Sunday 29 March 2020

Everyday TR1 - dialing in carbs and improving everyday usability

With the first gentle rises of temperature (read that as in, it was frigging cold yesterday and today it's steaming hot), it was time to start waking up all the other bikes in the workshop. Most interesting to me, of course, find out what that new TR1 engine was like.

I am also especially happy to report, that smearing some rtv-sealant around the base of the oil-pressure sensor finally did the trick and it has stopped leaking. 

But I did notice that it wasn't quite idling very well and also after the first "spirited" break in ride I noticed a somewhat weird hesitation below 3000 RPM. O2-sensor o'clock! (Yes, it's running off a separate battery and because said battery is a bit knackered it's also running off a charger... quality engineering at its finest.)

13.8:1, or in other words, I have developed a perfect lean-burn engine. (All of a sudden, I am happy to have stopped at my workshop and tackled this issue immediately, because this could have ended very, very ugly.)

There were multiple iterations of this, but I ended up installing bigger pilots (#20) and later on also a bigger air-jet (#0.7), because it ran pig-rich on the needle and then was fine at the very top. I can only attribute this to swapping back to the stock ignition box and the Ignitech truly being more than just a bit unhappy, before it finally died in Winter. 

And then there was this stumble off idle and some VICIOUS engine vibrations under 3000rpm, when you opened the throttle. (Paired with a distinct lack of power.) Turns out, it was mostly running off only one cylinder until the other one kicked in. It was only a minor misadjustment, which is why I originally didn't trace it back to carb-sync.

With the engine running like it should, it was time to do something a lot more mundane, fitting a 12V power-outlet to the bike, so I can power a satnav or (more importantly, once I've got a plug for it) power my o2-sensor and finally use it under load. Also it will double as a socket to charge the battery.

I've long been running a spade-fuse instead of the stock fuse holder, so I added another cable (on the fused side), with a round contact so I can (easily) get the loom out when I have to take the bike apart again.

In case you're wondering – after running into a series of batteries failing prematurely, I started putting the start-date of their service-life on them.

Don't you find it weird, that I go through all this trouble and don't shed a word on how the engine now performs...? There's something cooking in the old engine-building kitchen.

Saturday 14 March 2020

Project Volksrad - a watercooled beetle with only two wheels

Sometimes you fall over project-bikes, which are so unlikely and even more so, if they come in at an affordable price. And then the story becomes really interesting, when the person you least expected it, wants to actually have and ride it. Or in other words: I never thought my dad would turn into Goldwing'er.

Of course, for it to be in (my) rather limited budget range it had to have "a little" flaw. This one was in parts and it was a GL1200, which is the last of the flat-fours and has got a bit of the ugly duckling stigma to it.

Now the first thing you notice, when working on one of these: It's huge. Everything about the overall dimensions on this bike is somewhat enormous.

Strictly speaking, the bike itself isn't too bad, but once the pannier rack (the huge chromed bit of pipework) is fitted the overall dimensions are incredible.  

Fitting the swingarm was the first real challenge in re-assembling the whole lot. Unfortunately when the bike was painted, the swingarm-locator-pins got some paint on the bearing surfaces, so a bit of lathe-polishing-action was necesary.

The locating pin for the right rear-shock needed a bit of modification. In order to make it easier to slide-in, a slight taper was added as the stubborn little thing just didn't want to go into the thread on the final-drive housing.

 The other side was comparatively simple, you just have to be aware that the end of the bolt is also the locating pin for the rear brake-caliper holder.

Tank put on to get an idea. My dad wants to strip it from all the fairing bits and I do agree, a naked Goldwing does have some appeal and looks by no means as massive as the fully dressed version. 

As a next step it was time to turn to the engine and have a look at the things that I know are amiss on this one. First a quick glimpse under the skirt... Belts (obviously) need replacing, but the water pump still looks good. Also removing the covers allowed me (later) to slip the engine into the frame. (I know the manual says it's not necessary, but it was those extra few millimeters that counted in the end.)

One of the few things I knew that I would have to tackle was the clutch slave-cylinder. It had been leaking for quite a while and is an absolute nightmare to get to when the engine is installed. 

This picture was taken AFTER the all the dried up brakefluid was cleaned out. A thorough and long-winded cleaning and polishing session followed.

The piston hadn't fared much better, but after a bit of polishing it came out as good enough. If it really needs to be replaced, I can easily copy it in stainless.

And that's the whole clutch-slave being re-assembled and working again. 

With the clutch slave out of the way, the other problem I was reported was that the bike wasn't charging all that well anymore. Didn't matter much to the pre-owner as he mostly rode longer distances. I admit, I was slightly worried about that as the alternator is a rather special item, which is sold for  a rather premium price. (To be fair, a belt driven car alternator was on my list as potential fixes!) It was much more simple than that though.

Luckily all the plugs are (relatively) DIN- or Japanese standard these days, so replacing the odd mangled plug isn't all that bad anymore.

What's much more annoying is the fact that over Christmas (most of these pictures were shot on the 23rd of December), I lost all the pictures of the engine re-installation. Which in some way is fine, because it was an absolute b*st*rd job. Should you be in the same situation: Remove the belt cover, this gives you about 10-15mm extra. Also unlike the factory manual states, the short end of the shaft-drive coupler goes towards the rear-wheel or otherwise you're lacking about 5-6mm to couple the splines. And it has to be put into the swingarm first. Don't even bother about installing the engine and then fitting it all up afterwards as I can't see how (again) you're going to fit the coupling. The rest is fairly simple, just hook it up to the frame and that's it. Use a car jack to lift and level out the engine and it's quite doable.

Next stop: electrics and probably a first start.

Saturday 7 March 2020

Phour days to phantastic - it's all the little things (day 4)

There's this saying that the last 20 percent of a project take up at least 80 percenty of the time. Well, it wasn't the case here to be honest. The lil' CX still had a few fleas, of which the most worrying one was the state of the wiring as it used to be a police bike back in the 80ies, so it had a lot of extra equipment on it.

But first things first: the original petcock has officially had it and a new one had to be installed.
(And yes, this is the stock police tank. Looks like they simply repainted the bikes at the importer. The headlight-cowl has got some blue underneath the white paint.)

After the first testride I found out that the forks were a bit twisted, but that was sorted rather quickly and unlike my first assumption the frame appears to be pretty straight for a 70ies bike.

Time to dig into the electrics - someone cut the wires going to the front indicators, which is a pretty good reason for them not to work. 

The most tricky part of all was to work out, why the tail-light worked just fine, but the headlight didn't. Turns out, the high-beam switch was corroded and cut all the electricity to the headlight bulb.

Now this is officially not pretty, but a fuel-filter does wonders in keeping the dirt out of the carbs and preventing carbs from overflowing. (We – as in my dad and I – rinsed the tank multiple times, but there's still some fine rust-debris in there, so over the course of the next three or four fills this will probably mostly come out.)

And there you have it: a nice little CX500, which still isn't pretty, but everything works and it will make a perfect little everyday runaround bike. Even the charging system works just fine, with the reg/rect shutting off. (That being said, the charging system is VERY stout as even with lights on at idle it can charge the battery. Something I am not sure any of my bikes can do...)

Really curious, what my dad will have to say about it. It's a lot more nimble than I would have thought. Carbs may still need some tweaking, but then again it also was very low on petrol and not fully warmed up. Valves might need some attention too as they made some tickering noises, but then again heaps better than nothing to hear at all. All in all, I am quite chuffed with the little bike and the work we put into it.