I lent the sidecar to my friend "Howard "Shotgun" Winchester, famous former Big D Cycles dirt track racer, so that he could continue to ride into his 90s. He could no longer hold the bike up in a pinch situation. Sold the Goose.
Introduce yourself and your classic bike(s) - with photos!
- Thread starter grandpaul
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Very good!
1992 Yamaha TDM850 "bug eyes" adventure bike, currently cleaning the carbs, fuel tank, etc. It sat too long when we moved.
2000 Triumph Legend 900 triple, used to be Sally's bike but she bought herself a 2014 Kawasaki Vulcan 900 V-twin. I installed and paint-matched this Shoei quarter fairing for highway and cold/wet weather riding
and last, but will never be mistaken for least, my salvage built 01/03 Kawasaki ZRX1200R, my 3rd ZRX salvage build. This is my regular rider and is currently being "refreshed" after never having been washed in 10 years. Total maintenance, new chain, etc.
"That's all, folks"
2000 Triumph Legend 900 triple, used to be Sally's bike but she bought herself a 2014 Kawasaki Vulcan 900 V-twin. I installed and paint-matched this Shoei quarter fairing for highway and cold/wet weather riding
and last, but will never be mistaken for least, my salvage built 01/03 Kawasaki ZRX1200R, my 3rd ZRX salvage build. This is my regular rider and is currently being "refreshed" after never having been washed in 10 years. Total maintenance, new chain, etc.
"That's all, folks"
Great bikes 
Some of you know me, others do not. I live outside of Albuquerque and my be seen tooling around on my modified ’71 Bonneville T120R.
Nearly finished after almost two years of on-and-off work, it’ll soon get the finishing touches done: polish, paint, and decals on the side covers; progressive springs in the forks (front 11.5’ disc is a lot more powerful than stock); and an aluminum replacement for the steel rear brake plate stop strut. That will just about do it!
Hit the post office today, and a guy and his wife were waiting outside with questions—well, he had questions, that is...
“Where can I get one? How much do they cost? Wait, is that a kick starter?”
When I told him how little I had in it, he just about yanked his wife’s arm off while they headed for the car. I feel that I’m a bad influence...
Nearly finished after almost two years of on-and-off work, it’ll soon get the finishing touches done: polish, paint, and decals on the side covers; progressive springs in the forks (front 11.5’ disc is a lot more powerful than stock); and an aluminum replacement for the steel rear brake plate stop strut. That will just about do it!
Hit the post office today, and a guy and his wife were waiting outside with questions—well, he had questions, that is...
“Where can I get one? How much do they cost? Wait, is that a kick starter?”
When I told him how little I had in it, he just about yanked his wife’s arm off while they headed for the car. I feel that I’m a bad influence...
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It is a beautiful bike man!
Of course you are ...According to the o.h., I am also bad influence, because my daughter wants to learn to ride a motorcycle ...
Lordmac
Well-Known Member
Absolutely. Girls and motorcycles do mix.
Lordmac
Well-Known Member
I've been meaning to ask you another question about the "big" front disc on your T120 Triumph.
Alrighty, then . . . we might all agree that Triumph engineers (along with AP, Lockheed et al) designed the disc brake system for seventies/eighties Triumphs, which many say is an "okay" braking system but maybe not the greatest out there. However, the design PROBABLY takes into consideration the torque and force factor on only the left side fork (assembly), thusly deciding on a disc diameter of ten inches or so and a caliper with "X" amount of "squeeze" power so as not to cause a problem with said left fork. You have a larger-than-normal diameter disc coupled with a different caliper which might have more robust stopping power thereby exerting forces on the left fork leg greater than which was originally intended. Have you any concern as to that possibility? I was just wondering how one arrives at a comfortable conclusion to such "custom" additions . . . unless they have an engine in their ear.
Interesting question.
I guess that it doesn’t concern me very much for two reasons. First, because the fork tubes are hardened steel and very stiff. Second, the wheel is going to lock up—and the tire will lose traction—long before that hard steel tube is going to flex significantly, let alone fail.
That said, Rudie early on in my ‘Modifying a 1971 OIF’ thread suggested a fork brace to reduce flex through the triple clamps—which can indeed affect fine steering input if one is leaned over and braking in a curve. I think if I were regularly pushing the bike hard through twisty backroads, throwing it from side to side, diving deeply into sharp corners and braking forcefully over and over, that would be a worthwhile investment.
But I’d characterize my riding these days as ‘spirited,’ by which I mean I’m nowhere near the frame’s limits.
However, I will be installing progressive-rate springs in the forks in the next few days, and am getting more comfortable with the setup each time I ride the bike. And as you point out, I do have a high-performance brake and, of course, I have fitted modern tires—which means the bike is effectively a rolling workshop to feel out the weak links. I may indeed find that Rudie’s suggestion is well worth the investment.
So, it could well be that after eliminating the squishy spring factor and as I become even more comfortable pushing the bike harder through the S-curve coming up from the river to my place (whose entry you see in my avatar photo), I will be able to discern more subtle variables like you’re talking about. I will report data from this ongoing experiment in my ‘Modifying a 1971 OIF’ thread.
"designed" ...
I cannot say I know all the details because, by the time I had discovered what I do know, those who could have filled in the gaps were not contactable (not all dead, many just retired). Afaik:-
. First Triumphs and BSAs fitted with disc brakes were the 1970 Daytona 200/Formula 750 triple racers, a single disc on the rear (10" Fontana 4LS drum on the front); caliper was one (offside?) of the pair supplied for the front wheels of British Austin Mini 1275GT and Cooper S cars, the caliper fitted a 10" disc:-
... subsequently, some racers had the front Fontana drum replaced with two of the calipers and discs; ime, this is how you will see most original racers and all copies.
. In 1972, when Triumph wanted a front disc for first the 750 twins and then the T150, the alloy caliper must have been too expensive, as Lockheed supplied a slightly modified version of the offside steel caliper supplied to Cooper for his version of pre-1275 Mini Coopers.
again ... the AP Lockheed parts supplied never took anything "into consideration". At the same time as Meriden were planning to fit the front disc, they were having to hastily redesign the front mudguard/fender mounting, because BSA/Triumph had been sued successfully in the US by a rider whose conical hub fender had broken away from all four "wire" stays, stuck between front wheel and road, tipped him off. That is why 73 and 74 disc brake fenders have that horrible lash up of stays modified from the pre-conical forks fender mounting; the stays worked fine with a drum brake between them, not so fine with one caliper and disc on one side of the forks.NVT developed a different front fender mounting for the T160, also fitted to 76 and later twins, that does at least keep both sliders moving up and down together. However, grab certainly a T160 single caliper/disc hard and the forks still twist;
however a T160 is 500 lb. dry ...The stanchions are not what flexes, it is the joint between slider and stanchion, any and only rigidity there is the much smaller diameter damper rod, compromised by the flexible seal between damper head and stanchion.
I will respectfully disagree with that.
First, the fit between the slider and fork tube is surprisingly close, as I found out when I had to hone my later model sliders a few thousandths to slide freely on my ’71 fork tubes (probably just a little corrosion in the aluminum bores). The hardened steel tube when inserted into the aluminum slider effectively becomes an assembly whose rigidity is enormous, even as measured without the damper rod in place.
Second, as for the tube by itself—that is, the run of ‘unreinforced' tube extending from the slider up to the triple clamps—you can look up the deflection specs for hardened chrome steel tube of this diameter and wall thickness: it does indeed flex [x] amount over [y] span, like anything else. However, the degree of flex as I’ve said is going to be fairly small for the several inches of unreinforced tube.
But will I notice the flex? Probably not very often because I don’t run this bike on a track and am probably not skilled enough to test its limits even if I did: I’m merely dodging wild horses and F150s on the two-lane blacktop. But the symptom upon forcefully applying the brake would be a sudden, if small increase in understeer leaned over in a right-hander or oversteer in a left-hander (don’t forget to factor in negative steering: this sounds backward but I don’t think it is), due to the caliper shoving the slider into the lefthand fork tube and flexing it a tad… which, in turn, skews the axle’s long axis vis-a-vis the handlebar (whose planes are supposed to be parallel). A fork brace is supposed to reduce that divergence, if I understand its function.
That said, even now I can feel a definite difference between the far heavier ’84 R100RS's squishy frame (it has a CNC aluminum fork brace fitted) and the ’71 Bonny’s all-welded, far stiffer OIF ‘backbone’ design accelerating up through the S-curve over uneven pavement on HWY 165. The lighter weight (100+ lb.) and the OIF stiffness produce a more confidence-inspiring ride (the bikes have identical tires fitted and their bars are about the same width).
But like I said, the progressive-rate springs get here mañana, so if they yield a noticeably firmer front end, I’ll feed her a bit more throttle next time the sun comes out, and we’ll see what’s what. The results will be reported—good, bad, or ugly—on the main ‘mods and resto’ thread for the ’71 Bonny.
Lordmac
Well-Known Member
From my experience with progressive springs, they are a wee bit softer and more forgiving (on the small bumps) than stock springs, yet still firm enough to make it seem like "normal" springs when yer digging in.
I have seen it, that is why I know it happens - T160, it is possible to see it just grabbing the front brake lever hard while hanging off the left side of the bike. That said, I appreciate it might be move obvious on a T160 than an o.i.f. because of the weight difference.
Even after the "Ceriani lookalike" forks were introduced for 71:-
. The F750 triples continued to use the earlier steel slider fork; as standard, each leg has a fixed bush at the top of the slider, a moving bush within the slider between slider and stanchion.
. The famous production racing triple "Slippery Sam" continued to used the steel slider fork and Fontana drum brake even after Triumph began fitting the disc brake to road bikes, Les Williams and the riders only accepting the later forks and their rigidity compromise when it was realised the bike could have twin front discs (by fitting a left hand slider on the right leg with the caliper mounting at the front of the slider) and still stay within the production racing regulations.
I appreciate that ...
Not compared to the visible flex between stanchion and slider.
Lordmac
Well-Known Member
Single front disc certainly on the T160 does both.
Original fork seal type, ime not unusual for the disc side to need replacement every few thousand miles (I reached the point of changing my bike's at the 3000 mile service 
).I fitted Leak Proof seals at the same time as I fitted twin front calipers; the sliders then only move straight backwards under braking; the Leak Proof seals have done "What it says on the tin"
but I cannot say how long they would with just a single caliper.
