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FBF high compression pistons


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Does anyone have instructions on how to install FBF high compression pistons. I bought them on EBAY but they did not come with intructions. If you have a set of instructions, please email them to me at hgravelpha@aol.com or fax to 562-463-1336.

 

How hard was it to install? How long did it take? Any tricks that you had to do to make it fit? Do I have to do anything after the installation - timing - adjustments

 

This a mod that I really wanted to do for years, so please don't spoil it for me with negative remarks.

 

Oh yeah, my bike is a 2001 V11.

 

Thanks,

 

Thang

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The rings have a top and bottom. I forget which is which, but you should be able to tell by comparing to the stock piston and rings. I want to say the rounded edge of the ring goes up.

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Sorry but I have not installed anything like this in my bike. I have however considered doing it in the past so, if you don't mind, I would very much like to hear your impressions of the mod. In particular, does it make your engine ping, do you notice performance gains/losses in the low-end, midrange, or high end of your engines power band? There has been much debate on this board regarding the benefits/wisdom of this mod. I have steered away from it myself but not ruled it out completely.

 

Any input after you are done is appreciated.

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I installed a set on the V11 of former site member Enzo/Capt. Nemo. He raved about it adding gains everywhere. He is notoriously full of shit, though, so I do not know what to believe.

So he still has his Hayabusa eating V11 with the leather HD tool pouch?

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Surprisingly, Enzo is not full of shit on this particular discussion- as you can see from my dyno graph there are gains over 75% of the rev range for both power and torque, and it is this extra shove that makes the bike feel more powerful, although peak power remains the same.

 

By all means fit the FBFs if you want to enhance your V11, but if you want something really fast buy a Ducati.

 

Mal helped fit mine (I made the tea!)- I vaguely remember the circlip on the gudgeon pin being very fiddly but apart from that it all went smoothly, as Greg says its just a straight swap.

 

DynorunV11.jpg

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The rings have a top and bottom. I forget which is which, but you should be able to tell by comparing to the stock piston and rings. I want to say the rounded edge of the ring goes up.

 

 

Couple of thoughts.

The rings should have a stamping mark on them. Usually a small circle or dot. The mark should be up.

Be sure to clean any carbon ridge from the top of the bore. If the new rings pass higher than the old you don't want them to run into it. A very slight hone to break the glaze is a good idea. DO NOT GO THROUGH THE COATING. A ball hone works good for this.

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WHile it could be argued that the high compression pistons may cause detonation due to the raised compression ratio, it could also be argued that they may reduce detonation due to the increased squish area improving turbulence in the combustion chamber. I would not be suprised to find that the net result is a wash.

What is it about todays fuels that you think is worse then fuels of old when it comes to detonation?

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So he still has his Hayabusa eating V11 with the leather HD tool pouch?

 

 

As I said, he's notoriously full of shit, so who knows? He says he still has it, but it's in storage somewhere so I can't grab back the carbon-fiber fairing he stole from me. He grew disillusioned with his V11 when he finally realized that it wasn't a fluke that my Eldo with cast-iron touring tires could leave his "fastest Guzzi on the West Coast" with race rubber for dead on any twisty road. Then, he bought an RC-51 and did a few track days on it. then, he sold that and now "street races" a Morphous scooter. He doesn't show his face much in places I go.

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As I said, he's notoriously full of shit, so who knows? He says he still has it, but it's in storage somewhere so I can't grab back the carbon-fiber fairing he stole from me. He grew disillusioned with his V11 when he finally realized that it wasn't a fluke that my Eldo with cast-iron touring tires could leave his "fastest Guzzi on the West Coast" with race rubber for dead on any twisty road. Then, he bought an RC-51 and did a few track days on it. then, he sold that and now "street races" a Morphous scooter. He doesn't show his face much in places I go.

 

 

He is special isn't he. I remember a few yrs ago I spotted him [or should I say I spotted his bike, perfect for those color blind] at the Vashon TT, resplendently parked at a corner so everyone could see him. He was sitting there revving his bike up, without his helmet on, just revving it up and looking at everyone, a real attention whore we all thought. Didn't know he would be stupid enough to steal from the only Guzzi shop worth visiting in the PNW. That's ok, my opinion of him can't get any lower.

Steve

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What is it about todays fuels that you think is worse then fuels of old when it comes to detonation?

 

Well let's see. When I was pumping Sunoco 260 back in '79 at my part time job it was rated at 106 octane. I think the octane rating might just have something to do with detonation. Unleaded fuels have a lower octane rating primarily because of the absence of lead. In addition today's pump gas may contain oxygenates and/or alcohol. I suppose you could argue that good combustion chamber design, piston dome shape, valve layout, etc. can alleviate some of the effects of crappy gas, but I think most manufacturers have known for a while that high cylinder pressure and modern fuels are a recipe for disaster.

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