Hmmm interesting one this. Lets just take a step back and think about basics. I've always thought it best to keep any weight as low as poss on a trials bike. As for oil isnt it usually a goal to apply a cooling effect to the oil if possible?
Taking both these into consideration then i think i would come down in favor of an alloy oil tank in the conventional position.
I'm sure others will put the arguement for under the tank but it does put the weight higher and the fuel tank shrouds the oil tank plus the oil tank is also directly over a hot engine Hmmmm as i said interesting one? Which way are you leaning?
It sort of depends on what you are doing with the rest of the bike. I made a Top Tube Oil Tank 'very similar' to a Sammy Miller one. However I made mine from slightly larger diam tube to increase the capacity. I also added an external oil filter (
Oil Tank under the petrol tank, or, in the conventional place on the right hand side of bike, one better or one worse anybody have any feelings, for or against.
I personaly i think the best part of the Pre65 trial is the Crosscountry, it is just pure majic, it's all how you read the terrain, and experience, it can also be demoralising, and funny, that when you think you are flying accross the bogs on your cub and feeling great only to be passed by the likes of Mick wilk on his little James and wonder how the hell does he go so fast.
Pressures sound about right but why did you choose Pirelli ? terrible tyres for trials IMHO. Personally would always use Michelin front and IRC rear at the pressures you state. With Pirellis you could probably let all the air out and still get less grip than decent tyres at road pressures. Good luck.
Hi everyone, I am confused by the process of adapting modern internals into a pre-65 type fork leg. I am an engineer by trade, but find it hard to visualise the process. Is anyone out there able to explain the concept?
Do you bore out the classic fork bottom? That would weaken it.
Do you make special bushes? That would be difficult, as modern fork stanchions tend to be of larger diameter than classic.
Do you machine the outside of the modern leg, and somehow fit the entire modern fork within the classic fork bottom?
I can only imagine that classic fork legs must be chosen carefully, with larger diameter ones preferable, or modern forks chosen that are close to the diameter of classic ones. Clues anyone?
Dalesman used initially Austrian Puch M125 motors, switching to German built Sachs 6 speed 125 motors around 1971/72, I think.
The bikes themselves were built in Otley, Yorkshire and there was a thread about them on this website not that long ago.
They are rare in that not many were built or used for competition after 1973/74. I think Competition Developments headed by the late Alec Wright bought over the remnants of Dalesman which was founded by Peter Edmondston, father of Fast Eddy (Paul Edmonston).
I believe that there may have been an American financial backer at one time. Bill Brooker left Greeves Motorcycles and worked as Competitions manager at Dalesman for a couple of years too.
Joel Robert had input in the initial development of the moto-cross bike which used a slightly different frame to the trails version.
The front forks of the 1969 bike used UK made REH (Robin E Humphries) forks, yolks, front hub and brake plate, whereas the rear hub is a Puch Cush drive type from the M125S road bike (Sears handled Puch in the USA). The tank was aluminium alloy made in the UK, similar to the Wassell bike built around 1971/72.
The MX bikes' air box was a glassfibre item made to suit the frame dimensions. The frame was manufactured by Jim Lee, who was the one time sponsor of road racer Mick Grant.
1935 Triumph 2/5 trials
in Pre-65 Bikes
Posted
Try this site
http://www.tomcc.org/
Vinnie