Last ride, no breakdown!

Whoa, that was a long break between posts, sorry about that.

But I've not been idle, far from it. Bagheera and I have been out riding regularly. Each time we go out a few less things fall off or break; and each time I get better at riding her. And each time when we get back we fix what has fallen off and broken and we have a better motorcycle.

If you read the last post, you'll know the first ride abruptly after two miles with a dead electrical system. The second went much better; until that is after about 15 miles when the red light flickered on -- I had lost oil pressure.

This is bad news. Many of the bearings in an engine are plain bearings, which means the only thing keeping the moving parts from griding together with great force and destroying each other in mere seconds is a few microns of engine oil. This oil gets forced out of the bearings and must be continuously replaced by the oil pump and distrubution system. When the system fails, the oil pressure drops and the little red light comes on to tell you that you are seconds away from writing off your engine.

The crankshaft is the heart of the engine. It has ball bearings at either end,
but the big end bearings are plain; only engine oil separates the parts.

I let her cool down, and found the oil light went out -- well it dimmed a bit -- and I could nurse her home with thankfully was only a short distance.

Once I was home, I could try to figure out what had gone wrong. Low oil pressure can logically only be caused by:

• Not enough oil in the tank. It wasn't that.
• Wrong oil - too runny. Not that either.
  
• Blocked or crushed oil feed pipe. Nope.
• Oil pump not working properly. Maybe, that's common.
• Oil escaping somewhere it should not. Perhaps.
• Oil passing through the bearings too easily, because they are knackered. I hope not!
• Oil pressure light telling lies. Tempting -- but no.

There is another golden rule, often forgotten, of home spannering. When something goes wrong after you fiddled with something else, however unrelated it may seem, then that is the most likely cause. 

I'd been fiddling with a lot of stuff, but one thing came to mind and that was the replacement timing side engine cover that I fitted back in this post because I cracked the original one. How can replacing an engine cover cause low oil pressure? Well, because the odd design of these Triumphs puts some of the oil distribution plumbing inside the cover and some inside the engine, with seals between the two. 

One seal is between the cover and the end of the crankshaft. If this seal does not, well, seal, then the oil pisses out directly into the bottom of the engine cases instead of going down the middle of the crankshaft into the main bearings. Especially when it is hot and runny. And then the light comes on.

Sure enough, when I remove the cover again I find the seal is not only damaged, but it is fitted backwards as well. This is a common mistake, because this is one of the very rare places where the seal is holding back oil coming from the outside in, rather than keeping it from leaking inside to out. So actually it has to be 'backwards' to be the right way around. No, I am not sure if I followed that sentence either.

It took a while to track down a best-quality replacement seal (this is not a place to put a cheap one), but thankfully it did the job, no need for an expensive new oil pump nor a full engine strip down to replace the main bearings.

On the third ride -- and I can't blame anyone else for this one -- the new number plate fell off and vanished. Because it was a bit flimsy, I had stuck it onto a piece of perspex but not clearly well enough. So I ordered a decent one from the experts Tippers Plates. Oh and also the clutch started slipping.

On the forth ride, she sounded a bit noiser than usual. When I got home, both of the nuts holding the left silencer on had fallen off, and so had one from the right. 

Then next time the battery strap broke and the battery bounced around in its holder, fortunately not quite wearing  a hole in itself and dribbling concentrated sulphuric acid everywhere.

On the penultimate ride, it got rather noisy again, but this time it was the fuel tank mounting rubbers coming adrift and letting it rattle against the frame.

But today I had a lovely hack around the Chilterns in the sunshine and nothing fell off. OK there was oil seeping out of quite a few places, and the handlbars had come loose, but that's not a breakdown, that just character.

I have also been quite busy with the spanners since the last post. I really wanted to improve the "pull-and-pray" front brake. After taking it all to pieces, I did find that the cast iron brake drum liner was coated with some sort of residue. It took some hours with various drill-mounted wire brushes, but I eventually got it back to clean metal (this is definitely a job for a decent dust mask, as otherwise it's a great way to get asbestosis.) And for good measure I fitted some new brake shoes from a good manfacturer and rerouted the brake cable to the most natural path, even though this does obscure the speedo somewhat.

And... it's a bit better. I think I can still get from 0 - 60 faster than I can get from 60 - 0, but give it a good hard pull with all four fingers and there is some noticable retardation. I guess I am just spoilt by the incredible brakes on modern Japanese machines.  

The clutch has had a good tinker too, to try to make the action a bit lighter. I took off the primary side engine cover, gave everything a good clean. I removed the pressure plate and clutch plates to reveal the shock absorber rubbers, which were in amazing conditions and must be quite new. The clutch plates too were just fine. After balancing the clutch springs to get a nice even release and re-oiling the cable the clutch action is now... exactly the same. Oh well. Still, I did find that the primary chain was a bit loose so I sorted that out while I was in there.

Finally, to upset the purists, I have installed a modern oil filter. The metal gauze fitted to the oil tank only stops largish bits and sludge from circulating, failing to trap the tiny abrasive particles and dirt that cause the engine to wear. Using a large exhaust clamp, a filter housing from a Norton Commando and a bit of welding, I came up with this, which I am rather proud of:

Hidden away behind the main frame, you can only see it if you know where to look:

Next time: impressions of riding a classic.

TOTALS TO DATE: Hours: 145. Cost: £6310. Miles ridden: 120. Breakdowns: 2.