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Old 11-04-2012, 10:11 AM   #61
Yachtie OP
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well i'm officially discouraged. Think i'm going to give up, hopefully can find a actual reputable mechanic for these airheads down here in south florida. Serves my right for buying a bike on ebay....
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Old 11-04-2012, 10:47 AM   #62
rufusswan
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Whoa there son. Let's not be throwin' out the baby with the bathwater.

Assuming you and others might be correct - that some jackleg was able to install the flywheel off kilter AND still got the new ignition system timed correctly, you are still riding a pretty damned nice bike.

Also, you are just unable to find TDC with assistance from said timing marks on the flywheel.

Get some white paint and a small brush + a couple of soda straws. Find TDC the old school way by sticking the straw into the spark plug hole and letting it tell you when you get to TDC, then paint one dot on the flywheel.

With a new TDC marked, do some looking and you should be able to properly adjust the valves. Things might all become 'well'.

If so, then you can address a later issue of 'moving' the flywheel.
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Old 11-04-2012, 11:02 AM   #63
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If that is what it is.. Flywheel in wrong position (sounds like it to me)... then that in itself is not a massive problem other than your timing marks being out so you don't have an accurate reference point.

I am sure there is a tool that you can use to determine TDC. I am also sure someone will shoot me down saying this is a bodge , but... On other bikes I have used a screwdriver.... Take the spark plug out, stick a long screwdriver or spoke in.. MAKE SURE YOU HAVE SOMETHING THAT YOU WILL NOT LOOSE THROUGH THE HOLE.. Long screw driver is best as it has a handle at other end that you will not fit through the spark plug hole.

Anyway... Slowly turn the engine over using the Allen wrench on the rotor and hold the screwdriver in your hand pressing down gently.. Gently.. On the crown of the piston.. After a few complete revolutions (and also noting the opening and closing of valves as mentioned previously) you will know how it feels / how far the screwdriver moves up.. When it is at its highest point this is TDC. You could in theory use some marker to make a new mark on the flywheel for this tdc position.

But then you would also need someway of calculating the Static and Full advance marks. Sorry don't know how that is measured..??. Anyone else got any suggestions for this?? Sure you could measure the distances with some sort of roller gauge on the flywheel then again re mark them??

From one airhead noob to another... Do not give up! You wil get there and when you do you will have a much better appreciation and empathy of how your bike is working. Spannering on the bike is half of the fun. If you are really feeling down over this, then take it to a good reputable airhead mechanic in your area. Ask him if you can sit with him while he works on it so you can learn from him... Take him a 6 pack of beer and give him a few extra for his troubles.

Good luck. Keep us posted with how you get on.

Byron
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Old 11-04-2012, 11:12 AM   #64
ME 109
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Forget timing mark for now.
Both spark plugs out.
Back off all four rocker adjusters so they are not contacting valves at any position (rotation) of the crank.
Bike on centre stand in 5th gear.
'Knock' the back wheel forwards with your right hand so it 'bit by bit' turns the engine.
While you are knocking the wheel and turning the engine over, stick your left thumb over the left hand spark plug hole and wait to feel the pressure building up under your thumb. As soon as you hear a 'fssssst' you know the piston is approaching top dead centre on 'compression'........ the ALL important compression.

You can put your dipstick in the spark plug hole and knock the wheel a little more until the dipstick is furthest out.
If at any point you can push the dipstick back in a little, you've gone past TDC.

Emphasis on 'as soon as you hear a fsssst'.........you are very close to TDC

Emphasis on backing off the rocker adjusters.........they may be holding the exhaust valve open at the wrong time, and you won't get a 'fsssst'

You can knock the wheel backwards too, if you go too far.

The dipstick won't hurt anything. It is the perfect tool, and will get you 'exactly' TDC if you want...

Then.....you can look for the timing marks and know if the flywheel is correctly placed.

Regardless of where the timing marks are, you now have the engine at TDC compression, on the left hand side.

Set your valve clearance LH side

Edit, Dammit, I've just seen an error in my method. If the adjusters are backed off completely, every TDC will be compression.
Now I have to go to work. Someone will hopefully correct me.
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Old 11-04-2012, 11:24 AM   #65
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Quote:
Originally Posted by Byron1 View Post
If that is what it is.. Flywheel in wrong position (sounds like it to me)... then that in itself is not a massive problem other than your timing marks being out so you don't have an accurate reference point.

I am sure there is a tool that you can use to determine TDC. I am also sure someone will shoot me down saying this is a bodge , but... On other bikes I have used a screwdriver.... Take the spark plug out, stick a long screwdriver or spoke in.. MAKE SURE YOU HAVE SOMETHING THAT YOU WILL NOT LOOSE THROUGH THE HOLE.. Long screw driver is best as it has a handle at other end that you will not fit through the spark plug hole.

Anyway... Slowly turn the engine over using the Allen wrench on the rotor and hold the screwdriver in your hand pressing down gently.. Gently.. On the crown of the piston.. After a few complete revolutions (and also noting the opening and closing of valves as mentioned previously) you will know how it feels / how far the screwdriver moves up.. When it is at its highest point this is TDC. You could in theory use some marker to make a new mark on the flywheel for this tdc position.

But then you would also need someway of calculating the Static and Full advance marks. Sorry don't know how that is measured..??. Anyone else got any suggestions for this?? Sure you could measure the distances with some sort of roller gauge on the flywheel then again re mark them??

From one airhead noob to another... Do not give up! You wil get there and when you do you will have a much better appreciation and empathy of how your bike is working. Spannering on the bike is half of the fun. If you are really feeling down over this, then take it to a good reputable airhead mechanic in your area. Ask him if you can sit with him while he works on it so you can learn from him... Take him a 6 pack of beer and give him a few extra for his troubles.

Good luck. Keep us posted with how you get on.

Byron
I've been googling for weeks trying to find a good mechanic down here and haven't found one yet.

Here's my latest dilemma. Assuming my flywheel is installed wrong. Trying your technique with the straw/scredriver, or just watching the valve and waiting for it to close fully before ajdjusting. the rocker arm is tight on the valve. So i go counter clockwise with the bolt it in order to get the right clearance, well the valve just keeps backing out as i spin the bolt so i get no clearance at all until i adjust the bolt 3-4 turns. Thats where i think i'm all screwed up, that shouldn't be happening right?
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Old 11-04-2012, 11:30 AM   #66
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I made one mistake in my last post, I said that TDC will be about 90*, 1 quarter turn of crank, from when the intake closes. It will be 180* after intake closes.

So now I see we have another problem. I'm sorry but I have to correct another member . I only know you from this site ME 109 and I have to tell you that your advice is wrong. So please if you want to learn this stuff write me, I will try to help.

Yachtie, use the drinking straw, or a chop stick from your favorite Chinese restaurant, to find TDC. Put a small paint dot or just mark the flywheel with a piece of chalk or a crayon. If the flywheel is not correctly indexed it is fixable and for now we can deal with it. Start by finding TDC and marking it.

I'm going back through this thread a little bit to read what has happened. I had to go to work. I'll be back soon.
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Old 11-04-2012, 11:35 AM   #67
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Originally Posted by disston View Post
I made one mistake in my last post, I said that TDC will be about 90*, 1 quarter turn of crank, from when the intake closes. It will be 180* after intake closes.

So now I see we have another problem. I'm sorry but I have to correct another member . I only know you from this site ME 109 and I have to tell you that your advice is wrong. So please if you want to learn this stuff write me, I will try to help.

Yachtie, use the drinking straw, or a chop stick from your favorite Chinese restaurant, to find TDC. Put a small paint dot or just mark the flywheel with a piece of chalk or a crayon. If the flywheel is not correctly indexed it is fixable and for now we can deal with it. Start by finding TDC and marking it.

I'm going back through this thread a little bit to read what has happened. I had to go to work. I'll be back soon.
well that 180* more turn on the crank sounds about right, thats what i was seeing.
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Old 11-04-2012, 12:21 PM   #68
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Alright now. You are making progress. It seems you have identified a problem, the flywheel incorrectly indexed, and so we will deal with that now. After you have marked the new TDC on the flywheel we will set the valves. BTW, your bike will be running today if you can stick with this a little longer. I'm sure this bike will run, might not be all that great, we still have to clear up a few other possible problems but it will run after the valves are set.

It is not rare at all for flywheels to be incorrectly installed. They are held onto the end of the crank shaft by 5 stout bolts. And that means they can be installed in 5 different positions. I have done it myself, but I caught the mistake before putting the transmission back on. The crank rotates 360* and each possible position is 72* from another. Of the 5 positions only one is correct.

Either turn the engine with a Hex key in the alternator bolt and the engine in neutral or by rotating the rear wheel with the trans in 5th gear. If the bolt in the alternator is in good shape and not buggered, not letting the Hex key start to slip, then I use that method. Do not damage the bolt. But I have no problem with this.

With a straw or a chop stick, you can not use some piece of a twig you picked up in the yard because it will get trapped in the plug hole and break, with both plugs out so the engine is easy to turn over, rotate the engine till you can feel the piston rising in the cylinder. You have to guide the straw or stick with one hand while turning the alternator bolt with the other because the stick can be pinched, it gets to too much of an angle and stops the piston from rising or the stick breaks.

You are going to mark the position of the TDC for the crank. This has nothing to do with the position of the cam shaft or the valves. For this operation pay no attention to the opening or closing of the valves. When you have found the position of the piston and it is at the top, rock it back a little and the stick starts to drop, rock it forward a bit and the stick starts to rise, when you have found the position of TDC you can mark the flywheel with a piece of chalk or crayon or a small daub of paint. The paint will be a permanent marking and there are advantages to this but we may want to fix the problem instead. You can always redo this operation to find TDC again if your chalk mark gets washed off but chalk or crayon will last for years so if they are handy use one of them.

You do want to always turn the bolt in the alternator in the right direction or the direction of tightening. If you turn it left or to unscrew it may come loose. Well for this operation you can rock the crank a little and use the left direction just don't hit the bolt with a big push and don't rock it backwards too much. If the bolt starts to unscrew just tighten it up and then you will not be able to rock the crank any more. You will be able to do this by just going forward. Just a little more frustrating.

We are only doing One thing here. Finding and marking TDC. There is an exact place. There are 360 separate degrees to this flywheel. Each of these is a very small amount of turn. Only a couple of millimeters (I'm sorry I don't have an exact figure) but we don't have to be 1 degree accurate even. If you get your mark with in several degrees of TDC it will be good enough. It's not hard to do. You will be with in one degree with no problem. That's close enough.

Bill is right, you may have to get professional help but I'm not giving up on you and I think you can do this. At the moment you are trying to make sense of it. Don't worry too much about making sense of this stuff. You will understand it all later. There have been a few well intentioned posters that confuse things because they don't understand. I know this is how we all learn. They will continue to give their philosophy of the operation of the internal combustion engine but some of the stuff you have gotten has been wrong. I'll continue to point this stuff out to you. So don't worry you are not going to make a mistake.
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Old 11-04-2012, 12:28 PM   #69
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well that 180* more turn on the crank sounds about right, thats what i was seeing.
That would be great if my mistake is all that happened here. Sorry about that. But I said 90 and the correct amount of turn of the crank after closing of the intake is 180 so the difference is 90, or another 90. If this is what you get when you watch the intake close, you get TDC after 180* turn of the crank then you can set both valves on the side that the intake closed on.

The trick for finding TDC with a straw is still a good one to know. It is not exactly common but I hear of two or three of these a year. You can still use it to see if you and I agree again or at all about what is happening.

I'm going to go back to my post that has this mistake and correct it so it won't mislead somebody else possibly.

Sorry for confusing your issue Mr Yachtie.
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Old 11-04-2012, 12:38 PM   #70
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All the above remarks about sticking "solid stuff" such as screwdrivers into the cylinder are wrong from my experience. These guys are just not accounting for the great strength of the rocker arm springs. You can try to turn the crank bit by bit, BUT when the valve spring take control the crank Fricking Rolls. It is all too easy to mark pistons and cylinder walls with a screwdriver. I have done it and it ain't fun nor smart.

TDC does NOT happen while the valve springs are working .. it will be between that happening. Use a soda straw or chop sticks as it's too easy to get something jammed in there.

You can do it.

Find it manually and mark the flywheel. Then go back to checking both sides to prove it all makes sense, and then you can adjust your valves properly.

You do not have to be accurate about TDC, most any ole motor such as we have has +- 2-3' or 5 or 6 degrees total during which the cam lobes are "off" the push rods or off TDC. Then you can or should be able to "spin the pushrods" as Hardware girl said. In the case of valve lash this is close enough.
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Old 11-04-2012, 12:44 PM   #71
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Originally Posted by Yachtie View Post
So looking again, The TDC mark actually comes into view I would say halfway into the intakes valves closing cycle On Both sides.
What you say here is the TDC mark appears while the intake is closing. If this is what you see you will have to remark the flywheel.
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Old 11-04-2012, 01:42 PM   #72
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What you say here is the TDC mark appears while the intake is closing. If this is what you see you will have to remark the flywheel.
I dont know what i see anymore haha. I'm going to take a hour breather and go to the gym. Then get back to it.

I replaced the rubber between the carbs and cylinders while taking a break from the valves, Just used radiator hose for the time being. Both were extremely cracked and dry rotted. I'm sure there was a leak for sure.

Back to the 90* 180* convo.

When looking at the left side, i saw the intake valve close, then looked at the sight hole and if i had to guess it was another 185-195* turn of the crank till i saw the TDC mark. Would you say thats fairly accurate.

I'll try the chop stick method later tonight to see if that is close to the mark. I did try and rock the rotor counter clockwise and the bolt did back out a bit, so i tightened it back up and only go to clockwise now.

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Old 11-04-2012, 03:38 PM   #73
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It may not seem so to you but you are making progress. The radiator hose is a good fix. I would not expect them to last for long though, who knows, but they weren't made for resistance to fuel.

The engine is a four stroke engine. The crank turns twice for each time the engine does this complete four stroke cycle. Let's work for now on getting one cylinder right because I think it is distracting to be looking at both cylinders and wondering how it all fits together. Leave the valve cover on the right side cylinder but take the plug out. Plugs out of both sides. If you have the cover off the right that's OK but we are not going to look at the right side cylinder till we are done with the left.

You probably should still check that the TDC mark is in the timing window at the same time the piston is at TDC. For this the position of the valves is irrelevant. With your chop stick in the spark plug hole held in your right hand, the engine turned with the hex key in the left hand. Guide the chop stick so it isn't pinched or trapped by the piston. It won't do any damage but we don't want to ruin a perfectly good chop stick. You can feel the piston coming up and the TDC mark should be in the window with in only 2 or 3 millimeters of actual TDC. You don't need any amount of accuracy. If they are close they are right. The TDC mark in the window, the piston at the furthest out from the block or top of it's travel.

Once it is established that the TDC mark is correct we will move onto the valve lash setting. Tell us at this point,"Is the flywheel correctly indexed or you have marked a new spot for TDC." Then we can move on. But we have to settle this point once and for all. We can not be doing the valve lash till we KNOW the flywheel is on correctly.
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Old 11-04-2012, 04:34 PM   #74
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It may not seem so to you but you are making progress. The radiator hose is a good fix. I would not expect them to last for long though, who knows, but they weren't made for resistance to fuel.

The engine is a four stroke engine. The crank turns twice for each time the engine does this complete four stroke cycle. Let's work for now on getting one cylinder right because I think it is distracting to be looking at both cylinders and wondering how it all fits together. Leave the valve cover on the right side cylinder but take the plug out. Plugs out of both sides. If you have the cover off the right that's OK but we are not going to look at the right side cylinder till we are done with the left.

You probably should still check that the TDC mark is in the timing window at the same time the piston is at TDC. For this the position of the valves is irrelevant. With your chop stick in the spark plug hole held in your right hand, the engine turned with the hex key in the left hand. Guide the chop stick so it isn't pinched or trapped by the piston. It won't do any damage but we don't want to ruin a perfectly good chop stick. You can feel the piston coming up and the TDC mark should be in the window with in only 2 or 3 millimeters of actual TDC. You don't need any amount of accuracy. If they are close they are right. The TDC mark in the window, the piston at the furthest out from the block or top of it's travel.

Once it is established that the TDC mark is correct we will move onto the valve lash setting. Tell us at this point,"Is the flywheel correctly indexed or you have marked a new spot for TDC." Then we can move on. But we have to settle this point once and for all. We can not be doing the valve lash till we KNOW the flywheel is on correctly.
Ok, did the straw technique, i could feel the piston movement. It felt that there was only a small little lip to catch the straw on, that about right? if so, i kept the straw on that felt it up and down, when it came up to the point where i could no longer tell if it was continually going up or down i checked the window and i could see marks. I wouldnt say it was smack dab on TO but it was very close, so i just moved it slightly to get TO center. Did the appropriate clearance, spun the rotor around 360 and did the right valve clearance. I also tighten the nuts and have no more up and down play in the rocker arms.

So i'm going to say i have done the valve clearance, going to try and start it up in a bit, and see how i did.
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Old 11-04-2012, 05:25 PM   #75
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It sounds like you were lucky to have the left side on compression when you set the valves. But I'm not one to smack a gift horse in the mouth.
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