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Oil-drenched engine

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  #201  
Old 05-15-2015, 08:52 AM
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That looks like #4 is on TDC of the compression stroke.

Turn the crank another turn. You might want to bolt the cams down first though.
 
  #202  
Old 05-15-2015, 09:33 AM
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Originally Posted by Migge
So... not much has happened, but I'll get to work this weekend. But before I do anything, I would like to ask you of this could possibly the wrong timing. I know you don't see the pulse generator sprocket but assuming it's put on the proper way, like the only way, this is what it would look like when the cam chain is on, right? The reason I'm asking is this pro mechanic told me that the lobes on cylinder 1 should be pointing like a V, angling backwards on the intake valve and forward on the exhaust valve. But aligning the markings of the sprockets (which I never removed from the cams) with the surface of the head gives me this angle of the lobes. He also states that me seemingly being one tooth off on the chain would not cause it not to start. Maybe run bad, but it would start. Any thoughts, guys?
Your mechanic is right about being one tooth off would cause it to run bad, but it would still start.

He's also right about the angle of the lobes. I'm going to walk through this out loud and hope I don't miss anything.

From what I can tell by the pic, everything looks good. The cam marks line up with the edge of the head. Intake cam is on the left. Cylinder #1 is on the far end of the engine, #4 is next to the cams. The lobes on #1 are forming an upward 'V'. This means the piston 'should' be at top dead center and #1 will be on the power stroke for the next 90 degrees. After 90 degrees, since the engine is rotating clockwise, the exhaust lobe for #1 will be pointing down and forward. At that point you are starting the exhaust stroke and in the next 90 degrees the cam will open the exhaust valve. So that all looks correct to me. #4 is opposite #1, so when #1 is on the power stroke, #4 is on the intake and in the pic, intake lobe is pointing down and forward, so it also looks to be in the correct position.

So since that all looks correct, the question is, where is the piston right now. Pull out the spark plug on #1. Put a long dowel rod (or pencil) down the hole until it hits the piston. Now rotate the engine forward and backward slightly. The rod should rise and fall each direction with the highest point being TDC. When you find that, your cam alignment marks should still be in the same position as in the pic. If they aren't, then the crank is off.

FYI, I personally don't believe ignition advancers are worth it. I'd beg, borrow or steal a stock one and put it on until you've got this running.
 
  #203  
Old 05-15-2015, 10:44 AM
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Phil's right. I was looking at it like a car motor with #1 next to the chain.
 
  #204  
Old 05-15-2015, 12:44 PM
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And this is why I want to gather all of you here in Sweden and buy you beer and make you pulled pork sandwiches. A big happy CBR F2-family, roaming the streets of my lovely Stockholm. Now I'm really eager to get back to wrenching on my baby. All I've done the last couple of days is help other people with their bikes, it's time to show my own a bit of love.

Oh, I haven't heard of ignition advancers before, but I take it it's some kind of device that let's control the spark in regards to the stroke? Doesn't really matter, after having bought that KTM 690, I'm running on financial fumes...
 
  #205  
Old 05-15-2015, 05:08 PM
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Originally Posted by Migge
And this is why I want to gather all of you here in Sweden and buy you beer and make you pulled pork sandwiches. A big happy CBR F2-family, roaming the streets of my lovely Stockholm. Now I'm really eager to get back to wrenching on my baby. All I've done the last couple of days is help other people with their bikes, it's time to show my own a bit of love.

Oh, I haven't heard of ignition advancers before, but I take it it's some kind of device that let's control the spark in regards to the stroke? Doesn't really matter, after having bought that KTM 690, I'm running on financial fumes...
I can translate. Ignition advancer = pulse generator sprocket.
The reason 'aftermarket' ones are sometimes called ignition advancers is because the teeth on the outside of the pulse sprocket can be offset by 2,4 or 6 degrees. Some of them are adjustable. Moving those teeth, in effect, advances the spark in relation to the piston position. In theory, this can improve top end at the expense of some midrange. But it varies wildly from bike to bike. In general they do very little for F2s.
 

Last edited by Phil314; 05-15-2015 at 10:15 PM.
  #206  
Old 05-16-2015, 02:32 AM
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Thanks, Phil! I thought it was some kind of cool gadget to connect to the coils... First order of business: Order stock puls generator sprocket. Mine is aftermarket so I better try with an OEM first. An ignition advancer combined with me being a little of on TDC would probably tip the scale in the wrong direction, especially if you aren't aware of either of these two. Once I get a hold of an OEM sprocket, I'll try that one out rather than experimenting with the one I have now.
 
  #207  
Old 05-16-2015, 06:24 AM
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Let someone with an air wrench break it loose. Its the same scenario as the clutch basket, you'll need to keep the engine from churning.

But, they're usually only 2°-6° advance, and I don't think even being a tooth off with it would keep the bike from cranking.

I had a 4° one on my F3, not too much of a difference (like Phil said). But, there's nothing wrong with going back to stock in order to figure it out.
 
  #208  
Old 05-30-2015, 01:31 PM
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Turns out I was wrong. My timing was off. When TDC on cylinder 1, the sprocket looked like this:


I wrote a long post about this on my blog (see my signature) but you guys were right all along and I was too sure of myself to see it. There might be other problems left to solve, but this is at least a great step in the right direction. By the way, working on the engine still in frame is possible but not comfortable .
 
  #209  
Old 06-03-2015, 03:12 PM
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Conrice, I borrowed an impact wrench (electrical one though) from work and man, was it easy to remove the bolt or what? I really need to get one. They are expensive but proper tools makes it more fun to wrench. Anyways, the new OEM sprocket with the correct markings is now mounted which probably helps when adjusting the timing...

 
  #210  
Old 06-03-2015, 03:22 PM
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The guys at the .ORG! forum have spoken highly of the Biltema electric ones. Exactly the same machine that some "pro" shops sell for over double the price with fancy stickers on, have been thinking about getting one myself when it gets time to swap the studs back under the cars.
 


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