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GTM Secondary Air Supply (SAS) V7-9 Block-off Kit

The synopsis of my ride report is as I stated: "No more barking and popping."

A little more verbosely: The V7III Racer fitted with Agostini mufflers and the GT-Rx customized ECU map runs beautifully, but on overrun conditions the secondary air injection system causes a certain amount of barking and popping to occur, depending on the specifics of RPM, load, ambient temperature, etc. With the SAS block-off kit installed, that annoyance is eliminated.

Whether there is any actual performance gain is a bit too subtle for me to gauge with my butt dyno. :) A forty mile ride yesterday evening seems to indicate a slight difference in the throttle feel and sound the bike produces—all to the better.

(Technical notes for context: The SAS is specifically there to preserve the functionality of the catalytic converters in the OEM mufflers, much like the oxygen sensors. With the catalytic converters, the injection of fresh, oxygen-rich air into the exhaust stream on overrun provides the oxygen needed to consume excess fuel on overrun conditions that would otherwise damage and reduce the effectiveness of the cat-cons over time; it extends the burn and keeps the cat-cons hot enough. If you're running non-OEM mufflers without a cat-con, it causes pops and barks in the exhaust system: the cool, over-rich exhaust stream on overrun burns up to a point and then small fragments of the stream explode chaotically in the exhaust system when it encounters too much free oxygen from the injected fresh air. Blocking off the SAS ports and fooling the computer into not noticing the valve is no longer there prevents this 'rich hot mixture encountering excess free oxygen' condition so the exhaust runs a bit cooler and without the chaotic explosions. It degrades emissions output no more than has been done already by removing the OEM mufflers/cat-cons; might actually improve emissions a tiny bit due to not allowing the high-temperature chaotic explosions to form.)
 
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I just asked a couple of questions over here ...
https://www.guzzitech.com/forums/th...k-installation-v7iii-racer.18146/#post-141339
... but have since found that this thread is better - more pix! If a knowledgeable person would perhaps take a look over there for me, I'd very much appreciate it. In the meantime, for those who've already done this mod, with the little electrical adapter thingy supplied by Todd, have you just cable-tied it out of harm's way under there?

That little plug thingy from Todd just appears to be about a 10W resistor of who knows what resistance - pretty bullet-proof mostly. Any idea what symptom one might expect if it did go open, or short?
 
I responded over on the other thread about the reed valves. The plug-in tells the ECU that all's well with the SAS valve and it's operating correctly. I zip-tied it to the mounting point for the valve, since the electrical connection wants to be in that area. I figure if it failed, the computer would broadcast a complaint through the error notification readout on the dashboard.

It's probably not worth over-thinking this stuff too much. The kit is simple, pull out the SAS pieces and install it, go for a ride. In the end, you can always put it all back... :D
 
Thanks Godfrey. You will get a check engine light if there are any issues with it down the road.
 
Godfrey, why do you put the reed valve back into the blank-off plate? If it is blanked-off, does the reed valve serve any purpose?
 
The inner plate that the reed valve bolts to carries the seal for the blanking plate, and is thus essential for sealing. I saw no reason to remove the reed valve from that inner plate, even if it no longer has any function.

I am not sure why this is the subject of analysis and query. If you simply had the plugin dongle, you could remove the valve and hoses, seal the openings on the OEM air injection port covers and air box, and effect the same thing as the kit's plates without ever even taking the OEM port covers off. There's no need to touch the inner components (reed valve and plate) at all.

The kit's blanking plates make for a cleaner setup on the engine without unused hose connections and caps that could leak. You pop the OEM covers with the hose connection off, transfer the innards to the new ones so they seal up properly, and bolt the new ones back in their place. Simple.
 
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Not sure if this has been asked elsewhere, but I could not find the answer.
If I do this mod, do I need the GT-Rx fueling mod as well? I do plan on the new fuel map, but am getting tight with the money at the moment.
 
This becomes necessary after you change out the mufflers for non-OEM mufflers. Get the ECU tool and do the map first. Later, if you change your mufflers, do this.
 
I did the job.
Firstly, I removed the tank. Took all of 2m20s, starting with seat removal. Believe me, it's NOT difficult.
I did both the SAS system and the carbon canister removal whilst I had clear access. I did fully remove all superfluous stuff.
Total time, to locking the seat down the seat, 2h23m.

If you haven't done this job yet, but intend to, just take the tank off and don't muck around. every thing is right there to get at. Easy peasy!
 
This becomes necessary after you change out the mufflers for non-OEM mufflers. Get the ECU tool and do the map first. Later, if you change your mufflers, do this.

Got it Godfrey;
Thanks for the explanation.

It goes without saying, but I figured I should say it for completeness, that once you do change out the mufflers, request and install a new map for the different mufflers at that time too. :D
 
...
Firstly, I removed the tank. Took all of 2m20s, starting with seat removal.
...

Indeed! Removing and replacing the tank on the Guzzi V7III was extremely easy, the complete opposite of trying to do it on that Ducati Scrambler I had last Summer. That's why I was so reluctant to do it at first—on the Duc, there was no room to work, you couldn't get any view of what you were doing, all the fittings were obnoxiously hard to get to, difficult to handle, easy to break, etc etc.

Ten minutes spent with a flashlight while gently moving the tank around and looking at its connections was all it took to convince me that Guzzi had done it right: it was not going to be difficult to remove the tank on the V7III at all. But it also showed me that there wasn't any real need to disturb the fuel and electrical connections anyway ... nothing became easier after just lifting the tank up and moving it around a little. So I did that. :)

I haven't yet removed the charcoal canister and lines completely, and installed the cap on the vacuum tap on the intake manifold. That's just a few minutes of cleanup to do when a warm afternoon arrives and I'm not riding.. The problem is that whenever those afternoons arrive, I tend to get on one or the other vehicle and go riding! :D
 
... when a warm afternoon arrives and I'm not riding.. The problem is that whenever those afternoons arrive, I tend to get on one or the other vehicle and go riding! :D
Amen to that!! Every time I decide to do a job on it the sun comes out and I get sidetracked into ridin' it instead.
 
Just finished installing the SAS block-off kit for my V7 III Stone and have been for a short test ride. Many thanks to Godfrey for his comprehensive procedures post above. Rather than struggle to remove the very difficult to access hose clamps, I simply cut the hose on each side where it joins the cylinder head fittings. This gives you a little more room to move your hex key on two of the bolts. Rather than removing the throttle cable bracket to better access the foremost bolt on the right hand side cylinder head fitting (see JACoH's post above), I cut off about 3/8" of the short side of one of my 4mm hex keys to create enough head room to comfortably access that bolt. Preliminary indications are that the kit eliminates almost all decel popping.
 
So for the couple of you who have installed the kit, how about a ride report? Have you noticed any differences post-installation?
Much less deceleration popping, and the engine seems smoother. It is a worth while modification. This alone with the ECU remapping equals pretty much a different bike. So much better than stock.
 
I hadn't ridden for a couple of weeks (too much else going on, been riding my bicycle most of the time, etc etc) but took Racer out for a spin last Thursday morning. Topped up the tire pressures first of course ... Never let a bike sit for a few weeks and go riding without doing that!

Dang, that Racer boy is a sweet little moto beastie! The way it's setup now with the radial tires, fancy wheels, properly sorted suspension, the Agostini mufflers, SAS crap gone, etc etc ... I just want to twist the throttle and let it be make music. It sounds and feels so happy to rev it's heart out and takes real work to keep from slamming into the rev limiter in all gears under fifth. The handling and feel are now so secure and predictable, I toss it around through a winding road as if it were my bicycle, and it responds with completely consistent, utterly confidence inspiring willingness. I just love riding it!

The SAS removal really kills most if not all of the popping and barking, makes it MUCH more pleasant to ride and enjoy. Shawn said he took photos doing the SAS removal and will repost my instructions with the photos to illustrate them at some point. I look forward to seeing what he posts on this.

enjoy,
G
 
Tools and Instructions by Godfrey. Pictures by me. I did not take pictures of everything, but follow these great instructions, use the pictures for reference and it is not hard at all. Took me about 2.5 hours and I did remove the fuel tank for extra work room and light.

Tools:
• 10mm combination spanner
• T20 Torx driver
• 3mm, 4mm hex drivers
• stubby 4mm hex driver or key
• large/long screwdriver
• 1/4" drive ratchet, breaker bar, and 6" extension
• 4mm allen wrench
• Angle jaw pliers
• Bent-nose needle nose pliers
• diagonal cutters

Procedure:
1. Run the tank down (or drain it down) so that it's easy to manipulate
2. Set the bike upright using a stand.
3. Remove seat.
4. Remove tank securing bolt (at the rear of the tank under the front of the seat)
5. Slide the tank back about 2-3 inches, then lift at the front. Lift the tank and settle it over to the left on the frame so that you have access to the right-hand cylinder head and under-tank area (right-hand and left-hand are oriented such that you are sitting on the bike).
6. Using the bent-needle-nose pliers, remove the clip holding the tube that goes from the air box to the SAS system valve (right-hand rear of the engine bay) and pull the tube off its fitting.
Step 6.webp
7. Fit the provided sealing cap to the airbox fitting.
Step 7. jpg.webp
8. Remove the sparkplug wire cover (4x 3mm hex) and the sparkplug lead guide bolts (T20 Torx), then pull the plug cap off so that you can move the plug wire and guides out of the way for access to the other bits.
Step 8.webp
9. Using the bent-needle-nose pliers, remove the clip holding the front of the airbox tube from the SAS system valve, and pull the tube off. Set aside.
Step 9.webp
10. Using the bent-needle-nose pliers, slide the clip holding the tube onto the cylinder head fitting down the tube, and pull the tube off the fitting.
Step 10-1.webp
Step 10-2.webp
11. Undo the two 4mm hex bolts retaining the fitting to the cylinder head. (Access is limited, so a stubby allen key or driver helps here, as does patience.) I (Mayakovski) used a universal joint adapter for this part.
Step 11 and 12.webp
12. Remove the fitting and use the angle jaw pliers to pull the reed valve out if it is stuck.
13. Fit the reed valve into the blanking cap. - NOTE the reed valve and blanking caps are NOT symmetrical.
Step 12-1.webp
Step 12-2.webp
Step 12-3.webp
14. Fit the blanking cap to the cylinder head and tighten the two 4mm hex bolts. (I put some Loctite Blue on them.)
Step 14.webp
15. Reposition the tank over to the right on the frame to permit access to the left-hand cylinder head area.
16. Remove the sparkplug wire cover and the sparkplug lead guide bolts, then pull the plug cap off so that you can move the plug wire and guides out of the way for access to the other bits.
17. Using the bent-needle-nose pliers, slide the clip holding the tube onto the cylinder head fitting down the tube, and pull the tube off the fitting. (This is where I found having the large/long screwdriver handy ... I used it to lever the tube clip around so I could grab the ends with the pliers and move it.)
18. At this point, slide the SAS valve off its mounting towards you.
19. Disconnect the sensor electrical plug.
Step 19.webp
Step 19-1.webp
20. Wiggle the SAS valve with the two cylinder head lines out of the bike and set aside
21. Remove the fitting and use the angle jaw pliers to pull the reed valve out if it is stuck.
22. Fit the reed valve into the blanking cap.
23. Fit the blanking cap to the cylinder head and tighten the two 4mm hex bolts. (I put some Loctite Blue on them.)
24. Connect the provided SAS simulator plugin to the electrical harness and zip tie it to the SAS valve mounting point. Use the diagonal cutters to remove the zip tie's free end.
Step 24.webp
25. Refit the left hand cylinder's plug wire guides, plug wire, and plug wire cover.
26. Reposition the tank over to the left and refit the right hand cylinder's plug wire guides, plug wire, and plug wire cover.
27. Lift the tank, center it on the mounting rubbers, and slide it forward to seat it in place properly. Be sure not to trap or pinch any of the under-tank electrical harness.
28. Refit the tank securing rear bolt.
29. Insert the ignition key and start the bike, checking for leaks and proper operation.
30. Re-install the seat.

I was initially going to remove the tank, but I realized there was plenty of room to work with the tank just lifted and settled over to the right and then the left, so no need to undo the fuel connections and pump electricals unnecessarily. Removing the tank doesn't really make any more space for the bits you have to reach.

The whole job, end to end, took me three hours ... I think if I were to do it another time on another bike, it would take a little more than half that. Most of the extra time was spent figuring out how to get access to the particular bolt or clip I needed to work on. I wrote the procedure above so that others would have a clearer idea of what to look for.
 
If I only disconnect the connector from air pump and the connect the electical connector that provided in the kit.
Will this disable SAS yet?
 
If I only disconnect the connector from air pump and the connect the electical connector that provided in the kit. Will this disable SAS yet?
You would need to cap the line at the pump or each cylinder, and disconnect the pump connector with the supplied pigtail. You cannot leave the rubber hoses connected and only disconnect the electrical plug at the pump.
 
You would need to cap the line at the pump or each cylinder, and disconnect the pump connector with the supplied pigtail. You cannot leave the rubber hoses connected and only disconnect the electrical plug at the pump.

Thank you. Sound like it's better to block them off with your kit.
 
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