Sunday 28 June 2009

First ride

The good news is it starts from cold on the second kick, and runs sweet as a nut! The bad news is it failed the MOT on my (not-so-clever) horn and the rear brake - too much travel in the pedal, and not enough braking. This had been a pain to set up and I left it in what I thought was a sufficient state, but obviously not.

To be investigated. Re-test booked for next Saturday.

Friday 26 June 2009

Light switch

So I'm ready for the MOT tomorrow, but at the last minute I noticed that the dipped beam wasn't working, only full beam. I checked the wires to the back of the bulb and everything was in place. I then partially removed the switch and found that if I jiggled it around a bit the lights would work, and then not work.

Dismantling the switch revealed some rather poor quality workmanship - more like a GCSE electronics project than a commercial automotive part. The dismantling process indeed revealed the problem (see later), but rendered the switch useless. I went round the corner to Fanatic to get a new one, armed with a multimeter to ensure I got a working one.

Now there is definitely a technique to getting the switch cable in through the throttle housing - remove the tough plastic sheathing so that the individual wires are loose and exposed enough to be fed through one by one and captured at the other side. I'd say its about 100mm or so. Then feed each wire through one by one, and when they're all through a combination of pulling from one end and pushing with a blunt instrument at the other end should get your wires through. Make sure when you're done the bulk of it sits in the recess to the front of the housing. Test your throttle, and if there's too much resistance from your light wiring then jiggle it around a bit more or even try some WD40.

So after fitting my new switch I had the same problem all over again - some settings work, some don't. But armed with some prior knowledge I now knew how to overcome this. With the switch fully fitted take each individual wire where it appears from the sheath and pull it hard. This pulls the wire within the switch housing so that it sits squarely back into its correct position where it should be soldered, but often isn't.

Problem fixed. Ready for MOT. Note to self: buy a better quality switch soon. :)

Tuesday 23 June 2009

Locking it up

The best you can do to keep your Lambretta where you left it is to lock it to something immovable with something impenetrable.

The something immovable bit is easy and obvious - lamppost, roadsign etc. The something impenetrable bit is a bit less obvious. The world of motorcycle security chains is peppered with marketing bull**** that is misleading at best. "Crop-resistant" is my favourite. It means absolutely nothing, and if you search on youtube it won't take you long to find videos of big-brand "crop-resistant" chains being cropped by hand with a pair of 42" Records.

A bit more research and you will find some smaller names producing some serious hardware that they guarantee is uncroppable, along with the youtube vids to prove it. Almax in particular are good at this kind of promotion, and you will find them mentioned on quite a few forums. However, I bought a 16mm Pragmasis Protector (www.torc-anchors.com), and my word it's a beast. It weighs a ton and as expected it isn't one for carrying to the shops with you. It is however the perfect chain for using at home and helping you sleep easy.




I have two locks for this chain. The 'Untouchable' is a unique, small, portable design and is available from torc-anchors.com, and The Oxford Boss Disc Lock Alarm is a more traditional padlock-type device with an inbuilt alarm system.

The fitting of a front disc gives you the option to use a disc lock too. The SPAQ/Sterling (same as ScootRS) discs have limited space for a disc lock, but after a bit of trial and error I found that one fits and works well - the Xena XZZ6 Disc Lock Alarm. It's strong, well built, loud, and portable.



I also bought an Oxford Nemesis to back this up - it too fits onto the front disc.

Friday 19 June 2009

Making the horn louder

This Lambretta is going to be used regularly, and almost exclusively around the city. For this reason I wasn't happy with the dull 'quack' of the AC horn which would frankly be useless on anything but the quietest of roads.

I did a bit of googling about how to resolve this, and everything I found referred to fitting a battery; the only way you can get a good horn sound at all revs is by having a DC horn.

I have no intention of fitting a battery, so a bit more googling and some high-school physics led me to try out a bridge rectifier with a DC horn. A rectifier turns AC into DC.

I bought a KBPC35-04, made up some wires with spade connectors, and fitted it with a generic motorcycle 12V DC horn. Here's what it looks like:



And guess what? IT WORKS! Now I have a half-decent horn sound, whatever my engine speed. Clever huh? :)

I think I'm going to try a 6v DC horn with it too - apparently running a 6v horn on a 12v system gives you some extra welly.


Update: The MOT inspector didn't seem to like my horn - he thought it was too quiet at higher revs. I can hardly tell the difference.

Cabling and wiring

I have no photos of this phase. I did take some but the card for my digi camera gave up the ghost so they are lost. No problem, as there really isn't much to see. I pretty much followed the routing guides in Sticky's Lambretta manual, and I used strong and long cable ties to mock it all up, then checked everything was working (start up, test lights, brakes etc.) before fitting the aluminium ties.

I did make a rather annoying mistake when fitting the bodywork back on though. I stretched the throttle cable out of place with the legshields, and when I discovered this rather than remove the legshields again (which were a pain to fit as they are a bit mis-shapen in some places) I had to fiddle with the cable in situ beneath the bike.

Fitting the hydraulic disc brake

Fitting the hub was fairly self-explanatory, and the one problem I did have (front wheel not being central in the forks) I posted about previously, and I rectified it by straightening out some wear on one of the fork links. It is worth noting however that these hubs (mine's a SPAQ/Sterling jobby) don't require a nut between the link and the large plate on the right hand side. The hubs don't come with them, but at a recent parts fair I saw some of these hubs with nuts fitted - I guess the stall owner thought they were missing and fitted them!

Here's a pic of the assembly in place:



To connect it all I discarded the rather bulky rubber hose that came with the unit and bought a new slimmer Goodridge braided stainless steel one from http://www.busters-accessories.co.uk/. This is what I got:

Buildaline Adaptor Banjo 90deg 3/8 Jic Male 5.99 1 5.99
Buildaline Adaptor Banjo 45deg 3/8 Jic Male 5.99 1 5.99
S/B Buildaline Hose 1100mm Clear


The 90 degree banjo enabled me to avoid having any exposed hose at the top of the bike. I simply used a round file to create a hole in the top if the headset for the banjo and the small front brake wire to feed through. Here's the end result, a lot neater than any others I've seen:



And here's an internal shot, showing how it all worked out:


Here you can also just see a replacement white earth wire that I fitted from the headlight to the mounting point of the throttle guide. This provides a more reliable earth than the headlight rim as is standard. The loom comes in on the right on my bike, as I simply couldn't find the room on the left!

Wednesday 3 June 2009

Get your motor running

I may not be able to ride out on the highway yet, but getting my motor running is a major milestone and somewhat of a relief. I've jumped the backlog of blog posts about cabling, wiring and plumbing in the brakes to report that the beast is alive.

I expected a whole heap of electrical or fuel/air niggles to resolve, but there were no such problems. Instead there was a mechanical problem that was entirely my fault. When I first tried to start it the resistance on the kick pedal felt wrong, and further inspection revealed that the flywheel was actually contacting something behind. I removed the flywheel and uncovered two potentially disastrous problems. Firstly, I used a spring washer on the stator bolts, and the top one that holds the cable support was slightly too prominent and had come into contact with the rear of the flywheel. Needless to say I replaced the washer with a wavy one. Secondly, and rather embarrassingly, there was a wavy washer lodged between two magnets on the flywheel:



I've no ideas where it came from, and I'm finding it hard to believe the washer was there when I fitted the flywheel as I would have checked it. Perhaps it was sitting loose in the mag housing or around the stator and got picked up after I fitted it?

Anyway, here's the video taken by my wife on a mobile phone in the late evening so it's a bit dull. It isn't the first start, as she'd have been standing there for over an hour; It's the second. I'm also pleased to report the noise didn't wake the baby.