Hello, Carpedians.
As some of you might have seen, my journey of swapping the engine on mk1 has been succesfull... as the swap goes. Though looks like it was all for nought.
After 20 miles old problems came back. And I am lost again what to do.
A quick bit of history:
Had problems with the bike since I bought it, my mechanic (who I don't particularly trust now and he's out of business, ahem ahem, maybe for a reason) tried to find the problem, done a few things and eventually told me it was an engine problem. I believed him, as I don't have no experience, apart from lubing the chain and pumping the tires.
Swapped the engine, but same problems again, meaning either both engines have same issues (fairly unlikely, I think) or problem somewhere else.
Problems after the engine swap:
Running engine, let's say 3000-3500 rpm, it starts twitching, and it's quite bad, makes the whole bike twitch with me on top of it. Higher revs seem to be ok. Smokes a fair bit, I think it runs rich.
Engine cuts off on idle, though starts up again ok.
Problems before the engine swap:
All above, plus the spark plugs get covered in black stuff fairly soon and then it won't start until new plugs get fitted.
Fuel consumption seemed very high, but hard to tell exactly as I wasn't riding it very much.
When I swapped the engine, I left the old carbs on. My only idea is smth wrong with carbs, which I have no idea what it could be. My mechanic said that the first thing he's done was to calibrate and clean the carbs, but after that very soon the problem appeared again. Maybe he didn't do anything and just took the money off me.
Other things to mention is:
After replacing the engine, couldn't get the carbs fully back on the engine intakes, the rubbers seem to be too short, so it overlaps maybe just by 2mm, could this make the engine run rich? Can't remember how it was sitting when I was removing everything from the bike.
Also, when I pull out the choke, the engine runs the same, it doesn't seem to change anything, or very little, maybe this also could be the culprit? I've replaced the cable and when choke is pushed in, the plastic bit on carbs seem pushed in all they way though.
I don't have the access to a garage anymore and keep my tdm on the street, so unless I find to temporary rent one, I'll have to get the bike to a mechanic (different this time), but before I go there, I really want all your ideas and opinions about what would be good things to check next. I'd kindly ask you to be as thorough with your replies as possible, as I still don't understand so many things about bikes.
Many thanks to you all and I look forward to your ideas!