Monday 12 March 2012

Lets do electrics.... maybe

I had planned to "Do the electrics" this weekend just gone.  How naive can a man be?
You don't just 'DO the electrics'.  You have to DO (at the same time) the switch brackets, the grommet selection, the engine fitting, the cable routing etc etc etc.   Its all a bit 'the-knee-bone-is-connected-to-the-thigh-bone-the-thigh-bone-is-connected-to-the...etc etc"

To make things even more difficult for myself;   1) I don't have an original loom to work from, 2) I don't have original handle bar switches, 3) I want to fit indicator lights.  And so I am inventing my own wiring diagram and loom

Within an hour of springing out of bed and boldly declaring that I was "going to DO the electrics today",  I was back at the vice making brackets to hold the rubber strips in place,  so I could fit the leg-shield,  so I could calculate the cable runs......

Sorting out the electrics is going to be a longer job than I'd anticipated!

The rubber side strips that get sandwiched between the leg-shield and the chassis are held in place with 6 metal clips.  Mine original ones were rusted beyond re-use, and so I made some new ones out of mild steel sheet.  Ideally I should have had them zinc-plated, but I can tell you now - even with the best will in the world, I suspect my metal brackets wont rust away in the time I get to ride this bike! (and besides Waxoyl is the wonder rust-preventer).


And then there was the bracket for the after-market footbrake switch that needed to be made and fitted.

The more astute Manurhin geek might notice my foolish mistake in this picture (I hope there is only one!)  When making up my new rubber mounting strips, I had assumed (I should never assume) that there was 2 transverse rubber strips.  One at the front, and one at the rear.  The fact that there wasn't a rear one on the bike when I stripped it didn't seem to register with me, and it wasn't until I was trying (and failing) to bolt the body-cowl hinge-plate down that I realised that there isn't supposed to be a rear rubber strip! Doh!

Sometimes only a large hammer can solve a problem

I've started to assemble body parts to the chassis.  Its all rather exciting..... and at the same time, terribly disappointing and frustrating.  Nothing seems to fit as I imagine it should!
I've never seen, let alone worked on, another Manurhin so I have no idea as to how well this bike was put together in the first place.  And on top of that I've had to source parts from various far-flung places that may or may not have been designed to fit together anyway.  And so there is a fair amount of 'fitting and fettling' that needs to be done in the assembly process.  Despite everything being powder-coated... (yes yes, I can hear the 'proper' engineers among us muttering that I should have done a 'body-in-white' assembly before powder-coating - lets not go over that again) ....it's amazing how much flex there is in the coating while gently persuading a panel to ease its shape over your knee.

However there comes a time when you realise that no matter how hard you try (or how hard your knee is) there is no way you are going to humanly reshape some bits.  My steering bump-stop being a case in point.
It wasn't until I had assembled the front forks onto the frame with the forks cowling that I realised that there was more turn to the right than there was to the left.  I measured it several times and started to wonder if there might have been some old and peculiar French motoring law designed to encourage motorcyclists to turn right more sharply (perhaps to get them off the main road quicker?)  But on closer inspection I discovered (and I really should have seen this before) that the flange bracing the frame and headstock - which also acts as the stamping for the frame number AND the steering bump-stop, was bent out of line!

How on earth could this have happened?  That is quite a hefty bit of metal to be bent so.  Surely if this had occurred as a result of an accident or some rough misuse, then wouldn't the forks / handlebars / wheel / frame also show signs of stress? I cant see any!

I had acknowledged the fact that a risk of painting too early might be having to damage paint later during fitting - now was the time to take a deep breath and accept it.  With the forks removed, armed with a 4lb club hammer and a hefty dolly, I whacked seven-bells out the flange and encouraged it back into a central position.  Paint damage was minimal, the turn equalised and I went to bed that night wishing once again that my bike could talk and tell me its story

Monday 5 March 2012

rubber bits

There are a number of rubber bits on this bike; predominantly chassis, body, seat mountings (and an internal mud-flap) - and mine are all a bit tatty, so I decided to replace them with new.

As seems to be normal around here lately, the industrial rubber suppliers I used to know of (15 years ago) are either no longer in existence or gone all too-big-for-a-trade-counter.  But it wasn't long before Google linked me through to Central Rubber & Gaskets Ltd.  John at central rubber was great.  He had exactly what I needed and he cut it to size too (And he can diecut gaskets to order too.... which could be very useful to know about in future)







And while we are on the subject of Rubber, we have an interesting conversation going on at the moment on the Manurhin Scooter Interest Group member site.  The rear suspension on the Manurhin and DKW Hobby is nothing more than compression of a couple of 65mm diameter rubber blocks.  Mine appear to be in good condition..... but how would I know if they were as good as they were on the day they they were made?  How would anyone know if they had the same cushioning properties today as they had when they were designed?  Does rubber age-harden?
I'm looking forward to taking my scooter for a ride to see just how these rubber perform.  But if I don't like the ride quality..... What can I do about it?

Sunday 4 March 2012

Getting there!


All coming together.... almost

Its time to start assembling things.  All the parts are painted after-all so presumably its now just a case of bolting it all together right?  Well, almost.
Over the past few months I've been scouring the web for all the bits that were missing from my bike, and  I've been excited (and lucky?) to discover them from all sorts of places and sellers.  I have quite a large box now of 'parts'.  It all feels a bit Johnny Cash


However, now as I start to put bits together, Im discovering that things are not all as simple as I had hoped.  For instance;

From 4 different sources;

  • one wheel,
  • one set of forks,
  • one speedo cable,
  • one speedo drive
...... and guess what?  It doesn't all quite fit!

I'm not sure if its the speedo cable that is too short or if I've got the wrong style of speedo drive?





And then at the other end;




I've had not one, but two good-as-new spare rear brake cables in my parts box for months now, and a replacement rear wheel ready to go, but its only been this weekend when I've tried to marry them together..... and guess what?  it doesn't quite fit!

I have the old cable from my bike as a pattern so I can confirm that the lengths of my new cables are correct, and so are the ends, and I even thought the adjuster end was the same until, i went to screw it into the brake back plate.  It would appear that the thread on my new adjusters are finer than the thread on my original adjuster and the back plate - unfortunately the cables have soldered/crimped ends so I cant simply disassemble and swap the adjusters





So what have I learnt?  well, nothing really.  I've known for ages now that DKW and Manurhin clearly didn't have a master collaboration plan!  They were either extremely relaxed in their standards offices, or fabulously creative on the shop floor.  Either way, we can never assume that any part is compatible with another.