Please just look around. Your questions are answered already here.. I merged to this thread.
Every dyno run costs me $150 on average with time & $; I don’t own a dyno (yet). And that is on top of my time with the mapping.
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GTM V7 III Exhaust options & Dyno runs
- Thread starterGTM®
- Start date
Every dyno run costs me $150 on average with time & $; I don’t own a dyno (yet). And that is on top of my time with the mapping.
I just realized that I forgot to say which thread. I meant this thread (below)
https://www.guzzitech.com/forums/threads/v7-v9-ecu-programmer-box.15762/page-9#post-139606
Health and injuries haven't been kind to me recently, so stuff has just sat in my shed waiting.
Finally!! Spent some time in the shed last week. SAS system removed, carbon canister breather system removed, Matris front fork upgrade installed and Todd's engineering masterpiece: 2>2 exhaust system ( https://www.guzzitech.com/store/product/gt-rx-v7-iii-2-2-full-ss-exhaust-system/ ) is now installed. Remapped it and have put 280Km up since.
Upon unpacking the exhaust the 1st thing I wondered was, "Is this one meant to hang on a feature wall?" The quality and finish (polished SS) has to be seen to be believed. I have NEVER seen an exhaust on ANY bike which looks so perfect. The flowing line of the headers into the GPMegs is like poetry in SS. What I'm saying here is genuine. Todd doesn't pay me. It's just that good!
Removing the oem system is pretty straight forward. I split the "H" piece and unscrewed the halves from the O2 sensors. It was easy.
Starting at the headers and working aft seemed the way to go for the new system. 1st trap for new players was the 1st thing I did. Just looking casually at the headers on the bench, they look identical - they're not!! Once you do it wrong it becomes blindingly obvious. 1 cylinder is further forward than the other - Duh!! Face palm moment! The difference appears to be at the beginning of the header, where it exits the port. After that it's all pretty easy. I separated the halves of the new "H" pipe and screwed them onto the O2 sensors (as different from screwing the O2 sensors into the pipes). Get all the ducks lined up before tightening up any bolts/screws. Start at the exhaust ports and work aft. Be meticulous about getting the headers pushed firmly and squarely into the ports. I assembled the "H" pipe under the bike because the O2 sensors were already installed. There was no problem at all doing it this way. I'd recommend doing it this way in fact.
Wasted no time flashing the ECU and started it up the shed. Shouldn't have done that! It was so loud that I immediately thought that I'd done the wrong thing buying this system. Thought about what fun Mr Plod would have with me on the side of the road. Any'ow, it was wasted worry.
Due to rain, thunder, lightning and hail it was a couple days before I got for a ride. The sound is like music. In the great outdoors it's nowhere near as loud as in my tin shed. Certainly not as obnoxious as a Hardley Driveable. A lovely throaty, mellow rumble - except when I get right amongst it. It barks then! The pipes and the fueling are very well matched. It'd be interesting to find out just how much extra torque/power is available, but it's most definitely noticeable throughout the entire rev range. Most extra kick I think is around 4,000rpm and upwards. It pulls so strongly that I found myself hitting the rev limiter far too often - not trying to, but just wringing its neck the way it begged to be wrung. There must be at least an extra 1,000rpm in there.
The mid to upper end improvements are startling, but the lower end hasn't been sacrificed for that gain. In 1st, I can slip the clutch, just minimally, and pull away smoothly at idle - right hand off the bars. Without touching the throttle, and with very little clutch slip I could change to 2nd, and then 3rd. Idling around in 3rd gear is easy and smooth. Gently feeding in a little throttle would have me pulling away with no hesitation or snatching what-so-ever. 4th gear, at idle, induced a little snatch.
If you're prevaricating in any way about which exhaust/muffler combination to have, or even whether or not to upgrade your exhaust, prevaricate no more. At absolute best, any other system can only be 2nd best, and the oem system is not even in the same game.
A little post script here: I've been really caning this thing (as noted above, hitting the rev limiter regularly) but my fuel consumption has improved. Where I was doing a regular 51 to 52 mpUSg I've averaged 53.7 mpUSg so far with the new system. I'm a little bemused myself, but those figures all come directly from the on-board computer.
Finally!! Spent some time in the shed last week. SAS system removed, carbon canister breather system removed, Matris front fork upgrade installed and Todd's engineering masterpiece: 2>2 exhaust system ( https://www.guzzitech.com/store/product/gt-rx-v7-iii-2-2-full-ss-exhaust-system/ ) is now installed. Remapped it and have put 280Km up since.
Upon unpacking the exhaust the 1st thing I wondered was, "Is this one meant to hang on a feature wall?" The quality and finish (polished SS) has to be seen to be believed. I have NEVER seen an exhaust on ANY bike which looks so perfect. The flowing line of the headers into the GPMegs is like poetry in SS. What I'm saying here is genuine. Todd doesn't pay me. It's just that good!
Removing the oem system is pretty straight forward. I split the "H" piece and unscrewed the halves from the O2 sensors. It was easy.
Starting at the headers and working aft seemed the way to go for the new system. 1st trap for new players was the 1st thing I did. Just looking casually at the headers on the bench, they look identical - they're not!! Once you do it wrong it becomes blindingly obvious. 1 cylinder is further forward than the other - Duh!! Face palm moment! The difference appears to be at the beginning of the header, where it exits the port. After that it's all pretty easy. I separated the halves of the new "H" pipe and screwed them onto the O2 sensors (as different from screwing the O2 sensors into the pipes). Get all the ducks lined up before tightening up any bolts/screws. Start at the exhaust ports and work aft. Be meticulous about getting the headers pushed firmly and squarely into the ports. I assembled the "H" pipe under the bike because the O2 sensors were already installed. There was no problem at all doing it this way. I'd recommend doing it this way in fact.
Wasted no time flashing the ECU and started it up the shed. Shouldn't have done that! It was so loud that I immediately thought that I'd done the wrong thing buying this system. Thought about what fun Mr Plod would have with me on the side of the road. Any'ow, it was wasted worry.
Due to rain, thunder, lightning and hail it was a couple days before I got for a ride. The sound is like music. In the great outdoors it's nowhere near as loud as in my tin shed. Certainly not as obnoxious as a Hardley Driveable. A lovely throaty, mellow rumble - except when I get right amongst it. It barks then! The pipes and the fueling are very well matched. It'd be interesting to find out just how much extra torque/power is available, but it's most definitely noticeable throughout the entire rev range. Most extra kick I think is around 4,000rpm and upwards. It pulls so strongly that I found myself hitting the rev limiter far too often - not trying to, but just wringing its neck the way it begged to be wrung. There must be at least an extra 1,000rpm in there.
The mid to upper end improvements are startling, but the lower end hasn't been sacrificed for that gain. In 1st, I can slip the clutch, just minimally, and pull away smoothly at idle - right hand off the bars. Without touching the throttle, and with very little clutch slip I could change to 2nd, and then 3rd. Idling around in 3rd gear is easy and smooth. Gently feeding in a little throttle would have me pulling away with no hesitation or snatching what-so-ever. 4th gear, at idle, induced a little snatch.
If you're prevaricating in any way about which exhaust/muffler combination to have, or even whether or not to upgrade your exhaust, prevaricate no more. At absolute best, any other system can only be 2nd best, and the oem system is not even in the same game.
A little post script here: I've been really caning this thing (as noted above, hitting the rev limiter regularly) but my fuel consumption has improved. Where I was doing a regular 51 to 52 mpUSg I've averaged 53.7 mpUSg so far with the new system. I'm a little bemused myself, but those figures all come directly from the on-board computer.
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Sounds great! And virtually identical to what I'm getting on Racer with the Agostinis and Todd's ECU map. I bash into the rev limiter so easily now it's amazing—I'm very glad the rev limiter is there!
Of course, the Ago setup is just the mufflers ... header pipes and crossover remain stock ... so fitting the Agostinis is, if anything, even simpler. Basically one clamp and one bolt per muffler. Takes less than five minutes to install them. But it's not a full SS system, of course.
Of course, the Ago setup is just the mufflers ... header pipes and crossover remain stock ... so fitting the Agostinis is, if anything, even simpler. Basically one clamp and one bolt per muffler. Takes less than five minutes to install them. But it's not a full SS system, of course.
From what I understand, Todd's cross-over is what makes the lion's share of the difference - performance-wise.
Adding to my tome above, the engine seems to running even cooler than the stock pipes with Todd's map. With 280Km on the new system, the single walled headers have barely begun to change colour. Just the slightest tinge of straw colour beginning to happen.
Adding to my tome above, the engine seems to running even cooler than the stock pipes with Todd's map. With 280Km on the new system, the single walled headers have barely begun to change colour. Just the slightest tinge of straw colour beginning to happen.
Color isn't an issue for me; my bike's pipes are black anyway. 
From an academic/engine tuning perspective, I wonder exactly what the performance differences are. Unless the ID of the header pipes and crossover are substantially different, and the crossover is positioned in a different location relative to the exhaust port, the usual biggest influence is the total pipe length from exhaust valve to the end of the exhaust pipe. The rule of thumb that I've always used (based on information presented in "The Design and Tuning of Motorcycle Exhaust Systems" by Phil Irving) is that a shorter pipe biases the power band upwards in the rev range and a longer pipe biases the power band downwards in the rev range. The Agos are about six inches longer than the GT full system, so I'd expect the Agos to enhance mid-range at some expense of top end, and vice versa. But the Agos themselves are about four inches shorter than the OEM mufflers—and by direct observation, they're not holding the engine back from wanting to spin past redline already...
(Note) The performance differences are a purely academic interest to me. I'm perfectly happy with how Racer's engine is performing now and whatever small percentage differences there might be would really all be a wash at this point. The engine starts, warms up, and runs just right, doesn't seem to run hot at all, makes plenty of GO for being silly, and sounds terrific.))
One detail that is often overlooked is that the GT full system, since it is shorter, provides more clearance for bags and such on the Racer. The Agos are a bit slimmer and shorter than the OEM system but still don't provide much room for bags due to the upswept design for ground clearance and style.
From an academic/engine tuning perspective, I wonder exactly what the performance differences are. Unless the ID of the header pipes and crossover are substantially different, and the crossover is positioned in a different location relative to the exhaust port, the usual biggest influence is the total pipe length from exhaust valve to the end of the exhaust pipe. The rule of thumb that I've always used (based on information presented in "The Design and Tuning of Motorcycle Exhaust Systems" by Phil Irving) is that a shorter pipe biases the power band upwards in the rev range and a longer pipe biases the power band downwards in the rev range. The Agos are about six inches longer than the GT full system, so I'd expect the Agos to enhance mid-range at some expense of top end, and vice versa. But the Agos themselves are about four inches shorter than the OEM mufflers—and by direct observation, they're not holding the engine back from wanting to spin past redline already...
(Note) The performance differences are a purely academic interest to me. I'm perfectly happy with how Racer's engine is performing now and whatever small percentage differences there might be would really all be a wash at this point. The engine starts, warms up, and runs just right, doesn't seem to run hot at all, makes plenty of GO for being silly, and sounds terrific.
))One detail that is often overlooked is that the GT full system, since it is shorter, provides more clearance for bags and such on the Racer. The Agos are a bit slimmer and shorter than the OEM system but still don't provide much room for bags due to the upswept design for ground clearance and style.
Tequilasunriser
Just got it firing!
scudracer
Tuned and Synch'ed
Hi all,
Had the GP Megs on for a little while now so about time I comment
Now the sound. I love the thumping idle. Makes me think of a hard rock drummer really giving his skins a good bashing. Love it. I also love the sound when decelerating at speed, not sure how to describe it, just that nice deep twin sound. And obviously there's an appropriate aggressive growl on throttle openings!!
These are probably the loudest pipes I've owned, so my initial thought was maybe a tad too loud. Having said that however, I thought my last bike wasn't loud enough! Now though, on the bike, hearing that thumping idle coupled with that Guzzi engine vibes at idle, can't help but think to myself "this is cool". The sounds suits the bike. It sounds like it should.
Here are some pics, hopefully give a good view from multiple angles...For more pics check out the newer ones in my flickr album:
https://www.flickr.com/photos/iamthefinn/albums/72157684039848883
Still on stock fueling...Have just ordered the ECU reflasher tool, just waiting for restocking before I can get my hands on it. In the meantime, I know there is a dyno graph on this site for V7 III with GP Megs and stock fueling, but are there any with GP Megs and after ECU remapping?
Cheers!
View attachment 13836 View attachment 13837 View attachment 13838 View attachment 13839 View attachment 13840 View attachment 13841
Love it! That's it. I think this is what I'll be saving up for on my V7 I Special.
SeriouslyDudeLetsGo
Just got it firing!
Hey everyone.
Long time lurker, first time poster. I was wondering if anyone in the Los Angeles area had the
V7III GP MEGS with the ECU remap on their bike: https://gtmotocycles.com/collections/exhaust/products/gt-motocycles-ss-v7iii-gp-megs?variant=14327878615083#shopify-product-reviews
not the entire system: https://gtmotocycles.com/collection...-motocycles-v7-iii-2-2-full-ss-exhaust-system
I'm 90% sure I want to get the megs and remap tool, but I have to double check in person since I live in quiet neighborhood and work weird hours. Can anyone meet up? Otherwise, I'll make the drive out to OC to visit Todd if possible.
Long time lurker, first time poster. I was wondering if anyone in the Los Angeles area had the
V7III GP MEGS with the ECU remap on their bike: https://gtmotocycles.com/collections/exhaust/products/gt-motocycles-ss-v7iii-gp-megs?variant=14327878615083#shopify-product-reviews
not the entire system: https://gtmotocycles.com/collection...-motocycles-v7-iii-2-2-full-ss-exhaust-system
I'm 90% sure I want to get the megs and remap tool, but I have to double check in person since I live in quiet neighborhood and work weird hours. Can anyone meet up? Otherwise, I'll make the drive out to OC to visit Todd if possible.
I believe someone running the GP Megs stopped by while I was at the shop last year getting my suspension and wheel work done. It impressed me as being a sound very similar to the Agostini mufflers that I'd fitted, which sound much louder to me riding the bike than they do when I let a friend of mine blast past me on it. And it's a reasonably pretty, mellow sound ... Most people who hear it either ignore it completely or like it.
SeriouslyDudeLetsGo
Just got it firing!
Thanks for the reply! I ended up getting the GT Megs and remap tool and SAS airblock kit. Having Todd install it in the coming weeks. Probably going to shoot a video of the before and after. Thanks for all your help!I believe someone running the GP Megs stopped by while I was at the shop last year getting my suspension and wheel work done. It impressed me as being a sound very similar to the Agostini mufflers that I'd fitted, which sound much louder to me riding the bike than they do when I let a friend of mine blast past me on it. And it's a reasonably pretty, mellow sound ... Most people who hear it either ignore it completely or like it.
Louisv97
Cruisin' Guzzisti
Hey Todd just wanted to thank you again for these stubbys they sound glorious!!!! And the pops are so good!
FinnF4i
Just got it firing!
Well after having the Megs for a couple years now I think it would be, still loving them and finally got around to shooting some quick videos. As usual take sounds clips for what they are, I'm sure the Mic in my camera isn't that great, and I'm sure the inbuilt mobile device speakers will do them no justice...
But anyways:
https://flic.kr/p/2hiQWMn
https://flic.kr/p/2hiNbFr
https://flic.kr/p/2hiNbrJ
https://flic.kr/p/2hiQW9D
But anyways:
https://flic.kr/p/2hiQWMn
https://flic.kr/p/2hiNbFr
https://flic.kr/p/2hiNbrJ
https://flic.kr/p/2hiQW9D
Louisv97
Cruisin' Guzzisti
GT options for the V7 III. Mufflers or Full 2:2 & 2>1 systems. My offerings available on the Store tab above.
GP-Style Meg Muffler:
Prototyping our full Classic system also;
Weight comparo...
OEM muffler 10.8 lbs
View attachment 12166
GT-Rx® Long Meg 2.6 lbs
View attachment 12167
each muffler is 10 lbs??? jesus
PokeyGuzzi
Tuned and Synch'ed
Sounds right. I put a 2>1 exhaust on my bike, and while there is supposed to be a increase in HP, the biggest difference I noticed was the reduced weight. Plus it looks and sounds awesome
Vagrant
GT Reference
I took the full exhaust off a 1997 Valkyrie once and put on a supper trapp. 27# lighter and that was pre cat systems.
It was just brought to my attention by a customer that took a gamble on my megs fitting the Mk I (& II) below, seems they fit and work; https://gtmotocycles.com/products/gt-motocycles-ss-v7iii-gp-megs - I try to keep a few pair on the shelf.
Daniel Berthold
Just got it firing!
Looking at your site Todd I can't see any header pipes/full systems for the V9's. Are the headers the same for V7iii and V9? I've converted my V9 into a v7 like you did including changing the the frame rails. I'm also running Agostini hydroformed slip ons from my older v7i on it but it looks a bit of a mish mash. Any suggestions?