Thursday 7 July 2022

Turbo TR1 - more cowbell!

Let's kick it off with another mod to the Everyday TR1 (aka Tractor) - I found out that either the old Turbo had a longer footbrake lever than stock TR1 or what is more likely as the original Everyday TR1 had been crashed before I bought it, had a shorter one. We're only talking maybe 15-20mm, but as always with levers and mechanics, every bit helps.

But back to the star of the show - the Turbo. One thing I didn't check after awaking the old girl so rudely, was whether the alternator would actually charge the battery. 

As a matter of fact it does, but only on two of three windings. (Which answers the question, where the good stator in the Tractor came from...) In other words, as long as the lights are not turned on it will have *just* enough juice to charge the battery. Good enough for what I have in mind, if I am honest. Also with most of the lighting converted to LED it was good enough on the Tractor for several years.

On the other hand, I realised that without a fuel pump the float chamber on my BS40ies is a bit on the small side. So even though it performed rather nicely, on a longer pull the float chamber would run dry.

Grab a bit of stainless exhaust tubing and some engine silicone...

... and bring out the big boy. (Mikuni VM44)

It doesn't look too big in the picture, right? You may want to see it in proportion to the turbo (or the cylinders):

And what can I say, if you don't run the float bowl dry, a lot more interesting things happen when playing around with forced induction. I will soon take up the project again and see what can be done, so far I've reached the point where boost is easily going into the 5PSI region and you can start to feel how it actually gets quicker the more boost is applied, so...

Wednesday 6 July 2022

The Everyday TR1 - KTM Duke 790 rear shock

If you go through the various Yamaha XV-related forums, FBook-groups, etc. you will see the same five or six models of rear shocks being recommended. Very few people actually dare to try out something completely different or even worse: something new. 

Well, I happened to more or less fall over a 2018 KTM Duke 790 shock, which had done less than 10,000kms from new. In KTM circles this shock is not quite regarded to be quite the cream of the cake, but this also meant it would be rather cheap. Also, what are the odds for it to be worse than a shock from a mid 1980ies dirtbike?

The shock measures 390mm from eye to eye, which is 25mm longer than a TR1 stock rear shock, but exactly the same length as my previous XT600 Tenere rear shock and it's got another trick up its sleeve: both mounting bushes are of 12mm inner diameter, making it a straight fit.

Now if you were a cheeky bastard, you could ignore the fact that the swingarm has got a 45mm cutout...

... yet the shock is only 24mm wide.

And quite frankly, aside from the lower shock pin being sprayed with water and a rather theoretical chance of the shock twisting a bit and thus getting bent over the years, I'd say totally doable. 

But we're not after doing a fix in some emergency situation. So two spacers approx. 25mm OD, 12mm ID and 10mm wide where quickly made on the lathe from some leftover ally scrap. 

Et voilá: Rear shock properly located inside the swingarm.

At the same time, I had one of those: You really know you had a bike for a while, when you have to replace the horns, because they have stopped working due to bad weather motorcycling, i.e. at least partially rusted to buggery.

Verdict after the first test-ride? Well, suspension technology made some notable leaps forward in the last thirty years. It's a bit stiffer than the old XT shock and it should be brilliant when riding two-up. That being said, I may actually end up reducing the pre-load a notch or two. Shame the 890 has got an external reservoir, which makes it impossible to fit into the TR1 frame.