Valve Springs

So before I ordered my parts to rollerize my 09 GRiSO, I poured over all the info I could find.
Pete's idea to use the newer intake valve springs (B013517) sounded like a great idea. I got
my "A"kits, along with everything needed to convert to late style rocker covers. After changing
the 2 springs in the left head I decided to measure the new springs vs old. (Why do I torture myself!)
Wire diameter and number of coils were identical, but overall length was different. the new ones
were .045 in. shorter! That's about 2 shim thicknesses from what I've found elsewhere. Anyone else running
these springs successfully? Or is shimming standard practice? Or is valve float not really an issue?

Why the change? Who knows? Personally I just tend to do it by the book and use the shims.

As for valve float? Well the whole idea of using the beehive springs was to obviate the need for a second spring to combat float issues but unfortunately it would seem that at a certain rpm float still occurs, hence the delamination issues on the flat tappets. One of the reasons I think that some of those German kits that go to twin springs are silly is because, by the look of them, the twin spring set up will substantially increase seating pressure. When you’re using really thin stemmed valves with long, exposed, necks this would seem to me to be a recipe for a disaster just waiting to happen. It will also sap a fair bit of energy so it would seem a bit self defeating.

Each to their own though.

I guess I'll order the shims and seals and run my original "long" springs.
I'm waiting for head gaskets anyway. At least I'll be able to sleep at night.
The good news is the springs were only $3 each, maybe my wife can use them
for earrings

If you’d like to send ‘em to me I can actually do a comparison test using the spring tester at my local engine shop.

Pete

when I rollerised my mate's 2008 Stelvio, we decided to use the new springs on the intake valves only.

He has since made multiple long trips (over a thousand km each) and he is a very experience and aggressive ride, the engine will see more red lines in a month than mine in 10 years. So far so good.

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Pete Roper wrote:

Why the change? Who knows? Personally I just tend to do it by the book and use the shims.

As for valve float? Well the whole idea of using the beehive springs was to obviate the need for a second spring to combat float issues but unfortunately it would seem that at a certain rpm float still occurs, hence the delamination issues on the flat tappets. One of the reasons I think that some of those German kits that go to twin springs are silly is because, by the look of them, the twin spring set up will substantially increase seating pressure. When you’re using really thin stemmed valves with long, exposed, necks this would seem to me to be a recipe for a disaster just waiting to happen. It will also sap a fair bit of energy so it would seem a bit self defeating.

Each to their own though.

Initially I was planning to replace ALL eight springs to the new B013517 spring for my GRiSO and bought more B013517 than I needed

Now I am a little more inclined towards the shim method, probably 51% vs 49%

If I decided the shimming method when I rollerise mine, I will give out the B013517 to those who need it

Phang wrote:

Initially I was planning to replace ALL eight springs to the new B013517 spring for my GRiSO and bought more B013517 than I needed

Now I am a little more inclined towards the shim method, probably 51% vs 49%

If I decided the shimming method when I rollerise mine, I will give out the B013517 to those who need it

Hey Phang, I see you are still holding out on the rollerise upgrade Are the flatties still going strong?

Pete Roper wrote:

If you’d like to send ‘em to me I can actually do a comparison test using the spring tester at my local engine shop.

Pete

Thanks for the offer, but I ordered shims and seals last night. I don't think it's worth shipping $12 worth of springs
halfway 'round the world. A friend of mine makes coil springs, for car and truck suspension, nothing as small as these.
I asked him about them and he said with the same diameter wire, same number of coils and less relaxed height, that,
unless they are a dramatically different alloy, they are most likely to give less seating force. I didn't mention the orange
paint stripe. maybe that's what makes them stronger .

Quote :

I didn't mention the orange
paint stripe. maybe that's what makes them stronger .
 

That's what makes them go faster!

[quote="Phang"]when I rollerised my mate's 2008 Stelvio, we decided to use the new springs on the intake valves only.

He has since made multiple long trips (over a thousand km each) and he is a very experience and aggressive ride, the engine will see more red lines in a month than mine in 10 years. So far so good.

Good to know, I suspect that either way is adequate, but have no way to know. I'm going to shim mine for my own peace of mind,
obviously a proven method.

Thanks to all for the input!

Guzzi Cat wrote:

Phang wrote:

Initially I was planning to replace ALL eight springs to the new B013517 spring for my GRiSO and bought more B013517 than I needed

Now I am a little more inclined towards the shim method, probably 51% vs 49%

If I decided the shimming method when I rollerise mine, I will give out the B013517 to those who need it

Hey Phang, I see you are still holding out on the rollerise upgrade    Are the flatties still going strong?

I didn't ride the GRiSO since 2013 due to some hiccup in life, will rollerise it and put myself back in the saddle soon

Patlikestolean wrote:

Phang wrote:

when I rollerised my mate's 2008 Stelvio, we decided to use the new springs on the intake valves only.

He has since made multiple long trips (over a thousand km each) and he is a very experience and aggressive ride, the engine will see more red lines in a month than mine in 10 years. So far so good.

Good to know, I suspect that either way is adequate, but have no way to know. I'm going to shim mine for my own peace of mind,
obviously a proven method.

Thanks to all for the input!

I thought the same too, I am 1% more incline toward the shimming of old spring just because it is a factory recommendation. Also, when the roller kit is available for upgrading, Guzzi should have the new valve spring on the assembly line. Why they include the shims in the kit but not the new valve spring is a mystery. It could be they ordered too much shims from the supplier and wanted to get rid of it