Saturday, 28 March 2015
-JdK- Juergen in Germany has these wheels available. The rear wheel is an Enfield, the front wheel is a Horton. These wheels are correct for c1929 Nortons like the Models 16H and 18. Juergen is asking €700.- for the pair but would also consider swapping against 500cc JAP OHV parts. Contact us for Juergens email address.
Thursday, 26 March 2015
-JdK- One of the most annoying nuts on a Carroll OHC engine must be the nut holding the bevel on the camshaft. I may be 'teaching grandmother to suck eggs' but it took me two weeks to tighten this nut so here's the story.
The best way to assemble a Carroll cambox may be to first fit the bevel to the camshaft and tighten this nut. Then the camshaft can pushed through the bearing in the cambox, and spacer, cams and roller bearing fitted whereafter the nut on the other side of the camshaft can be tightened. The problem is that this is a left-hand nut. The camshaft is locked with a spanner using the nut at the bevel side but as this one is a right-hand nut, when one nut is tightened the other nut may come loose and vice-versa.
So the nut holding the bevel should be very tight. The 'square' at the end of the camshaft is easily damaged and cannot be used; further, the camshafts are made from unhardened steel like EN8 and can be easily twisted and damaged when you apply brute force.
The best way seems to be to just grip the bevel between two pieces of wood (shaped like in the photo above) in a vice. This looks brutal but the teeth on the bevel will be embedded in the wood and the torque will be spread over a large part of the bevel. It won't damage the bevel.
When doing this I found out the bevel needs to be gripped very tight in the vice otherwise the wood will splinter. I used good quality Meranti hardwood and a one-meter length of steel pipe to tighten up the vice. This was required because the nut needed 200 Nm torque (that is a lot!) before it was tight enough to allow the left-hand nut at the other side of the shaft to be torqued to 50 Nm. This is probably because the nut at the bevel side hardly moves once torqued up to around 40 Nm. It needs a really good pull with a very long spanner before it moves after that!
(Ian Bennett and Dr George also use this method and around 200 Nm to tighten this nut. Others suggest to just fit the cambox the engine, lock the crank and then tighten the nuts on the camshaft; that means putting a lot of torque on the teeth of the bevels. Perhaps the engine may withstand such abuse but it doesn't feel right to me.)
Sunday, 22 March 2015
-JdK- Malte recently sold his 1939 Model CS1; an interesting machine as it has seen little modification since it left the factory. In Malthe's own words: "This bike has not been restored. Most details are as when it left the factory. All numbers match. The only new parts are new (old stock) Dunlop rims fitted in the 1970's. It has had three owners from new and all are related (two friends and 1 son-in-law). I partly dismantled the machine years ago to give it a thorough cleaning. 99.9% of the nuts and bolts are still the original dull plated and undamaged items. When you then add the original cloth cables and electric wiring which is very, very brittle, very brittle rubbers for the tank fitment, original levers, original ammeter, clips holding the wire to the rear mudguard, dull chrome petrol and oil pipes (which were almost black from oil and petrol, before I cleaned them up) etc. etc it suggests to me that this bike has not seen much, if any modifications.
-Richard- This one indeed looks very original. It does have a left hand (nearside) front brake plate; also notice that the speedo drive gearbox is in the wrong place. The brake will still work O.K. but it will put undue stress on the fork leg as the correct plate puts the pressure vertically up the fork tubes. This plate will put a horizontal force on the fork tubes. Perhaps it was replaced when the original one got lost and a right hand brake plate could not be found?
Malte does point out that the 1939 Norton parts catalog actually lists this brake plate (part number 3650) as fitted as correct for the CS1; see the copies from the catalogue below! We suggest the catalogue is outdated and that any wheel with a right hand brake should have a 3651 right hand brake plate or similar; like the Models 30 and 40.
Another small feature is the chromium dome on the front of the primary chain-case. This chaincase is chromium plated all over and then painted black only to leave the dome and edge plated. We understand from the records that the machine was delivered with a chromium plated chaincase so this should be the original item. It's a very minor and confusing detail but black chaincases with a chrome plated dome (thus no chrome underneath the black paint) were a feature for one season (1945/6 ) only.
Tuesday, 17 March 2015
-Richard- Some photo's to identify Norton girders. The pictures of the forks in-situ (above) are 1946 Model 16H type. The main points are the four headlamp lugs (Inters never had these) and the off-side brake anchor. The four small headlamp lugs were only used on the post war girders. I have seen a couple of Inters fitted with (modified versions of) these forks in recent years.
|Inter', left; 16H/ES2 etc right|
The other photo's show the forks from my 1939 Model 30 Inter' (left) alongside a set of blades from circa 1933 16H/ES2 type for comparison (on the right) as these are the same dimensions as the 1946 ones. All Norton girders have the same dimension across the top spindle but the difference at the bottom spindle is half an inch wider on the splayed 1946 type which has the interchangeable wheels.
Also notice the brake plate anchor which is oval on the Inter' instead of round and the position of the cable fitting lug which is separate and much higher than the standard forks. These features were used from 1936 to '39.
Splayed girders from a Model 16H etc. can be modified to resemble Inter forks. There are three levels of craftsmanship to do this:
- Cut the bottom forging of the blades and remove material and then braze back together and line ream the forging and also reduce the width of the headstock bottom yolk all of which is best done by someone with the relevant skills.
- Heat the fork tubes below the bottom forging and bend the tubes to a suitable pre made jig, bit of a bodge but it would work.
- Bend the tubes cold and hope no one notices (AARGHH !!)
Sunday, 15 March 2015
Wednesday, 11 March 2015
Thursday, 5 March 2015
Friday, 27 February 2015
-Stephen- Above a couple of photos on the last project that my father Julian and myself had been working on together. Being a totally brand new SOHC engine with a works type cam box with enclosed rockers; and yes, you do see alloy rockers (the originals being steel).
The valve stem ends do not enter the cam box but pushers (or tappets) are used. We have copied the cambox as per the one I managed to get hold of and I am under the impression that only 6 of these camboxes were ever produced, plus an initial first off which looks a little different. The first off never had enough room for the valve lift used by the works racers and is in Germany somewhere. I may have to modify the set up for the operation of the valves and increase the diameter of the pushers just like on the DOHC camboxes. My copy is also slightly different to the original in that it will fit standard crankcases. With the original cambox the top bevel sits 1/16" further out so if you find an original you will have to modify you crankcases to use the cam box.
-JdK- Have a look at this entry and this entry for more info on these camboxes
Monday, 23 February 2015
-JdK- Karl-Olof in Sweden sent these pics of his c1929 Model 16H Norton he wishes to sell. The description below is in his own words. Offers invited! Contact us when you are interested.
"This Norton was assembled using parts from several bikes. The engine has a Model 16H crankcase and uses a Model 1 cylinder and crankshaft; it has a new bigend and good W7 cams. The Lucas magdyno has been rebuilt. Carburetter is an Amal 6/011. Front fork was rebuilt using new spindles and bushes. Magneto cover, chain covers, rear stand, mudguards and carrier are replica's. Exhaust pipe, silencer, toolbox and speedo cable/gear are not included. Offers invited"