High Compression Pistons

[Guest ratchethack]

Here in Canada 91 is available everywhere and Petrocan and Chevron have 94 RON. I try to use them whenever possible as there is never a problem with them but 91 works well for me except on hot days when I have sometimes noticed pinging at low rpm and too much throttle. I find that not lugging the motor avoids this.

Hm. 94 RON would go a long way toward solving many problems here.

 

How's y'er Guzzi run on helicopter fuel?

 

Enquiring minds just gotta know!

[big J]

Big J, there are many many things that people do that I will never begin to understand, many of 'em right here on this Forum. As far as I can tell, my Pal's in exactly the same situation now as the previous owner was over 2 years ago when he dumped the bike at his dealer for a pittance after draining a considerable pile of his bank account into it - lots of good money after bad. Both owners got a hard lesson and paid dearly for it for the same reasons and ended up in exactly the same spot. As far as I can tell, this kinda thing happens a lot, and always has. Amazingly enough, this won't likely be the last stop on this train. Is it finally shame and humiliation that eventually overcomes whatever the attraction was in the beginning and eventually inspires a search for greener pastures?

 

And so the cycle continues. . . . .

 

But why not fix it?How hard can it be?Christ,pull the heads off and take a mill file to the piston crowns if you cant afford machining time.If it's just pinking cos of high compression get some acetone and mix it with the petrol.Nail varnish remover worked for me in the past,you dont need much.(and nowadays,I dont varnish my nails )

[helicopterjim R.I.P.]

 

How's y'er Guzzi run on helicopter fuel?

 

Dunno 'bout that one but I know up in Northern BC and Yukon some of the locals like to pilfer barrels of Jet B (40% kerosene and 60% naptha) and mix it 50-50 with pump gas to run in their 2 stroke snowmobiles. They claim it runs much better especially in cold weather. I've not seen or heard of any fueling problems or engine failures from this mixture.

[Guest ratchethack]

BigJ, it ain't my Guzzi and I can't speak for the owner. Like I said before - if it were me who'd bought it instead of my Pal, one way or another, it'd have been out on the road and out of its break-in period 2 years ago. . . . . .

[dlaing]

 

I've witnessed this cycle many many times with many owners of many marques. During the time I've owned my Guzzi, I've seen the identical pattern many more times with Guzzis, including right here on this Forum. Some of these guys, like my Pal with the FBF hi-comp pistons and the previous owner of his Guzzi, never get the Guzzi out of its break-in period - even after years of ownership.

 

Care to name names?

For some reason your buddy is the only one I recall getting in over his head

[luhbo]

BigJ, it ain't my Guzzi and I can't speak for the owner. Like I said before - if it were me who'd bought it instead of my Pal, one way or another, it'd have been out on the road and out of its break-in period 2 years ago. . . . . .

 

Your Pal and again Pal and Pal and Pal and my buddy and my Pal...

 

But somehow neither he nor his bike seems to be touching you in any way. What do you call "Pal" in your language?

 

"Enquiring minds just gotta know! "

 

Hubert

[Guest ratchethack]

Your Pal and again Pal and Pal and Pal and my buddy and my Pal...

 

But somehow neither he nor his bike seems to be touching you in any way. What do you call "Pal" in your language?

 

"Enquiring minds just gotta know! "

 

Hubert

By all means, leave us never allow an enquiring mind to remain parched for lack of nourishment any longer than necessary!

 

Hubert, believe it or not, I have many Pals and Buddies. Some of 'em have Guzzis. Though I don't see some of 'em for months sometimes, we're still Pals. The one in question with the FBF hi-comp pistons in his 2000 Sport is the President of a European Motorcyle Club with over a hundred "unofficial members". I met him at a Guzzi rally a few years ago. I have his business card and a standing invitation to join their weekly meetings, and have been to many meetings and on several of their rides, but haven't been able to make their breakfast meetings lately. I'm on their email list and get all the club info at least once per week. We converse semi-regularly by phone and email. I call him my Pal and vice-versa. Though he doesn't frequent Forums like this, he's a fairly active Guzzista, and meets regularly with Todd Eagan (as mentioned before). They're Pals. Among many other roles and responsibilities having to do with Guzzis, Todd is co-host of GuzziTech.com http://www.guzzitech.com/ and a fairly active promoter of Guzzi events listed on So-CalGuzzi.com http://socal-guzzi.com/PHPBB/viewforum.php?f=1.

 

Would it satisfy your suspicions if I posted a photo of my Pal next to his Guzzi? I don't have one, but I think I could get one eventually. If not, would it satisfy your suspicions if I posted a "man on the streets" interview about his experiences with, and opinions on the benefits and trade-off considerations of FBF hi-comp pistons in a Guzzi? I assure you that he's well-spoken and it's become a real "hot button" topic for him. Posting a comprehensive "interview" with up-to-date photos and direct quotes may take a while, as he doesn't ride the Guzzi very much, as I mentioned. He's been riding a very nice 900S instead. I've been posting his experiences first-hand, directly from his mouth to my ear as he has relayed them in some detail to me face-to-face.

 

As I mentioned Part II, He's put the word out to the club that his Guzzi is for sale to the right buyer. Now If y'er genuinely interested in the potential of purchasing and shipping a beautiful Guzzi green, moderately modified 2000 Sport from California that hasn't yet reached break-in, let me know and I'll pass on his contact information in a PM and you can talk with him personally. He's a great Guy and you might even become Pals. But please don't bother unless you're prepared to demonstrate a sincere interest. Since he's my Pal, I wouldn't want to waste his time with a silly inquiry to verify that he exists or to verify my account of his experience. He's not by any means the only one, Hubert.

[Guest ratchethack]

Care to name names?

For some reason your buddy is the only one I recall getting in over his head

Dave. Are you doubting the existence of Guzzi owners with more enthusiasm for go-faster modifications than experience and/or common sense? The woods 'r full of 'em. For about 3 years now, I've frequented 5 Guzzi boards where they're in a constant state of entering and unceremoniously exiting the regular posts. Though they tend to fade away and disappear with little fanfare, if y'er a regular Forum reader and you pay any attention to it, you can see 'em coming. Many times all you see posted is the initial flurry of great excitement, but don't notice when there's been no follow-up posts. I think of 'em as high probabilities of flashes in the pan followed by failure to achieve ignition.

 

Now I've never said that there's anything WRONG with a properly informed, careful approach to modifying for increased power. It can certainly be done successfully when the right objectives and an informed, experienced approach are brought to bear. The posts here and elsewhere are full of such accounts and many seem very pleased. If they've done a good job, IMHO they've a right to be pleased.

 

To the casual observer, or to one lacking discernment, however, it might appear that there's NO DOWNSIDE and NO RISK involved with chasing higher curves on dyno charts by indiscriminately bolting on all manner of go-faster gear, as if it's as simple as throwing groceries in a cart at y'er local Goofy Mart. This is a common mistake that's well borne out by history and the facts, IMHO. I submit to you that more often than not, chasing horsepower is not done very well by those who either have no experience or understanding of the trade-off considerations, or who simply tend to ignore and dismiss anything "negative" that gets in the way of their childlike excitement of the moment.

 

I've cited the usual scenario point by point. No one I've seen jump on the familiar treadmill unprepared, only to fall off with a new-found education the hard way is any too happy about it after the fact -- and none too enthusiastic about broadcasting their lack of preparation for the lessons they've learned the wrong way. All the happy talk of "free" bolt-on horsepower is often long forgotten by the time a typically uninformed and naive Guzzista gives up their quest of something approaching Eraldo's "no problem" 140 bhp on the dyno. I'm sure you recall your previous contributions to the discussion on Eraldo's most unfortunate - and absolutely absurd, IMHO - sales hype, Dave. To refresh y'er memory, here's the link: http://www.v11lemans.com/forums/index.php?...0&hl=Eraldo These are the very kinds of unqualified claims and common misinformation that seem to launch the silly chasing of pipe dreams that invariably end in disappointment that very few are motivated to post on public Forums.

 

Many here continue to seem entirely unconvinced by the hard-earned, well-qualified statements made by Pro's like Greg and Pete about reasonable expectations and trade-off considerations of chasing power output -- including right here in this thread. Unless I miss my expectations completely, both Pete and Greg have pulled many sets of chestnuts out of the fire spawned by many half-baked attempts to create fire-breathing Jap Bike Killers out of Guzzi's.

 

Are you still in agreement with Eraldo's unsubstantiated claims of 140 bhp "no problem", Dave?

[luhbo]

.... he's a fairly active Guzzista, and meets regularly with Todd Eagan (as mentioned before). They're Pals. ...

 

As long as he's riding under the warm and blessing shine of Todd and GuzziTech all will become well in the end

 

No, just improper kidding. But in fact my question was meant differently. I just thought that if it was my Pal I'd tell him to come over with his bike and we'd sort out the issues it suffers from.

 

Probably just a misinterpretation of buddy and Pal. Sorry for that.

[Guest ratchethack]

I just thought that if it was my Pal I'd tell him to come over with his bike and we'd sort out the issues it suffers from.

I've got a fairly well-equipped home shop, and I'm capable & experienced with of lots of stuff that many of my Guzzi Pals aren't. I've always done 100% of my own moto maintenance on every one of 12 bikes (to date, of which I still own 2), many of which got complete rebuilds &/or resto's. I repeated an offer to my Pal with the FBF hi-comp problems to come over for a Guzzi Clinic session a couple of times. You can lead a horse to water, etc.

Probably just a misinterpretation of buddy and Pal. Sorry for that.

No need to apologize for anything, Hubert. Sometimes it takes a little back-and-forth for meanings to get across - especially when (some) Americans attempt to communicate with other Americans in English! . . . . .

[big J]

As long as he's riding under the warm and blessing shine of Todd and GuzziTech all will become well in the end

 

No, just improper kidding. But in fact my question was meant differently. I just thought that if it was my Pal I'd tell him to come over with his bike and we'd sort out the issues it suffers from.

 

Probably just a misinterpretation of buddy and Pal. Sorry for that.

 

Yeah,me too.I couldn't understand why it wasn't sorted already.Maybe he'd take a couple of weeks to get it done,but no improvement in YEARS??????

 

We must just have different definitions of "pals."

[polebridge]

As you can see from the link in Rachethack's post, I am the member that started a previous thread on this topic. In the end I took the advice of several of the members here and opted NOT to install HC pistons. Instead I installed all bolt on stuff, MG Ti cans, FBF X-pipe, FBF air box kit, and a power commander with custom map done by FBF in PA.

 

I am now getting something like 87 HP and 71 torque at the rear wheel and I am quite satisfied with the results. The bike runs fantastic as modified! I think that the article regarding the full FBF mods (hc pistons, bigger valves etc.) got around 95 HP if I recall. I don't think, for me anyway, that the extra expense of new pistons and values is worth the extra 7-8 HP. At least that is how I feel now. Maybe after I have owned the bike a while and put some miles I it I might change my mind. Maybe not.

 

So...if you haven't already done so, try going the easy route like I did. If you are not satisfied you can always go for the HCs.

 

One more thing. A lot of members here have complained about a ton of intake noise with the air box kits installed. I do not notice any objectionable noise level at all on mine. Am I deaf, do I have this thing installed incorrectly, or is the FBF kit just quite compared to other air box kits out there?

 

Ride safe!

[Guest ratchethack]

I installed all bolt on stuff, MG Ti cans, FBF X-pipe, FBF air box kit, and a power commander with custom map done by FBF in PA.

 

I am now getting something like 87 HP and 71 torque at the rear wheel and I am quite satisfied with the results. The bike runs fantastic as modified! I think that the article regarding the full FBF mods (hc pistons, bigger valves etc.) got around 95 HP if I recall. I don't think, for me anyway, that the extra expense of new pistons and values is worth the extra 7-8 HP. At least that is how I feel now. Maybe after I have owned the bike a while and put some miles I it I might change my mind. Maybe not.

Congrat's Polebridge. Impressive numbers, IMHO. Seems entirely reasonable to me. It's the same config I have with the exception of the open-top airbox. As far as I'm concerned, this is a sensible point in the bang-f'er-the-buck modification progression where you're cost-to-benefit ratio hasn't yet hit sharply diminishing returns. That, and you haven't done anything that would diminish reliability or longevity.

One more thing. A lot of members here have complained about a ton of intake noise with the air box kits installed. I do not notice any objectionable noise level at all on mine. Am I deaf, do I have this thing installed incorrectly, or is the FBF kit just quite compared to other air box kits out there?

I tried an open-top airbox and there was no question about it - it was too excruciating to consider. The stock airbox top went back on immediately. I've noticed that different guys seem to have different thresholds of tolerance for intake-generated sound pressure. I'd be a little careful about the possibility of hearing damage that could be happening below y'er threshold of pain.

 

Ever talk with guys who've logged dozens of cross-continent moto tours? The first thing many of 'em say when you introduce y'erself is, "WHAT?" According to many I've talked with about this, it's the long-term effects on the hearing of wind buffeting inside the helmet without ear protection. It didn't bother them at the time. Wind buffeting doesn't bother me either. I might start using ear plugs on trips myself, starting tomorrow.

[pete roper]

Firstly, Alex, I'm sorry if I seemed to to be having a go at you, (Or anybody else.) It wasn't my intention.

 

Secondly, while I'm sure that there are plenty of people who are using higher comp pistons and are perfectly happy the fact remains that chasing higher CR's by putting a bidder dome on the piston of what is essentially a very primitive 2 valve motor is IMHO not a particularly good choice if you want to chase power and tractability. Unfortunately such designs invariably end up with incomplete scavenge and pockets of end gas that will pollute the incoming charge. This, along with the crap fuel we get nowadays, greatly increases the chance of detonation and all of it's associated problems.

 

There is also the fact that a 2 valve Hemi is not exactly cutting edge in terms of volumetric efficiency so a large part of the benefit of a higher CR is going to be lost, certainly in terms of outright power, at the higher end of the rev range.

 

I'm not saying you shouldn't fit higher CR pistons, (The FBF pistons are I believe Wisecos so they will be a good, light, forging but with a more limited lifespan than some.) although I can assure you that living where I do bumping up the CR is not something I'd be keen to do. All I'd say is that it's probably one of the LAST things I'd think about doing, and only then if I was desperate to chase ponies out of a Guzzi donk. As previously stated buying a 3 year old CBR600 and going to a few track days will give you FAR more bang for your buck and the Guzzi motor is a superb ROAD motor. Certainly it can be tweaked and improved, I simply think that high CR pistons are paddling the canoe up the wrong creek.

 

And finally, one more time!!!!! Get the chassis and suspension set up correctly before you do ANYTHING to the motor. Getting that right is worth seconds a lap at a track day or down you favorite bit of twisty road. Honest!

 

Pete

[Guzzirider]

. I don't think, for me anyway, that the extra expense of new pistons and values is worth the extra 7-8 HP.

 

I think I am the only person here who has measured my bike on the dyno pre and post FBF installation. The interesting thing is that there is absolutely no extra peak horsepower- the extra urge that owners of FBF bikes notice is from an enhanced midrange not extra top end.

 

The important thing here is that if you are chuffed with your bike as is then thats great!