Having closed the timing cover I found that the engine is too tight...something obviously binding .

 

 

 

 

 

Bush on timing side inlet camshaft clearly is still too close to shaft as it is shining bright.

 

Checking gap

 

checking matching gap on engine side of timing covering.

 

I have this spare timing cover but I note the bush in it is also shining bright showing rubbing.

 

Lowering height of cylinder as an experimental alternative to a longer conrod -required due to lower piston compression height.

Not easy when the task is just on the border of the capacity of my lathe. Low speed is the answer though.

 

 

 

Always seems a shame to have to strip everything apart at the end of the season but I am putting in a different engine so everything within the cradle must come out. I have tried doing it by leaving the gearbox in and raising the engine but it is more trouble than it is worth.

 

Having recently bought an old oil pump  found it to be seized through not used. This is very common as the main body is made from Mazak- the British trade name for Zamak. It is an alloy which shrinks with extended age. This feature is fine if used regularly as it takes up wear on the pump wheels but leads to seizure if left idle.

It was used due to being cheap and very easily die cast- being zinc based- for jobs like this. The only solution I have found is to dismantle the pump with great care - heat the body so that it is too hot to hold ( it is cold in the photo!) and use circlip pliers and much metal polish such as Brasso to free each impeller wheel round and then when each is done do it for the assembled pump.

 

Now that the season is over and work can start on the bike I decided to build a new engine with a lighter flywheel after having much thought over the pros and cons of flywheel weight. There is much in the way of arguments for ' heavy' as the momentum gives explosive acceleration due to the kinetic energy stored in the flywheels when the lights turn green.

 

However I am experimenting with a badly corroded set of flywheels so they would have needed dressing anyway. I loath turning cast iron as it comes off as crumbly dust which gets everywhere. I have heard of people trying a magnet at the tool to try and collect it but I just brush it down.

Woke at 0400 hrs to find that on Sunday morning the 12th Oct that at there was heavy fog. Set off anyway in the dark icy fog heading for the last event of the season at York- over 5 hrs much of it in the fog.

 Was hopeful that engine problems were now rectified. Saw the sunrise on the A66 heading for Scotch Corner and the start of the run down the east coast to York.

Got there to find that the fog was even thicker at the track. Waited until lunchtime but showed no sign of clearing. Headed back for long drive and found the fog had cleared on the M1 but too late to turn back; plus I had no way of knowing if it was still bad in York.

An unhappy end to the season.

Driving though glorious Yorkshire on Sunday morning I saw many of the yellow painted bikes as a tribute to the Tour de France...unfortunately the weather was not as kind for the York raceway sprint meeting I attended. It was wet. The great  organisers as is common practice let the cars have much of the early time when it looked like it might dry up.... this delay for bikers meant we did not have much time for spanner work if things were needing it.

 

 

When things did go wrong and the old girl refused to pick up revs...... I found the primary chain was so tight you could play a tune on it...no time left...off home for a 5 hours drive.

 

You can see the wet here. I don't mean me.

 

 

...these pics are Richard  Cravens wonderfully developed Vincent / Norton....I took at York. Quite a character...but don't be fooled...he still shows  the young guns the way.

 

 

 

 

 

 

Always a good idea to try positioning new bare flywheels with a length of wooden broom handle in place of mainshaft to check all is approximately as calculated. Not least the available distance between them for the conrod !

 

A crack in the originals can be clearly seen close up running towards the mainshaft from the oil feed outlet on the inner wall . Probably would not get much worse if only subjected to light road use but sprinting is too much of a risk.

 

Norton simply used cast iron for their road going OHV singles so it is to be expected that after a half century of use this might be weak spot to reveal itself.

 

Found a use for old CD or DVD discs. Download a timing disc from the internet and glue it on. Although in theory the bigger the diameter the more accurate the reading I find that it is more easy to mark zero for TDC without making up a bit of stiff wire and finding a place to attach it.

 

The original Norton piston looks more to do with the steam age than modern items. I have invested in a Wiseco forged piston which looks a more serious a component. It was designed for a Triumph and the difference is obvious being the pin size and the compression height; being the distance from the top face and the centre of the pin. I can handle these issues however with a new bush and a longer conrod. The valve pockets are however a little high and  must deal with this .

 

 

 

The beauty of a modern high performance piston is beguiling.

 The standard of machining is space age. 

A work of art.

 

The tappet follower which was designed (right) after the Norton factory decided to move away from having a lever type tappet was good for several years from the post-war era until they had a minor re-design for the alternator models. It is not difficult to see why the design had a much more substantial thickness as any attempt to remove the thinner item would break the casting....as the factory must have discovered themselves.

 

When Pierre Vernier invented the vernier scale he must have known he was onto a good thing. As I belong to the generation of people who used slide-rules before calculators came along the idea is very familiar. However just as slide rules were referred to a 'guessing sticks' so vernier callipers were called " very- near" callipers. The big change was when they became digital and I now use it constantly.

 

Hired a VW transporter van for the trip to York raceway. As I drive a VW car the controls were intuitive . I would have liked a cruise control however !

 

 

The Norton fitted perfectly and VW have ideally placed securing points for the web fastenings.

 

 

 

My estimate for the loading height proved spot on and the ramp I made up worked a treat- simply a length of steel channel with two lengths of mild steel angle  bolted at an angle to provide the transfer from slope to horizontal. The angle of the slope made for an easy loading by myself.

 

York raceway is fairly easy to find and is on the old wartime RAF Melbourne runway.

 

 

 

Plenty of room to park up but I was a little later than some having probably travelled much further than the average competitor. Sadly a bad misfire proved incurable after a few attempts to sort so headed back up the M1 homewards to take the ignition apart and find the fault which seemed to arrive when the engine was hot. 

 

 

 

Yorkshire was sunny and warm compared with the journey down which was wet and foggy.

 

The actual sprint strip is well laid out and well run with a good length of run off and a country ride along a perimeter road back to the pit area.

season starting

 

Got machine out of garage first time this year.

Seems ages since I sat on the old bike since it has been on the trailer.

 

Not happy with plate holding competition number plate; must modify it soon. 

Had wonderful visit this morning to the Scottish Motorcycle Show in Edinburgh. Spent some time speaking with the " Yorkshire ferret" -AKA Shaun and Ben Waters- do visit the great website .

http://yorkshireferret.blogspot.co.uk/

Bob McIntyre in Joe Pott's workshop in Bellshill. The" Joe Pott's Garage" display at the show is a homage to this time- and is shown around the country apparently- is a must for enthusiasts of this period and the activities in Bellshill especially. It is a fantastic achievement to behold -what I had thought had disappeared- racing hardware faithfully re-engineered. A very fitting tribute to the " boys" who kept the British flag flying and I cannot even imagine anyone else doing it all so professionally .

Certainly worthy of a much wider audience. Congratulations to Shaun and Ben Waters.

The finished bike was on display by the quite remarkable chaps of the Yorkshire ferret team.

Their painstaking efforts and keenness for fine engineering, detailing and employing the highest standards are as much a reflection of their reverence to Bob McIntyre/Joe Potts  and their team as the bikes themselves.

 

 

A blueprint of a standard Manx Norton engine

 

 

The great man, Bob McIntyre  working on a Manx Norton .

 

 

http://members.chello.nl/~wgj.jansen/

Wonderful website on desmodromic valve gear. The 1957 design by Hopwood and Hele to try and keep Norton's competitive was an impressive effort by a British factory.I wonder why they did not work with Joe Potts on a joint effort.