s - circular, originally slotted, "Inspection caps" screwed into each "rocker box", one over each "Rocker adjuster pin".
. Later 72 650s have different "rocker boxes", both "Rocker adjuster pins" in a given box covered by one long oval "Inspection cover" secured to the box by four bolts.
As standard:-
. No T140 had the same "rocker boxes" with "Inspection caps" as a 71 T120R.
. Your bike's "rocker boxes" and "Inspection covers" are at least similar to those on later 72 650s - all 750 twins have the same single long oval "Inspection cover" secured to each rocker box, early by four bolts, later by six bolts.
If you clarify what you actually mean by "rocker cover bolts", you might get clearer information?
If you mean "Inspection cap gaskets", Meriden made these fibre as "standard" for a long time and these are still supplied by some dealers.
Better at helping to prevent "Inspection caps" loosening due to vibration are rubber O rings like these,
Difficult to tell from your photos if your bike has original type "Inspection caps" with two slots at 90 degrees to one another? If it does:-
. The caps should have serrated edges, your bike's rocker boxes are fitted with an E4609 "Locking spring" engaging with the serrations in each "Inspection cap"?
. Aftermarket "Inspection caps" are available with a large hex instead of the two slots. If nothing else stops your bike's "Inspection caps" loosening, you could drill a small hole in each hex, ziptie the caps to together?
Your bike has only one "head gasket", between the cylinder head and cylinder block.
Thank whichever deity you worship they did not. Utterly useless device invented by someone who either had never ridden a motorcycle or was only worried about the rear of the bike (including the tyre) and any pillion going rusty.
As for the rocker boxes, my queries were intended to determine whether others with Unit 650s or similar engines experienced those fasteners loosening… and the answers were very helpful to me. So, thank you to everyone who responded.
As for oil consumption, I just checked my OIF tank—which is still full after the last 50-something-mile loop into Albuquerque. My practice is to check it before each ride—which takes just 30 seconds—and I’ll now start a note in my phone to annotate how much I add at [x] odometer reading.
I don’t really care what the answer turns out to be, as the plugs are not fouling, and the bike starts easily and runs great. I just need to know how much room to reserve for oil in my luggage on the over-the-road trips I plan to start taking this Spring—and for which I’d love some company, BTW. Vintage bikes are ideal but anyone is welcome, so long as they don’t mind my ~65 mph default cruising speed…
Finally, a new bit of fun. I’m headed down to the Pull-N-Pay tomorrow to harvest a couple of compact horns from a Volvo T5 C30 or S40 (mechanically almost identical), for $5 each (they’re ~$55 new). I fitted those horns to the red ’67 Midget ‘test mule’ for Creative Spridgets, and loved their bright, harmonious European sound and serious volume.
The OEM horn is loud enough standing still or in traffic, but I’ve found that a single, high frequency note gets lost in the wind at speed and doesn’t have enough midrange to carry sufficient volume down the road to check people entering the two-lane blacktop I use to get from the mountain down to the city.
If I can figure out a way to mount them so they're hidden and don’t ruin my bike’s aesthetics—and if the upgraded charging system can activate them reliably (probably will use a relay)—I will post a short clip so folks can hear them. I remember they were very effective in keeping people at the stop signs on the highway and in town, for that matter, in the Midget—which people often did not see coming.
As for oil consumption, I just checked my OIF tank—which is still full after the last 50-something-mile loop into Albuquerque. My practice is to check it before each ride—which takes just 30 seconds—and I’ll now start a note in my phone to annotate how much I add at [x] odometer reading.
I don’t really care what the answer turns out to be, as the plugs are not fouling, and the bike starts easily and runs great. I just need to know how much room to reserve for oil in my luggage on the over-the-road trips I plan to start taking this Spring—and for which I’d love some company, BTW. Vintage bikes are ideal but anyone is welcome, so long as they don’t mind my ~65 mph default cruising speed…
Finally, a new bit of fun. I’m headed down to the Pull-N-Pay tomorrow to harvest a couple of compact horns from a Volvo T5 C30 or S40 (mechanically almost identical), for $5 each (they’re ~$55 new). I fitted those horns to the red ’67 Midget ‘test mule’ for Creative Spridgets, and loved their bright, harmonious European sound and serious volume.
The OEM horn is loud enough standing still or in traffic, but I’ve found that a single, high frequency note gets lost in the wind at speed and doesn’t have enough midrange to carry sufficient volume down the road to check people entering the two-lane blacktop I use to get from the mountain down to the city.
If I can figure out a way to mount them so they're hidden and don’t ruin my bike’s aesthetics—and if the upgraded charging system can activate them reliably (probably will use a relay)—I will post a short clip so folks can hear them. I remember they were very effective in keeping people at the stop signs on the highway and in town, for that matter, in the Midget—which people often did not see coming.
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Lordmac
Well-Known Member
Is that front disc brake assembly a do-it-yourself kit or something you put together, and if so, where'd you get the components? Can we see some close-up shots of it?
And, about your baggage setup. Is that a one-piece deal? I've never seen anything quite like it (for lack of looking, I suppose) but I think it's what I could use for my bike. Who makes it, and what model is it?
On the tail luggage, yeah it’s pretty amazing if a little pricey. No: I have no affiliation with the manufacturer (I am not an influencer and don’t want to be one).
It’s a Saddlemen Tactical Seat Tunnel, and the best price I found w/free shipping (though you might find a better one elsewhere) was at Motomentum. I wanted something whose ’tunnel’ width would fit all three bikes—and it does: snuggles perfectly onto the OEM Triumph OIF saddle, more tightly onto the BMW R100RT/RS saddle, and even works with the steel rack on the ’51 FL’s rear fender.
I got it instead of traditional saddle bags because I have a side-by-side shotgun exhaust on the ’51 FL whose vintage Sporty mufflers would contact ordinary bags. But works well with the other, very different bikes.
It’s a soft-side bag that is very tough, cleans up well, and is water resistant. But it also has built-in rigidity, so does not sag, droop, or move around when attached—or while carrying it around, even loaded up. Comes with a rain cover that stows in a pocket I have facing the rear to afford a bit more room for my behind.
Quick-release straps with adjusting buckles that hold well—and will affix to just about any frame. Inside is cavernous and it has wider and narrower zippered pockets on the ends. It holds about two standard-sized grocery bags of food—and I put an ice pack in the main compartment for meat, dairy, etc., and >1/2 hour ride home, everything’s still cold.
I’ll do a separate post on the DIY front disc brake conversion when I get a moment…
