apeonwheels wrote:I tried to tap it back after loosening the nut and unwedging the bolt. It moved a little bit but not enough, I was hitting it hard though. Still there is more than half a mm difference. I checked out the pics I made when I assembled the head, can`t see any obvious misalingment. I wonder I should take off the head cover and loosen the big nut to deliberate the other half of the camshaft. Is that doable leaving the motor in the frame?
First start with major oil leakage
G I spotted these as race cams due to the machined sides and you can see the left side has quite some lift and duration. ....................lm
Well, either with race or stock cams, it is running without leaking oil. My new problem is a strong smoking that I expected to disappear after a couple of mins running but it didn`t. The rings are supposed to be sealing, they looked new when I assembled them in. Since these engines don`t have valve seals, they should be ok, too. Any guess where the smoke is coming from? Another, perhaps related question: where is the breather pipe on the cylinder cover supposed to be connected to? I couldn`t find any inlet on the air filter.
Great pics................Good on You for getting it running. The top breather-tube trails down the cylinder between the carbs and across the valley cover..........then down below the swingarm to atmosphere.
Pistons.......a one-over is 0.25mm........hardly detectable in a pic. Your pistons resemble the 12-over (3mm) sitting on my shelf in bored cylinders. You can go more than 1 to 1.25mm over-size with the stock headgasket. The largest pistons require a custom head-gasket. Maybe your camera exaggerates a few details. Smoke........white or black? Immediate on start-up? One cylinder or both? Any change when riding under load? Check you plugs...........and carry spares until you get it sorted.
Last edited by OldScrambler on Tue Nov 17, 2015 12:41 pm, edited 1 time in total.
Hi Oldsrambler, thanks for your reply. I don`t remember the size of the pistons because I put the engine together about two years ago. But I think it wasn`t that large, it was the 1st or 2nd oversize. The smoke was white, but fortunately it got better the weekend when i let the engine run longer, it`s almost smokeless now :) probably the rings needed more time to wear in. The plugs: one is covered with soot, the other is wet from fuel. For some reason the mix is super rich, although I set everything for specs. I pulled apart the carbs and now I`m trying ti figure out what is the reason for this rich mixture. My guess is the aftermarket rebuild kit, which is such a good quality, made in Japan of course, that the float bowl gasket got swollen when it met the fuel for the first time, so now I need another pair that is fuel resistant. Another idea is that I left the carbs in cleaner for too long and it dissolved the material of the carbs as well not just the dirt.
Better to be rich than lean..............Check the pilot jets...............the mains don't really get used until mid-throttle under load.
Larger pistons tend to increase the fill-rate (flow) and also have a slightly positive compression gain. Getting the correct bowl-gaskets will help...........but you also may have slightly too much fuel in the bowls.........so check the float levels. If you are tuning the bike on the center-stand, you may find an improvement when your sitting on the bike with the rear wheel on pavement due to the reduced angle of the carbs. I like to do the final air-screw adjustment while sitting on the bike.
So far I have yet to find "fuel resistant" bowl gaskets. ..............lm
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