Sunday 30 August 2020

The XV SingleCarb manifold

To this day a year ago, I promised a friend to make a single-carb manifold for him. When he said "no pressure", I am not entirely sure, he was planning to be this patient about it.

The show stopper last time were the wrong-radius bends I was supplied... and then life and a workshop move got in the way. As can be seen in the picture, the radius is substantially smaller on my new bends.

So lets start with a fresh set of bends:

The more or less finished product. It's equal length and -radius and should allow both cylinders to get close to the same amount of air/fuel into each one. 

I'll finish up the welding next week as I simply ran out of time today. Also I have a few more ideas on how to design a few variants of this manifold for turbo- or supercharger use and take it from there.

Tuesday 25 August 2020

Everyday TR1 - improving front brakes

Lately I did some work in order to get the rear drum brake to work as it should. The front brakes are actually working very well with the right pads, but... they squeal a bit.

In general these calipers are meant to slide freely along the center holding pin, once this one gets a bit sticky, the caliper will not align perfectly* perpendicular with the brake disk anymore.

As suspected the slider is sticky and the silicone paste that was on there has vanished. (Been washed out.)

After quite some scrubbing with a brass brush removed most of the caked on residue, yet still the surface felt somewhat rough.

Therefore the next step was to attack the slider bushing with a small polishing disk and polish it to an almost mirror finish. 

Then reassemble the whole lot and lo-and-behold the brakes feel more crispy. Especially the point where you can feel that they start to bite is more precise. The squealing? Well, it improved...

Saturday 15 August 2020

Dre-XT-Stueck - the re-Dre-XT-Stueck-ening (pt.2)

Didn't get much done on the old XT as I was mostly fixing up my new (to me) car.  That being said, I can at least show the frame off in its new paint.

Still plenty that needs to be done as both exhaust mounts are either missing the threaded boss or missing entirely. So that'll keep me entertained once the engine is done and back in, so I can line the whole exhaust up again.

Monday 10 August 2020

Dre-XT-Stueck - the re-Dre-XT-Stueck-ening (pt.1)

Now the Dre-XT-Stueck is awesome - we can all agree on that. What we shouldn't agree on is that the piston and head are still fine. So in order to improve the awesomeness... let's fix the frame first. As the Dre-XT-Stueck grew some extra CCs and the fact that it is easier to use a different frame and re-register the bike than to have the displacement altered in the existing paperwork, I got a frame, which needed some love and got started with it.

First thing to tackle: The coil mount. Pictured is the one on the current frame.

Luckily I had some leftover brackets from the GPZ500 coils, where I lobed off the tabs.

And then welded on. Using the coil to get the spacing right.

Bit of dressing up of the tabs and then see if a proper broomstick could be pressed into service as a makeshift frame holder.

Works just fine. Next up some cutting to get rid of the sidestand switch as my XT frame (and loom for the same reason) came without a sidestand switch, it had to be removed from the new frame as well. 

And some non-standard holes on the rear subframe needed to be addressed.

This is only primer, but honestly it looks mighty fine in white too. (But the frame will be covered in flat black.)

The one thing I realised, I forgot to fix was the mounting point for the muffler, as the nut that usually goes in there has been drilled out and the whole mount needs reconstruction as this was done in a rather drastic way...

Sunday 2 August 2020

New motor and new tools for the Rhino/Coronet lathe

There was nothing essentially wrong with the old motor on my lathe, except it was only 750W and 1500rpm. Which exactly mirrored the stock 3-phase that was originally on it. But with modern tooling constantly demanding higher speeds and higher chip-loads, it was time for a bit of... more oomph and more speed.

For some reason the 3-phase motor that was on there, was mounted with this spacer plate, so I took the liberty of using it as a drill-jig.

And here we go: 2.2kW (or 3hp for you non-metric types) of 2800rpm, single-phase goodness. And I really have to work out how to wire in a reversing switch, as that will make screwcutting a lot less tedious.

The second part of the story is the thing with tooling. Normally you would expect people to step up their game from CCMT to TCMT tooling. I went the other way. The former Matra with its geared head, had a better power-factor, which allowed me to run TCMT tooling and get decent finish on my parts. With this lathe being belt driven that's simply not gonna happen. So after some consultation with my local lathe tool rep (and cross-checking with some catalogues), I settled for some CCMT09 tooling, which with its smaller tip-radius decreases the load. In combination with the higher spindle speed, this nets mirror-finish results (at last).

With VCMT-tooling I still have some vibration issues, which I (by now) tracked down to a slightly loose motor and a belt that's a bit jumpy. 

Once I have fully sorted the vibration issues, I have some very, very high expectations for the finish quality that I can achieve with this lathe. I suppose some rubber machine-feet and a new (slightly longer) belt are in the cards to tackle this issue.