Need a Guzzi Doc

[Guest whart]

So, yes, i am a glutton for punishment, riding this afternoon in the 90 degree plus heat. The bike has had a flat spot/misfire at around 2500 rpm since i got it back from the dealer with the staintunes/stucchi/pc, but i usually ride right over that, with the occasional misfire. Today, after about an hour of vigorous riding (but no redlining, i'm still breaking it in), the bike balked and wouldn't start smoothly after a cigarette break. When i finally got it running, i limped it home, no power, would stall at lower rpms, and was humphing, coughrumping, and bofumping all the way home, along with a sound i could only liken to the constant (ie, not tied to rpms) click-click-click of something that i've never noticed before. The dealer had the bike only a few weeks ago to install the mods mentioned above, and to change oil/filter.

Is this somehow associated with hot weather behavior?

Obviously, the dealer gets a call first thing tomorrow, but in the meantime, what's the matta with my poor guzzi?

 

(And, as an additional bonus, I'll tell y'all about my trip to the Barber Museum and my trackday there as well). TIA!

[richard100t]

So, yes, i am a glutton for punishment, riding this afternoon in the 90 degree plus heat. The bike has had a flat spot/misfire at around 2500 rpm since i got it back from the dealer with the staintunes/stucchi/pc, but i usually ride right over that, with the occasional misfire. Today, after about an hour of vigorous riding (but no redlining, i'm still breaking it in), the bike balked and wouldn't start smoothly after a cigarette break. When i finally got it running, i limped it home, no power, would stall at lower rpms, and was humphing, coughrumping, and bofumping all the way home, along with a sound i could only liken to the constant (ie, not tied to rpms) click-click-click of something that i've never noticed before. The dealer had the bike only a few weeks ago to install the mods mentioned above, and to change oil/filter.

Is this somehow associated with hot weather behavior?

Obviously, the dealer gets a call first thing tomorrow, but in the meantime, what's the matta with my poor guzzi?

 

(And, as an additional bonus, I'll tell y'all about my trip to the Barber Museum and my trackday there as well). TIA!

57270[/snapback]

Hmmm sounds like it wanted to vapor lock. Did you get the open airbox mod? I've heard of them actually sucking the heat shield backing off the bottom of the fuel tank. Obviously thats bad for air flow lol. Other than that its probably your pc setting. I'm just guessing though, I'm no mechanic. Your bike is too new for that heat shield to come loose but I'd peek under the tank anyway.

[Baldini]

 

 

Is noise related to road speed? a wheelbearing?

 

What area was noise coming from?

 

Other symptoms do sound like a fuel problem...& w/heat - like Richard says vapour lock? Throttle bodies still in place? No air leaks? Hoses/clamps all there/tight? Headers/balance pipe? Bad fuel, dirt in injector? Was it running on both cylinders? one good one bad? Was valve clearance OK? - broken rocker arm/adj screw? - Plugs/caps OK? Coils? What do plugs show?

 

You're still running it in ...but you already been on track?

 

KB

[Guest whart]

Thanks, guys. Throttle bodies and related appear to be fine; the plug caps are fine, didn't pull the plugs, hard to say if there are any leaks; i don't have the ability to do much more than a visual inspection at this point. Dealer has been alerted. I was curious to know whether, apart from mechanical possibilties, the heat could have made the pc go haywire....

Anyway, i'll report back with the prognosis. Just hoping there was something obvious, like "Oh, yeah, every '04 Nero Corsa does this at the 1,000 mile mark when the temp is over 90 degrees F."

 

As to the track, didn't track the bike. I got to drive the Carrera GT- 606 hp, very light and tight- on the Barber track under the instruction/supervision of Hurley Haywood. What an amazing car, probably the best i've driven. The museum there is well worth a visit: a thousand plus bikes, easily half of that on display, stuff going back to the first days of the 20th century. Vertical collections of Guzzi, MV Agusta, Ducati, etc. spanning the entire production of these companies; rare bikes, like the Britten, collectibles like the ss100 Brough, obscure bikes like the Pierce. No matter what your interest in motorcycles (or even if you have none), this place is a spectacular way to spend time: i think a large portion of Barber's collection comprised the Guggenheim show, and the restoration shops alone would make you cry with delight. Highly recommended, particularly if you can get some track time there while you visit- the track is state of the art, and quite beautiful.

[al_roethlisberger]

Not sure on your problem, but it shouldn't be "vapor lock" as that is an 00-02 model issue. The 03+ bikes have the fuel system internal to the tank, and as far as I know, no one has reported "vapor lock" type symptoms on any in-tank equipped bikes.

 

I would check the valve lash.

 

This issue always comes up in the heat of Summer, and for many bikes, it is simply that the valve lash as set from the factory for North America is too tight once the bike is good and hot. All theories are that this setting was to meet EPA noise regs, but who really knows.

 

All we do know, is if you set the valves to "world" or "raceco" spec lash, the bike will idle and run like a champ even if hot. With the old settings, the valve lash would close up, and the engine didn't want to tick over once hot.

 

This may not be your problem, but is something to check and generally keep in your hip pocket.

 

al

[Guest whart]

So, the problem and solution turned out to be pretty mundane (thankfully). Turns out the the hose clamps on what i would call an input or intake manifold were loose- i'm told by the dealer that this is not uncommon- and a loss of vacuum occurred. The clamps were retightened, and bada-bing. (They also retuned the pc and the bike now doesn't stumble in the 2500-3000 rpm range).

I rode my pimp harley up the dealers- about 40 miles, mostly B roads with some lovely twisties in Conn. Rode the Guzzi back. The difference between the bikes is night and day. The harley (a trick V-Rod) sits low, and is long and heavy; not a confidence inspiring bike to lean, but you can really pour on power. I wish I could use that motor in a smaller, more lithe bike. The Guzzi sits comparatively high, and is a little more "touchy" on the throttle/clutch interplay than the harley (but still nowhere near as twitchy as my old 750 Ducati Monster). When i first got going on the Guzzi, i was riding it 'harley' style; far less lean and slower entry speeds into corners; however, as i got going, it began to come back to me that this bike can actually handle. By the time i got to the Tappan Zee Bridge, not far from home, i was riding almost like a hooligan!

Thanks for the input gents. Another bike may be on its way to me in the endless search for bike perfection, but i'll wait until it is in my hands. In the meantime, the Harley is for sale and the Guzzi is the current bike of choice.

[al_roethlisberger]

...glad to hear that was the problem, and yes it is relatively common for those boots on the throttle bodies to come loose.

 

On a similar note, this is also an area(the boots) one should inspect yearly for cracks, as they not only pop off every so often, but the rubber can crack with age/heat and leak that way as well.

 

Good to hear it was an easy fix