"BRIT IRON" takes you behind the scenes at

July 2011 - Issue #2

* I work on my Bike
- My '79 Triumph T140D needs some things...heck, it needs everything! Join us for bruised knuckles & beer!
* We're riding to the San Luis Obispo Show, Oct 6-9 - And we're riding Classic British Bikes! Wanna' come?

Hello again everyone. Hope you liked the first issue of "BRIT IRON", Classic-British-Motorcycles.com's online Electronic Magazine (e-zine), and my own personal venue through which to vent my endless ramblings. If you did not receive our first 'Inaugural Issue', fear not, you can still get a back issue. And as you may recall, just for subscribing, you are entitled to a gorgeous downloadable 11X17 color poster of a stunning 1970 Egli-Vincent. If you haven't yet claimed yours yet, here's the link:


Just take or send the file to a local copy shop with a good quality color copier & have them print it on heavy stock with a glossy finish for the best results. Of course you understand that this is a copyrighted piece & that you are being granted permission to run only 2 copies for yourself, no more for any reason. And you may not give this link away to anyone either. Please respect our copyrights. Enjoy...

CBM's Project Bike, my 1979 Triumph T140D Bonneville Special, has been reliable enough, in fact, totally reliable, willingly starting in one or two kicks, almost no matter what (except when I forget the kill switch is off). But, it really has never run very well. After retuning the Amal MkII carbs (smog dogs) to the richer European specs, I set the needle & the air screws in their respective midpoints & I've been screwing with it every since.

Granted the bike has 37,000 miles on it & it's pretty well worn. The pistons are clanging like cowbells, but it doesn't smoke. And of course they built these post-1978 bikes to pass stringent US & European emissions & noise laws, and to make an antique like the venerable old Bonnie pass, they had to go soft on the cams, the compression & the mixture, plus they choked off the exhaust. So, is it any wonder that it's such a GUTLESS WONDER!?

Since it was running soft, I thought I'd richen the mixture by moving the needle up one notch. Like an idiot, I moved the clip on the needle instead which actually moved the needle down, not up, thereby leaning it out even further. This mind you, the night before leaving for the Quail Ride. certainly better than before. But then it started missing & stranded me 4 times before I was able to nurse it home.

Turns out I was running out of gas. Got that one solved, then took off for another ride. A mile from my house I opened the throttles wide open & the bike started to cough & never ran right again after than. I think the needles were too high up & at full throttle they almost pulled out of the jets, thereby flooding the engine with gas & fouling the plugs. A new set of plugs & moving the needles back to the middle position, and after all my trouble, I was back where I started to begin with. Oh well, maybe it wasn't running that bad after all.

There's no question the clutch needs help. It doesn't even start to engage until the last 20% of lever travel. So, here we go, not so deep inside the bowels of the primary case.

Tear down was a snap. How many times have I done this in my life? Once inside, I was happy to see what looks to be a nearly new triplex primary chain. I was expecting it to be stretched & worn out by now. Obviously, someone had been in here before & swapped out the old chain. But that's not all they changed.

The T140D's former owner was an older gentleman who had gone to great lengths to prolong his being able to ride it. He had the kickstart mechanism geared down to make it easier to kick. And he replaced the stock clutch with an aftermarket 7-plate clutch. When I first took it apart, I thought I'd miscounted. "7 friction disks & 7 steel plates...wait, that can't be right." Of course, I'd just picked up a new set up plates & disks from the friendly & knowledgeable folks at Raber's Parts Mart in San Jose CA, and I distinctly remember getting 7 friction disks, but only six plates. I counted the new ones, 6 & 7. I recounted the old ones, 7 & 7. What the heck? The manual said nothing of it (it wasn't a factory item), so I went online. Before long I found an article on the '7-plate clutch conversion' that was supposed to ease clutch effort on the later Bonnies. Makes sense. The prior owner would have wanted that.

The article talked about the same things that I observed: that they were all thinner (of course, you've got to fit one more plate into the already-crowded clutch basket), and that the friction disks were themselves of a much smaller cross-section than the stockers, because the inside diameter of the friction disks are much larger than stock. The picture above shows how the new, stock friction disks on the right are much 'fatter' & thus have much more friction surface, than the old ones on the left. Notice the wear marks on the accompanying steel plate, it only makes contact around the outer half of its total surface area. It doesn't look like it would have much grip. I'm surprised, actually. But, either way, out it goes!

The machined grooves, or 'lands' in both the inside of the clutch basket & the outside of the clutch hub have taken a hammering. The clutch disks' & plates' tabs ride in these grooves & over time & many miles of punishing vibration have beaten grooves in the sidewalls of the grooves (see arrows). These should be nice & smooth & straight, instead they are wavy with jagged corners. In use, this causes the clutch disks to hang up & fail to disengage smoothly. This may be what caused the old guy to go to the softer clutch to begin with. What it needs is a file, and some elbow grease. I've already cleaned up the grooves in the clutch basket. But the ones in the hub are proving more difficult. Perhaps this will have to wait for another day...

The Third Annual San Luis Obispo Classic Motorcycle Show is coming up on Thursday through Sunday, October 6th through 9th, 2011, on the California Coast in San Luis Obispo CA. Sponsored by the Central Coast Classic Motorcycle Club, it's a dynamite show, swap meet & event. Racing legend Eddie Mulder will be there, and so will "The World's Fastest Indian".

As usual, a large group of Classic British Motorcycle enthusiasts (read that: Brit Bike Nuts) leave Raber's Motorcycle Shop in San Jose CA, chase trucks following behind with tools, parts & trailers, if needed, plus all our crap. It's about 200 miles each way & we try to take backroads for most of it, as few freeway miles as possible. For me, the ride is the best part. We'll stay at an economy motel down there & have a blast for 4 days looking at gorgeous classic bikes, then we'll ride home again.

If you like to ride, and you love adventure, maybe you should join us on this one. The backroads, the coast, the bike show, and of course, the company will make this a killer 4-day weekend. If you'd like more info on the trip, contact me.

Until next time, enjoy this great riding weather.

All the best,
Andy Tallone