Bringing My '79 Bonneville Special Back to Life

You could try tying the clutch lever back to the grip when the bike isn't going to be used for a while, as that would take the spring pressure off the plates and may stop them sticking? I'm not sure I'd want to be hitting the lever with a mallet on a regular basis?

Surflex plates are an aftermarket kit and should be available from British bike parts suppliers? From what I've read on other forums, many US T140 owners seem to have a poor opinion of Barnett plates!

To quote one owner's opinion (member sboyd) from the BritBike Forum:"I would get new plates anyway for sure as long as you're in there. Recommend MAP or Surflex or even Emgo, anything but Barnett.
Lots of low mileage T140's have the original plates and they look great, but they're way too sticky and hard to free-up. If you free it up by jamming it into gear as some have recommended on other threads, sooner or later something real bad will happen."

L.A.B. said:

You could try tying the clutch lever back to the grip when the bike isn't going to be used for a while, as that would take the spring pressure off the plates and may stop them sticking? I'm not sure I'd want to be hitting the lever with a mallet on a regular basis?

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I didn't mean to give you the impression that I was severely beating the lever, Les. I've often used a similar technique to loosen rusted bolts. My experience is that pulling hard or using an extension to remove a rusted bolt (there are none on the Bonny) often results in breaking the bolt in it's threaded bore. By fitting a socket with a straight handle and tapping on it, a rusted bolt can often be loosened without damage.

That's the same idea with the clutch. I held the kick start lever aft to take all slack out of the mechanism and hit the lever itself repeatedly with the plastic mallet. I suspect the vibrations caused the "glue" to let go.

I wonder if tying back the lever would eventually weaken the clutch springs? I think the answer, if the plates continue to stick, is definitely new plates.

Surflex plates are an aftermarket kit and should be available from British bike parts suppliers? From what I've read on other forums, many US T140 owners seem to have a poor opinion of Barnett plates!

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I think I'll take Grandpaul's advice and buy the Emgo plates as soon as I can find a place to do so. The local British Bike shop seems to only carry Barnett and are sold on them. If they're as good as Russell brake lines, I'll go for anything else.

To quote one owner's opinion (member sboyd) from the BritBike Forum:"I would get new plates anyway for sure as long as you're in there. Recommend MAP or Surflex or even Emgo, anything but Barnett.
Lots of low mileage T140's have the original plates and they look great, but they're way too sticky and hard to free-up. If you free it up by jamming it into gear as some have recommended on other threads, sooner or later something real bad will happen."

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That sounds like a fine way to destroy a transmission, or at least a gear. I like the idea of jamming it into gear only a little better than placing the front wheel against a curb and doing a burn-out. I certainly don't like either one well enough to try it!

We no longer have a real Triumph dealer in Tulsa. Does anyone know an on-line supplier of Triumph parts? I'd consider a reputable place in England. I just bought a new camshaft for my 928S from an English Porsche dealer and saved a lot of money over ordering one from Germany through a local dealer. My car is a European model. The cams fitted to the American models are quite different.

Thanks for all the valuable help!

Al

Speedometer malfunction

As I said earlier, the Speedometer on my T140D doesn't work.

I removed the cable at the instrument and rotated the rear wheel. The cable end does not turn. Therefore, I must assume the problem is either with the drive or the cable. Either may be broken or I may not have fitted the drive properly at the rear wheel.

I have been unable to find any mention of the speedometer in the manual. As you know I'm still using the "78 and earlier manual but I feel certain that Triumphs built prior to '79 have speedometers, too.

I hate to get out the lasers a third time, but I think I'm going to have to remove the rear wheel to find out what the problem is.

Al

Tulsaalva said:

I wonder if tying back the lever would eventually weaken the clutch springs?

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The clutch springs are always under compression. A rough measurement of clutch lift only puts them under 0.110" or so extra compression? Even tying the lever half-way back would probably be enough?

Tulsaalva said:

That sounds like a fine way to destroy a transmission, or at least a gear. I like the idea of jamming it into gear only a little better than placing the front wheel against a curb and doing a burn-out. I certainly don't like either one well enough to try it!

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The way I'd try to do it would be to start up with the rear wheel clear of the ground (on the stand) and then select either 1st or 2nd gear, rotating the rear wheel by hand if necessary as the gear is selected, then pull the clutch and rev it up, with the rear wheel still clear of the ground as it will be spinning, and then apply the rear brake sharply several times, using throttle to keep the engine from stalling, until (hopefully) the clutch frees off?

Tulsaalva said:

We no longer have a real Triumph dealer in Tulsa. Does anyone know an on-line supplier of Triumph parts? I'd consider a reputable place in England.

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There's plenty of Triumph parts suppliers to choose from in the UK, and I'm lucky that I only live three miles away from one!
But I would have thought you could get everything in the US from Rabers, Klempf, British Only, Britcycle and others?
(A certain "British parts supplier" in the Chicago area is best avoided)

http://www.rabers.com/

http://www.klempfsbritishparts.com/

http://www.britishonly.com/

http://www.britcycle.com/

Grandpaul probably has some other suggestions?

The Bonny has been running well until two days ago when it quit while Sixteen was driving 40 MPH down the street. He was able to coast the bike into a neighborhood where a fellow with a pickup truck gave him and the bike a ride home.

The first thing I found was a loose battery cable connection so I tightened it up.

This afternoon, we started the bike but it only runs on the right cylinder. The left side of the engine and the exhaust pipe remain cool to the touch. I cleaned the sparking plug (which seemed wet with fuel) but it did no good. All connections are tight.

The bike has the factory electronic ignition system. Is it likely that only one side would fail?

I have not yet checked compression but will do that next. I have two spare new coils. I also have a new spare electronic ignition module.

Does anyone have any suggestions on how to troubleshoot the problem?

Al

Volt meter.

grandpaul said:

Volt meter.

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Thanks, Grandpaul.

Unfortunately your response suggests I'm smarter than your average hick Okie. I do, however, own a voltmeter.

Al

Tulsaalva said:

This afternoon, we started the bike but it only runs on the right cylinder. The left side of the engine and the exhaust pipe remain cool to the touch. I cleaned the sparking plug (which seemed wet with fuel) but it did no good. All connections are tight.

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Did you actually test for a spark by fitting the plug to the plug cap of the bad cylinder and touching it against the cylinder head while kicking the engine over?

What type and grade of plugs are they?

Tulsaalva said:

The bike has the factory electronic ignition system. Is it likely that only one side would fail?

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Electronic ignition systems for these bikes (such as Rita/Boyer) normally work using the "wasted spark" system, where the (2x 6V) coils are wired in series, and so produce a spark simultaneously at both plugs once every engine revolution, each alternate cylinder's spark being wasted.



Both coils are connected in series to the same box circuit wire, and both use the same trigger circuit, if the box or pickup develops a problem then that will affect both cylinders.
Therefore the parts that could fail and cause a problem on only one cylinder would be: coil/plug wire/plug cap/spark plug. Try swapping those parts over one at a time and see if the problem swaps cylinders?

I did do the test for spark that you mention, Les, and there was none on the left side.

Previously, I ran a compression check. It was fine. No leak down.

Great idea on changing over the parts! I'll start with new plugs and then swap the plug wires. If the problem persists, I'll change the coil.

Thanks!

Al

Al,

What type/heat range plugs are they?

The plugs are NGK B7ES, Les.

Al

Tulsaalva said:

The plugs are NGK B7ES,

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Then I'd certainly swap/replace the plugs first, as the original recommendation for the parallel inlet heads (E, & D models etc.)was for Champion N5 plugs, which cross-references to NGK B6ES.

I just called LaNelle. She told me the T140D uses Champion N5 plugs and she has them in stock!

She's open until 4PM on Saturdays. Talk to you later!

Al

I also ran a continuity test on the spark plug wire with my ohm meter and got .000. A continuity test on the NGK plug, without bridging the gap showed .044.

Al

If you Ohms check the coil connections, do both coils give similar readings?

There should be no continuity between any coil terminal and the coil casing.

Plug caps, if "resistor" type should be 5 kOhm (5,000 Ohms).

After changing the plugs for the proper Champions the bike started on the first kick and Sixteen rode off to work, a few minutes later than he would have liked. I thought the bike wasn't running as smoothly as it should have done as he headed down the street, but he didn't stop. Since there was no telephone call from him, I'm guessing he made it okay. The engine may have not been warmed up enough to sound really smooth. I may drop by the convenience store where he works this afternoon and ask how the bike ran.

The tachometer had stopped working. Do you reckon I disconnected something in my efforts?

There is no resistance at all in both spark plug wires. The ohm meter reads ".000."

With one lead on the top of the plug and the other on the cylinder head, the ohm meter read 1.00 with the new Champions installed.

There is no continuity between any of the wire connections and the canister of the coils.

I think I had nothing more than a failed or fouled sparking plug.

Many, many thanks, Les, for the guidance!

By the way, in the factory manual, in the section on Sparking Plugs, one can read that torque is important. One should look under general data for the proper torque values. However, there is no value for sparking plugs listed there.

I checked the BMW manual. The plugs are the same thread and reach, and torque from 15.5 to 20 foot pounds is recommended. I chose 18 for the Triumph but would really like to use the value recommended by Triumph.

I wonder if I could find an Owner's Manual for the T140D?

Al

Tulsaalva said:

The tachometer had stopped working. Do you reckon I disconnected something in my efforts?

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Either (1) The cable is broken? (2) the tacho unit is not functioning for some reason? (3) the drive box isn't driving the cable?

Tulsaalva said:

There is no resistance at all in both spark plug wires. The ohm meter reads ".000."

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By saying "spark plug wires" if that includes the plug caps, then they will be non-resistor type? But it doesn't matter with the Rita if they have resistors or not, the ignition system will be producing some TV/radio interference (RFI) without resistors.

Tulsaalva said:

I think I had nothing more than a failed or fouled sparking plug.

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That was my thinking, as the engine appeared to quit fairly rapidly, many D & E owners being unaware that their parallel head models use the hotter N5 plug. But if the problem re-occurs then change the coil/wire/cap.

Tulsaalva said:

By the way, in the factory manual, in the section on Sparking Plugs, one can read that torque is important. One should look under general data for the proper torque values. However, there is no value for sparking plugs listed there.

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I'm not sure there ever was a recommended spark plug torque figure?

Tulsaalva said:

I wonder if I could find an Owner's Manual for the T140D?

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It should be easy to get a copy of the later '79-on manual, which contains information more relevant to your D model?

L.A.B. said:

Either (1) The cable is broken? (2) the tacho unit is not functioning for some reason? (3) the drive box isn't driving the cable?

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Of course! I was thinking the tach would be electronic... "Of all the things I've ever lost, I think I miss my mind the most."

By saying "spark plug wires" if that includes the plug caps, then they will be non-resistor type? But it doesn't matter with the Rita if they have resistors or not, the ignition system will be producing some TV/radio interference (RFI) without resistors.

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Since we don't have a radio on the bike, I'll only worry about this if the neighbors complain that their TVs go haywire when Sixteen rides by.

That was my thinking, as the engine appeared to quit fairly rapidly, many D & E owners being unaware that their parallel head models use the hotter N5 plug. But if the problem re-occurs then change the coil/wire/cap.

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Sixteen said the engine became smooth after a couple of blocks and by the time he entered the main thoroughfare was running better than it ever has. He thinks it starts easier, too, but only has kicked it to life twice since the new plugs were installed. We'll keep an eye on it.

I'm not sure there ever was a recommended spark plug torque figure?

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Okay. I'll stick with 18 foot pounds, Les, unless you have another suggestion.

It should be easy to get a copy of the later '79-on manual, which contains information more relevant to your D model?

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I'll ask LaNelle if she can get one through her contacts.

Many, many thanks for the help, Les!

Al

I found an owners manual for the Bonny at Rabers and have it on the way along with a clutch kit. We're really tired of dealing with the hassle of freeing up the clutch plates. They stick if left overnight.

Nineteen doesn't ride the Triumph any more. He prefers the BMW and simply drives his 944 if Sixteen is away on it, a situation that is happening more and more. We'll see if the new clutch helps. Otherwise, it looks like we'll sell the Special and use the money to buy another BMW. Sixteen thinks he'd like a K100RS.

I prefer the R80RT, but still love the Triumph for its history and heritage, not to mention the handling and sheer fun of riding it. Still, if either of my sons wants to go somewhere and a motorcycle will do, they ride away on the BMW and the Triumph sits in the garage while the clutch plates stick more firmly, I suppose.

I'll give the new clutch a chance before making a final decision, but I'm not going to just stick the Bonneville back in storage.

Al

I finally found time to fit the Triumph's new clutch plates. I finished in about half-an-hour. It's amazing how much easier a job is the second time!

Without the hassle of unsticking the clutch plates, Sixteen is now rolling the Bonneville out of the garage instead of the BMW. The bike does have it's charms!

Sixteen, a high-school Junior, is enrolled in a local technical college's motorcycle mechanics course. He attended his first class yesterday. It was all about safety in the workshop. He was sorely disappointed that he didn't get to disassemble an engine on the first day. He plans to go to college and is taking the course so he can earn more than minimum wage in part-time jobs.

Nineteen will begin classes next week at Tulsa University. He will be commuting the ten miles on the R80RT on Mondays, Wednesdays and Fridays. On Tuesdays and Thursdays he'll need to take his guitar and amp so he'll drive his car.

I have an '85 Porsche 928S, German model with a five speed and about 100 more horsepower than the American version. The value is appreciating rapidly. It's now worth about 2.5 times what I paid for it ten years ago. Often, when I read in "Excellence" magazine about what current models are selling for, especially the rare ones, I think, 'I really should sell the 928." Then I go out and drive it. My thoughts change to "I could never replace this car. Besides, it's the nicest car I've ever owned and it's so much fun to drive!" I think the Triumph may hang around for some time on the same terms. Another BMW just wouldn't be the same.

But I do need to sort out some of the electrics. Here are a couple of peculiarities:

The turn signals still don't work, but when the switch is activated, the trouble lights flash.

The bright lights' blue indicator is on when the dims are in use and off when the brights are selected.

I'm going to look inside the headlight shell today and see if any wires are connected erroneously. Any tips?

I once had a BMW which would start and run without the key as long as both brakes were applied. It would die if the brakes were released. I found two wires inside the headlight which were plugged in wrong. Matching the colors solved the problem.

Al