CCT conversion

[WMarshy]

Im going to go ahead and pull the cams as there is definitely a resistance trying to turn the motor clockwise now. I can't even get it back the the T mark to check the dots on the cams.

Plan is to remove the CCT then slowly loosen the cam cap nuts untill I can remove the cams. Any cautions about keeping the chain on the crank or is there a way to make sure its on the crank before I go putting everything back together? Thanks for the tips sorry for jacking your thread James.

[bikerphil]

With the valve cover off, you could look down the cam chain tunnel with a flashlight and you'll be able to see if the chain is sitting right.

[James England]

Thanks for the tips sorry for jacking your thread James.

You're wlecome! It doesn't matter if the chain disengages from the teeth on the crankshaft when you loosen the cams but it has to sit right when you put it back together. As Phil said to do, I shone a torch down the tunnel to be sure it was on the teeth.

I found it easier to get everything lined up by not putting the top chain guide in at first. It slips in easily enough afterwards.For some reason, I got everytning lined up and then it all went out of sync when I got the camshafts back down, so I had to start again. I think it was due to the fact that one of the cams is trying to press the valve as you try to line everything up.

[WMarshy]

... For some reason, I got everytning lined up and then it all went out of sync when I got the camshafts back down, so I had to start again. I think it was due to the fact that one of the cams is trying to press the valve as you try to line everything up.

Yeah I see what you mean, I have the engine on the T mark, the cams are in but not bolted down and have the dots facing up, just like the manual says... The cam chain is on both sprockets which are unbolted from the cams. Im still a little concerned that Im doing it right though because #4 cylinder looks nearly TDC and the cams are going to open both intake and exhaust valves as I torque down the caps. The manual says to torque all the caps then use a wrench to align the dots with the arrow on the #3 cap, then install the sprockets... DOES ALL THIS SOUND RIGHT? I don't wanna F somethin up!

[natemoen]

When lined up #1 should be on TDC Compression stroke, and that would put #4 on TDC Exhaust stroke and the exhaust valve should be on its way to closing and the intake valve should be on its way open.

[James England]

Yeah I see what you mean, I have the engine on the T mark, the cams are in but not bolted down and have the dots facing up, just like the manual says... The cam chain is on both sprockets which are unbolted from the cams. Im still a little concerned that Im doing it right though because #4 cylinder looks nearly TDC and the cams are going to open both intake and exhaust valves as I torque down the caps. The manual says to torque all the caps then use a wrench to align the dots with the arrow on the #3 cap, then install the sprockets... DOES ALL THIS SOUND RIGHT? I don't wanna F somethin up!

It sounds right to me. T mark lined up on the pointer. Dots on both camshafts next to the arrows on their respective caps. That means everything is lined up as it should be. As Nathan said, one valve is closing, the other opening.... they're not going to hit each other.

When it comes to bolting the sprockets back onto the camshafts, I found it helped to have the bike engaged in first gear. Otherwise, I found the crankshaft was all too ready to rotate at the merest hint of fiddling with the chain. I engaged first gear, having removed all the spark plugs and then jiggled the rear wheel until the T was lined up.

You have to make sure that the length of chain opposite the CCT side has no slack. Get the chain on the crankshaft sprocket properly and check with a flashlight..pull the chain up tightly over the inlet sprocket and then bolt the sprocket on to the camshaft without moving the camshaft (you may need to move it a teeny little bit to get the bolts lined up with the holes but nothing much). Then the top length of chain needs to be tight between the two sprockets and on the guide before you bolt the exhaust sprocket on. Double check at this point that the T ands the two dots are as they should be. This is the point where mine slipped because the crankshaft spun a bit (before I did the first gear thing). If the back length of chain is tight and the top length tight and the dots and T lined up, then you can rotate the engine slowly clockwise to the C on the timing plate and then put your CCT in place. Tighten the cam chain (if you're using the OEM CCT) manually and then rotate the engine slowly clockwise again until the T lines up again. Triple-check that the dots are next to the arrows and the T is on the pointer. And that the CCT is tightened up (if manual one).

At this point, just being ultra-careful, I would leave the plugs out and rotate the engine clockwise slowly several times to check that the valves open as they should. Then maybe even check the dots and T one last time!!

[jwhughes3]

more noise

After riding today with the conversion and really listening I think there is a tad more noise than before but its so hard to say convincingly that I believe it to be a wash.

Nice peace of mind though.

WHen I pulled my original adjuster and let the adjustment nut go there was only about 1/16" adjustment left in it - the newer one has a longer plunger so should work longer I think.

John

[James England]

I think there is a tad more noise than before but its so hard to say convincingly that I believe it to be a wash.

Breaking our helmet laws here, I went out with no helmet on yesterday, just several hundred yards down the country roads, just to hear the engine.I did this before the CCT conversion too. Like you, I really listened but I think the fact I had to really listen means, if it is actually louder, it can't be by much.... if at all..... difficult to say (a good sign IMO).

Like you say, peace of mind. My old CCT was dented and worn on the face where the bolt engages and it did look like it had slipped back at some point.

[3Phase]

If you've removed the gears from the camshafts, make sure the timing marks on the gears are aligned with the dots on the camshafts and not 180* out.

There are a couple of pictures of the camshaft gear timing marks in the Yamaha manual on page 3-45 but they're not mentioned in the text.


Camshaft sprocket timing marks



Camshaft sprocket timing mark


And there is a note from our friends across the water, with much better pictures of course:-


1L9-12176-00-00: Sprocket, Cam Chain (34t)

Lamric commented on Friday, 18th December 2009:

"Cam sprockets go on with the embossed markings away from the mounting flange and the one with the bump goes toward the dot on the cam"

[DAVINCI]

Well I'll be damned...never gave it any notice. The flat side vs. bumpy side is obvious, but that little bump mark is not so obvious. Being that the mounting holes are 180* apart, how much difference would it make if the bump was positioned 180* out?

[3Phase]

Being that the mounting holes are 180* apart, how much difference would it make if the bump was positioned 180* out?

Honestly: I don't know.

I've always put the gears back with the timing marks lined up but it seems ... worng for Yamaha to put a timing mark on a gear if it's not necessary.

It might cause the camshaft(s) to be slightly out of time and the camshaft dots wouldn't line up with arrows on the bearing caps. I'll pull the cams out of the borked XJ engine I have stashed in the garage and see it if makes any difference one way or the other.

[James England]

When doing mine a couple of weeks ago, I didn't even check those sprocket marks. I just got the camshafts lined up with the arrows on the caps and the crankshaft on the T mark.

Because the holes in the sprockets are exactly 180 degrees apart and directly opposite each other, I'm not sure why it would make any difference if they were completely out. I think it would be important if they were accidentally reversed.... ie completely removed and then twisted through 190 degrees along a vertical axis. But not horizontal....

I've been running mine all the time ( I didn't completely remove the sprockets so can't have twisted them on a vertical axis) and I don't think I'll bother taking it apart again just to check.....

[James England]

And there is a note from our friends across the water, with much better pictures of course:-

I'm curious, Scott...... why the "of course"? Do we have a reputation for good pix?

[motoman]

Never have had to deal with that Scott, but interesting to say the least. Difference 180degrees out MAY be found by counting the sprocket teeth both directions from centerline vertical......and you may have already one that, but JAT.

[3Phase]

I finished checking the marks and I can't see any difference in engine timing. I didn't break out the degree wheel and dial indicator but I don't believe it's necessary to go to that level.

The gears are used in other bikes so they might be used in one of those engines.

Unless your anorak is zipped all the way up and the drawstring on the hood is pulled a little too tight it doesn't matter how you install the gears as long as the bumps face outward, away from the mounting flange on the camshaft.

James: Aside from the amount of work and information that's been put into the benefiscal.co.uk parts lists, almost any picture on the planet is, of course, better than the ones printed in the Yamaha manual!