Bringing My '79 Bonneville Special Back to Life

L.A.B. said:

Al,

Hopefully, you have removed all 8 screws and 2 nuts? Don't mistake the oil drain screw for one of the eight. The gear pedal also has to be removed first.

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Right again, L.A.B. There it was, just forward of the drain screw, hiding under a bulge in the bottom of the cover. I was able to hook fingernails under the bottom while tapping with the plastic mallet and it slowly came off. Thank you!!!

Tulsaalva said:

The thing does take an athlete to squeeze the lever.

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It shouldn't do?

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Alright... I'll start squeezing tennis balls. Come to think of it, Sixteen can squeeze tennis balls (and Triumph clutches) and I'll go back to my BMW, which he rode away on a few minutes ago. It's his six month "mensiversary" with his girlfriend and they're going out to dinner. Young love...


Al

Barnett plates are replaced in Triumphs one-for-one.

If you have the correct clutch springs, and adjust everything properly, the clutch pull should be "normal", which is to say, not very hard.

grandpaul said:

Barnett plates are replaced in Triumphs one-for-one.

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Okay. I've not gotten the plates out yet. It seems I need a special tool, a screwdriver with a slot in the center of the blade to allow for the bolt. I'll make one but I want to go to the hardware store and buy a screwdriver with a wider blade. It will then go into the Triumph tool kit along with the American allen sockets I've bought.

If you have the correct clutch springs, and adjust everything properly, the clutch pull should be "normal", which is to say, not very hard.

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I'm sure the clutch springs are the original ones. They have about 14,000 kilometers on them. Since they haven't been compressed for twenty-five years, I'm hoping they won't need replacement. Is there a way to test them?

I did find a bit of a "kink" in the routing of the clutch cable and routed it into a more gentle curve. I'm hoping that lightens up the clutch a bit.

Before we began the disassembly, the clutch on the Bonneville was much harder than on the R80RT. I don't know if that tells you anything.

Thanks, y'all! I have to say again that this project would have stalled long ago without your help. Sixteen has enrolled in a course in Tulsa Tech on motorcycle mechanics during his junior and senior years. It's not that he wants to be a m/c mechanic his whole life but that he wants to earn more than minimum wage at a part-time job while in college. He also wants to be more qualified to work on his own bikes. I can't say I blame him!

Anyway, he's going to be riding the Special to Tulsa Tech this fall semester. I daresay he'll be the envy of the other students, riding a virtual museum piece to school.

By the way, I've decided to sell the Long Range and will begin to get it ready for that after the Triumph is on the road. The instructor at Tulsa Tech will be looking for project bikes to use in classroom instruction and may be interested in the Commando, depending on his other offers. The class is aimed at producing Harley mechanics, so they may not want the Norton. We'll see.

Al;

The clutch is out, cleaned and dried. The plates look to be in very good shape so I'll be able to reuse them.

After a bit of experimentation, I learned that the easiest and gentlest way to separate them was to insert a small slot blade screwdriver into the "valley" between the friction material. I had to take them out one at a time in order to work them past the shift lever shaft.

I used a nylon brush to scrub them with petrol three times. The first time the petrol was black after the washing. The third time it didn't change color.

The workshop manual showed the length of the clutch springs to be 1.75". One was. The other two were shorter but no two were the same length. LaNelle at Jack's had Barnett springs in stock for $11.50. She also had the o-ring for the shifter shaft.

Tomorrow I'll finish the installation and adjustment.

Al

Good deal. Sounds like you are well on your way to happy motoring.

Well, I'm feeling good about the bike, Grandpaul, but we've still got a way to go.

Next on the list is to finish the brakes. I have all the parts I need except for the banjo bolts and the male-male adaptors.

I just had an influx of some cash, so I can order them today.

Remember that the tires look new, but they are about twenty-five years old. I want to replace them. As a long-time BMW rider, I've become enamored over the years with Metzler tires, but I'm reminded of a mistake I made years ago in Europe and would like your opinion.

When I bought my first BMW in Germany, my experience was limited to British bikes. I had been a fan of Dunlop TT100s. A friend made a trip to England and brought back a set that could be fitted onto the wheels of my R75. Problem is that a high speed wobble would scare the hell out of me at speeds over 100MPH. Blaming it on the parabollic design of the Dunlops, I took the advice of a German BMW dealer, switched to Metzlers and the problem was corrected. It was an expensive lesson. I'm worried that Metzlers on a Triumph might cause similar problems.

Does anybody have experience or an opinion on this? Recommendations of tires I should use?

Al

Tulsaalva said:

Does anybody have experience or an opinion on this? Recommendations of tires I should use?

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I don't believe that fitting Metzelers (although you don't say which type?) is likely to cause any handling problems on your Bonneville if they are what you prefer?
I am also a long- time BMW R75/7 (& K100RT) owner, and well remember the warnings given during the seventies and eighties not to use Dunlop TT100 tyres on BMWs, and I have always used either Metzeler or Conti tyres on my BMWs. The new Avon Roadriders seem to be liked by British bike riders?

The tires fitted now are Avon Roadrunners. Don't forget this is a T140D Special. The front tire is marked with both 100/90H19 and 4.10H19. The rear is marked 110/90H18 and 4.25/85H18.

The 25+ year old Avons have hairline cracks running around the sidewalls and have to be aired up often. They're rubbish, I'm afraid, even though the tread appears to be unworn.

Al

I like the new Avon RoadRiders and/or the Dunlop 501 series tires.

The clutch is all pretty and clean and works great!

Let's talk about brakes... I just finished rebuilding the rear caliper. My question is: The Factory Manual says not to separate the two halves and, if one does, to consider it a temporary cure. The calipers should be sent to the factory to be rebuilt. They also say that torque is critical. Nothing is said about thread lock although it seems apparent that it was used at the factory. There is a round dot on the side of the threads.

The rebuild kits I bought contain the seal for the junction of the two halves of the calipers. The caliper went together nice and clean, new seals throughout, everything lubed with DOT-4, and torque was set half-way between the values quoted in the manual.

Since sending the calipers back to the factory may be problematic, how much trouble am I in?

Al

Tulsaalva said:

Since sending the calipers back to the factory may be problematic, how much trouble am I in?

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I believe the factory was just playing safe?

If you've done the job correctly then you shouldn't need to worry.

Calipers are one piece bodies. Surely you are talking about the master cylinder?

I read a good overhaul guideline for M/C, I'll see if I can dig it up.

L.A.B. said:

Tulsaalva said:

Since sending the calipers back to the factory may be problematic, how much trouble am I in?

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I believe the factory was just playing safe?

If you've done the job correctly then you shouldn't need to worry.

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That's my guess, too, LAB. Of course, we'll keep a careful eye on them for leakage when we put the bike into service.

Thanks!

Al

grandpaul said:

Calipers are one piece bodies. Surely you are talking about the master cylinder?

I read a good overhaul guideline for M/C, I'll see if I can dig it up.

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These Lockheed calipers (1979) are definitely two pieces, Grandpaul. Each side contains a cylinder and piston. They are held together by two bolts. There is a passage between the two sides, sealed with a rubber o-ring, to allow fluid to flow to both sides.

The Factory manual said not to separate them but I found it impossible to get both pistons out without doing so. I'm here to tell you it would have been even worse to install the pistons with the new seals without having the sides apart. It was tough enough as it was because the pistons (and the outer seal!) had to be perfectly lined up with the cylinder to get them to go in. It wasn't easy! I'm embarrassed to say how long it took me with a myriad of repeated tries before I was able to slide them home "gently" as the book said.

Al

Incidentally, I found no difference between the parts I removed from the caliper and the master cylinder and the parts I installed. The bike has 14,000 Kilometers on the odometer.

Edit: Actually, I guess there was one difference. The fit of the caliper pistons was tighter (not overly so) with the new seals than it had been with the original ones. I guess that's to be expected.

I'm pretty sure I could have just flushed the system with new brake fluid and the brakes would have worked fine.

Since I'd already bought the parts, though, there was no reason to not use them.

Al

Tulsaalva said:

These Lockheed calipers (1979) are definitely two pieces,

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Yes, the Triumph Lockheed cast steel calipers certainly are two piece units, and were so from when they were first used in 1973. Unlike the Norton Lockheed type.

Wierd, every Norton Lockheed stamped CALIPER I've rebuilt is one piece, with the threaded lugs for mounting only 1/2 depth of the cast body.

Am I totally wierd, or what?

grandpaul said:

Wierd, every Norton Lockheed stamped CALIPER I've rebuilt is one piece, with the threaded lugs for mounting only 1/2 depth of the cast body.

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But neither Tulsaalva or myself were referring to the NORTON Lockheed caliper? Which is totally different to the CAST STEEL Triumph caliper. As I said, "UNLIKE the Norton Lockheed type".

The bike in question being a TRIUMPH Bonneville T140D.

AH! You got me! This is a Norton forum, but I forgot we were on "other brands" section.

Okay, employing my best Gilda Radner as 'Emily Latella':

"NEVER MIND".

I'm hoping UPS brings some banjoes and banjo nuts, today. Tomorrow is more likely, though.

MASTER CYLINDER:

I've replaced the rubber parts, inspected the pristine bore, and reassembled the front master cylinder. I've found that the two parts screw together much more easily. Should I use some sealer on the threads?

Al