New engine chirping and running on 2 cylinders | Page 2 | GTAMotorcycle.com

New engine chirping and running on 2 cylinders

What's supposed to be lined up here? I see a line on the flywheel lined up almost exactly with an arrow on the block.
 
Also, not sure if it's ignition timing related. If 1 and 2 can fire, 3 4 should be able to fire b/c the ignition system only sees 1&4 and 2&3... assuming everything fires 180 degrees apart but I can't see how it would be otherwise
 
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I already pulled the cover, and I believe I've found the culprit.

Looks like the timing rotor/flywheel may have moved relative to the crankshaft. If I visually set piston #1 at TDC, with the cam lobes pointing directly away from each other, the "T" mark on the rotor is off by a handful of degrees.

97b70a7b5192281d2c7adf5a41bfe053.jpg


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Discrepancy doesn't seem all that large though, and the cams do seem to be in sync with piston 1's TDC.

Should I pull that rotor? (If so, what kind of puller do I need?)

this is interesting.
timing marks would effect all 4 cyl's. it wouldn't make sense to me that it effects two cyl's but not the others. timing marks do look to be off a bit though....
food for thought, if the wire splicing .... I'd look long and hard at the splicing. if you trust the previous owner that the engine is a good runner...the only thing that has changed is the wire splicing.
 
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I think that is supposed to be keyed to the crankshaft... but the "key" might be removable and possibly left out? Just going by the fiche and it's a bit ambiguous

Yes, Woodruff key. I want to pull the rotor to see if it's actually there. Guy who rebuilt the engine now thinks it may have sheared.

What's supposed to be lined up here? I see a line on the flywheel lined up almost exactly with an arrow on the block.

Mark on the crankcase is supposed to be lined up with the line next to the T on the rotor.

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I said it was off by a handful of degrees but it's more like 10+.
 
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Also, not sure if it's ignition timing related. If 1 and 2 can fire, 3 4 should be able to fire b/c the ignition system only sees 1&4 and 2&3... assuming everything fires 180 degrees apart but I can't see how it would be otherwise

this is interesting.
timing marks would effect all 4 cyl's. it wouldn't make sense to me that it effects two cyl's but not the others.

True, but maybe 1&2 are borderline while 3&4 are ever so slightly more off so they don't fire? I dunno, I'm just spitballing.

I do think that rotor needs to come off to check whether that Woodruff key is in there. Unless someone has a better plan for the ol' girl and I.
 
What if only one pickup coil is working?

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I would focus on your timing approach first if those marks are supposed to line up.
 
I've been looking at a radian repair manual, but it's a bit different inside. On that one the T on the rotor is supposed to be directly under the pickup at TDCC. Yours is no where near that position either.

How would a key get sheared on a rotor? That's an ugly shape to get a puller on too.
 
No clue how it would shear. I'm thinking rather that it came out during reassembly and is stuck somewhere behind the rotor.

And yeah it looks like I might need something bike-specific, or at least specific to this type of rotor assembly.
 
True, but maybe 1&2 are borderline while 3&4 are ever so slightly more off so they don't fire? I dunno, I'm just spitballing.

I do think that rotor needs to come off to check whether that Woodruff key is in there. Unless someone has a better plan for the ol' girl and I.

spit balling lol. puller time, agree with you. or I mean spitballing with you. dang.
I thought for sure it would fire up on all 4 after switching around the spark plug leads on the non firing side....
 
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Haynes manual says to "use a tool like this one" with no other info. Gee, thanks.

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Step 11 tells you its a rotor puller, basically just a bolt, threads in to the end of the crank and the rotor pops right off once the puller bottoms out. Might have to tap it with a hammer at the end..
 
I guess it's just a reverse threaded bolt?

as long as the puller has correct matching threads your good to go. likely a reverse thread. tap as pointed out by bobj. they can be sticky

you should be able to turn it in by hand at first if threads are correct. its made of hardened steel.
 
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as long as the puller has correct matching threads your good to go. likely a reverse thread. tap as pointed out by bobj. they can be sticky

you should be able to turn it in by hand at first if threads are correct. its made of hardened steel.


EDIT the rotor threads may be right hand thread, if it is, you could use a long hardened bolt to remove rotor. sorry bobjohnson, I think that you may have been conveying that earlier.
 
Yeah, I used my caliper and thread gauge on it and turns out it's just an M16x1.5 right hand thread.

So I started looking around for something I might have in that size.... hmmm... I wonder what size my bar ends are... what are the odds... I don't need to tell GTAM I tried to pull my rotor with a bar end... let's see... oh ****!

aa9f802f5befbf75ce3ffa24be4d680f.jpg


Perfect match. It's not long enough though. Ima need to source a longer bolt tomorrow. Where does one procure an M16x1.5 bolt, at least 4 inches in length?
 
Yeah, I used my caliper and thread gauge on it and turns out it's just an M16x1.5 right hand thread.

So I started looking around for something I might have in that size.... hmmm... I wonder what size my bar ends are... what are the odds... I don't need to tell GTAM I tried to pull my rotor with a bar end... let's see... oh ****!

aa9f802f5befbf75ce3ffa24be4d680f.jpg


Perfect match. It's not long enough though. Ima need to source a longer bolt tomorrow. Where does one procure an M16x1.5 bolt, at least 4 inches in length?

hey thats great, now you know what bolt size to look for.
 
If you are going to screw around with bikes, you should have the tools.
Get something like this http://pi.roostin.com/images/items/large/BMS/BMS005S/X001-Y001.jpg
They're cheap and will pull "most" rotors.
DO NOT hit the rotor with a hammer. That would weaken or break the magnets. If you think you have to wallop the rotor use a dead blow hammer or a mallet or a big chunk of wood.

The motor/ignition has only one pick up, that fires when a raised spot on the outside of the rotor goes by the pick up. Some ignitions have one raised spot on the rotor, some two.

You don't need a longer 16mm bolt. Find a dowel that fits in the hole, that almost comes to the top, leave enough room to thread in the thing in the picture. Tension it as much as you can, then wallop the rotor with a 2x4. It should come off.
If the woodruff key sheared, it wasn't installed correctly. I run race bikes at 12,000 rpm with no key with no issues. There should be no load on that key, it is to locate the rotor when installing.
 
Yes, I've been reading about sheared woodruff keys this evening, interesting stuff. It sounds like the flywheel wasn't torqued down properly - removing the nut at the end of the crank took very little effort. It probably was torqued to 20-25 ft/lbs at most. Manual is calling for 58ft/lbs.

I ordered the proper flywheel puller (Motion Pro 08-0027 for the record) and some grinding compound to lap the flywheel and crank mating surfaces before reassembling.

Hopefully the sheared key comes out easily.


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