Member postings for Hopper

Nice work. The quick action lever on the quadrant clamp has upgraded your Super 7 to match the Drummond M-Type!

Dougie, if you want to build an old JAP engine, a plethora of original factory blueprints is available for free download here LINK

Site says further drawings available from the VVMC. Apparently someone found a microfilm of all the old drawings after the factory closed down.

There are guys building their own full sized replicas and classic racing them so might be some web postings on their efforts somewhere.

Edited By Hopper on 24/01/2023 21:07:51

But don't the Hondas have separate intake and exhaust lobes, on one camshaft?

Beautiful model engine there. And shows perfectly how the single lobe cam works. Looks like by having the cam followers contacting the cam below the centre line you get less than 180 degrees of cam rotation between when the inlet valve is fully open and when the exhaust valve is fully open. So you could vary the cam timing by raising or lowering the pivot points of the bell crank cam followers. The same effect as varying the lobe separation angle on a normal multi-lobe cam.

Edited By Hopper on 24/01/2023 11:17:08

Interesting. It has the Super 7 cross and top slides so quite likely is a very late model ML7R. So basically a Super 7 minus the power cross feed and clutch. Looks pretty nice. And the price has jumped up 50 Quid since you mentioned it!

Edited By Hopper on 24/01/2023 10:59:23

And it would have been full of glass tubes or "valves" and taken up a room of your house.

Except every other British gearbox I remember working on has the end cover full of the same oil that the rest of the gearbox swims in, in fact you usually fill the gearbox up with oil through a hole in the end cover. Bit unique having the end cover devoid of oil. Certainly Nortons are full of oil there, and from memory BSA and Triumphs and Ariels. But twas a long time ago for the latter three. Very thoughtful of the Enfield chaps to provide a little oil hole to make up for it though!

I welded mine together out of a couple of pieces of 1" thick steel plate stacked on top of each other.

With strange bell crank cam followers that pivoted above the camshaft, one running on each side of the cam lobe. Some (earlier) models had two lobes, others (later I think) had just one lobe. Famously Sammy Miller's trials bike GOV had the single lobe cam.

Edited By Hopper on 24/01/2023 09:52:00

Edited By Hopper on 24/01/2023 09:52:15

Edited By Hopper on 24/01/2023 09:53:46

Edit, that last post should read "and NOT the main gear selector like most".

I think the big saving in a washing machine is no reduction and reversing gearbox needed to get the back and forth agitator motion. The motor just drives direct and reverses direction at the required intervals. Must save a lot of manufacturing costs on the old gearbox types, which also gave a lot of mechanical problems as they got older.

It seems quite likely that VFDs will become the norm in the future, as fractional horsepower three phase motors are already cheaper to buy than the single phase ones, due probably to the large numbers of three phase used in industry so mass market equals lower prices. And like all electronics, the inverter/controller units will continue to come down in price as production numbers rise. So eventually single phase motors might die a quiet death as they become relatively more expensive ..

I travelled a lot on steam trains still in daily use when I backpacked around India in about 1980. Lovely to see and hear. But with all the carriage windows open in the Indian heat, everything inside was covered in black gritty coal ash. Pretty messy and not all that romantic. But it was a great way to travel.

I mostly went second class where you had a seat reserved in an alcove with half a dozen other passenger so always plenty of good company and some very interesting conversations. And the food was just amazing. You ordered it at one station, and a station or two later, an Indian curry feast was delivered to you from the station cookhouse. It was a moveable dinner party for sure.

Third class was a total melee. No reserved seating and they sold as many tickets as they could. So you had to fight for a seat, or even room to stand, and spend the journey jammed in unable to hardly move. And there seemed to be a less than endearing custom. Each little alcove had a small fan like a desk fan with wire guard around it, suspended from the ceiling. The preferred place for those sitting on the upper luggage rack to put their sweaty sandals to cool off was right on top of the wire guard around the fan, thus blowing fragrant sandal fumes over the passengers below. Unforgettable!

That's certainly a unique set up. But I guess the end cover holds only the neutral selector and the main gear selector ratchet mechanism like most, so no need for it to be filled with oil. Very thorough to provide a little oil hole for the shaft where it passes through, and a little screw to blank it off. Gotta love old British motorbikes. They all had their very own ways of doing things. I have had my eye out for an Indian Bullet 500 for a while so maybe one day I will get to learn about these esoteric Enfieldisms first hand. Great old bikes.

Plus one on that. I quite often do the same, having a no-grinding, no-torches policy inside the shed full of leaky old motorbikes. But it is often just more pleasant to hacksaw and file quietly rather than fire up angle grinder and belt sanders and the like. And for you, central heating of the most central type!

I think having the tightening knob and the taper as two separate pieces would held too. The knob would screw onto the shaft and push upon the taper piece which would be held captive in the female taper by the knob. You might get away without having to split the taper that way. This would allow you to undo the knob without it being jammed up by the stuck taper and once the knob is loosened off, pressure is off the taper and so it should then let go. Should!

Ah, but the MD of course is not "no one". He is the MD. That's different.

Yes obviously a posed pic. Advertising rarely has anything to do with reality. But the unrestrained hair would be the only thing I would worry about.

Don't know about UK law but here high vis is not required in workplaces like small machine shops where there is no truck traffic etc. or overhead cranes that might drop a load on a slumbering employee camouflaged in blue twill.

But it still does not tell you what the oil hole/screw is for. I checked my old Royal Enfield service manual and it says all Enfields have a gearbox oil level screw that you take out and fill the gearbox until oil comes out that hole. It says location of the oil hole varies from model to model between front, back and middle of that end cover. So unless you have another level screw there somewhere, that is most probably what it is. Pretty standard thing on old Brit gearboxes. I know Norton, AMC and BSA boxes had them. But never tinkered with Enfields.

Your workshop manual should give you the procedure for changing gearbox oil which should mention it.

It looks a bit similar to the cross feed clutch on a South Bend 9" or one of its clones, Boxford, Hercus etc. so you may be able to copy their set up. AFAIK the Hercus clone just uses a cast iron knob with taper like you have made in brass. Perhaps cast iron or even steel is a bit less "grippy" than brass? Other South Bends seem to have a pair of split tapered "shoes" that the knob and its threaded shaft expand into the surrounding taper. They appear to be cast iron or maybe steel. And I think they have some kind if spring pushing the tapers apart when the knob is unscrewed.

One of our Boxford owners should be able to tell us what their cross slide clutch cone is made of.

I think they are sensitive to what oil is used in the apron too. Something like ISO32 hydraulic oil would be the norm.

Also, it looks like the female taper in your gear could use a bit of a clean up, although pics often make such things look worse than they really are.

Edited By Hopper on 23/01/2023 05:21:37

Edited By Hopper on 23/01/2023 05:31:56

Edited By Hopper on 23/01/2023 05:37:13

Edited By Hopper on 23/01/2023 05:38:34