1978 Bonneville T-140V

[Frank]

Hi Everyone

My 28 year old son talked me into going with him to look at a 1975 Honda cafe racer about a month ago. While we were there I spied a 1978 Bonneville and fell in love with it. My son has yet to take the leap on the cafe racer but I brought my Triumph home about a week ago.

I just started riding about 4 years ago. I learned on a 2002 Suzuki GZ250. I was sure I would be happy with that. Ha!

My Bonneville has been in storage in Wisconsin since 2000. It was brought to Florida by the man I bought it from for resale. Fortunately I saw it before he got around to cleaning it up or putting any more money into it.

It is a 140V, not a "smog dog". It, as you all know, oil-in-frame. Is that a bad thing? Are they frowned upon?

Before I can get it on the road I have to take care of a bad rear brake, front fork seals and figure out the tuning of the carbs.

The owner's manual that came with the bike is for a '79. It's totally wrong for this bike as it's different carbs, different ignition, etc. Will anyone here be able to help me with an owner's manual for a '78 pre-EPA changes?

I look forward to my new adventure and getting to know you all.
-Frank

 

[CarlS]

The OIF (oil in frame) is not a bad thing. The Bonnies and TR's with the oil tanks are a little more desirable; but these are becoming harder to find. More folks are rebuilding the OIF bikes. There is nothing wrong with them at all.

I am sure GrandPaul can steer you to an owner's manual for your bike as well as tell things to check and look for.

As you rebuild it, take photos and document what you are doing. Then post all of this in this thread. We love to follow this stuff. We would also like to pics of it as is. I wish you the best with your project. The classics Triumphs are fun and rewarding - as well as frustrating and aggravating!

 

[The Seeker]

It is a 140V, not a "smog dog". It, as you all know, oil-in-frame. Is that a bad thing? Are they frowned upon?

Actually, I bought a T140V BECAUSE it's safer to ride on today's roads with the turn signals and disc brakes. I had a 1969 650 Tiger already but I don't ride it in today's traffic.

The 750 over 650 and the 5 speed gearbox is nice to have too.

I posted an old review which states that the OIF bikes were the best of the Bonneville.........Classic Road Test: 1973 T140 Bonneville

Here's a 1978 T140 Owner's Handbook in PDF format to download. (Click to view it, right-click to download it)

I too have a '78 T140V so speak up for any help!

 

[Frank]

Seeker, thank you for the owner's manual. It's much closer than the 79 one that I got with the bike.

Later today I will attempt to load photos of the before and after for cleaning. Just a simple wash made a huge improvement.

Off to do other chores now.

Later,
Frank

 

[CarlS]

Looking forward to the pics




.

 

[grandpaul]

I just recently posted somewhere, that one of the WORST jobs on a classic Triumph is overhauling the rear disc brake master cylinder. You must remove the rear wheel assembly, all of the right side engine mount, brake pedal, and all the other appurtenances to get that ghastly gremlin free from the frame. About 70% of the time, the bore of the cylinder itself will be rust pitted and must be replaced. Almost certainly, all rubber brake hoses MUST be replaced, front & rear. Whether you got one of a few rare ones with no damage to the brake master cylinder innards or not, ordering both rebuild kits is relatively inexpensive, and gives you peace of mind.

 

[The Seeker]

I was lucky in that both front and rear master cylinders were fine when I bought mine a year or so ago.

I did replace the rotors since they were very badly pitted. They worked just fine pitted, but it looked really bad that way.

 

[Frank]

I am just not very computer savvy. Here is one photo as an experiment. Is it too large or small? Did I use the proper procedure to post it?

More to come if I did ok.

Frank

 

[The Seeker]

Yessir, everything is A-OK with your photo posting!!

 

[DaveM]

The bike is looking great

 

[The Seeker]

The previous owner sure liked to paint stuff yellow, eh?

By the way.....those loose turn signals are a bugger to tighten-up. If the shaft isn't loose, then it's the bolt INSIDE the turn signal housing. After removing the lens, you then remove the two screws holding the bulb-holder and reflector in place. Then you'll see the large nut at the end of the shaft. What makes it tough is finding a wrench or pliers that will fit around the head of the nut while still fitting inside the housing.

 

[CarlS]

Thanks for the pic. The bike looks mighty fine.

 

[Frank]

Yeah, I don't get the yellow bolts and plugs and the plug wires. The bolts I will replace with stainless and the plugs I will have to remove the yellow paint.

Was there ever a factory yellow like this? Or is it common to have custom colors on older bikes? The tank is very nicely painted but the side covers have tape instead of hand pinstriping.

I finally figured out how to load photos into an album so there are more to see now. I thought they would show here, too but I don't see them. Oh well, one step at a time.

Frank

 

[DaveM]

I cannot recall there being a yellow on the older bikes

 

[The Seeker]

Harley guys used to use the bumblebee yellow plug wires quite often. I never saw it done on a Triumph before.

I'll bet you could just clean the yellow paint off of the bolts.

 

[grandpaul]

The photo is fine; the yellow paint, not so much...

 

[Nige W]

The only yellow ones were the Tiger Trail model - did anyone really buy one of those? Yes, lose the yellow, pronto - it'll run much better.

 

[Frank]

Well, I've been plugging away. I ended up with a no spark situation with my boyer ignition. I finally replaced the black box and that fixed it.I've been working on the rear brake. I had the wheel off to bleed the caliper properly so I decided to rebuild the caliper. I have put it back together 3 times only to have the inboard piston leak every time. (it was not leaking before I rebuilt it.) What's happening is the metal ring that gets pressed in last is not tight enough and ends up being pushed out when the brake is applied. Is there a trick to this? The other side is staying put just fine. I have one more 1/2 kit left to do it again but I'll wait for pointers first.

 

[DaveM]

Well if anyone can tell you it will be GrandPaul as I am sure he must have done a few in his time

 

[grandpaul]

Did you use new o-rings in the caliper?