Restoring & Modifying 1971 OIF TR120

[Rudie]

think he said that he put a T160 kicker lever on it. Is it the (apparent) added length that makes this desirable, or is it that the pivot is at the bottom rather than the top?

Pivot at the bottom rather than the top, the lever tucks away better when not in use.

However, it is a mod that has been well known for many years ... new T160 levers were not available for a long time after all the NOS were taken, used were silly money. New ones are available again, but they are not cheap ...

 

[NM Bonny]

On the cover, I've decided to go with the OEM 1971 rivets (finally found a photo of the later model screws, thank you, Rudie). Here are before and after shots....

I also removed the steering lock to install a new one (didn't know one could order a new key - but it's okay, the lock was incredibly inexpensive), and knocked the dried out elastomeric bushes out, new ones on the way.

I'll bead blast and repaint the thing when at the machine shop this week or next, as the finish is pretty chipped up. I've got some leftover semi-gloss black ceramic engine paint left over from the cylinders on the '51 FL that should work fine...

 

[NM Bonny]

Took a bit to realize I had to reach in behind the R/H foot peg with a socket and breaker bar alongside the rear tire to loosen her up and get the kicker cover off--but once that was done, off she came without a complaint.

First two pics show how much work I've got ahead of me to get the kicker cover looking like the timing cover. Ugh...

Remaining show excellent condition of cam plate and shift pawls, kicker ratcheting mechanism, clutch release lever, and (though it's hard to see in the image) the tranny gears visible through the hole. There was only the slightest amount of very fine metal in the oil, so I'm thinking she'll work fine.

Questions:
- Looks like I've got to pull that kicker ratchet gear off the shaft--or perhaps just the kick-start lever--to R&R that shaft's seal...?
- What is the deal with the tightening mechanism on the kicker lever? The nut came off but the screw doesn't seem to want to come out.

Might as well R&R the kicker bush while I'm in there--but I'll inspect it.

The shift lever seal looks like I've got to dismantle the shift pawl mechanism with those four nuts to get in there. That bush may well get it, too--we'll see...

Naturally, the PO buggered up the drain plug badly, so that's gotta be replaced...

I'm replacing those cover Phillips screws with allen screws. I've never liked having to rely on a hand-driven impact driver on the road, though I've had one forever. Much nicer to throw a little allen wrench in your tool kit...

 

[NM Bonny]

Okay, never mind--I figured it out. You just back off the kicker retainer nut to protect the threads, then wack it with a brass hammer a few times, and out it comes.

Unfortunately, the kicker shaft and bush were trashed--as was the shifter bush. Thankfully, though, the shift actuator is in fine shape, just needs an O-ring (which I actually had in an assortment).

You can use a 16mm socket, which is the perfect size, to drive out the bushes. However, you must first tear up the kicker's oil seal to get a purchase from the inside with a drift to knock out the seat, and thus get access to the bush... not crazy about this bit of engineering. I suppose I could've used an expanding collet-type puller and slide hammer to remove that seat, but, gee whiz...

Anyway, a couple of bushes and a kicker shaft, and I'll be good to go. Well, after wearing out my fingers again on the sanding and polishing!

 

[NM Bonny]

While waiting for the parts to come in to finish the R/H side of the engine--and since my 'proof of concept' prototype caliper adapter is a success--I went ahead and ordered the Borrani rims and spoke kits for the DIY front disc conversion.... ouch.

Ah, well... nice bit about going with Buchanan's is they have prepackaged spoke kits that will fit this hybrid setup, so it was easy to match stuff up.

However, Buchanan's has evidently raised their wheel smith rates, as it's now $139 to lace and true a wheel. So, I'm definitely lacing and truing my own rims... Their polishing rates went up, too, so if I want to polish everything, I'll end up doing that myself as well. I might end up just polishing the outside edges of the rims, as I've seen that done and it looks cool... We'll see. I don't want to be liable for any collisions due to sunlight flashing off this bike and temporarily blinding some old codger....

 

[Rocky]

I'm getting a big kick out of following this thread. Great stuff
I rebuilt and trued the wheels on both of my vintage bikes. Having never done it before, it was tedious and tests your patience, but all wheels eventually came into line and were as good or better than from the factory. I was quite proud of myself
And yes, you don't want to blind some old codger with sun reflection

 

[NM Bonny]

I'm getting a big kick out of following this thread. Great stuff
I rebuilt and trued the wheels on both of my vintage bikes. Having never done it before, it was tedious and tests your patience, but all wheels eventually came into line and were as good or better than from the factory. I was quite proud of myself
And yes, you don't want to blind some old codger with sun reflection

That's nice to hear. My hope is to add some graphic detail to the manual for people who, like me, are new to these machines, and to enjoy a virtual hangout with people I unfortunately may never meet.

Thanks for the reassurance on wheel-building. This will be my first foray beyond truing and balancing, so it's a little bit of a gamble. But I find wrenching on a vintage machine calming and even meditative, if that's not overstating the case--and I surely need both things of late. So, there's a benefit beyond building the wheel itself, whatever that outcome.

Looks like some stuff arrived, so I'm headed out to rebuild the oil pump and perhaps re-install the timing cover...

 

[speedrattle]

an easy way to do wheels is to insert the spokes in place in the hub setting on top of the rim as a guide. then tape them together where they cross. once all the spokes are arranged in tbe correct crossing patterns just push em into the holes in the rim and screw on the nipples.

 

[NM Bonny]

an easy way to do wheels is to insert the spokes in place in the hub setting on top of the rim as a guide. then tape them together where they cross. once all the spokes are arranged in tbe correct crossing patterns just push em into the holes in the rim and screw on the nipples.

Ah... probably a lot quicker than doing them one at a time and getting confused mid-route, too. Thanks.

I see that the Harley pattern and the Triumph conical pattern differ. Harley crosses over 4 spokes each time, whereas a Triumph conical crosses 2 each time. That said, each method creates similarly-shaped triangles--and both are 40-hole rims. So, the bike should end up looking balanced and aesthetically pleasing.

Also: talked to the machinist today, and he's hoping to get some time in early March to make up the working prototype caliper adapter. He agrees that my design is easily strong enough to handle the shear force exerted on it via the studs and screws.

Also, he said it looks like a simple, two-setup part that will require a straightforward fixture to machine the outside profile to 'nest' the caliper into the adapter. Of course, it'll require small radii at the 'step' to avoid cracking, so the nesting feature will be more aesthetic than functional--but he said no way the 3/8" allen screws are going to shear from the kind of force exerted on them. We concur that the Wilwood caliper would fail before my part or the screws.

 

[NM Bonny]

More glacial progress...

Rebuilt and tested the oil pump and check valves (simple procedure is in manual), installed with new cone nuts and washers, new seals into cover, a dab of assembly lube on shafts that insert into seals, some ultra gray here and there, and on she went. Don't mind the smudgy cover from my fingers...

 

[NM Bonny]

Buchanan's called. The Harleys have a tapered spoke that's a little heavier at the rim end, but significantly heavier at the hub end than the Triumph OEM spoke for conical hubs. So, we're doing two things to balance out the aesthetic, while still remaining well within safe boundaries.

First, they can punch the Borrani rims to take nipples the same size on both front and rear.

Second, the Harley spokes are much thicker than the Triumph-spec conical hub spokes. I didn't notice that the former taper, whereas the latter are the same thickness.

So, it turns out they can put together 7 gauge spokes (rather than OEM 9 gauge) for the rear conical hub, and then provide a tapered 7 to 9 gauge set for the front. That should produce a cleaner, light-looking aesthetic that matches up better--rather than just slapping OEM Harley spokes on the front wheel (they'd be very clunky if put on the rear, and I'd have to drill out the hub to accept them). The difference between 7 and 9 gauge is very small: .1875" vs .1563".

 

[Lordmac]

I will eventually mount to this bike, to receive a Bridgestone Battlax BT46 100/90-19 up front.

This tire ok'd for tube-type wheels? Some of those fancy-er Bridgestones are only for tubeless, I heard. Looks like a nice tar, though I got those TT100 K81s on mine.

 

[NM Bonny]

This tire ok'd for tube-type wheels? Some of those fancy-er Bridgestones are only for tubeless, I heard. Looks like a nice tar, though I got those TT100 K81s on mine.

Whew, you scared me for a minute... Here's what Bridgestone's website says:

"Only for the tires stamped “USE TUBE ON TUBE TYPE RIM” on the sidewall, an appropriate tube can be inserted to allow use on tube type rims." (see 1st pic)

Buchanan's invoice notes warn that you just use protection against tube puncture by the nipples, so that implies that I'm good to go. I'll be using a rim strip.

Here are the specs on the rims and spokes, should anyone try this conversion. (2nd and 3rd pics). Spoke tension with this setup is:
Fr: 50-60 inch lbs. max
Rr: 50-60 inch lbs. max

Yes, I think the bike will handle excellently with these tires, the Hagon rear shocks I got, and the special 'low stiction' O-ring replacements for the front dampers that Rudy pointed me to (earlier post).

 

[NM Bonny]

Rims and spoke kits en route from Buchanan's, and Draganfly finally shipped the upgraded condos for the 750cc conversion down the road (they were back-ordered). I'll post some pics when they get here, before oiling them up extra good for storage. The kicker cover bushes are in the same shipment, so if I can get taxes done and move ahead with the sanding and polishing, I should have the R/H side of the engine buttoned up fairly shortly...

 

[NM Bonny]

They arrived, and look lovely as-is. Dunno if I'll polish them further or not, as they look fabulous. Although it looks like they'd come up brilliantly on the buffer wheel without much ado...

It's hard to see in the packaging, but the nifty tapered front (Harley hub) spokes match the Bonny-hub single-diameter spokes very nicely. As mentioned earlier, the nipples are all the same size. This should look really nice when laced up.

Last photo shows width of front tire at widest point unmounted--but note that this tire's beads will get squeezed together slightly to fit the 2.15 rim. At the rear, the unmounted tire's beads sit almost exactly at the width they'll reside on the rim.

I'm excited to get the caliper adapter machined and lace these up!

 

[NM Bonny]

Update: I've been patiently waiting for time with the machinist and as luck would have it, he called today. Looks like we'll be working on the prototype caliper adapter next week, if the anticipated break in his National Labs work materializes.

The part will require custom soft jaws to hold it securely in the big CNC mill--but the upside is that if anyone wanted to do this conversion, it'll be easy replicate the adapter extremely accurately. It requires 1"x3" 6061-T6 bar stock, but I can get 2 parts per foot of material, so not terribly expensive from a materials standpoint.

So: I hope to be R&Ring the sealed bearings in the Harley hub (maybe a quick polish), lacing up the front wheel, and getting her off the jack soon. Will post photos at that point--and then it'll be on to refinishing and re-bushing the top triple clamp, futzing with the fender (hope it fits as-is), fitting the bars, master cylinder, and brake hose.

 

[Rudie]

futzing with the fender (hope it fits as-is)

Advance apologies if this has been mentioned already - the standard 71 fender is useless for keeping the sliders parallel. Original fenders had only two thick wires on each side to the slider; after BSA or Triumph was sued successfully when all four broke, the fender went under a front wheel and the bike crashed, BSA/Triumph added a third (short, straight) wire on each side between the fender and the slider mount.

However, single disc, because there are no bushes between sliders and stanchions, the forks twist when the brake is applied, especially applied hard - my T160 suffered this despite the better brace NVT fitted as standard. Your modified bike on the road, ime you will find you need a decent brace between the sliders.

 

[NM Bonny]

Advance apologies if this has been mentioned already - the standard 71 fender is useless for keeping the sliders parallel. Original fenders had only two thick wires on each side to the slider; after BSA or Triumph was sued successfully when all four broke, the fender went under a front wheel and the bike crashed, BSA/Triumph added a third (short, straight) wire on each side between the fender and the slider mount.

However, single disc, because there are no bushes between sliders and stanchions, the forks twist when the brake is applied, especially applied hard - my T160 suffered this despite the better brace NVT fitted as standard. Your modified bike on the road, ime you will find you need a decent brace between the sliders.

Yes, I believe you did mention this and recommend a nice-looking brace to reinforce the forks. Thank you very much.

 

[Rocky]

Enjoying the progress and updates

 

[NM Bonny]

Hey, I've got another question about the 750cc upgrade, which will happen whenever the existing barrels wear out (if not sooner).

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? Also, at what point did Triumph begin putting 9-bolt heads on 650s?