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Discussion Starter · #1 ·
I installed an updated cam tensioner in my CB360 which was worthless as it already had an upgraded version but the frame VIN was stamped rather than the motor. Peace of mind I guess. That took about 2 hours, now I have put about 30+ hours (lots of curse words and wrench throwing) into trying to set the points/timing with no success. I have something seriously jacked up. I set the left point to open exactly on the LF mark (with the 12v bulb set up) after the intake valve opens into the cylinder and then closes. The right point was set to open exactly on the F mark 180 degrees later. I have done this 20+ times and 1 time I got the bike to start and it backfired and ran like he!!. Now I have spark to both plugs (grounded on the motor) but I cannot get the bike to run at all.

When I reinstalled the points, I put them back on as removed, without turning the crank at all, and they were maybe a 1/2" off the LF and F mark so I just don't see how they could be a complete revolution off (firing on exhaust rather than intake) but it seems they could be with the backfiring and such. The bike was running good prior to removing the points plate to change the tensioner as well. Any ideas would be appreciated as I'm at the end of my rope with the points.
 

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Sensei
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The only things I can think of off hand are ...you have the coil to point wires swapped (left side coil fires off right side points)..OR, the cam to crank timing is off.....
First, check that the cam index is correctly aligned at TDC on the left piston (LT).....
Then manually break the left (front of engine) points and make sure the left coil/plug spark.....
I apologise if you've already done this, but we have to start by knowing these are correct before trying anything else...
Let us know.... Steve
 

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Just so we're not skipping anything... fuel is getting to the carbs right? Fuel valve is on, plenty of fuel in the tank? Plugs are sparking? The handlebar switch is in the "on/run" position?

Sometimes when we're focused on one area and convinced that's got to be it we don't think about the other little things.

Just trying to help.
 

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It takes a great deal of patience but you'll get it eventually. Just follow the tutorial put on by the fellas here. Not sure how to find the link.
 

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Discussion Starter · #7 ·
I hope the cam timing didn't get changed. I didn't take the cam chain off and tried not to move the cam at all with the valve cover off. Something is definitely jacked though as even if the timing was slightly off, I doubt it would cause it to run like it is.
 

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Sensei
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My GUESS was that when the tensioner parts were removed, there was enough "slack" in the camchain to "skip" on the crankshaft...One tooth off on the crank would be equivalent to two teeth off on the camshaft......
This is easy to check on the 360.... set crank to LT index, and check that the aligning marks on the camshaft gear are parallel to the top cover gasket surface..... Then check that you are on the correct stroke (both left valves should be fully closed, NO tappet pressure).....If it passes this test, it's something else, probably points or carbs......But let's take one step at a time so we can determine the exact original problem.....
 

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Discussion Starter · #9 ·
The points are firing the correct plugs and the cam was up at top left. I got it running with light backfire on left and gas smelling smoke out the right pipe. I timed left by adjusting plate and right with gap adjustment only. Both are in spec and seem to be exactly on lf and f. Maybe a timing gun will help.
 

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Discussion Starter · #10 ·
Steve, that is a good possibility. I had to put a lot of pressure on the tensioner to get it back in. From what you are saying to try I'll need to pull the top off again correct?
 

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Sensei
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Not sure what you mean by "and the cam was up at top left", but you NEED to be sure the cam timing is absolutely correct....Anything else is a waste of time IF it's not..... Pop the cover off and CHECK!....Only takes a few minutes, and could solve the problem.....

PS... Don't mean to sound harsh, but have to establish some baselines....one tooth off could result in your symptoms.... :?
 

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Discussion Starter · #12 ·
It does appear that the right mark is about 2mm lower than the left mark at lt. Should I pull the tensioner and try to move the chain one notch?
 

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If the lines are not perfectly level with the top end you are in for trouble.
 

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Discussion Starter · #15 ·
Well it lines up without the tensioner on but as soon as I put the tensioner on it throws it off when the slack is removed. The chain is pretty tight though I really cannot grasp that it would move over a tooth on the crank or cam.
 

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Discussion Starter · #16 ·
Ok, with the tensioner on it is 2 mm up on the left. 1 cam link is 8mm so if I mone it back 1 it will be up 6 mm on the right. I know it didn't move a link on the cam when I had it apart so I can't move it a link without throwing it way out of balance at left tdc right?
 

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Sensei
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You KNOW it didn't move a link (up top), but the slack might have allowed it to "jump" position on the crankshaft gear..............

The 360 tensioner applies all (or most) of the "slack removal" to the back (carb) side of the camchain.....You'll want the front (left, viewed from the bikes left side) to be a smidge too low (if anything) so that when the slack is pulled out, the chain tension will return it (clockwise) to the correct alignment... Also, make SURE the tensioner damper bar (the one with a metal loop at each end) is inserted correctly, and sits between 8 and 15mm above the sealing surface before you install the upper tensioner holder......


It is also possible that the camchain itself is worn (stretched) beyond its allowable limits.....This can be checked by measuring the depth to the tensioner rod from the port of the access hole on the engine front/bottom.....13.0 to 13.6mm is usually the spec....Some early engines (pre 200079) are different depending on serial number.... Camchain replacement involves major engine disassembly.......
 

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Discussion Starter · #18 ·
Steve, exactly. I think I figured it out last night. I didn't use a the push bar tool as I couldn't locate one anywhere on the internet and the bottom damper shifted up and out of spec. This in combination with the tensioner not being bent exactly right, I believe is putting too much pressure on the cam chain and moving the cam too far right. I'm going to see if I can find a long bolt that fits the threads of the push bar and proceed.
 

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Those cam marks don't look too bad in the photos.
You never answered as to whether or not you used the procedure on this site to set the ignition timing.
Sounds to me like your right side is so far off it won't start or run right........
 
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