Hello,
It`s been some while since last update. So I will write, what has happened since that.
I pulled out engine. Idea was, that valve seats are damaged. After removing both heads and cleaning them, discovered, that seats are almost perfect. Also other parts are not much worn out. What I found - it looked, that old head gaskets were with some silicone covered. It looked like very cheap "repair" done.
I disassembled heads, changed valve gaskets, cleaned everything.
Next problem was, that I put in removed heads camshafts (yes, I know, that in manual is written - do not do that), and it seemed strange to me, that I could not move them. After longer time of thinking, I understood, that design of heads is made that middle part is connected only with some tight aluminium parts (where chain goes). And heads align and are straight, only when bolted to the engine block. Still do not know, if it should be so, but when I bolted them back to the block, I could move camshafts very easy.
I had not time to do this repair every day. I went to the bike few hours in month, so it took quite long to put heads and engine back together correctly. After few more months engine, carbs and all other was back in bike. Started it and.... again one cylinder did not work. Or even two.
Took again off carbs and checked engine timing. Maybe there was some mistake... Manual for this bike is not the easiest what I have read. And especially timing marks are quite strange and do not match with written info in manual. So, I turned countless times the engine and finally went through all the engine timing with logic. All opening and closing intake / exhaust times looked correctly.
Checked and adjusted valve clearences.
Put back everything again, but now I decided to turn carbs by 180 degrees (so the front two carbs now were rear). It was not so difficult, just needed to make longer fuel hose and few more things. If problem were in engine, then nothing should change. If problem were in carbs, then there should not work other two cylinders. And, yes, I found, that problem were in carbs. But it seemed strange, because they were disassembled, cleaned and changed all rubber parts before one year.
I looked deeper in carbs and found, that at least two diaphragms were very loose (yes, I should check them earlier, but then I hadn't learned the construction of these carburetors yet). I decided, that it was time to disassemble them by myself. I also got many good advices from experienced carb mechanic. I disassembled them and found, that diaphragms were run off the seats, where middle of them is attached. Put them back and this time more accurately. It was most likely, because, when sitting on shelf, old fuel glued needles into seats. And when I started the bike, diaphragms run off the middle parts.
Also there were dirt in few of main jets and other parts. Cleaned everything and put back together.
Washed also fuel tank.
There were also few other smaller problems in the middle (like ventilator, what I damaged and repaired and few other).
In September 2025 bike again was running. I regulated idle with gas analyzer. Maybe engine is not perfect – when cold, on idle one cylinder still do some small coughing time to time, but I think it runs good. When hot, not any problems.
I gave myself a question - why carbs were clogged after one year sitting in shelf. And the answer was - in fuel tank there was some very old fuel left and it clogged everything, when I put carbs back after first cleaning in the very beginning. In Baltics, because of eco additives added by fuel retailers, gasoline is especially bio-active and makes many problems already after 6 months standing in tank. I do not know, how old was the fuel in tank, when I bought it. It was not much there and I added fresh fuel already in first ride to the garage. It was the largest mistake.
Only now I realize how powerful and well-handled this motorcycle is, despite its relatively high weight. There is no problem riding it also with two people. Aftermarket exhausts are a great value. They are not loud, but I really like the sound.
Hopefully I'll be able to go without major repairs for a while and slowly get it back to perfect condition.