Timing Gear set

[docc]

Joe replied to my email immediately and offered considerable additional information that I will try and post later. I believe much of this has been included in Lucky Phil's installation thread.

Joe did say there are Daytona and V7 gear runs ahead of the V11, so ours will probably be by the end of the year. The cost of £675 UK Pounds is, today,  $924USD  ($1258AUD)  including shipping (to the USA).

[docc]

CORRECTION! I've edited my post to show that Joe is hoping to have the V11 gears done "by the end of the year."  (What I posted previously was my misread.)

[Pressureangle]

18 hours ago, Lucky Phil said:

You're never in a situation where the cam chain loads are reversing, it's more or less load situation but always in the same direction under normal running conditions.

 

 

I'm 99% in accord with this, *but* there is that 1%. I've attached a photo of a Camshaft for illustration. On a big block Guzzi, all four cam lobes are on the same side of the cam. A compressed valve spring returns all of the energy input on the opening ramp back into the rotation of the camshaft on the closing ramp, minus heat losses through friction; on the ramps where a valve is closing at the same time another begins to open, the opening ramp 'catches' the closing rotational forces and *probably* cancels them. On the other side of the cam, though, there are two closing ramps with no opposing opening ramps to prevent them rotating the camshaft into whatever slack there may be in the chain, or perhaps overcoming the weak stock tensioner. Worse, they close at the same time doubling the effect. I believe that's the source of the spark scatter at idle, and I won't assert but remain open to the possibility that the ~3k rpm dip may be some function of chain slack and resonant property stack in the components. 

 

[GuzziMoto]

I agree with Pressureangle.

Most of the source of "play" in the cam chain drive is a result not of what the throttle position is or whether or not it is under load. It is because of the valve springs. When a cam is opening a valve spring it is "under load". And that load is in one direction, the valve spring is providing resistance to the cams rotation. Once the valve is opening and begins to close, the load on the cam chain is now in the other direction as the cam is now trying to spin faster than the engine because the valve spring is now pushing on the cam in the other direction of rotation.

This dance gets even more complicated when you have multiple valves being opened and closed at the same time. Valves and valve springs make for varying forces through a cam shafts rotation. Those varying forces means the energy required to spin the cam changes as the motor spins. At times the cam is trying to go slower than the motor is, so the load on the cam chain is in one direction. But at other times the cam is actually trying to spin faster than the motor is spinning so the load on the cam chain is in the other direction.

[Tomchri]

And the correct answer is  

Cheers Tom.

[guzzler]

7 hours ago, docc said:

Joe replied to my email immediately and offered considerable additional information that I will try and post later. I believe much of this has been included in Lucky Phil's installation thread.

Joe did say there are Daytona and V7 gear runs ahead of the V11, so ours will probably be by the end of the year. The cost of £675 UK Pounds is, today,  $924USD  ($1258AUD)  including shipping (to the USA).

Thanks Doc 

Guzzler

[guzzler]

12 hours ago, pete roper said:

Well, you'd go to a currency converter on the interwebs and ask. ???

And the currency converter will tell me...

I need these gears and this and that but not the other??

And it'll be this much.

Sorry I asked 

[docc]

19 minutes ago, guzzler said:

And the currency converter will tell me...

I need these gears and this and that but not the other??

And it'll be this much.

Sorry I asked 

I didn't check more than one currency converter when I posted the values above.  As it changes continually, it is only an estimate until the actual exchange occurs. An email to Joe will tell you if shipping to Australia differs from the US.

Joe described other issues that may need attention on the installation. He gave me permission to post his comments, and I will likely do so this evening. Again, I am pretty sure these are the same matters so carefully detailed by Luck Phil having to do with the cam bush and the oil pump bearings:

 

[guzzler]

5 minutes ago, docc said:

I didn't check more than one currency converter when I posted the values above.  As it changes continually, it is only an estimate until the actual exchange occurs. An email to Joe will tell you if shipping to Australia differs from the US.

Joe described other issues that may need attention on the installation. He gave me permission to post his comments, and I will likely do so this evening. Again, I am pretty sure these are the same matters so carefully detailed by Luck Phil having to do with the cam bush and the oil pump bearings:

 

Thanks again Doc

I was just after a rough idea of cost, nothing exact.

Not knowing what parts required ( just gears or blah blah also needed ) means no idea of actual cost!

Wouldn't mind doing this on mine down the track as this bike is a keeper eh.

Cheers Guzzler  

[pete roper]

51 minutes ago, guzzler said:

And the currency converter will tell me...

I need these gears and this and that but not the other??

And it'll be this much.

Sorry I asked 

The cost in £ was quoted above. Chucking £'s to $AU in the currency converter will tell you roughly what the cost will be in $AU. I thought that was what you were wanting to know?

You'll also need a timing chest gasket and front seal and o-ring.

[docc]

I am seeing there are likely some other costs to include: a cam bush with the additional oil reliefs, fresh seals, and perhaps oil pump bearings depending on the accumulated miles/kays.

Here is a reply from Joe Caruso regarding the current availability and advice regarding his timing gears for the V11 Moto Guzzi. (Posted here with his permission.):

 

Hi Docc

Thank you for the email and comments regarding Timing Gears for your V11 it is appreciated.

It has been a very interesting learning curve getting the gears made for the various models and there is more to it than meets the eye so i really can understand why no one else bothers as it is very easy to get it wrong especially regarding the tooth clearances.

I looked into first getting them made as i wanted steel straight cut for all my own bikes which are all 70s Guzzis  v7 sport  lm1 and t3 and because i previously had personal very bad experiences with the aftermarket Aluminium gears that were available at the time.

The Timing Gears are all made to order in batches and do take a long time to get them made.

The Gear Manufacturer has only just started working again after a long closure due to the Covid situation and so is very busy and also has a back log of work from previous orders.

I have 4 valve Daytona models to make next and then V7 so it will be later in the year before anything might be ready.

The Total current price for 1 x set of V 11 Steel straight cut Timing Gears, including Tracked Postage to USA, is £675.00 UK pounds .

Out of interest The combined weight of the new 3 x Steel Gears is about the same if not a bit lighter than the combined weight of the 3 x Chain Sprockets and Timing chain that you are removing.

_____________________________________________________________________________________

The other important items to check before fitting the Timing Gears is the Camshaft Thrust Flange as in the photos attached. As it wears the Camshaft Gear moves closer to the pick up sensor.

Depending on the mileage of your bike then If your Flange has worn a ridge as in the second photo attached then you might possibly have too much Camshaft end float. They should be flat and measure 7.0 mm thick when new. If yours is within measurement and Flat you could add the  3 x oil cutouts in yourself to your existing flange and i could send a sketch with measurements. The new CNC replacements have 3 x oil cut outs and give better lubrication to reduce wear in this area and so these wear a lot better and If required these cost £90 each. These were fitted by the Factory as standard on some later models like the V11 and Daytona.

The Oil Pump Bearings also need to be checked to be in good condition so the pump Timing gear runs true

There is no deposit required or any payment until the gears are all ready and with me and i will update you nearer the time but you are on the next V11 order for sure.

Payment by Bank Transfer is probably the best and cheapest when the time comes because if Payment is made by Paypal  i would have to pass the Paypal charges on which are quite high.

Thanks for the order

Best Regards

Joe

[docc]

The Camshaft Thrust Flange and the desirable relief cuts are discussed in Lucky Phil's "Joe caruso timing gear install" thread.

I am unclear if any of the relief cut Camshaft Thrust Flanges were fitted to any V11 motors?

[Lucky Phil]

3 hours ago, GuzziMoto said:

I agree with Pressureangle.

Most of the source of "play" in the cam chain drive is a result not of what the throttle position is or whether or not it is under load. It is because of the valve springs. When a cam is opening a valve spring it is "under load". And that load is in one direction, the valve spring is providing resistance to the cams rotation. Once the valve is opening and begins to close, the load on the cam chain is now in the other direction as the cam is now trying to spin faster than the engine because the valve spring is now pushing on the cam in the other direction of rotation.

This dance gets even more complicated when you have multiple valves being opened and closed at the same time. Valves and valve springs make for varying forces through a cam shafts rotation. Those varying forces means the energy required to spin the cam changes as the motor spins. At times the cam is trying to go slower than the motor is, so the load on the cam chain is in one direction. But at other times the cam is actually trying to spin faster than the motor is spinning so the load on the cam chain is in the other direction.

Yes I'm aware of the this and it's all largely correct, the valve spring returns SOME of its potential energy back to the camshaft after it's compressed but it's a matter or proportion. From memory it can only return around 80% or maybe less on average due to friction, and other dynamic losses such as having the task of reversing the valves acceleration and pulling the valve back onto its seat so the net result is still not a reversal it's only a lessening of torque in the same direction. There is no perpetual motion machine you don't get all the energy back at any point so the net result is always an input to a greater or lesser degree which keeps the force in one direction to a greater or lesser degree. A multi valve/cylinder engine with more lobes smooths this sine wave energy action as does greater rpm.

If it was some sort of single cam lobe mechanism with little or no frictional losses and little work to do I might be convinced but for a typical engine running in typical circumstances I don't think so.

I think I dispelled the theory of the cam drive and wear/play and inadequacies/wear/spring fatigue in the tensioner causing the hiccupping when I went to the gear driven cams. It made no difference at all I'm disappointed to say, it still hiccupped as before in the same particular circumstances.

Ciao 

[docc]

Here are the two images Joe Caruso sent me relative to this comments about the Camshaft Thrust Flange and its potential wear:

"The other important items to check before fitting the Timing Gears is the Camshaft Thrust Flange as in the photos attached. As it wears the Camshaft Gear moves closer to the pick up sensor.

Depending on the mileage of your bike then If your Flange has worn a ridge as in the second photo attached then you might possibly have too much Camshaft end float .

They should be flat and measure 7.0 mm thick when new. If yours is within measurement and Flat you could add the  3 x oil cutouts in yourself to your existing flange and i could send a sketch with measurements.

The new CNC replacements have 3 x oil cut outs and give better lubrication to reduce wear in this area and so these wear a lot better and If required these cost £90 each. These were fitted by the Factory as standard on some later models like the V11 and Daytona."

[GuzziMoto]

14 hours ago, Lucky Phil said:

Yes I'm aware of the this and it's all largely correct, the valve spring returns SOME of its potential energy back to the camshaft after it's compressed but it's a matter or proportion. From memory it can only return around 80% or maybe less on average due to friction, and other dynamic losses such as having the task of reversing the valves acceleration and pulling the valve back onto its seat so the net result is still not a reversal it's only a lessening of torque in the same direction. There is no perpetual motion machine you don't get all the energy back at any point so the net result is always an input to a greater or lesser degree which keeps the force in one direction to a greater or lesser degree. A multi valve/cylinder engine with more lobes smooths this sine wave energy action as does greater rpm.

If it was some sort of single cam lobe mechanism with little or no frictional losses and little work to do I might be convinced but for a typical engine running in typical circumstances I don't think so.

I think I dispelled the theory of the cam drive and wear/play and inadequacies/wear/spring fatigue in the tensioner causing the hiccupping when I went to the gear driven cams. It made no difference at all I'm disappointed to say, it still hiccupped as before in the same particular circumstances.

Ciao 

I am not saying anything about what causes the hiccup.

I am just pointing out that throttle position, engine load, and whether you are accelerating or decelerating have little to do with cam chain tension. The cam drive is not in that transfer of power path.