The definitive guide to Rollerisation

That is the new style earthing tang. It goes under the two bolts that hold the rocker retainer late to the cambox. You discard the earlier tang.

Inlet valves have greater mass, hence the need for the increased seating pressure afforded by the shims.

Pete Roper wrote:

That is the new style earthing tang. It goes under the two bolts that hold the rocker retainer late to the cambox. You discard the earlier tang.

Inlet valves have greater mass, hence the need for the increased seating pressure afforded by the shims.

Thanks for the reply, Pete.

Or maybe you have a something manual to get to know it before work? Or some photos? Video?

Not really. It's pretty straightforward. I did write this years ago.

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Thank you very much. You're a genius, Pete

No! I'm anything but! All I am is someone who has filtered the sugar from the shit.

None of this rocket science. All it needs is an active interest rather than just brushing shit under the carpet to make a quid.....

Is necessary after rollerisation change softweare ECU?

It'll run. Just not very well.

Hello. Today I started repairing my GRiSO timing gear. After dismantling the exhaust system, I saw the following view in the heads



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Does that often happen with these engines? I understand this means replacing the heads?

That's not an actual crack, is it? It's not just a casting mark?

beetle wrote:

That's not an actual crack, is it? It's not just a casting mark?

I think this is a real crack


EDIT: Now I remove second head and I see in inlet and outlet tubes identical damages

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Is possible that in all four tubes been identical cracks??? Is strange

Looks like casting marks to me, but WTF would I know?

I've seen it several times. On the ones I've seen they are cracks. The good news is that they don't seem to cause any further issues. The main one I would of been concerned about would be the exhaust valve seats dropping out but I haven't heard of that ever happening.

In my experience such cracks have occurred principally on engines still running a closed loop map. Is that a relevant factor? I dunno, but if the engine is ridden a lot in closed loop where the AFR is kept deliberately lean the exhaust gasses are going to be hotter and the chance of an expansion related failure is going to be more likely.

Does that theory have legs or am I just talking out of my arse? I've no idea. I'm not a metallurgist.

Pete Roper wrote:

Does that theory have legs or am I just talking out of my arse? I've no idea. I'm not a metallurgist.

Metallurgist?  It sounds to me you're a ventriloquist!  

I suggest using a 90⁰ engineers probe to see if they are cracks or raised casting marks.

From your photogrsphs they don't look dark enough or sharp edged enough to be cracks. So as they seem identical i would assume casting marks. But if s probe or feeler gauge goes into them that proves your point.

lcjohnny wrote:

I suggest using a 90⁰ engineers probe to see if they are cracks or raised casting marks.

From your photogrsphs they don't look dark enough or  sharp edged enough to be cracks. So as they seem identical i would assume casting marks. But if s probe or feeler gauge goes into them that proves your point.

What is 90⁰ engineers probe?

Steel rod with sharp end at 90⁰
May be called a scriber or dental pick

The heads were x-rayed and it turned out that they were not cracked. These are foundry marks.

I have another question: should the right timing chain tensioner insert be mounted with a small hole in the smaller part in some specific way, does it not matter?

Right and left tensioner plungers are different. The valve hole goes towards the reservoir on both.

Pete Roper wrote:

Right and left tensioner plungers are different. The valve hole goes towards the reservoir on both.

Pete - I mean this small hole on tensioner piston


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Yup. It's there to allow oil from the reservoir into the chamber above the valve. If you mean does it have to be aligned in any way other than in the reservoir? No. It'll spin around in service anyway.

With the help of Pete Roper's instructions, I was able to replace the timing tappets on my GRiSO. However, I have another question. The bike is running perfectly just as it was before the repair. It is impossible to discern any difference in any respect. Therefore, is it necessary to change the ECU software, or can I run on the current software? Does it pose a risk of malfunctions?

There’s no need to update the software. There’s been no change to the GRiSO map or software since 2010.

If your bike is currently running the final iteration of the factory maps then you simply need to clear the trims which can be done by pulling the main 30A fuse or disconnecting the battery briefly. If you were running a non factory map or one of the earlier versions from the factory then it should be remapped.

If you want it to run better than it ever has just buy one of Mark's maps and stick it in.

I'm sorry for the naive question, but with what software can you do it in Moto Guzzi? Could I also ask for a user Mark?

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