Valve adjustment no good?

[n4mwd]

Originally Posted by The_big_dill

Well, i will be going around stores tomorrow trying to find a replacement screw for the one that is stripped...

2 things that are on my mind. you mentioned that when someone rotates the crank and i have the extension down the hole with moderate pressure on the lever, what is suppose to happen in a functioning situation?

The other question, can i just use a flashlight to inspect the chain guides like motofool suggested, or would that not suffice?

When you are applying pressure on the CCT mechanism, the crank should rotate normally. When the internal CCT is broken, sometimes it will rub the clutch basket which can be felt when the crank is turned.

Also, if the cams are not timed correctly, you could hit something hard when rotating the crank. That wont hurt anything as long as you rotate by hand. What you are hitting in that case is a valve not the cct.

[The_big_dill]

Originally Posted by n4mwd

When you are applying pressure on the CCT mechanism, the crank should rotate normally. When the internal CCT is broken, sometimes it will rub the clutch basket which can be felt when the crank is turned.

Also, if the cams are not timed correctly, you could hit something hard when rotating the crank. That wont hurt anything as long as you rotate by hand. What you are hitting in that case is a valve not the cct.

I looked at my cam shafts just not and counter 25 links between the "EX" on the exhaust cam shaft and the "IN" on the intake came shaft. Based on the service manual, i should be able to count 33... The thing is though, the engine has been running like this for a long time and when i spun the crankshaft while applying pressure to the tensioner, i did not feel any interference (valves hitting piston).

Am i checking the timing wrong?

[n4mwd]

Originally Posted by The_big_dill

I looked at my cam shafts just not and counter 25 links between the "EX" on the exhaust cam shaft and the "IN" on the intake came shaft. Based on the service manual, i should be able to count 33... The thing is though, the engine has been running like this for a long time and when i spun the crankshaft while applying pressure to the tensioner, i did not feel any interference (valves hitting piston).

Am i checking the timing wrong?

Yes, you did the timing check wrong. You need the IN and EX lines flat with the top of the head when you do that. You want the chain tight between the two cam sprockets. Also, the crank needs to be on the TDC mark for cylinder 2.

When you put it back together after you fix the CCT, just remember to spin the crank two full turns by hand to make sure its not hitting anything hard. That way, even if the timing is off by a tooth, it wont hurt anything to try to run it that way. That's just a sanity check.

[The_big_dill]

Originally Posted by n4mwd

Yes, you did the timing check wrong. You need the IN and EX lines flat with the top of the head when you do that. You want the chain tight between the two cam sprockets. Also, the crank needs to be on the TDC mark for cylinder 2.

When you put it back together after you fix the CCT, just remember to spin the crank two full turns by hand to make sure its not hitting anything hard. That way, even if the timing is off by a tooth, it wont hurt anything to try to run it that way. That's just a sanity check.

It isn't like that at the moment, but im still not hitting any valves. I am just concerned that some previous owner didn't modify this in their own kinda way...

[n4mwd]

Originally Posted by The_big_dill

It isn't like that at the moment, but im still not hitting any valves. I am just concerned that some previous owner didn't modify this in their own kinda way...

One other thing is that I am referring here to a pregen and how that works while you have a pre-pregen. So there might be a few small differences.

[The_big_dill]

Originally Posted by n4mwd

One other thing is that I am referring here to a pregen and how that works while you have a pre-pregen. So there might be a few small differences.

Good disclaimer

I looked into the 1986-87 manual and it shows the same pic for timing adjustment as the one that motofool supplied earlier in this thread.

Could there be 2 different camshaft positions where the valves are actuated and don't interfere with the piston?

An update for today:

I visited a motorcycle store today and the guy found a replacement lock screw for the CCT that had identical dimensions besides being slightly too long, so he used a hack saw and got it close enough (1 thread longer than the original.

I also got a replacement tensioner spring today and the new one is about 1 mm longer.

Finally, i sprayed 2 quick shots of PB blaster on both sides of that lever and let it sit for 3 hours. Came back later and the tensioner lever moves much smoother than it use to.

[n4mwd]

Originally Posted by The_big_dill

Could there be 2 different camshaft positions where the valves are actuated and don't interfere with the piston?

If the valves are down, the piston will hit them.

I visited a motorcycle store today and the guy found a replacement lock screw for the CCT that had identical dimensions besides being slightly too long, so he used a hack saw and got it close enough (1 thread longer than the original.

I also got a replacement tensioner spring today and the new one is about 1 mm longer.

Finally, i sprayed 2 quick shots of PB blaster on both sides of that lever and let it sit for 3 hours. Came back later and the tensioner lever moves much smoother than it use to.

Sounds good. Don't forget to squirt regular oil on the tensioner hinge once its moving good. Nut buster wont hold up in the heat.

[Motofool]

Originally Posted by The_big_dill

........Could there be 2 different camshaft positions where the valves are actuated and don't interfere with the piston?.........

No, but there is one thing that may make you believe that your cams are out of proper timing:

For each turn of the camshafts, the crankshaft turns twice.

The camshaft sprockets align with the edge of the head as the schematic shows only every second turn of the crankshaft.

It is great that you have improving the pivot and the bolt-retainer.

[The_big_dill]

Originally Posted by Motofool

No, but there is one thing that may make you believe that your cams are out of proper timing:

For each turn of the camshafts, the crankshaft turns twice.

The camshaft sprockets align with the edge of the head as the schematic shows only every second turn of the crankshaft.

It is great that you have improving the pivot and the bolt-retainer.

VERY good point, thanks for mentioning that, i will go check that.

I went to turn the crank and sure enough i feel a huge resistance, until the chain slacked enough for the gears to turn. So the timing was off and i was pushing the valves.

Now to get the timing back in order, do i have to take the camshafts off, or should i just rotate the cams with the chain loose?

[The_big_dill]

Got everything back together with proper torque and order on the camshaft caps and rocker lock nuts.

Timing adjusted as per the service manual. Tested by spinning the crank with a ratchet and no resistance (besides compression).

Put everything back together and it won't start

Turn key, all dash lights come on, choke on, petcock on prime, crank... nothing.

The starter motor is pushing it and it sounds normal, but it just doesn't want to ignite, not even a stumble.

I have a feeling there is no spark. Will check that and compression tomorrow to see if i messed anything up.

One thing i did notice is that after complete assembly, when i turn the engine by hand, every time it comes off a compression stroke (easier to move), i could hear a knock from the bottom end of the engine, somewhere behind the clutch cover.

Any ideas?

[Motofool]

Originally Posted by The_big_dill

...........
Any ideas?

Sorry to read that, Phil

The noise can be anything, probably the clutch basket has worn rubber dampers, which is common but not critical.

I would verify that fuel is filling the bowls up.

[The_big_dill]

Originally Posted by Motofool

Sorry to read that, Phil

The noise can be anything, probably the clutch basket has worn rubber dampers, which is common but not critical.

I would verify that fuel is filling the bowls up.

Thanks for the quick response, after i check spark and compression i will check the bowls.

One other thing i wanted to mention is that i had to take off the camshafts to adjust the timing. I saw the intake side guide and it didn't look like it had anything wrong with it, and the chain still had a little bit of slack on it, however not as much as there use to be.

Putting back the camshaft caps i put some locktight on every bolt and torqued it to 104 in-lbs in the order listed in the manual. I also re-adjusted the valves to the lower tolerance and noticed that the right most intake rocker adjustment screw was maxed out, but the clearance was barely enough to clear the minimum tolerance, i did make sure that the dog ears were around the valve stem and the other end with the screw was in its little "bowl". All other valves were fine.

[n4mwd]

If you post a video on youtube showing the noise, we might be able to help better.

The rockers can get twisted and create a false gap when measuring so watch out for that. Also, the gap should be set to its widest allowable. It gets thinner as it wears. When done, you should be able to jiggle the rockers a little bit. If not, they could be twisted. And of course, you need to inspect all of them visually to make sure the dog ears are intact.

With that done, then I would pull a plug and check to see that its sparking. With the plug out, you can also check the compression. Don't worry about low numbers, compare it to the other cylinder instead. After that, try starting fluid in the carbs. Its hard to get it to work with the airbox and filter on though.

[The_big_dill]

Originally Posted by n4mwd

If you post a video on youtube showing the noise, we might be able to help better.

The rockers can get twisted and create a false gap when measuring so watch out for that. Also, the gap should be set to its widest allowable. It gets thinner as it wears. When done, you should be able to jiggle the rockers a little bit. If not, they could be twisted. And of course, you need to inspect all of them visually to make sure the dog ears are intact.

With that done, then I would pull a plug and check to see that its sparking. With the plug out, you can also check the compression. Don't worry about low numbers, compare it to the other cylinder instead. After that, try starting fluid in the carbs. Its hard to get it to work with the airbox and filter on though.

I don't know if the video will catch such a faint sound, but i will give it a go.

I just came back from the garage and i have spark on both plugs. Plugs had a dark tan colour (on the electrodes), so there isn't any fouling.

I cannot check compression at the moment as my tester doesn't have a small enough piece to thread into the plug hole.

All the rockers had some play in them when the camshaft wasn't engaging them.

One question, is the spark controlled by the flywheel?

The reason i ask is because at one point i had 1 camshaft out so that i can relocate the other shaft and reinstall the one i took out for proper timing. Could i have messed with the spark timing?

I will pull of the head today again and see what i can see, I really don't want to take off the carbs... the airbox boots drive me nuts.

[n4mwd]

The spark is controlled by the flywheel. See the little square tab on the side below? That passes under a pickup coil similar to a tape head. That creates a signal that goes to the ECU which generates a spark every revolution. Both at TDC. One of them is wasted.



So its pretty much impossible to mess up spark timing. The cams are probably correct as well because if they were the source of your problems, you would either have valve-piston collisions or backfiring. Just make sure you set IN and EX with the crank on TDC for cylinder #2 and not #1.



Did you take the heads completely off - exposing the pistons?

If you have it back together now, I don't see the point in removing the heads.

If you have spark, and still can't start, the carbs are the usual culprit. It may or may not be possible to start using starting fluid. I've never been successful doing that, but others say they have. With the bike sitting during repairs, the carbs are probably clogged.

[The_big_dill]

Originally Posted by n4mwd

The spark is controlled by the flywheel. See the little square tab on the side below? That passes under a pickup coil similar to a tape head. That creates a signal that goes to the ECU which generates a spark every revolution. Both at TDC. One of them is wasted.

So its pretty much impossible to mess up spark timing. The cams are probably correct as well because if they were the source of your problems, you would either have valve-piston collisions or backfiring. Just make sure you set IN and EX with the crank on TDC for cylinder #2 and not #1.

Did you take the heads completely off - exposing the pistons?

If you have it back together now, I don't see the point in removing the heads.

If you have spark, and still can't start, the carbs are the usual culprit. It may or may not be possible to start using starting fluid. I've never been successful doing that, but others say they have. With the bike sitting during repairs, the carbs are probably clogged.

Then it must be the carbs or the timing is set for the wrong cylinder TDC, as I didn't even consider which cylinder was at TDC. also, I cannot open the little cover where the 1T and 2T marks are, the thing Is seized.
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[n4mwd]

I've used a big chisel as a screwdriver before. you can use a nickel or anything flat. if you didn't use those marks then you most definitely don't have it set right.

[MR2Aaron]

Originally Posted by n4mwd

I've used a big chisel as a screwdriver before. you can use a nickel or anything flat. if you didn't use those marks then you most definitely don't have it set right.

A bigass washer works pretty well, too. I happened to have one that was *just* the right size to fit into the slot and make really good contact with it.

[The_big_dill]

Last time I used a quarter the coin warped
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[n4mwd]

A steel washer would probably be better. US Nickels are usually tough enough, but not if its stuck.

[The_big_dill]

Originally Posted by n4mwd

A steel washer would probably be better. US Nickels are usually tough enough, but not if its stuck.

I just got it off, a bicycle cone wrench did the trick.

I also got it apart again and when the IN and EX marks are lined up with the cylinder head (33 links apart) the little window shows "2T"

Sooooooo, i guess i got lucky with the timing there.

Are you sure that the "IN" and "EX" are not suppose to line up when the basket shows the "1T" mark?

[The_big_dill]

My $90 torque wrench screwed me over...

Its digital, and i guess the auto shut off feature disables the torque click.



Where can i get more of these bolts??

Also, triple checked that i was on 2T and the EX and IN were at the cylinder head, and the cam lobes for cylinder 2 can be seen here:

[n4mwd]

Its should be on 2T for the cam chain.

For the bolt, just go to the local hardware store and get a new one. Try to get the cheap grade and not a hardened grade. Ideally, order a new one from the dealer. Whatever these things are made of, they obviously snap before they strip the aluminum threads.

Make sure you have your torque wrench on INCH-pounds and not FOOT-pounds when required. I use a $10 torque wrench from Harbor Freight. Has always worked so far.

[The_big_dill]

Originally Posted by n4mwd

Its should be on 2T for the cam chain.

For the bolt, just go to the local hardware store and get a new one. Try to get the cheap grade and not a hardened grade. Ideally, order a new one from the dealer. Whatever these things are made of, they obviously snap before they strip the aluminum threads.

Make sure you have your torque wrench on INCH-pounds and not FOOT-pounds when required. I use a $10 torque wrench from Harbor Freight. Has always worked so far.

Went to the local hardware store and they have something thats too long and too short, i will cut it down as my last resort. However i already placed an order for a new bolt from my local dealer.

My torque wrench can do all, but i use Nm and double checked the numbers.

The reason you get a higher end torque wrench is for precision, not that you would notice anything wrong with it initially. Thats the one tool i want to spend more money on, but then again, thats just me

Anyways, after i replace that bolt, i will clean the carbs and see if it helps. If that doesn't work i don't know what else could be wrong...

One other thing i was thinking about, when looked through the inspection window at the 2T mark, does the horizontal line (relative to the 2T mark) have to be centered on the notch of the casing? And if so, then i think both cams might just be 1 tooth off, is that possible?

[The_big_dill]

Here is a video of what was moving in the engine when i was turning it:

https://skydrive.live.com/redir?resi...FdY-JKcSU6fh8Y

I feel as though there is something moving on the other side as well, such as the clutch basket or whatever is connected to the stator on the other side.

[n4mwd]

Originally Posted by The_big_dill

Here is a video of what was moving in the engine when i was turning it:

https://skydrive.live.com/redir?resi...FdY-JKcSU6fh8Y

I feel as though there is something moving on the other side as well, such as the clutch basket or whatever is connected to the stator on the other side.

A certain amount of play is acceptable, but that seems a bit on the excessive side for a high tolerance engine. That shaft is the main crankshaft and connects to the timing chain on the other side. Maybe @Motofool would know if that amount of play is OK or not.

[The_big_dill]

Originally Posted by n4mwd

A certain amount of play is acceptable, but that seems a bit on the excessive side for a high tolerance engine. That shaft is the main crankshaft and connects to the timing chain on the other side. Maybe @Motofool would know if that amount of play is OK or not.

Would it say in the service manual? Because i can't seem to find it.

[Motofool]

Originally Posted by n4mwd

.........Maybe @Motofool would know if that amount of play is OK or not.

The manual calls for a normal crankshaft side clearance of 0.05 ∼ 0.20 mm (0.002 ∼ 0.008 in.), being the service recommended limit of 0.40 mm (0.016 in.) to ensure performance.

It is hard to appreciate from the video, it seems a little above that.

I would say it is something to expect in an engine that is almost 25 years old, and would apply the old saying: "If it ain't broke, don't fix it."

Any progress with the valves, Phil?

[n4mwd]

Originally Posted by Motofool

I would say it is something to expect in an engine that is almost 25 years old, and would apply the old saying: "If it ain't broke, don't fix it."

That's always good advice. I've seen people on here ruin their whole engine trying to fix something that wasn't really broke.

If the side play is excessive, and you absolutely had to fix it, it would require splitting the engine and replacing the bearings. A complete set of bearings alone runs about $150. Splitting the engine isn't that hard, but its going to take some time. Plus there are other gaskets you need to get/make. Personally, I wouldn't bother if the engine still runs right, but if you ever have to split the engine for another reason, then you should replace the bearings if they are bad.

[The_big_dill]

Originally Posted by Motofool

The manual calls for a normal crankshaft side clearance of 0.05 ∼ 0.20 mm (0.002 ∼ 0.008 in.), being the service recommended limit of 0.40 mm (0.016 in.) to ensure performance.

It is hard to appreciate from the video, it seems a little above that.

I would say it is something to expect in an engine that is almost 25 years old, and would apply the old saying: "If it ain't broke, don't fix it."

Any progress with the valves, Phil?

Thanks for the specs, I would guess its at its service limit. I like your moto, but I also believe in preventive maintenance so I don't like leaving potential problems out.

I took out the camshaft out again to inspect the rocker that was giving me problems, can't see anything wrong with it or the seat though.

I did however remember that after plenty of cranking when originally diagnosing the no start issue, I noticed that the plug electrode was tan and DRY. Which leads me to conclude that the carbs are the issue.
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[The_big_dill]

Took apart carbs again and found one small problem that i forgot about after the first cleaning. The spring that goes in the carb was stepped on at the end and was re-straitened by me to the same length as the other one, but i should replace this. What problems can this cause?

Also, the needle jet that does not thread into anything seems to have trouble staying in place, which way is it suppose to go in?

Finally, the mixture adjustment screw that you tune when the bike is on has complete opposite settings for the 2 carbs. I remember when I was adjusting them, however the bike ran great after this adjustment. Although i never got around to synchronizing the carbs.

[Motofool]

Originally Posted by The_big_dill

......What problems can this cause?

I don't believe that that spring could cause any problem.
I am not sure about that jet.
Both idle screws should be set close from each other in normal conditions.

[n4mwd]

Depends on which spring. I assume you are talking about the diaphragm springs and not the mix springs. The spring pushes against the needle holder and keeps it tight against the bottom of the plastic diaphragm slide. If your needle is loose, then you may have the plastic needle holder in backwards. It fits up inside the spring.

[The_big_dill]

Well, carbs are part way together, need to get a screw driver thin enough to get at the pilot jets.

I also got the replacement bolt and got the timing spot on, torqued everything down and the bolt from the other side snapped this time...

I don't understand whats going on. I set the torque wrench to 12 Nm and it seems to keep wanting to spin. The new bolt did reach the proper torque, but the one on the other side of the long camshaft cap snapped. I am not so lucky this time though, as the bolt snapped inside of the little hollow cylinder that i am guessing is used to position the cap in the right place.

[n4mwd]

Either your bolts are simply bad, or your torque wrench is defective.

I can't tell anything much from your photo, but if its in that hollow pin, then you can just pull the pin out and maybe get a better grip on the broken bolt. A lite grip on some pliers or dykes will pull the pin with no problem.

[The_big_dill]

Originally Posted by n4mwd

Either your bolts are simply bad, or your torque wrench is defective.

I can't tell anything much from your photo, but if its in that hollow pin, then you can just pull the pin out and maybe get a better grip on the broken bolt. A lite grip on some pliers or dykes will pull the pin with no problem.

Its in that guide pin, thanks for the info, i will remove it today.

Honestly, i remember the same thing happening to me with the other bolt. I keep tightening and it doesn't seem to get tighter, then i hear a pop and the bolt just gives out.

The new bolt that i replaced torqued down all the way.

[n4mwd]

Could be that the bolt was stretched previously. I still think its strange that a steel bolt would break rather than strip the aluminum, but I have heard of others with the same problem. Time to order a new bolt.

[The_big_dill]

Originally Posted by n4mwd

Could be that the bolt was stretched previously. I still think its strange that a steel bolt would break rather than strip the aluminum, but I have heard of others with the same problem. Time to order a new bolt.

Already ordered along with a new spring for the carb. But i feel withdrawal from not riding the bike and we had several amazing riding conditions recently

[n4mwd]

Originally Posted by The_big_dill

Already ordered along with a new spring for the carb. But i feel withdrawal from not riding the bike and we had several amazing riding conditions recently

That's why I bought a second bike. That way I always have a backup.

[The_big_dill]

Originally Posted by n4mwd

That's why I bought a second bike. That way I always have a backup.

That is a fantastic idea!

Unfortunately for me, i have a garage that barely fits in a Dodge Caravan, put a bike in there as well and you can't squeeze by...