500 miles so far and it just gets better!

 

This from an article I've sent to the Vincent Club Magazine: -

 

In practice

So how did I get on? First it was obvious that the ATD had to go, which is a benefit in itself. Possible options include locking it with locking wire or welding the ears up. Don Alexander was adamant that neither of these is acceptable. Forces in the ATD are greater than anyone thinks. It had to go so I made up a drive unit as described above.

Therefore the exhaust system and the timing cover had to come off. Got new gaskets for the cover and the exhaust ports. Removed my ATD and magneto and the bottom mounting stud, carefully cleaned the mounting area of the crankcase, fitted the ‘O’ring to the new unit and inserted the screw, with a good washer, into the bottom mounting hole. I applied the special driver and offered up the unit. In my case it only just fitted in one position. The slotted holes allowed for this. Mine was OK, I hope yours will be. I certainly can’t move the mag round a bit to fine-tune the timing, which is the usual reason for such slots.

I set the magneto to the reference position, indicated by a punch mark on the drive shaft, locked it with the rod, which fitted through a hole in the body and another in the shaft inside, and set the engine to the 35 degrees full advance position I intended using. I tightened the ET54 nut, but not too much. Just like it says in the instruction sheet. Setting the timing is that easy; once in position nothing can move while it is being tightened up. I refitted the timing cover with a new gasket and a smear of grease and refitted the exhaust system.

The coils are best mounted below the mag body and in front of the oil filter housing plug. The steel strip provided had to be bent and otherwise distressed to achieve this. There is room under a Series ‘C’ cover but I had to adjust the run of the breather pipe a bit and do a bit of fiddling to get the cover on snugly.

I made sure everything necessary had been refitted and tightened properly and I was ready for an engine run. I took it for a 12 mile run to warm the engine up and then checked for oil leaks &c. All was well, so now I can get some serious miles in.

After one hundred and fifty miles.

I checked the installation for security and oil leaks. No problems. An accurate check of the timing indicated a figure of 35 degrees, which is what I thought I’d set it to. This should be ideal for unleaded petrol. The Tufnol wheel shows no sign of distress.

Riding impressions in the first 350 miles. (It took that long to write this bit)

I’m at a bit of a loss what to say here. Any impression has to be subjective and I can’t compare mine with any other Vincent. I can compare it with how me ol’ ’Arley used to go and with several manual-magneto bikes. What I can say is that my Vincent has been developed over the last ten years or so to be quite reasonable as regards starting and general running. With the new magneto the low speed flexibility now compares very well with these other bikes.

It used to be very, er . . . edgy, twitchy, sensitive, uneven, jerky – I don’t know the words to quite describe it, but now it is as easy, soft, smooth and flexible at low speeds as any bike I’ve ever ridden. In other words the retard is now working far better than it did with an ATD. Even a new one.

Acceleration through the gears also seems to be greatly enhanced with no signs of knocking or pinking except when deliberately badly overloaded. And not much even then which suggests that the advance curve is better suited to the engine. My ATDs have never behaved as well as this.

Starting is instant at all times and idling is of the “B’dum, B’dum” variety as never before but I think idling that slow is probably far too slow. Maybe I’m kidding myself but overall it feels so much sweeter to ride at all speeds than it ever has before, even with a magneto known to be a good one. And I am impressed.

I had a look at your new technical page, which is interesting, but I would be grateful for a more technical description of the system that would bear comparison with, say, those in the 'Haynes' Techbook. Leaving out anything of a commercially sensitive nature, of course.¹

Is it possible to obtain a spare coil 'just in case'? Or is it just pointless? (Ha!)²

I can't imagine why anyone should want to keep their Lucas ATD when your advance/retard works so well.³

I fixed my coils on the third hole after bending the steel strip to get them in the right position.

I thought the slots were for fine adjustment. Mine won't move and I suspect that the cause is that Vincent Series B and C crankcases were sand castings and varied a little more than the die-cast Series D ones like Don's.  If I intended to race, I would look a little more closely into this, but at the moment I'm quite satisfied with the improvement I've got.

Anyway, thanks for an excellent instrument. I'll keep you posted.

Regards,

Eddie Saxton