Throttle Body Balancing

[Cachnutz]

Hey Everyone

My new to me 2011 Norge 8v is in need of a TBS balance
I have purchased the proper cables, and have Guzzidiag

I have a homemade manometer that I was using on a previous bike and I feel it will work again.

My questions
-Where are the air bleeds located?  I have read "Firstly close both of the air bleeds on the throttle bodies" Is that the same port as where to connect meter?
- since I am connecting to some clear tubing, what type of connector is suggested to fit between tube and manifold port? Mine are tightly plugged with an allen key screw. I have heard a brake nipple type fitting?

Im a little confused and dont want to mess it up, any help would be greatly appreciated.
Thanks
Chris

[Tom H]

I tried to quickly find a service manual for you, no go. But did find a parts book maybe that might help:

http://www.thisoldtractor.com/moto_guzzi_misc_spare_parts_catalogs___exploded_parts_diagrams___parts_fiche.html

Pick the one that matches your bike.

I know where the bleed screw is on my EV, just don't know on your bike.

Tom

[Kiwi_Roy]

I would be very cautious before attempting to balance such a late model machine.
You have one of the best Guzzi mechanics on the planet right there in Chilliwack
Unfortunately the Stradavarious site seems to have shut down but you also have a group of Guzzi owners who I'm sure will help you out,

[pete roper]

I'll post some pics when I get the chance but the air bleed screws are inboard and underneath the TB's and require a 5mm Allen key to turn.

Tuning a W5AM Guzzi is so delightfully simple that nobody should be afraid to undertake it as long as they have the correct tools and know what to adjust and what to leave the hell alone!

Pete

[pete roper]

LH air bleed.



RH Air bleed.



Bell crank screw that is used for high speed balance.



'Sacred Screw' that should be sealed with paint and never touched on pain of incendiary underpants!



The ball joints on the linkage rod between the two throttle bodies  also have lock nuts sealed with paint and these should never be touched!

Finally a close up of an air bleed screw. Do NOT over tighten these when closing them or they will snap and then you're buggered!

[Dukedesmo]

I use a Morgan Carbtune to balance the carbs and TBs on my bikes, works very well.


With regards to hose adaptor/fittings you can also get from Morgan and these are good for all types of gauges. They supply either plastic or brass (for permanent installation) both in 5mm and 6mm;  http://www.carbtune.co.uk/carbaccs.html

[tris]

Speaking of Carbtunes. Very good instrument and I balanced my B11 yesterday with mine.

However after I'd finished and was putting the tools away for no particular reason I applied a vaccum (gave it a suck) and then blocked the columns in turn.

I found that one column stayed put and the other decayed away 

Has anyone else experienced this and was it pipe or the column itself?

[Kiwi_Roy]

I have a homemade manometer that I was using on a previous bike and I feel it will work again.

My questions
-Where are the air bleeds located?  I have read "Firstly close both of the air bleeds on the throttle bodies" Is that the same port as where to connect meter?
- since I am connecting to some clear tubing, what type of connector is suggested to fit between tube and manifold port? Mine are tightly plugged with an allen key screw. I have heard a brake nipple type fitting?

The Allen screw should be 6mm, I use a pair of 6mm grease nipples from Canadian Tire
File or grind the tip off the threaded end and it will let the spring and ball out, throw them away

The plastic tube will heat up, get soft and fall off so twist a piece of soft wire around it or perhaps slip a short piece of heat shrink over the plastic to hold it tight.
Have Fun

 

[Cachnutz]

Wow thanks for all the help everyone,great pics Pete!!
I purchased a couple adapter nipples and will be diving into it hopefully tonight...

Cheers

[mylovelyhorse]

Finally a close up of an air bleed screw. Do NOT over tighten these when closing them or they will snap and then you're buggered!

So - and I just want to be 100% sure - this screw should be removed and something else with the manometer hose connected should be screwed in its place? That’s why there’s a reference to bleed nipples with the end ground down in a later post? Is that right?

[Huzo]

This is not meant to replace anyone’s advice mate, but just to let you know that you MIGHT have it just a bit wrong, not much.
The air bleed screws perform a different function than the adapter nipples.
I am not an expert at this and have not done it myself, but have read it a lot here and think I will learn to do it.
If you wait till Pete wakes up/sobers up.. he will put you right, he has the patience of a Saint for those who genuinely want to learn and you’ll not do better than to ask him.
I would wait a few hours and seek more guidance, but it is not hard.
The button head screws are the ones that you remove to fit the vacuum adapters, but as I said please get all your advice from one known good source and that will be your decision as to where.
Just a couple of final things from me..
Mine is a much older bike than yours, so the vacuum point will likely be in a different place and also make sure your hardware is sound with regard to leak free pipes, if there are vacuum leaks in your hoses etc.. you will not be able to rely on your readings on the apparatus.
Have fun..!

[Huzo]

I just stumbled upon a snippet that takes me back a few years.
When I first took my Norge to Pete for Beetling and a PRoper tune, Pete stared at me over a beer and glasses and asked what I had done.
I said I manipulated the sacred screw (but only a little bit..!)
After a thorough flogging with a wet lettuce leaf, I was given the good news that all was not lost, but I’d done a fair job of rendering a hitherto set of serviceable TB’s to a pile of worthless Italian garbage, unless I could drag a flow bench from my blurter..!
Now that I read the content of this thread a little more carefully, I see that it was not the sacred screw I manipulated, but the black Allen head one as in the pic.

I did that to get the idle from 1400 rpm or so, back to 1100.
Now Pete found there was about “a zillion or so hectopascals difference in the manifold depressions”, so clearly the bastard before me had, but it wasn’t me I promise...!
It (the fast idle), turned out to be a stepper issue but in any case I should have left it alone...
‘Just thought I’d mention it...(for some reason..).

[severely]

Thank you Pete for the up close photos. Makes the job a little less worrisome if you have REAL information to work with.

[80CX100]

So - and I just want to be 100% sure - this screw should be removed and something else with the manometer hose connected should be screwed in its place? That’s why there’s a reference to bleed nipples with the end ground down in a later post? Is that right?

No!

Just in case you want to work on it before Pete logs back on, I'll jump in.

The screw in your photo is the air bleed on the bottom of Throttle Bodies.

The vacumn port used by your manometer is on the side of the intake manifolds, as seen in Huzo's photos, and I'll post another photo that's a little clearer.






Depending on the bike and country, the vacumn ports sometimes have a hose/vacumn line from side to side or plumbed into an epa system IIRC?

If a hose is already attached to the vacumn ports, it's easier to do, just pull off the hose ends, and slip on your manometer hoses, no fittings needed.

It's a bit intimidating doing it the first time, but it's not that complicated, the improvement from a well balanced tuneup is very satisfying.

You got this! good luck

Kelly

[mylovelyhorse]

No!

Thank you Kelly!

These photos are of my 2007 Norge 2v and as I understand it these screws come out to be temporarily replaced with some sort of 6mm spigot to which I attach my manometer. I hope I am right here!

[fotoguzzi]

Yes those circles screws are where you put the hose to check throttle sync

[John A]

you can also use MIG tips for an adapter.  most are metric, 6x1mm

[mylovelyhorse]

Yes those circles screws are where you put the hose to check throttle sync

Excellent, thanks. The right one undid easily. The left one is threatening to round off so I have doused it in PlusGas and will leave it to seep in for a day or so.

[mylovelyhorse]

you can also use MIG tips for an adapter.  most are metric, 6x1mm

Excellent tip (haha! see what I did there?  ) thank you!

[Vagrant]

put the face of a ball peen hammer on the screw head, hit the ball with another hammer it will resurface so to speak the screws head. if you can get a impact driver with the allen head sockets it should break loose right away. if not a bit of very localised heat.

[mylovelyhorse]

put the face of a ball peen hammer on the screw head, hit the ball with another hammer it will resurface so to speak the screws head. if you can get a impact driver with the allen head sockets it should break loose right away. if not a bit of very localised heat.

That’s a great idea, however two days of regular dousing in PlusGas has loosened it off and I got it out this PM 😀