HondaCB650

this is for piston #3. I was able to do #1 intake. I backed out the adjusting screw completely and just properly bolted the cover on after backing out all adjusting screws. Everything looks great. What's wrong now?

Might I have over tightened the cover? I used a dial torque wrench. I did notice that before it got to 9 ft/lbs the it seemed to slip a little, hopefully not stripping but that's just probably moving past some dirt in the threads. But I stopped torqing shortly after. Ideas? Thanks

well I just rotated the crankshaft fully once just for kicks and noticed the cam lobe didnt come back up this time lol. Does this mean I can proceed and repeat if need be for the rest of the procedure?

okay, It's all good. Idk what happened. I thought 1 and 3 were supposed to be aligned or something and somehow at least t I thought I was able to adjust #1 tappet successfully but I had to rotate it 360 to get at #3, finished whatever valves from there, rotated 360, did the last set. So in retrospect Im thinking I should recheck #1. I have to go back now anyway to fix an oil leak I caused. Well at least I'm that much closer to understanding how valves, sensitive mating surfaces and carburetors work. I just need to stop costing myself for my education. Anyway..

juntjoo wrote:well I just rotated the crankshaft fully once just for kicks and noticed the cam lobe didnt come back up this time lol. Does this mean I can proceed and repeat if need be for the rest of the procedure?

I was gonna mention that the cam lobe in your picture was not in the proper position to be checking the clearance.

A good tip when you adjust those rocker arms is to rotate the engine to see if the camshaft is moving and also to move the lobe away so you should be able to use the feeler gauge.

Folsoml wrote:

juntjoo wrote:well I just rotated the crankshaft fully once just for kicks and noticed the cam lobe didnt come back up this time lol. Does this mean I can proceed and repeat if need be for the rest of the procedure?

I was gonna mention that the cam lobe in your picture was not in the proper position to be checking the clearance.

what do you mean by that? the timing mark says "1.4" and per the book it says to do intake for #3. I'm back now. Just put the cover(s) on. Notice in this pic I have it positioned a touch beyond tdc to show where it will fit. This can't be right. See this is what happened the first time. My timing marks tell you for which cylinders you're at, "1.4", or "2.3". I didn't notice this before. So this is concerning.

MEHall wrote:A good tip when you adjust those rocker arms is to rotate the engine to see if the camshaft is moving and also to move the lobe away so you should be able to use the feeler gauge.

hey, when ya get a chance pls check my prev post. thx

as per the book 3 (and 2) is done at 2 diff rotations. In truth the Mark dont matter as long as your off the lobe.

cb650 wrote:as per the book 3 (and 2) is done at 2 diff rotations. In truth the Mark dont matter as long as your off the lobe.

really?? Somehow I distrust that advice, from my experience small fractions of millimeters off can be disastrous.

okay, I refuse to spend another week at this. I demand this discrepancy to be reconciled by simply doing all adjustments with that 2mm advanced position keeping it all uniform. please pray for me...

no no, I got it. can't believe I did it like I described. I was confused about rotations of the cs per cycle and lobe position and how many TDC's to go through for a cycle... I believe I got it.

juntjoo wrote:

cb650 wrote:as per the book 3 (and 2) is done at 2 diff rotations. In truth the Mark dont matter as long as your off the lobe.

really?? Somehow I distrust that advice, from my experience small fractions of millimeters off can be disastrous.

Distrust all you want. I"m a moron just trying to steer you wrong.

BTW I have owned one from 83 and have several now but dont know what Im talking about LOL

cb650 wrote:

juntjoo wrote:

cb650 wrote:as per the book 3 (and 2) is done at 2 diff rotations. In truth the Mark dont matter as long as your off the lobe.

really?? Somehow I distrust that advice, from my experience small fractions of millimeters off can be disastrous.

Distrust all you want. I"m a moron just trying to steer you wrong.

BTW I have owned one from 83 and have several now but dont know what Im talking about LOL

No it's just that I don't know enough to judge what you're telling me. But I can consider it and am still trying to figure out how it works and it seems to me the clearance specified is for where the lobe and tappet meet at tdc, that making that clearance any before or after would change the clearance at tdc, if you're adjusting somewhere else other than tdc. If a couple millimeters didn't matter then why bother with these feeler blades of such tiny thicknesses? But maybe I'm missing something, but I got it figured out so I could do it by the book. From a vid I saw I got the tip that bypasses all the guesswork from all the other tricks to find the right tdc: the guy said to just take the pass of the correct tdc(1.4 or 2.3) that has all your valves for this set all have clearance. When one doesn't, you just gotta go around again. That worked. Should have the first two times but I was just too confused how the cam and crank shafts related to each other. Anyway, thanks

jj, CB is correct about it doesn't have to be exact as the gap should be the same on the round part of the cam before it gets to the lobe. But considering your own proclaimed lack of experience with bikes, stick to the timing marks for peace of mind and one thing less to worry about.

juntjoo wrote:

cb650 wrote:as per the book 3 (and 2) is done at 2 diff rotations. In truth the Mark dont matter as long as your off the lobe.

really?? Somehow I distrust that advice, from my experience small fractions of millimeters off can be disastrous.

Take a look at this GIF of how a cam works. Notice that the cam is mostly round. Only on the lobe part does it have an affect on the tappet. The rest of the time, it is an equal distance away from the tappet. So if you check the clearance anywhere on the cam, as long as the lobe is off the tappet, the measurements should be the same.