Hi, how do you lot do it? Havent got the time to ride it unless I do a trial. Any advice?

Cheers

Looks like you'll be running it in at a trial then

Any reason not to? It's a old twinshock, Normaly run it 40:1 would i need more oil for first tank?

I would leave oil ratio as it is. Lower the carb needle clip a notch or two to make it run a bit rich for the first 2 hours, then avoid high revs or over 3/4 throttle for next 6 hours and it should be fine

run it until warmed up each night and let fully cool

I would just use it normally,dont thrash it up long climbs or long periods of wide throttle openings.keep the oil mix the same,if you add more oil you run a weaker fuel mix and risk overheating.

Starting and then stopping an engine after a short time will accelerate wear,better to run it for a good amount of time - ie,a trial. I built my TY250 motor back in 2006,its done a lot of work since then and still runs as well as it did back then - just don't cane it too hard...

the rings need to go through heat cycles from short warm ups before proper use

The heat generated by new rings rubbing against a newly finished cast iron bore is way more than the heat generated by riding the bike in normal trials operation. Because of this, on an air-cooled bike, the cylinder and rings can easily get hotter than the oil can stand, should the bike be ridden continuously on the first run. I find that on the initial run following a rebore, the cylinder fins can go over 100 degrees C within 60 seconds of a cold start, even with no load on the motor. Each successive engine run sees the temperature rise rate reducing and after about 6 runs of the motor going from stone cold to operating temperature, the bike can then usually be ridden gently continuously.

A liquid cooled motor with electroplated bore is completely different because the heat generated by the fresh rings is probably less, and the heat can be removed from the rings and cylinder bore surface much more quickly.

You should use mineral oil to help run in the rings to the bore . Synthetic oils are to slippery and dont allow the rings to seat in or take any high spots off . Run your normale oil ratio or drop it slightly But do 3 heat cycles run up the bike let it get hot switch off a low to cool and repeat . Ride it but do not labor the engine or rev it hard for too long . Ride it for 20 minutes around a field with no hills so it's not laboring . Switch off and alow it to cool then ride it again and go abit faster id suggest after doing this 3 times strip down the barrel and inspect how the bore looks for even wear all way round . One other thing you must check the rING gaps in the bore as well normale you should have a 0.02 mm to 0.05mm ring gap . And remember cast iron blocks heat up slower than the aluminium piston so antill it looks like every thing is worn in nicely id say it's readdy for normale ridding .

You should use mineral oil to help run in the rings to the bore . Synthetic oils are to slippery and dont allow the rings to seat in or take any high spots off . Run your normale oil ratio or drop it slightly But do 3 heat cycles run up the bike let it get hot switch off a low to cool and repeat . Ride it but do not labor the engine or rev it hard for too long . Ride it for 20 minutes around a field with no hills so it's not laboring . Switch off and alow it to cool then ride it again and go abit faster id suggest after doing this 3 times strip down the barrel and inspect how the bore looks for even wear all way round . One other thing you must check the rING gaps in the bore as well normale you should have a 0.02 mm to 0.05mm ring gap . And remember cast iron blocks heat up slower than them aluminium piston so antill it looks like every thing is worn in nicely id say it's readdy for normale ridding .

I think you meant .2mm to .5mm