How to get the right stroke (TDC) on crank while cams out

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Maximus

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I’m replacing the cam chain & tensioner and forgot about mechanic basic. Prior to install the new chain, the TDC mark on crank shaft position sensor was a bit off. So bad thing is! I thing I went only a full turn instead of two. Both not sure!

Now how do I know, I install the cams on the right stroke?

 
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I’m replacing the cam chain & tensioner and forgot about mechanic basic. Prior to install the new chain, the TDC mark on crank shaft position sensor was a bit off. So bad thing is! I thing I went only a full turn instead of two. Both not sure!Now how do I know, I install the cams on the right stroke?
If the number one cylinder is up then you can start from there getting the cams back in correctly.

 
...now how do I know, I install the cams on the right stroke?
Maximus

The crank shaft rotates 2 times for every 1 rotation of the cam shaft. As Charismaticmegafauna pointed out, when you put the cam shafts back in set them to TDC on cylinder #1. It makes no difference how many times you rotated the crank shaft while both cams were out.

:)

Brodie

 
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Thanks! For the fast reply!

Now I can get a good night sleep! And graduated from dummy to 1st grade! LoL

Cams are on TDC and cams timing marks aligned and if for sure the spark plugs will ignite on the right stroke (compression).

 
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Do not turn the motor over with the cams in and the chain off ! If you have to turn the motor a revolution with the chain off then remove the cams. I think this is an interference motor.

The cams are what designate the stroke. So as long as crank is lined up with cams your OK.

Use your FSM and start at the beginning of "Installing the camshafts", but line up the crank before you put the cams in.

edit; sorry about the bold printed warning. I just saw in the title both cams out.

 
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Do not turn the motor over with the cams in and the chain off ! If you have to turn the motor a revolution with the chain off then remove the cams. I think this is an interference motor.
The cams are what designate the stroke. So as long as crank is lined up with cams your OK.

Use your FSM and start at the beginning of "Installing the camshafts", but line up the crank before you put the cams in.

edit; sorry about the bold printed warning. I just saw in the title both cams out.
Exactly, and don't worry about the spark plug firing. The plugs fire at top dead center on compression and exaust so it will work out either way.

Yes this is an inteference motor. It's been proven.

 
Sorry to resurrect an old thread, but this hits closest to my set of questions.

I adjusted valves on my FJR today, put it back together, and found that in an effort to put them in the middle of the adjustment range, I over-shot and need to go back where it was before. I forgot about positioning the motor in a specific position and took the intake cam off. I tried to put it back on and turn the engine, but it bound up somewhere, and rather than push anything, I assumed the cam chain jumped a tooth. Long story short, I now have both cams off, and I have no idea which side of the stroke the engine is in. I planned on sticking a dowel rod in the spark plug hole of the #1 cylinder, but I can't find anywhere that anyone actually defines which is what cylinder. From what I have seen, I'm guessing the far left (sitting on the bike) cylinder is #1.

What I need is:

Clarification- far left cylinder is #1, and when mark on engine timing plate lines up is at TDC.

I don't know exactly what mark on the timing plate to use. I see what I think are the marks, but there is no mark on the engine casting to line up with. It must not need precision, just approximately horizontal?

I took the camshafts off to mark the rear of the cam sprocket, but from what I have read people just line up the holes in the shafts instead.

Any additional help/pictures would be awesome! Where do I go from here, etc.

 
Sorry to resurrect an old thread, but this hits closest to my set of questions.
I adjusted valves on my FJR today, put it back together, and found that in an effort to put them in the middle of the adjustment range, I over-shot and need to go back where it was before. I forgot about positioning the motor in a specific position and took the intake cam off. I tried to put it back on and turn the engine, but it bound up somewhere, and rather than push anything, I assumed the cam chain jumped a tooth. Long story short, I now have both cams off, and I have no idea which side of the stroke the engine is in. I planned on sticking a dowel rod in the spark plug hole of the #1 cylinder, but I can't find anywhere that anyone actually defines which is what cylinder. From what I have seen, I'm guessing the far left (sitting on the bike) cylinder is #1.

What I need is:

Clarification- far left cylinder is #1, and when mark on engine timing plate lines up is at TDC.

I don't know exactly what mark on the timing plate to use. I see what I think are the marks, but there is no mark on the engine casting to line up with. It must not need precision, just approximately horizontal?

I took the camshafts off to mark the rear of the cam sprocket, but from what I have read people just line up the holes in the shafts instead.

Any additional help/pictures would be awesome! Where do I go from here, etc.
The mark on the engine casing you're looking for is the seam between the upper and lower crankcase halves. https://i75.photobucket.com/albums/i287/leavy1/Bike/FJR%20Transmission%20Disassembly/SAM_0579.jpg I believe my engine was on TDC #1 when I toook that picture. Follow the service manual procedure on installing the camshafts; IIRC the drilled holes on the camshafts face upward toward the casting marks on the cam bearing caps. Make sure that you take the slack out of the cam chain when you're lining up the holes.

 
If you don't have the manual stop and immediately go get one. It walks you through this procedure exactly.

The far left cyclical is number one. With both cams out and that piston all the way up you can start there putting the cams back in correctly. Pull the spark plug to find tdc.

 
Sorry to resurrect an old thread, but this hits closest to my set of questions.
I adjusted valves on my FJR today, put it back together, and found that in an effort to put them in the middle of the adjustment range, I over-shot and need to go back where it was before. I forgot about positioning the motor in a specific position and took the intake cam off. I tried to put it back on and turn the engine, but it bound up somewhere, and rather than push anything, I assumed the cam chain jumped a tooth. Long story short, I now have both cams off, and I have no idea which side of the stroke the engine is in. I planned on sticking a dowel rod in the spark plug hole of the #1 cylinder, but I can't find anywhere that anyone actually defines which is what cylinder. From what I have seen, I'm guessing the far left (sitting on the bike) cylinder is #1.

What I need is:

Clarification- far left cylinder is #1, and when mark on engine timing plate lines up is at TDC.

I don't know exactly what mark on the timing plate to use. I see what I think are the marks, but there is no mark on the engine casting to line up with. It must not need precision, just approximately horizontal?

I took the camshafts off to mark the rear of the cam sprocket, but from what I have read people just line up the holes in the shafts instead.

Any additional help/pictures would be awesome! Where do I go from here, etc.
The mark on the engine casing you're looking for is the seam between the upper and lower crankcase halves. https://i75.photobucket.com/albums/i287/leavy1/Bike/FJR%20Transmission%20Disassembly/SAM_0579.jpg I believe my engine was on TDC #1 when I toook that picture. Follow the service manual procedure on installing the camshafts; IIRC the drilled holes on the camshafts face upward toward the casting marks on the cam bearing caps. Make sure that you take the slack out of the cam chain when you're lining up the holes.
One thing I learned the hard way, the intake and exhaust cams are the same, so there are two sets of drilled holes on each. one for intake timing and one for exhaust timing. So, you need the diagram from the service manual or a picture from someone showing the relative position of the cams in order to get it right.

 
Got the bike buttoned back up... trying to get it re-filled with coolant. I did find a really nice way to put the CCT screw back in- I had one of those extendable claw things (since I threw the bolt into the frame trying to install it by hand) like this- https://www.amazon.com/Vim-Tools-FC24-Flexible-Pickup/dp/B000I1V8L6/ref=sr_1_1?ie=UTF8&qid=1358125299&sr=8-1&keywords=claw+type+flexible

And it fit perfectly through the hole in the frame with the claws retracted. I used needle-nosed pliers to hold the threads of the screw (gently of course) and grabbed the head of the bolt with the claws. Then I had a straight shot with a secured bolt and spun it right in. Worked like a charm!

Thanks everyone!

 
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