Basket Cases

[David Lahey]

We are currently in the incredibly priveliged position of being able to run trials while most of the population of Australia is in some form of lock-down for COVID 19.
Here are photos of most of the twinshocks in a trial at Benaraby last Sunday. The photographer is Nicole Casey who also rode the event.
Cedric van Heerden is riding one of Tony Bax's P65 bikes in the photo. I couldn't find a photo of him on either of the TY175s he also rode.
The orange and white TY175 rider is Ross Hamilton. The blue TY175 rider is Peter Smith. I'm on my KT250.

[David Lahey]

So the COVID border closures have changed the first-ever Australian Classic Trials Championships into the "Australian Border Separated (BS) Classic Championships". Excellent name.
I will be sorely missing riding with the people who would otherwise have come up to Queensland to ride.
I still hope to ride (COVID situation pending) and have been grooming and primping and fiddling with my KT250 relentlessly with the goal of enjoying a ride at this event in a few weeks time.
The bike has generally gone great in local trials up here on the last three weekends but each time when it got fully warmed up the idle speed increased. Today I did a couple of things to try and stop that happening. One thing was to improve the fuel flow to the carby. I found it seemed to have less trouble when the tank was 1/2 full than 1/4 full so today I replaced the fuel filter and hose. The filter was very old.
At the same time I fitted a gasket in the carby top where there had been none. I'm thinking that maybe air could have been leaking in there. I've had one 10 minute test ride this morning and the idle was stable but I want to get it really hot later on today for a better test.
I'm also still fiddling with the clutch. Today I'm planning to fit new EBC friction plates to see if I can run even lower pressure plate force.

[David Lahey]

The stack height is only 0.15mm different in total to what came out so I'm going to try the EBC plates without changing the setup of the springs.
The only thing I'm concerned about is the amount of metal in the EBC plates friction material in that it might cause accelerated wear to the aluminium surfaces at each end of the stack. Looks like the standard plates have no metal.
The plates that came out are genuine plates that I fitted many years ago.

[David Lahey]

Well the EBC plates are fantastic in the KT250.
The action is terrific - controllable slip, strong engagement, no drag and instant release

[Greg Harding]

Hi Everyone,

So the COVID border closures have changed the first-ever Australian Classic Trials Championships into the "Australian Border Separated (BS) Classic Championships". Excellent name.

There it is again "COVID"! This word has been popping up a bit lately. What does it mean and does it affect me? Should I be worried?

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[David Lahey]

A while ago I posted about how I wanted to try out increasing the trail dimension on my KT250. Well a few things lined up today:

There was no trial to ride or set sections for.
It was too rainy to go for a motorbike ride (80mm at my shed).
It was an RDO.
My wife was at work.
My panel-beating muscles needed a break from working on the TL125 tank.

Today a spare KT250 top triple clamp got a lot of attention. The first thing was to bore the axle hole bigger and at a slightly different angle and face the ends at 90 degrees to the hole. I'm posting the photo to prove to a friend that it did fit in my tiny lathe, mounted to a face-plate. What I'm doing here by moving the axle hole rearwards is to move the top ends of the fork tubes forwards slightly to move the front axle back slightly.

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The next thing was to make an eccentric bush. For this I finally got to use a vintage four jaw chuck. This job was my excuse for buying the chuck. I almost stuffed this bit up though because I thought that one turn on my dial indicator was one mm when it was actually one tenth of an inch. Sorry I forgot to take a photo of the bush being machined but you can see the eccentric bush sitting in place in this photo.

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Next was fixing a stripped-out handlebar clamp thread. This was my first ever go at using one of these thread-serts to fix a stripped female thread. I can see why they are popular, being much more robust than a heli-coil repair. After I did this photo, I ground back the top edge of the threadsert with a Dremel so it doesn't touch the handlebars.

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[David Lahey]

Well I've had shed time again this weekend and the KT250 is back together with the increased trail as shown above.
I went for a test ride between showers of rain and am very happy with the result.
I'm sure Chippy and JC2 will be keen to have a try when the opportunity arises.

[JC1]

Good job Dave,
Clever man

Yes, I'd love to try it but won't be up there till next winter probably

How much did you reduce axle offset

[David Lahey]

Good job Dave,
Clever man

Yes, I'd love to try it but won't be up there till next winter probably

How much did you reduce axle offset

In theory, 2 mm at the top end of the fork tubes should give about 6 mm perpendicular to the line of the fork tubes at the axle.
Measurement using a tape measure parallel with the floor, the axle moved back 5 mm.

[tat ty]

So ... As a total ignoramus on frame geometry ... And in complete awe of the amount of effort and precision you guys achieve ... I need to ask the question.

What noticeable advantage in handling would you expect that 5mm to deliver?

Alastair.