Trials Australia Forums

eagle wrote:I can't believe how far the front sprocket is from the swingarm pivot point.

Yes, crazy. There's always lots of quirks in old motor designs. This motor design started out in the early 1960s.
I think and are worse than for quirks though.
The sprocket location doesn't cause issues on the models with 4" rear end travel like this one but the late model Pursangs and Fronteras required elaborate chain guiding.

The side stand finally lives! Much more convenient now.



Some original 1970s Betor shocks. They came on an but I think they are the same as what came on Alpinas. I rebuilt these ones many years ago.



The brake pedal stop was very worn (it rests against the swingarm pivot tube). It now has an adjustable return stop. I haven't got a pedal return spring for it yet.

With this fibreglass model 85 tank, I was planning to leave the original finish because it has great patina and is the original graphics done by the manufacturer.
So today when I was cleaning the old glue off where the round badge goes on, I got quite a surprise when blue paint appeared on the cotton bud I was using to clean with. I was using thinners on the cotton bud which I knew would be pretty safe on fibreglass but paint??? So it turns out the fibreglass has a blue gelcoat finish with silver and blue paint over it. The blue paint is a slightly lighter colour than the blue gelcoat.
I got out another very original-looking model 85/97/99 tank and found it also had blue gelcoat with lighter blue and silver paint over the blue gelcoat.
I wonder why they did the graphics this way?
Anyway here's a photo showing where I have removed the blue paint in the centre of where the badge sits.

I replaced a few inches of the original stand that had been damaged from being pushed hard against the up and down stops. The photo showing the damaged section was taken after I straightened it and painted it, but then decided it looked too horrible to leave like that.



What was such a surprise was finding how thick the tubing wall was when I cut it. It's 3 mm thick! which is quite thick tubing for that OD.



I'm pretty sure the stand on the model 85 Alpina is the same stand fitted to the early Sherpa T models (the models with the stand mount on the frame) so there would have been quite a weight saving from taking the stand off for competition.

Hi Everyone,

David Lahey wrote:

eagle wrote:I can't believe how far the front sprocket is from the swingarm pivot point.

Yes, crazy. There's always lots of quirks in old motor designs. This motor design started out in the early 1960s.
I think and are worse than :Bultaco: for quirks though.
The sprocket location doesn't cause issues on the :Bultaco: models with 4" rear end travel like this one but the late model Pursangs and Fronteras required elaborate chain guiding.

Ah the old faux pas, it has always amazed me and it would have been so easy to rectify by simply fitting the output (front sprocket) on the rear gearbox shaft. That would have been a more conventional distance from the swingarm pivot and allowed for more wheel travel.
OK so you are probably thinking Wouldn't that make 5 reverse gears?

Yes but won't a run backwards? Obviously 2 wrongs don't make a right but 2 reverses does make a forward.

OK so you are probably now thinking What about the kickstart going the wrong way?

That would have been a great time to fit the kickstart on the right (Correct) side!

Here are photos of my latest acquisition, a real Trials bike:

Good to see you replaced those sprocket bolts with originals David. I would of hassled you for years if you didn`t!!!!! Greg that is NOT A REAL TRIALS BIKE. It`s even worse than an imitation one.

Thanks Graham. You are a motivating influence for the better appearance of my s.

Even if it isn't a , Greg, that is a great find. Amazingly complete!

As for the gearbox faux pas, I'm expecting that there was a good reason at the time and I'm going to try and work out what it was.

My first thought is that the people hated so much that they did it that way to be as different as possible to the design of the time!

Much more thinking required - and a great topic for discussion

One of my kids reckoned it looked pretty sad without the tank badges and she was right.
I reckon it looks slightly less sad now

David, nice front guard, is it a Goneli with that stupid mud flap removed?
I have a pet hate for Goneli front mudguards with that easily removed flap that people don't remove.

Rod wrote:David, nice front guard, is it a Goneli with that stupid mud flap removed?
I have a pet hate for Goneli front mudguards with that easily removed flap that people don't remove.

It's one of these Stilmotor guards Rod, but in grey, square both ends.

https://www.inmotiontrials.com/product/ ... ard-white/

I originally bought that grey front Stilmotor guard for my model 49 because I wanted to use a rear Stilmotor in grey on it and they came in pairs front/rear.

It has been an excellent front guard on the model 49 and after stealing it for this model 85 I'm still deciding what front guard to replace it with on the model 49 . Maybe another one? Not sure yet. There's a new front guard mount going on the model 49

I know what you mean about the mudflap on the front Gonelli looking out of place on some bikes. I have a few bikes with the front Gonelli with that flap cut off and fitted with the round end at the front end which I think looks OK.