Hi there, it’s summer time, the biking season is at its peak and I’m here writing a new post for the blog, so guest what happened…right, my bike got broken :(. In this post I’d like to tell you what happened and I hope my experience will save you from having a similar problem.
Ok, let’s get started, here is what happened: I spotted that my right cylinder started to produce lots of exhaust when being heated to the working temperature (there was no excess exhaust when it was cold). The only reason for excess exhaust I could think of was the presence of oil in the combustion chamber. That’s why I removed the cylinder head and cylinder to check what might be wrong. Here is that I found when checking the cylinder.
Such a huge damage was obviously caused by a wrist pin. My guess is that the lock ring on that side of the wrist pin got destroyed due to some reason, that’s why the wrist pin started to move away from its initial position damaging the cylinder. I asked a few engine specialists about my situation and they said that it’s a rather common case – some lock rings are of poor quality and might get destroyed by constant cold-heat cycles. Another possible reason is metal fatigue, especially when it comes to cossack motorcycles – most spare parts you can find on the market were produced decades ago, long before the ugly monster called the ussr was finally destroyed.
Anyway, I was more interested in finding a solution to prevent a similar problem in the future than finding the exact cause of the problem, and I found it 🙂
Do you drink wine? Do you know someone who does? I myself don’t drink any alcohol (and I strongly advise you to stay away from alcohol, tobacco, drugs and other crap and keep your bodies healthy and sound), but I have friends who do and they were the ones I turned to for help – I needed a simple wine cork, the one that is used to seal wine bottles.
I took the cork I was given, cut down two small pieces from it and placed them between the cylinder and the lock rings.
The trick is quite simple – even if some lock ring will get destroyed (due to any reason), the cork piece won’t let it leave its place and thus it will continue keeping the wrist pin on its place.
Don’t worry about placing a piece of wood it your cylinders. A cork is very soft and won’t damage cylinders while being durable enough to be used this way.
Don’t forget to use a cork the next time you take off your cylinders. This might save you from the situation I faced this weekend.