Sunday, 20 January 2019

What the chuck ... and servicing the tail-stock on my Rhino-/Coronet-Lathe

During those quiet days between Christmas and New Years Eve, I stumbled over an ad for a 200mm (8") Emco chuck just like mine, allegedly NOS and with both sets of jaws for a price around the same as a new Chinesium one. Originally I tried to convince the seller to simply sell me the outer jaws, but as he wouldn't, I bought the whole set, thinking that I may use the old Emco chuck on the rotary table of the mill and still have the external jaws to swap in, if I don't need 'em on the lathe.

One of the things you only notice, when you have to carry that chuck around: It is epically heavy. A bit of wood was placed over the bed ways to protect them, in case the chuck would fall off. (It didn't the fit of the chuck and backplate is a lovely ever so slight interference fit, which means it needs a bit of gentle *tappy-tap-tap* with a rubber mallet to come of.)


New one installed. You gotta love vintage engineering, the overall dimensions on the backside are the same to within 1/10mm and the chuck sits on just as nicely as the old one.


The last thing I had to address was the quill-lock on the tail-stock. Lately I ran a live center in the tailstock only to find out, that even though the quill would lock nicely, releasing wasn't exactly in the cards.


As it turned out, the sliding bit was well rusty (as so many parts on this lathe) and simply didn't mean to move at all.



The verdict: Even though not strictly necessary, the new Emco-chuck was definitely a nice investment, it will have to have its innards cleaned out and a regrease. And then there's the elephant in the room: I want and have to get the chuck's backplate off to get the spindle(s) out and replace the drive belt, clean out the old grease from the spindle bearings and ideally also replace the seals. And when I am doing that, I'll also address the runout-issue of the primary drivebelt and install a reversing switch for the motor, so I can run the motor in reverse for thread-cutting. And most likely, when I have all those bits of anyway, I'll treat it to a coat of happy engineering grey, because the flaky and faded green disturbs my workshop Feng-Shui. 😜

A shoutout to all Coronet Lathe users: Should any of you have a user-manual or technical data and/or drawings please let me know as they would come in extremely handy

Sunday, 13 January 2019

Swapping petcocks and rerouting fuel lines on the XS-Triple Sidecar

Sometimes you make a modification to a bike to improve on one issue, only to find out that it was some negative side-effects. In this case, fitting these lovely Ducati TT-F1 petcocks with their twin-outlets helped to improve the fuel supply to the middle cylinders, but also meant that I couldn't switch to reserve as the levers would hit the sidecovers. In those two weeks they were installed, I also found out, that the levers themselves are a bit hard to grasp.


The new setup consisted of three T-pieces, creating a horizontal fuel rail, feeding all three carbs and also ensuring that the engine would still run, if there was only fuel left in one side of the tank. 



And that's the old Moto Guzzi petcocks re-installed (not without treating them to a bit of penetrating oil.


... and that's the reality of dealing with modified old bikes as daily rides. Not every job is glamourous, but nevertheless needs to be tackled. With that being said, expect quite a few changes to this bike in the coming months.

Oh and I have a set of TT-F1 petcocks for sale, if you're interested. 

Sunday, 6 January 2019

The Norwegian Job - an engine for Faffi (part 2)

One of the added benefits of this engine is the fact, that I rode the snot out of it in the last decade. Claiming to know its ins and outs might, as such, be a bit of an understatement. To be fair it also worked quite amicably. Pretty much the only thing I've never managed to sort out in the past was the fact that it was very notchy to shift, I measured the endplay of all the shafts about 5 or 6 years ago and given the fact that it is the stock gearbox and everything was set up by the book, I expected to find a bent selector fork. I was looking in the right direction, but it turns out, that in only 37 years old oil and some microscopic scratches had made the selector shaft very sticky.

This meant getting a tool out, most people don't even know, I own.


Top is a very good stock part and below the polished original selector shaft. 



After some oiling of all the gears and a careful testrun of the gearbox (I've had some bad experiences in the past), it was time to clean the other side of the engine cases and then put them back together.


Call me old-fashioned, but I've built all my engines with red RTV and the same German brand has released the same sealant in black last year and yet still, I wouldn't feel comfortable to use it. Also, thin lines of sealant go a long way and are much better than thick gobs. 



Cleaning parts is (I think) nobody's favourite, but polished combustion chambers do have their moments in this respect. From crusty bits to almost done in less than 10 minutes (for both heads). There was still some more to do but, that was literally after going over the head once with a rotating nylon brush.


An interesting find was to be made on the front cylinder. I had heard some detonation, which I suspect was down to a combination of: somewhat optimistic ignition advance, lean mixture and oil/carbon deposits on the piston tops in connection with a very large distance to the squish-area.



As the rear cylinder was fine, I started with a quick hone-job just to give the new rings something to bite into and then checked the ring-endgaps to determine, whether they came gapped correctly from the factory.


Fresh set of rings installed...


... and plenty of oil, probably my only genuine sin, I am guilty of, every single time, when building an engine. But I admit, even after doing more than my fine share, I am afraid of seizures.
 

As the other piston needed some replacement, I had to call in some favours to get a good piston in the right size, so would be a good fit to the cylinder. (Well aware, that normally you do this the other way round...)


Of course at this point the bottom end had more or less been completed, so a few precautionary steps had to be taken, to prevent the clip from falling into the engine. 


The gudgeon pin was dimensionally ok and only needed a bit of a cleanup and polish. 


Looking good again – after taking some measurements on both cylinders, I decided to try my own engine without a base gasket as the clearance is well big enough, yet it would get the piston close enough to the head to make the squish work a lot more efficient. 


And lastly there was the question on the condition of cams and rockers, as they tend to suffer from oil-starvation. In short perfect. The roller cam conversion and the modified union bolt both raise the oil-level and the amount of oil-pumped into the head and in short... perfect.




A bit of moly-grease does wonders as an assembly lube and protects cams and rockers during those first revolutions until the first fresh oil reaches the head. 


And that's where we are now. The engine is basically assembled.



By now (after those pictures were taken) both cams are timed, but the sprocket bolts require a drop of loctite and the clutch cover has to go on and then it's gonna be test-run o'clock in my everyday TR1-chassis, while I do the affore mentioned modifications to my own engine. Also I am somewhat itching to try out a few things with the single left-over piston ...

Monday, 31 December 2018

The Norwegian Job - an engine for Faffi (part 1)

So my mate Faffi fancies a fast TR1 engine, but for one reason or another he can't get his hands on anything decent and I have my old TR1 engine sitting on the shelf. A bit of chit-chat and one thing leads to another and he buys the complete get-out-of-jail-and-enjoy-some-horsepower-package.

Part One is basically the disassembly story and part two will be the reassembly and (test-)installation in my Turbo-TR1-chassis to make sure everything works as it should.

Just to give you an idea: The engine is my trusty old Everyday-TR1 original engine with roughly 110,000km on its back, which was running fine except for a bit of an appetite for oil and a slight knock, which I originally tracked down to the bottom end and some "not-quite-so-slight" oil-leakage from the rear cam-chain-tensioner. (Which was just down to a torn gasket, that I might have missed for a while - it's also very hard to get to, because obviously it was on the rear cylinder.)

Step one was to drain out the oil as good as possible. As you will see by the oily-rags, we didn't exactly a good job on that. We being my dad and myself.


Using the term "cleaned" might be a bit much, but the worst oil and grime has been rubbed off from the top half of the case.


Put the rear cylinder on TDC to make disassembly a bit easier and also to check for camchain wear.


Near perfect - there was some stretch in the camchain, but as I replaced that two years ago (or so) that hasn't stretched any more than the initial stretch.


Even though it should be fairly obvious, I like marking the brackets on the rear cylinder left and right as it avoids a lot of confusion.


No point in denying that this engine enjoyed a sip of oil every now and then I guess. To be fair at this point I dreaded the worst like broken rings or the like, even though the cylinders looked absolutely fine, you could even see a bit of the original crosshatch pattern here and there on the cylinder walls.




The front cylinder looked slightly better, but with that amount of oil-buildup on the piston it came as no surprise that it was knocking a bit, when really, really hot.



With the cylinders pulled from the engine, it was about time to give the rods the casual "pull-test" and nothing really moved. I was planning to do the conrod bearings anyway, but most likely, if this still were my own engine, I'd left the bottom end as is as there was no immediate need to do anything. (One thing I really didn't notice, when pulling apart the engine is that the squish actually worked nicely in pushing the mix away from the cylinder wall as you can see in the clean spots on the side of the pistons.)


I decided to do minimally-invasive surgery this time, which means leaving the crank in the left crankcase. Still this meant fully stripping the right side and at least removing the oil-pump on the left side.

Also in the picture my very first modified 9-disk-clutch. (Still a thing o' beauty, if you ask me!)


Left side, with the shifter mechanism already removed. Contrary to popular believe it is quite doable to remove the oilpump, without removing the rotor, when you undo the single philipps-head bolt that's holding the pump together. 


As can be seen in this very arty out of focus picture. 😇


With clutch and right-hand primary drive removed it's a simple case of removing all the bolts holding the engine together. (Note the three bolts INSIDE the engine, one of which is hidden behind the oil-pump!)


Fast forward quite a few minutes and we have the engine case cracked and the conrods removed from their place. It can actually be done without removing the crank from the cases, even though it is much easier with the crank out. That being said in order to reach the nuts for the rear conrod, you have slide it up and put a bearing cap back in as a spacer, so you don't twist and turn anything.


Now the hard lighting makes the bearing shells look a lot worse than they really are, but there's no doubt they've covered their fair share of miles. Still the crank looked like new and after a short casual glance at the spec-sheet a two-size smaller set of shells (black instead of green for those, who want to know) was selected. 


And that pretty much ends the whole operation for 2018. Conrods have been re-installed and tightened to spec, gearbox is back in after finding NOTHING out of the ordinary, not a single gear suffers from pitting or worn gear dogs and can simply be reinstalled.


So all that's left is to clean up the mating surfaces a bit more, oil the gears and bearings and put the bottom end back together and wait for the sealant to cure. Once that's done the outside of the engine will get a good wash to look representable again. In other words, what does it take to run a (tuned) high-comp, long-stroke TR1 engine for another 110,000km? A set of bearing shells and some fresh rings, because quite honestly, that's the only thing really amiss on this engine. The oil-scrapers have the equivalent amount of tension of a worn out elastic band.

Monday, 24 December 2018

More carbwork - both on the TR1 and the XS-Triple

Theory is when everyone knows how it should work and it doesn’t, practice is when it works and no bugger knows why.

It's time to put some theories to the test. 

In my last post, I went on and on and mentally m*st*rb*t*d on how to jet carbs. Now this didn't all come out of thin air, but stemmed from some minor problems I have with my TR1 flatslides and some rather bigger problems on my XS-Triple sidecar. 

As I outlined, if you run a needle with the wrong (too shallow) taper, you will always encounter a rich or lean situation along the way. In the case of my TR1 it was most prominent the first 1/4 of throttle opening, which I countered by running a slightly bigger pilot jet (#20). This worked fine for obscuring the problem, but meant that when the engine was really hot, it would pop and cut out and also result in some detonation issues, when hot. 

I chose the 6FJ40 needle, because honestly, I knew I wanted it to be richer than the stock 6FJ41 and it was the only one of the needles that I could get some specs for. It might be a bit more than needed, but then again, this is also the needle that's fitted to the two-stroke version of the TM38-carb.


On the top you see the 6FJ41 needle, on the bottom 6FJ41. As the latter looks a lot more like the 6DP01, that I've run in my old VM38-9 roundslides, I think, I might be on the right track though.


The verdict of the jury is still out on this one, but I decreased the size of the pilot to #17.5 straight away and hope for the best. (And no salt on the road.)

The second part I've been playing around with lately were the flatslides on the sidecar. Mainly because I had some serious fuel-supply issues, which manifested in losing idle after a prolonged bit of full-throttle. Personally I think the following pictures don't need a lot of explanation. Except that I now run an incredibly complicated fuel hose setup as each of my new petcocks has got two outlets and I therefore run 4 lines and 4 filters. (It's only a matter of time until something starts leaking, but to be fair, I only have to get some T-pieces and revert to my old petcocks to remedy that.)



See these puny holes? No wonder I could put on my helmet and gloves, while priming the carbs... 


That's more like it.


I tried that out yesterday and guess what, THIS WORKS. Open the petcocks (on dry carbs), wait for a second and then fire 'er up and off you go. Next stop: solve the jetting issues, as she's a bit cold-blooded at the moment, but I think, I have just the needle for that... 

And in this sense: Happy Jewish Zombie carpenter birthday. Merry Christmas. Gud Jul. Frohe Weihnachten. Or whatever you're into on a day like today.