Bad Pinking

[dangerous]

...and the verdict is???

83318[/snapback]

Ohhh yeah sorry, Well the bikes went well on 98 however it was cold and very wet... I have only had problems on very hot days and nailing it in the hills, this ride was flat all the way.

 

Last w/e I had the Guz at the local track, I was wanting to try avgas but was warned off it, so I went for 98 (remember 98 in NZ is imported were as 91/95 is made here and is as shitty as fuel can get)

I mixed a high grade octain booster with it and dont think that it made that much of a differance it should have raised the oct too 100.

However the bike did not pink once, but thats not a good example as I was keepin the poor thing in the high rev range well over were it might pink.

 

This Sunday weather permiting I'm looking at a ride over the local hills, if so Ill try the booster again and I will know if it makes a differance... then I'll report back, again.

[mark.gilmore]

#3: Hemi head. Hemi's are great when you have 4v heads w/ a central sparkplug & great intake tract design for good mixing. They bite when dealing w/ 2v heads with their offset plugs, large valves, and not-so-great intake tracts that don't flow & fill as well as they might... The dual-plugging of the latest iteration of the Guzzi big-block is just a band-aid for this antiquated hemi-head design.

 

Ride on!

74118[/snapback]

 

 

I agree,but dual plugging seems to fix all these problems on old 2valve motors.of corse it wont hurt either

[Guest ratchethack]

One potential cause of ping that I haven't seen mentioned much (anywhere) is contamination of the fuel charge through worn valve guides. Seems to me that without the benefit of valve guide seals, and (to my way of thinking) unusually rapid wear of guides for a motorcycle, with some reports of guides ~1 mm out of round at 30 K miles , this would be a strong candidate as a cause of ping. Since I'm at the point of trying to optimally time a heads-off inspection, any additional knowledge and/or experience on this would be more'n welcome!

 

Also - I understand that it's possible to machine guides to fit seals on these bikes. Any comments on cost-effort/benefits?

 

TIA

[Guest ratchethack]

when I am going up a steep hill in sixth gear at 4000 RPMs and I whack open the throttle, I accellerate initially without pinging, and then ping from about 4500 to 5500 rpms.

But if I I am going up a steep hill in sixth gear at 4500 RPMs and I whack open the throttle, I ping immediately and continue to ping from about 4500 to 5500 rpms.

Dave, maybe this is just me, but I'd NEVER ride my Guzzi this way! Consider that both 5th and 6th gears are overdrive ratios. If you're climbing even a slight incline, you're severely lugging the engine if you're in either of the overdrive ratios and abruptly open the butterflies! As a general rule, I never use either 5th or 6th to climb any incline - no matter how small. In addition to all the factors that contribute to ping, overall, it's a function of the load placed on the engine - not simply throttle opening and RPM. When engine torque is insufficient to very quickly overcome the load asked of it - as would always be the case climbing a steep hill in 6th, of course it will ping in protest!!! Make use of those oh-so-well-spaced lower cogs to "ride around" the ping - ya got a whole box full of 'em!

 

I don't "baby" my engine whatsoever - but I don't abuse it either. Consistent with this, I don't even use 6th unless I'm either on a long downhill, have a strong wind at my back at or above around 80 mph, or are otherwise "loafing" the engine at low throttle openings without much load, and I treat the engine just about the same WRT 5th @ ~70+ mph...

 

BAA, TJM, & YMMV

[helicopterjim R.I.P.]

noticed some bad pinking

 

73757[/snapback]

 

I had some good pinking on my bike once but my wife won't let me take those kind of girls for a ride anymore!!

[badmotogoozer]

There is no bad pinking. It's like pizza... even when it's bad, it's good.

 

Rj

[Skeeve]

#3: Hemi head. Hemi's are great when you have 4v heads w/ a central sparkplug & great intake tract design for good mixing. They bite when dealing w/ 2v heads with their offset plugs, large valves, and not-so-great intake tracts that don't flow & fill as well as they might... The dual-plugging of the latest iteration of the Guzzi big-block is just a band-aid for this antiquated hemi-head design.

I agree,but dual plugging seems to fix all these problems on old 2valve motors.of corse it wont hurt either

83357[/snapback]

 

Kludging the pinging problem by going to dual-plugs is reasonable for a solitary individual since the increased machine operations & extra parts are insignificant concerns on an individual scale; from a production standpoint, it's much more cost-effective to do it right by redesigning the heads & pistons to do the same job with a more efficient burn off one spark plug. Or did you think the H-D 50mpg numbers came about because of their great power/wt ratio?

 

Even dual-plugged, the inefficient chamber design of the Guzzi engine doesn't see those numbers. C'mon, Ricardo told everybody about this 70 years ago; it's time Guzzi kept up!