Sunday, 23 December 2012

The saga of the knackered enfield...

I've got a very nice Royal enfield Crusader sports on the go:

It's a 1960 version, this being the model before the legendary continental GT. It's a much better bike to live with though, the continentals were known for an over-tuned engine, a fragile 5 speed gearbox (remember that bit!), a dissolve and split prone fibreglass tank...but a flyscreen and miles of chequered tape, so not all bad. This is the 4 speed, slightly tuned, steel tanked version.
Anyway, it's not actually mine. A chap at work has had it in his shed for 8 years, and was unsure whether to sell or sort it. Apparently he bought it as an unfinished project, the engine was rebuilt just the electrics to go. Since I'm broke I offered to look at it. Perfect plan-a free project! Originally it was going to be a recommision (oil, timings etc) and a rewire to 12v, negative earth, generally nob on electrics...
First indication of something wrong was the timing. It should be set at 5 degrees static, which goes to 30 degrees full advance. Some clown had set it to full advance...easy fix though. Here is my timing disc mount, it's tapped to fit on the end of the crank. Make a pointer from some welding wire and off you go.

You can also see how rough the stator is, made some pretty sparks when I got it briefly running!

Once I moved on to the gearbox, things started looking dodgy. First I struggled to find any gears, after a strip I was pleased to find a full set of cogs and teeth. The plunger wasn't looking too clever though, someone seems to have tightened it right up against the quadrant plate. Again, fixed OK.
So, I reassembled it, to find 3 good gears and a reluctant top. It engaged OK, but dropped straight out. Remember that fragile 5 speed gearbox on the GT? In a typical british lash up, RE came up with a 5 speed gear cluster the fitted in the 4 speed space, by thinning all the gears down. These thin gears were notorious for shedding teeth, to the point that enfield gave you a free 4 speed cluster with every bike. Quality! One mainshaft gear in both boxes is the same size and number of teeth, but if you put the thinner 5 speed one in your 4 speed, it doesn't engage top gear.

5 speed on the left, approx 17mm thick overall. 4 speed right, 23mm ish thick

This picture shows the engagement, note the huge gaps on the drive dogs. Judging by the wear in the dogs, someone put that in then rode round holding it in gear with the gear lever. Note the shiny pin through the selector fork. The original had worn almost halfway through, had the wear filled with braze then filed dodecahedral by Stevie Wonders engineering co.
Other horrors include this stud. If you look closely, you'll see the thread is waisted, BSF at each end and almost BSW in the middle.

As you may suspect, some threads needed helicoils. Here's a tip for drilling aluminium for them. Get a drill chuck, use that to hold the bit and turn it carefully by hand. You're less likely to snatch/do damage, and more likely to get it central. If you fancy making new studs, you could perhaps make them all BSW too.
So, having got an idea of costs, I ordered all the bits:

That's for the owner, I love the point in a project when all the new bits arrive.

So, tonight I've been trying to make the clutch go on without rubbing the screws behind it. Talking of which, here's where the gearbox sprocket goes:

To get to it you need to strip the clutch, which needs a special tool. Also, that big screw at a funny angle is plugging an oilway to stop it leaking while the cover is off. Reason 23562 why we don't make these any more.
Whilst fiddling with the clutch, I discovered a missing spacer on the crank sprocket:

It slides quite freely, and could easily move enough to chuck the primary drive chain off. Whoever rebuilt this, please chop your hands off so you can't do it again!

Finally, hitchcocks have a handy guide to stripping the engine here
Here is some extra information you may need:

Use 20/50w oil in engine, gearbox and primary drive
If you think your 15 tooth mainshaft gear is wrong, the 4 speed is around 23mm thick overall and the 5 speed around 17mm.
If you skim the back clutch plate as per instructions, remember to skim the back face too. There isn't much clearance between it and the screws holding the sprocket cover on.

Wednesday, 9 May 2012

Finishing the KH250

I'd not touched the KH for about 3 months, when I got a text off Dave (who sold it to me, and still has another). Are you coming to the North West rally in Blackpool, 25th-27th may? Naturally I said yes, then remembered my triple was in bits in the front room...
Luckily, a load of overtime pay was imminent so I had a good look round the bike and ordered what I needed. I also gt round to sending back some incorrect seals to Simon at, only 4 months since I first said i would :S Stafford show got me a pair of Avon roadriders £20 cheaper than on ebay, as well as a nice Mikuni oval bore carb for the bantam. That was a good buy, made an adaptor and above half throttle it goes like a stabbed rat. Unfortunately it's far too rich below, so more attention needed there

Anyway, back to the KH250. Parcels of bits arrived, and I rapidly remembered one reason why I'd got a bit fed up of it-polishing up stainless steel bolts is really boring, but once you do a few it looks a bit half arsed if you don't do as many as you can. Even odd bolts, like the one with an eccentric tang to take up slack in the front brake lever:

I also made various little spacers, such as for the shock absorber top nuts (where I'd removed the grab rail) and the headlamp (fitted to generic cheapo brackets)

I've just finished a bank holiday of triple attacking, and it now only needs the carbs rejetting before MOT. Though the battery appears to have died over winter, so might need that doing first. Managed to get it added to my 400/4 insurance policy, which was a lot cheaper than having its own.

                                                                  Work in progress

Getting the electrics to work was a real nightmare, at one point it went fro working perfectly to the main beam warning light coming on instead of the instrument lights. A good dose of electrical cleaner and a wire soldering up sorted that, so far it seems OK.
The last real nuisance was a chaingaurd. I managed to get one off some chinese two wheeled horror at Clarks (local bike fettlers), after some cutting up I produced this:

So thats it-pretty much ready for the road, since 1991. I was still in nappies in 1991.

Saturday, 14 April 2012

Toy train progress

I recently bought a copy of Martin Evans/LBSCs book on how to make a model 9F, which made me realise I should probably finish Tich first! This design has a very sad point of interest-LBSC died before he finished it, so Martin Evans took it over. If you've not seen my previous entry on LBSC, look him up- his writings are a great read even if you skip the loco making bits.
Anyway, back to Tich. In a moment. First, I've started rebuilding the bottom end of my shed. This will be my machine shop, locked up and insulated from the rest of the shed to keep my equipment nice and get my micrometers out my bedroom. The old wooden pile came down in a day with the help of Nathan the CBR125 breaker, and it was burned 2 weeks later in a pretty awesome party. Between the two, I reckon I dug 5 tons of soil out.

The brown hairy rug decided to be my foreman throughout, ensuring I'd thrown enough balls and all bags of soil were properly peed on. They'll take him on at work next week.

Anyway, having got that out the way I started on Tich's smokebox, or if Andy's reading "the bit where the face goes". To make it I had a bit of brass tube, a casting for the front, one for the door and one for the saddle, which it sits in. The front was easy enough, first I turned to a hammer-in fit in the tube. I then did that, and mounted the lot in the chuck to machine the front and the radius edge. Here's a handy tip for anyone holding large, thin wall tube in a 3 jaw chuck: make a spider by drilling and tapping every other edge of a nut, then fitting bolts to suit. Put it in the tube like so, with the bolts nipped by hand so it sticks in squarely:

You can then tighten up with the bolts exactly under the jaws, avoiding either bending the tube or having it do an alien face-hugger impression when you start the lathe up.
I made it this way as I wanted to avoid a great big lip on the front of the smokebox, where the tube sits proud of the casting. A quick google the next day showed that I shouldn't have, they all look like that-but I'm making it, and I think it looks half-arsed. Now I've said that I've got to make everything perfect :S
The convex door shape required a new technique. LBSC recommends using both slides to create the shape as best as possible, which is doable. Instead, I made a tool a bit like a wood turning tool out of a blunt file-grind some clearance and a good, flat edge on the end. I then clamped any old tool in the toolpost, to act as a rest, and cut the door freehand, pretty much how wood turners would. Make sure the rest is very close to the job, have an emergency stop close to hand and dial 99 on your phone just in case.

The smokebox saddle needed facing off flat on the milling machine, which is a shame as I don't have one. However, another common trick is to use the lathe. In this case I made a fly cutter from a big lump of steel that was lying about, and a small bit of square HSS. For those who don't know, a fly cutter has one cutting edge offset from the centre. You can use it to face off big things, though nowadays you can get some pretty huge indexible insert cutters that are far better. And pricier.
Here is said cutter in action. I used such a chunky bit of metal in the hope it would be nice and rigid, which gives better cutting. What I didn't account for is the carriage lock on the lathe being pretty knackered, so it just pushed that back instead-spent all evening taking about 1mm off. Still, one more thing learnt...

Wednesday, 21 March 2012

Mystery sidecar chassis

A while back, a mate of mine got a sidecar chassis for a Z650 project. He mentioned there was another, bigger chassis on the same scrapheap, so naturally it turned up in my yard today. Can anyone identify what it might be? As you can see, it is about as long as the BMW, and very solid. I'll restore it, then either find a suitable cheap hack to glue it to or sell it.

As these two pictures show, the inner rail is bent slightly. I don't think it is meant to do that, hopefully it'll come out OK.
Edit: Just found a number stamped into the rear RH lug-B8 2008

Saturday, 25 February 2012

New lathe

I could have sworn I'd posted about my impulse buy of a mystery lathe, but apparently not. About a month ago, I spotted said lathe on ebay. It was only ten miles away, so I had a look, and bid. It does make sort-of sense: it is three phase, and unknown, so not as much interest, plus it was close enough to take a look. The next weekend I roped in a few mates and my hobbling Dad (silly bugger fell off his bike, turns out he broke his leg :( he's OK apart from that though.) to go and fetch it. This was my usual organisational shambles, we wound up an hour late, Dad got lost and the chap in whose shed it was got a bit cross. Luckily his son (the seller) turned up, so we did a rapid demolition job to get it in the trailer, and buggered off quick!
So I've spent some of the last month stripping and cleaning most of it. Plan is to store it in big, cleaned and repaired chunks until the bottom shed is rebuilt to house it. Overall, it doesn't seem bad for what I paid. A model engineers forum ID'd it as a Denham Junior Mk2, and produced a photocopied manual-a rare luxury for me.

Sadly, it hasn't been too well looked after. The feed gearbox was devoid of oil, with some pretty worn teeth-still useable, but it'll rattle. It was also full of swarf, after the genius designers decided to leave a huge gap right under the chuck. I'll be using a lot of silicone sealant to prevent that.

The apron had lots of oil holes for the various bearings, all of which were full of grease, swarf and that rather sickly shade of green someone got a bit carried away with. I put grease nipples on, mostly to keep the crap out.

Other than that, most of it was a straighforward clean up. It is quite incredible how much grime and swarf can get where it shouldn't, I'd recommend anyone buying a second hand machine to do this. I'm not bothering with a repaint, it'll add weeks onto an already long job and won't do anything for the worn bits. Here is the swarf that was under the headstock, in the bed casting:

But talking of paint-if you must slap some on your old lathe, please either do a full strip or don't bother. It gets in all manner of places, gumming things up and only looks like you're trying to tart up a shonky old pile of scrap.
One upgrade I do want is coolant. My IXL has been much easier to use after aquiring a botle of dormer tapping fluid, but using it on turning won't do my lungs any good. The Denham already has a chip tray, so I'll fit a drain and a splashback and (hopefully), job done.
For the drain, I had a good idea, Hopefully it is an actual good idea, and not the sort that ends in disaster either. Using a sink plug kit I bought in error ages ago, I can fit a bottle waste trap, as found under sinks to catch bits of food/murder victims etc. In this instance, it will catch any swarf that gets past the mesh.
Now, if I fitted the plug hole thingy as per a sink, it would be proud of the tray and I'd have 1/8" of coolant always there. Since the one I had was steel, I welded it underneath:

In my minds eye, I imagined a perfect bead of weld both on the putside of the flange and round the inside of the hole. In reality, I'm shit at welding so I stuck a load of silicone round the inside and prayed to Myfordius, the roman god of machining. Wish me luck!

Monday, 2 January 2012

What I did in my christmas holiday...

...mostly sleep actually!
When I wasn't asleep, I was being excited over the parcel that turned up from Motad before christmas. Stainless cb400/4 downpipes, take 2. After much fiddling and swearing, they do in fact fit. Hooray!

...except the stub out the collector box is bigger than standard...bugger! The silencer is a lovely growly dunstall knock-off I got given when the original quite literally exploded. They rot from the inside, meaning often you'll see a pipe that is literally held together with the chrome plating. Then when someone tells you about making the bike backfire with the killswitch, it blows a sodding great hole out. Anyway, quick bit of surgery with a hacksaw and some hammers has it fitting. Only problem is it needs a little weld, and I have no welder. Yet.
Having proved it fits, I took it off again to polish it. You can't tell in that pic up there, but it had quite a rough, emery cloth finish-I'd told Motad to only do it rough to save money. Would have been cheaper and easier to get them to polish it I suspect, but oh well. I'm also spraying those manky fins and collets in heatproof black, after a dose of shotblaster. I'll give the engine a bit of a clean if and when it stops raining, should look lovely for the new year.
Below is the difference between polished and as they came:

The KH250 hasn't been ignored, but progress there is all small boring bits so no pics. Got some rather fetching braided lines from Hel, in purple :D Even better, I got some funky stickers...
Finally, I have yet another project running parallel. Not a bike this time, it actually has 4 wheels!
A 3 1/2" gauge Tich, a live steam toy train. Always wanted one or two of these big models, and a few years ago I got the drawings, frames and a few castings for this beginners design. Then last year I got a second, which was much more complete. That is what you see here. So far I've just cleaned and assembled what was there, to see what needs doing. As far as actually making bits for it...see the shiny silver bit on the front? The first bit I've made, and it took bloody hours! Only 3 more to do...:S
If you're feeling bored, the designer of this is worth looking up. His pen name was LBSC, real name Lillian "Curly" Lawrence. He wrote loads of articles for model engineer, and designed well over 50 model steam engines in various sizes and complexities. He was also very intolerant of criticism, and eccentric even for people who make toy trains. When I get round to my time machine I'd love to pop back to the early 60's and go for a pint with him.