Now that I've had it on the road a few days, I'd only been riding it gently to bed everything in and I'm unsure how much I trust my mechanical skills, what bolts had I forgotten?
I took it to a faster stretch of road where I could hopefully wind it out and see just what it can do, 30... 32....33....33 still.... engine starts to bog I pull in the clutch just as the rear wheel locks up. Yeah soft seize baby. I had been checking the spark plug religiously every trip (2miles max) but had never gone over 30mph, the plug was brown and lovely each time, as the engine was cooling I checked the spark plug to find it was white which I presume is because I had the throttle open much further and the bike was now running on the main jet whilst also creating more mechanical vacuum internally. I waited about 15 minutes and started it up again, works just as it did before, fine at low speeds.
I took it back to my garage, took off the engine covers and found where my issues were. Oil/petrol leaking out means air can get in causing lean conditions at high RPM right?
So the tear down began. Yup soft seize alright.
Luckily for me the grooves in the cylinder can't be felt only seen so it can be used again, I'll still be as careful as possible.
I decide that there's only one way to fully sort my issues and that's to split the engine case apart and put in complete new seals and gaskets.
You can see here the evidence of dirt getting in past the crank oil seal which is also where the oil/petrol was getting out behind the flywheel.
This is where I am today, waiting for new parts to arrive. Whilst I'm in there I'll do the cruciform just so it has no reason to pop out of gear anytime soon as well. My jets are 102, be3, 140 which are exactly what other people use for this setup and carb has no leaks because the top of the engine is bone dry, fuel delivery is good as I have a SIP fast flow tap with a reasonably short pipe from the tank to the carb I also checked that my tank breather holes weren't clogged creating a vacuum issue for fuel to leave the tank quickly. I'm going to replace the carb gasket too anyway just to be safe, though I'm sure that's not the issue.
All in the name of having a retro mode of transport eh, looks good in the sun from 10 ft though. We'll get there.
I took it to a faster stretch of road where I could hopefully wind it out and see just what it can do, 30... 32....33....33 still.... engine starts to bog I pull in the clutch just as the rear wheel locks up. Yeah soft seize baby. I had been checking the spark plug religiously every trip (2miles max) but had never gone over 30mph, the plug was brown and lovely each time, as the engine was cooling I checked the spark plug to find it was white which I presume is because I had the throttle open much further and the bike was now running on the main jet whilst also creating more mechanical vacuum internally. I waited about 15 minutes and started it up again, works just as it did before, fine at low speeds.
I took it back to my garage, took off the engine covers and found where my issues were. Oil/petrol leaking out means air can get in causing lean conditions at high RPM right?
So the tear down began. Yup soft seize alright.
Luckily for me the grooves in the cylinder can't be felt only seen so it can be used again, I'll still be as careful as possible.
I decide that there's only one way to fully sort my issues and that's to split the engine case apart and put in complete new seals and gaskets.
You can see here the evidence of dirt getting in past the crank oil seal which is also where the oil/petrol was getting out behind the flywheel.
This is where I am today, waiting for new parts to arrive. Whilst I'm in there I'll do the cruciform just so it has no reason to pop out of gear anytime soon as well. My jets are 102, be3, 140 which are exactly what other people use for this setup and carb has no leaks because the top of the engine is bone dry, fuel delivery is good as I have a SIP fast flow tap with a reasonably short pipe from the tank to the carb I also checked that my tank breather holes weren't clogged creating a vacuum issue for fuel to leave the tank quickly. I'm going to replace the carb gasket too anyway just to be safe, though I'm sure that's not the issue.
All in the name of having a retro mode of transport eh, looks good in the sun from 10 ft though. We'll get there.