Restoring & Modifying 1971 OIF TR120

[sikatri]

The detailing is fabulous! I love the way the dash looks with the dials popping out of the plain instead of fully recessed. Very elegant solution and the headlight detail is just outstanding. Very refined detail, a bit of old and a bit of new. Excellent!

 

[NM Bonny]

The detailing is fabulous! I love the way the dash looks with the dials popping out of the plain instead of fully recessed. Very elegant solution and the headlight detail is just outstanding. Very refined detail, a bit of old and a bit of new. Excellent!

Very, very nice of you to say. I agree, of course, but as there's no accounting for taste, it's nice to hear others appreciate the unique, bespoke stuff I'm doing to this period-evocative OIF cafe bike.

Other news:

Got the rear tire dismounted to check the hub offsets (1.05" non-drive side; 1.91" drive side; OEM rim outside width 2.97"), removed the old spokes, and after lunch will knock out the bearings... (original balls in open cages)... and begin the laborious sanding and polishing of the conical hub.

I'll have to find some method of recording which way the spokes went, as the grooves in the aluminum from the old spokes will disappear with my finishing work...

The brake linings look essentially new, just a few thousandths thinner than the new pair I've got (first photo)--so back in they go.

To my delight, the custom spokes Buchanan's sold me (tapered to visually come closer to matching the front end's tapered spokes) will fit without enlarging the holes in the rear hub. There are different bends for inner and outers on the drive/brake side.

Finally: the unused Dunlop K70 tires in stock sizes are available to whoever wants them for the cost of shipping, plus a gourmet cheeseburger ($15 each) for my trouble in dismounting them. Yuck...

Any takers...? When I say 'unused' I mean they've been mounted but the bike was never ridden, so they still have the little tits from the mold on them.

 

[NM Bonny]

The neighbor was nice enough to turn me a wheel bearing drift on the 'old' lathe (he uses the CNC lathe most often these days), based on the drawing and specs at the end of the repair manual.

Works great. You just knock the spacer and one bearing out, tap the spacer out of the first bearing, then use it and the drift to knock out the second bearing. Takes, like, 90 seconds to do the whole job.

I thought there was a grease seal on the brake drum side, but no: it's a threaded bearing locking ring. Regardless, the old OEM open cage-style bearings were pretty rough on one side especially, so looking forward to the new sealed units.

I'm knocking off as I'm beat, but the hub is now ready for sanding, polishing, and fitting new bearings so I can lace up the Borrani aluminum rear wheel. Very excited to get the swing arm bushes R&R'd, so I can put this machine down onto its new tires for the last time...

 

[NM Bonny]

Okay, here is the penultimate install--essentially final but for the up/down adjustment knob, which will be done next weekend. I could use it 'as is' with the usual, manual adjustment method, but think the up/down knob feature will be really neat...

I believe that I've netted much-improved visibility to oncoming traffic and drivers who might otherwise pull out in front of me from side roads and at intersections. But vastly improved night vision for me. The warning lights' brightness level seems just fine. Also, it looks pretty good.

I think the headlight mod is a success!

 

[sikatri]

Fabulous!

 

[CarlS]

Okay, here is the penultimate install--essentially final but for the up/down adjustment knob, which will be done next weekend. I could use it 'as is' with the usual, manual adjustment method, but think the up/down knob feature will be really neat...

I believe that I've netted much-improved visibility to oncoming traffic and drivers who might otherwise pull out in front of me from side roads and at intersections. But vastly improved night vision for me. The warning lights' brightness level seems just fine. Also, it looks pretty good.

I think the headlight mod is a success!

This looks absolutely great. Beautiful work.

 

[grandpaul]

Finally: the unused Dunlop K70 tires in stock sizes are available to whoever wants them for the cost of shipping, plus a gourmet cheeseburger ($15 each) for my trouble in dismounting them. Yuck...

Any takers...? When I say 'unused' I mean they've been mounted but the bike was never ridden, so they still have the little tits from the mold on them.

I'll take those!

PM sent.

Thanx, and keep up the great work...

 

[NM Bonny]

Morgo notified me that they finally got in a half dozen of their 750cc big bore kits... so I bought one.

I'm hopeful that this original power plant will run for some time, but now I'll have the top end of a new, even more powerful engine on the shelf for whenever this one wears out.

When it arrives, I'll inspect the parts and take a few photos before oiling the bores and storing the kit.

 

[NM Bonny]

So, I caught a break (finally) in the refurbishment of this bike: the swing arm had virtually no side-to-side play or 'shake', it moves freely, and when I greased it up, the dust excluders did not crack. So, I pulled the decals from the Hagon shocks and called it good enough. On to building the rear wheel!

Note: for anyone who does the DIY rear-set conversion outlined earlier in this thread, the bolts on the high-quality aftermarket folding pegs I bought on Scamazon are too long, and make accessing the swing-arm's zerk fittings difficult. So, I cut them and cleaned up the threads (1st pic - need to remove the unnecessary lock washer, as the bolt is barely into the nylock portion of the nut).

Finally: I was thinking of getting another round English mirror like Sikatri used, which I think is the same as I have on my '51 Harley FL. However, the slash-cut pucks won't fit the 7/8" bar's thicker-walled aluminum tubing.

And I actually like the inexpensive, Japanese tapered parallelogram mirrors the PO put on the bike because they roughly match the style of the same period Ducati 900 whose fairing inspired the one I've installed. Plus, they're not convex, which I really like: gotta see those cops before they get close enough to clock my speed...

So, I hit one of the aluminum mirror cases with the buffer wheel... and it looks pretty good (2nd pic). Unfortunately, per the 3rd pic, the clunky mechanism won't fit the I.D. of the thick-walled 6061-T6 aluminum clip-on bars. So, I'm buying a leftover chunk of 5/8" 6061-T6 bar from my neighborhood machinist, and will drill, tap, and slash-cut some pucks to grab the bar's I.D. per the mechanism of mirror on my '51 FL.

Yet another small fabrication task, but I'll retain the period look I'm going for and also save some more dough...

 

[NM Bonny]

Another option would be to fit some 1984-86 Kawasaki Ninja mirrors to the fairing...

 

[sikatri]

The bar end look nice.

 

[NM Bonny]

The bar end look nice.

Yes, I agree--thanks for weighing in. I center-drilled the aluminum bar yesterday, so hope to get the pucks finished this weekend.

 

[NM Bonny]

...and here they are. The 5/8" rod was just a few thousandths too fat, so I put it in the drill press and held a file against it, then held an old sanding belt around it to smooth it out. The hardest part was the no. 7 central hole, which I finally gave up on and used a lathe. Done in 60 seconds.

**Note: be careful when holding a file w/o a handle against a turning part. My machinist's father once drove a file straight through his hand that way...

After tapping the inboard puck and cutting it off @ 60 degrees, you just enlarge the remaining 2/3 to 1/4", followed by the central moving puck--created by another 60-degree cut--to 5/16".

The last photo of the pucks shows how the mechanism is intended to work, if my explanation wasn't clear: the center puck gets shoved off its axis when I tighten the screw--the perpendicular movement enabled by the larger hole--and it grabs the opposite side of the bar's I.D. from the other two pucks. (Important to break the edges of the center 'active' puck, so it doesn't gouge the inside of the aluminum bar.)

The screw may arrive mañana, so I'm eager to see if the theory plays out in the real world. I think that the only issue may be that I didn't want to mess with broaching a keyway into the puck that contacts the mirror. So, I just sawed off the keyed portion of the mirror and if it vibrates down around the screw's axis, I'll drill the outboard puck and the mirror for a teensy pin.

In other news, I was pleased to find that the OEM '71 speedo drive works fine. I just had to put something like 40 strokes of the grease gun through it to get all the grit out (?!), alternating with putting it on the drive ring threaded into the hub to rotate it. Eventually, it got to where I could easily turn it with a finger (though it still feels like it may take 3 or 4 mph off my top end...)

I couldn't believe that the 53-year-old zerk fitting, which lacks a barb, worked. But it does: you just gotta hold the grease gun's nozzle on firmly, and virtually no grease squirts out. Amazing...

 

[NM Bonny]

So, a bit more progress--and the fairing is finally done! I'm grateful to Sikatri for sharing his experience on fitting an Omega fairing, as his experience made me less fretful about taking the plunge.

First few pics show the aluminum headlight vertical adjustment mechanism... which to my amazement actually works. It was a lot of work but it's very neat to be able to dial in your up/down headlight adjustment from the saddle if you've added a passenger or significant camping load. The 5/16-18 threads provide a very accurate adjustment (I almost used 24-pitch but that turned out to be unnecessary).

All I have to do if I want more downward adjustment is thread the rod a bit more on the end toward the clevis--and maybe add a longer spring, though this seems to hold the adjustment well.

The remaining pics show that the mirror attachment method discussed in the previous post works great: the pucks hold the mirror very tightly, and without having to gorilla the stainless allen screw or resort to a referencing pin. Total success, and I made up two pieces of 2" long stock for the expansion pucks. So, if I decide on twin mirrors, a quick morning's work and I'll have the R/H mirror polished and fitted, too.

Picked up some 1/4" x 1" 6061 flat aluminum bar from Lowe's to make a lighter replacement for the mild steel drum-affixing strut. It'll have some holes drilled in it to further lighten it, plus it'll look nice with the aluminum rear rim and chrome chain guard.

 

[sikatri]

You’re welcome. That’s just awesome and a great piece of engineering! Love the detail!

 

[CarlS]

So, a bit more progress--and the fairing is finally done! I'm grateful to Sikatri for sharing his experience on fitting an Omega fairing, as his experience made me less fretful about taking the plunge.

First few pics show the aluminum headlight vertical adjustment mechanism... which to my amazement actually works. It was a lot of work but it's very neat to be able to dial in your up/down headlight adjustment from the saddle if you've added a passenger or significant camping load. The 5/16-18 threads provide a very accurate adjustment (I almost used 24-pitch but that turned out to be unnecessary).

All I have to do if I want more downward adjustment is thread the rod a bit more on the end toward the clevis--and maybe add a longer spring, though this seems to hold the adjustment well.

The remaining pics show that the mirror attachment method discussed in the previous post works great: the pucks hold the mirror very tightly, and without having to gorilla the stainless allen screw or resort to a referencing pin. Total success, and I made up two pieces of 2" long stock for the expansion pucks. So, if I decide on twin mirrors, a quick morning's work and I'll have the R/H mirror polished and fitted, too.

Picked up some 1/4" x 1" 6061 flat aluminum bar from Lowe's to make a lighter replacement for the mild steel drum-affixing strut. It'll have some holes drilled in it to further lighten it, plus it'll look nice with the aluminum rear rim and chrome chain guard.

Your work is astounding!

 

[NM Bonny]

Made some muffler mounts from 1/8" 6061 aluminum. I've included the measurements in case anyone wants to add these Dunstall replicas without having to figure out the design for the mounts.

I did not include the degree of the bend because: (1) I assume people standing on the passenger foot peg tabs will have bent them slightly over time; and (2) they appear to be slightly different side to side.

Looks like about 1/4" spacers needed on the R/H side; I'll see what's what on the L/H side later on. I'll get some aluminum spacers; just used a nut for mock-up...

Finally: the kick-up of the mufflers, in order to match the angle suggested by the pipes (in my case, unbalanced but this shouldn't matter), looks a touch low in the final photo. That's because the muffler pivots slightly on the fulcrum of the mount's large forward bolt a little bit--until you tighten the muffler clamp.

So, the sequence would be:
(i) install the 5/16" x 1" bolts and spacers into the muffler, and tighten the bolts finger tight--gently;
(ii) slide the muffler w/clamp onto the pipe and check rotational alignment at mount where it parallels muffler bolt channel;
(iii) bolt the mount to the foot peg tab just tightly enough to create a steady fulcrum;
(iv) gently lift muffler to precisely align with pipe kick-up and check rotational alignment, then tighten the muffler clamp;
(v) securely tighten the 5/16" x 1" bolts;
(vi) securely tighten the large foot peg bolt.

The crankcase ventilation pipe isn't attached to the aft 5/16" bolt in this photo; it will be behind the muffler and not visible from the side.

HTH...

P.S. - these will get sanded and polished whenever I get to the side covers and (soon to be fabricated) brake drum backing plate strut. I am getting antsy to get this bike on the road before winter sets in!

The rear hub will get polished next, though, because I can't very well do that after I build the rear wheel...

 

[NM Bonny]

Okay, this task is finished!

I'd forgotten that I had straightened the L/H passenger foot peg mount, because it now affixes (as well) the DIY rear-set mount. So, as you can see, no spacers needed on that side (I had a 1/2" thick 5/16" aluminum spacer, so just sawed it in half).

Also: after fiddling with that elaborate jig, I realized all that I had to do was lay a straight edge across the swing arm at [x] inches from the aft end... and voila. I got a reference point in 3D space to align the mufflers vis-a-vis each other. They're within 1/4" in every dimension now, so I'm satisfied.

You have to use the largest sleeves that come with the mufflers, which is a little fiddly. Best method for me was to insert them ~1/2 into the mufflers, then slide the sleeve onto the exhaust pipes, push the muffler to where you want it, and finally use a long drift to gently tap the sleeve back into the muffler inlet and rotate the muffler to get the mount aligned in that plane.

The last few shots show that the crankcase breather pipe is nicely hidden behind the R/H muffler; it attaches to the mount, as it did with the OEM cans.

I'm glad I chose this muffler design, even though they're a bit heavier than OEM. They breathe better by all accounts, and when rewrapped won't be too loud. (That may happen whenever I get around to polishing the muffler mounts, as I want to get this machine on the road this year.)

 

[CarlS]

Okay, this task is finished!

I'd forgotten that I had straightened the L/H passenger foot peg mount, because it now affixes (as well) the DIY rear-set mount. So, as you can see, no spacers needed on that side (I had a 1/2" thick 5/16" aluminum spacer, so just sawed it in half).

Also: after fiddling with that elaborate jig, I realized all that I had to do was lay a straight edge across the swing arm at [x] inches from the aft end... and voila. I got a reference point in 3D space to align the mufflers vis-a-vis each other. They're within 1/4" in every dimension now, so I'm satisfied.

You have to use the largest sleeves that come with the mufflers, which is a little fiddly. Best method for me was to insert them ~1/2 into the mufflers, then slide the sleeve onto the exhaust pipes, push the muffler to where you want it, and finally use a long drift to gently tap the sleeve back into the muffler inlet and rotate the muffler to get the mount aligned in that plane.

The last few shots show that the crankcase breather pipe is nicely hidden behind the R/H muffler; it attaches to the mount, as it did with the OEM cans.

I'm glad I chose this muffler design, even though they're a bit heavier than OEM. They breathe better by all accounts, and when rewrapped won't be too loud. (That may happen whenever I get around to polishing the muffler mounts, as I want to get this machine on the road this year.)

Outstanding work!!

 

[NM Bonny]

Thank you, Sir!

I'm fixin' to begin sanding and polishing the rear hub in preparation to lace up the Borrani rim. People may recall that the DIY front disc conversion resulted in a net unsprung weight reduction of 4 lbs., while gaining a vastly improved front brake.

In the rear, the only change is the rim itself, which to my surprise as you can see is just 6.8 ounces lighter. Of course, it's a wider rim than the OEM steel version, so the comparison isn't entirely accurate. I would think the difference would be closer to 3/4 of a pound, at least.

Anyway, next post--which may be a while--will be what I hope is my first successful build of a rear conical hub... and the bike finally on its new rubber.

P.S. - This OEM steel rear wheel is for sale for $20 plus shipping. The chrome is far from perfect but it looked very true when mounted--and I cut the spokes carefully, so there was no stress on it during the process of removing the hub.