Dan M

Yes, but in your quest for 40 pages, every post counts.

The BQ dissected. This thread started in May of 07 and ran sporadically for a year to fill 7 & 1/2 pages. It was resurrected in Jan of 09 In the three months since there have been 35+ more pages. How did it get here? Here's some rough posting numbers since January. Since a page is 15 posts. I've only included those with more than a page worth of posts. Ratchet 97 6+pages Dave L 91 6+pages Greg F 87 5+pages Me 60 4 pages Guzzi2go 46 3+pages Raz 29 almost 2 pages Guzzimoto 26 1+pages Skeeve 17 1+pages Seems the BQ is a joint effort.

The GM sensor is not threaded. It is designed to push through a grommet in a plastic air box or duct. I believe RH is securing it in his holder with a set screw.

I'm thinking you have the hot set up so to speak right now. The sensor is designed for air. Thermo paste is adding mass so it may hinder it. I guess that is what experimenting is about. What I really like about all of this is it is lending some credence to early musings from about 30 pages ago when the naysayers were dismissing it as nonsense. Of course they still will.....

You're welcome. Looking at your image I see you did not trim the plastic cage from the bottom of the sensor. I was under the impression you were going to have the thermistor actually in contact with the head. As it appears you are sensing air temp (with an air temp sesnor) inside the holder. Right? If that is how it ended up, I like it. Still an air space as designed to smooth readings but much less lag with the plastic sensor. Am I seeing it right?

Very nice work.

When did I try to tell you that? I believe you are confusing me with others. I made no such claims. I never said a gap was more accurate and I never suggested that adding a heat sink is something I'd do. I simply stated the gap was how it was designed. I must say that I'm assuming that if it made it to production, it followed their design. I also believe that there was a method to their madness. I refuse to accept the notion that they used plastic because it was cheap and spec'd it's length long enough to create an air gap for no particular reason. As far as I've been able to figure it, they did it for the reasons I've stated above and earlier. This is purely my educated guess nothing more or less. I agree that it would make more sense to add fuel at very high temps but we know it doesn't work that way otherwise you would not net the mileage gain by making better contact with the head, especially in hot weather riding.

I just like the idea that a tech topic has gone this far. Even the often volatile cush drive thread only made half as many pages. All this without politics or even one picture of a nipple.

Here's the thing. I've always subscribed to the fact that the best positive contact should be made when sensing temp. That is how everything that I've ever serviced BG (before guzzi) was designed to operate. I run a shop that specializes in emission repair. Accurate fuel injection is kinda my thing. I thought if I could improve fueling on this stab in the dark system, I'd give it a try. Following that train of thought the goo seemed like the right thing to do. Now after experiencing the trouble I am of the thought that the gap is there for a reason. (as talked about at great length 30ish pages ago) The factory map was likely made with the plastic sensor without goo so that is the way I'm leaning now. Sensing the higher temp spikes with this simple system is unnecessary. As I have said, when an air cooled engine is at an extreme temp you want to add fuel not take it away. Running on a hot day and at slow speeds as when stuck in traffic, the head temp soars. If you are sensing the temp spike and mixture is leaned as a result you are adding to the problem with the increased combustion temps. If the mix stays rich the engine will stay cooler. It would follow that there is an advantage in not reading the high temp spikes. (as the air gap accomplishes) My bike ran really well before. I'm returning to the way it was designed. It was fine before the change. Why would I not go back to the scene of the crime? As far as problems experienced by many, it seems like far more have the part throttle, mid rpm, lean misfire to complain about than those who want better economy. But that's just my opinion. Oh, and the holding your finger to the hot pot thing was a joke. (that's what the whistling emoticon was about) I didn't really expect anybody to try it. I guess we shouldn't try to mix in humor.

I'm not too sure about this. If there is an air space between the sensor tip and the head it will never see the temp peaks as it does if there is direct contact (via goo) Next time you have a pot on the stove lift it up and place your finger about 5mm away from the bottom of the hot pot. It will feel pretty hot but not as hot as if you actually touch it. No? Since everybody is experimenting do this with goo in one finger and no goo on another, touch the goo to the pot for a minute and see if that finger gets hotter than the one that has an air space.

Ther are a few ways to look at this. When my bike was completely stock with very low miles it had a lean surge about 4000 rpm. When I changed the mufflers with no other mods the surge was still there and maybe a bit worse. Next I changed the crossover and added a PC3. The surge was eliminated. Over the next two seasons I added pistons and other mods but with a little map tweaking my bike always ran very well. The only time I ever had any trouble was on very hot (90F+) days and I'd get a lean pop at times on throttle opening at low rpm. While doing some off season maintenance I added some copper paste to the cavity in the plastic holder for no other reason other than after reading about it here and it sounded like a valid idea. After that, in any temp above 70F the bike had lean issues. Adding fuel via the PC3 in the problem areas helped but it was never the same as when there was no paste in the holder. So in my case the goo was the last change and it seems, the culprit. I still feel that the engineers were looking to ballpark the temp and didn't want the high temp spikes associated with an air cooled engine factored into the mix. Next step for me anyway is to clean out the paste and see how it runs.

Maybe not Dave, checking guides is pretty easy on the Guzzi especialy if you have access to a compressor and a compression tester. I can walk you through it if you like.

Rather than rererehash all this info and theory and in the process get to 50 or more pages, it would be of advantage to reread this thread starting around page 8. Do you see that there is a connection between running better and using more fuel? Leaning these motors out will often cause issues. On your "the state of tune often does not hold long". I totally agree with Greg. You probably need valve guides. If you can't hold a t-body sync or a valve adjustment, your motor has all the ear marks of loose valve guides.

Hey QM, To spare you from reading 40 pages of stuff here. It has been determined that if your bike has the tendency to run lean, making better temp contact with the head as brass does and as adding paste to the cavity does, the computer senses higher temp and the bike will run even leaner. Disconnecting your sensor causes the computer to think it is very cold so it is adding fuel covering your problem. The trouble is it is too much fuel and your mileage will be bad and you will likely foul spark plugs. Do you still have the plastic holder? If it runs good with it, why change? Hope this helps. edit - only 6 more posts to hit the magic 40

There are parallels SH. In my foggy recollection of the '70s, stoners like Lucas components strived to keep the smoke in albeit not usually successfully.

Motobits foot controls lower the pegs and move them forward some. Coupled with the MPH risers there is a noticable difference in room.

Ha! Fabulous. I've been witness to more than one Lucas part porous enough to let the smoke out. Little did I know they sold replacement smoke. I wonder how much the equipment is to inject it back into the component.

Can't even smell rotting horse meat anymore

And it is appreciated as well as useful. Now watch where it goes from here...

Ahh the tire thread. We're due for more subjective redundancy. Wait, I think I'll start an oil thread.

It is odd that you were able to shift between 1 &2. If the spring is broken you should have nothing. Before you remove the side cover try cleaning and lubing the shifter pivot.

Perhaps one of these guys filled the gap with media from a catalytic converter. Pretty much everything else has been tried.

Just a sharp high quality bit to take the head off before you deform, loosen and start spinning it.

From a Peter Egan column if I recall. Great stuff

Spoke with him again today. He was upbeat. I think he'll be around a while longer. Glad to hear he's upbeat.