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GuzziTech GTM modded Cal 14 Dyno vs. Stock

GTM®

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GT di Razza Pura
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I finally got the GTM® modded Cal14 on the Cycle World dyno late yesterday, and the results are below. A completely stock 1400C shown as a blue trace below, then with my GTM® Slip-on mufflers and H-pipe with opened air box lid and GTM® Fueling kit, results in the green trace: ~6-8 hp constant gain, and 8 lb.ft where you'll live the most.
With the full GTM® Exhaust & Fueling Kit (install How-to HERE) along with the modded air-box lid & K&N filter (gold trace) = Long mufflers give ~20 hp & 20 lb.ft. gains over stock, short mufflers give ~25 hp & 27 lb.ft gains with the full system (see dyno charts below) with a 40 degree lower operating temperature with full kit! See videos in second post below.

GuzziTechC14DynoRuns.jpg

GTM full system, short mufflers with open lid airbox and full fuel system only... 105 rwhp/102 ft.lbs! That's +25 hp & ft.lbs -- a ~30% increase in power over stock.
C14-GTMShrtFS-Dyno105.jpg

Hey Todd, that is a nice result. Having 65hp at 4000 revs is a lot of mumbo where I would use it most, for general riding and passing on the freeway. I would like that out of my 1200 Sport.

I have a technical question about running bikes on the dyno. How fast did the engine run up through the revs? Or, in what gear did they perform this test? The reason I ask is because I suspect that bikes with heavy flywheels are penalized for being slower to rev. It takes power to spin the engines own inertia up to top revs that might not be factored into the calculations. Is there a way to configure more resistance on the dyno or choose a higher gear (say 5th gear or top gear) so that the climb is slower? This would reduce the effect of the heavy flywheel and might provide an even better result.
 
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GTCal14CWDyno-2.jpg

GTM Full polished system with short mufflers:
5b1a7ace-0805-48cb-9f9c-e18702b8dd74-jpeg.18843

Short full system shown above, sound below:


Long muffler system sound:

Custom MGX-21 full system - Contact us above for more info.
 
Hey Todd, that is a nice result. Having 65hp at 4000 revs is a lot of mumbo where I would use it most, for general riding and passing on the freeway. I would like that out of my 1200 Sport. I have a technical question about running bikes on the dyno. How fast did the engine run up through the revs? Or, in what gear did they perform this test? The reason I ask is because I suspect that bikes with heavy flywheels are penalized for being slower to rev. It takes power to spin the engines own inertia up to top revs that might not be factored into the calculations. Is there a way to configure more resistance on the dyno or choose a higher gear (say 5th gear or top gear) so that the climb is slower? This would reduce the effect of the heavy flywheel and might provide an even better result.
Thanks, and the more impressive feel is just off idle and mid-range roll-on, which isn't shown on the graph above.
Most dyno pulls are done in higher gears, yes. I personally did the runs, and used 5th gear. Flywheel weight has little effect on the numbers on the dyno other then the rate/time in which they achieve max power.
 
Hi Todd, there is a dyno available just down the road from my mechanic, so as soon as my new parts are received and fitted, I'll head down there.
I'll also report back in detail
on-road impressions. Looking forward to arrival.
 
Im curious as to how the ECU mods effect the stock fuel profiles of rain, touring, and speed. Are they still available? Do they still perform their functions, ie does the rain profile still reduce engine power?
 
Im curious as to how the ECU mods effect the stock fuel profiles of rain, touring, and speed. Are they still available? Do they still perform their functions, ie does the rain profile still reduce engine power?
Yes, full functionality is still in place. Again, AFR/fueling is seperate from those settings. The "map" settings all limit power to the rear wheel at various throttle positions using the traction control feature. Even the Veloce/Race setting does not give full power to the rear wheel anywhere in the table, including full throttle.
 
Oh ok. Thanks. So is it like you have one main map and the 3 profiles just determine when power is limited on that map?
 
Yes, one main fuel map. An internal combustion engine requires a specific air/fuel ratio. Which A/F target ratio is dependent on many variables; Air-cooled engines are largely fuel cooled, so lean emission requirements crush power and add immense heat. Modern engineering to keep most from melt down, much less even run (in stock trim), is nothing short of miraculous.
A/F Ratios on modern Guzzi make everyone even slightly knowledgable with fueling, cringe at the sight.
 
....Am I interpreting correctly?...that torque is lower until mid-5000 rpm range?....or, ?....
 
Am I interpreting correctly?...that torque is lower until mid-5000 rpm range?....or, ?....
No. Both HP and Torque have impressively increased as hopefully (more clearly now) noted below:

GTCal14Dyno-Noted.jpg
 
I'm thinking the fuel and airbox mods and the stock pipes might provide enough gains and still keep her purring nice and quiet.

I still haven't hit the first service mark but I'll be watching this space.
 
OK, I was finally able to do a real overlay shown below. Completely stock bike = blue lines, GTM® Mufflers, and opened air box lid with GT fueling kit = green lines, GTM® Exhaust, Open lid air box w/BMC and full GT fueling kit = gold lines. Again, almost 20 hp and 20 ft. lbs. of torque gains.

GuzziTechC14DynoRuns.jpg
 
Those are phenomenal gains ... this engine likes to breathe!

Todd, tell me more about the "Open lid air box w/BMC" ... BMC is a drop-in replacement panel filter right? Is the lid just removed from the stock air box or is there more?
 
Those are phenomenal gains ... this engine likes to breathe! Todd, tell me more about the "Open lid air box w/BMC" ... BMC is a drop-in replacement panel filter right? Is the lid just removed from the stock air box or is there more?
Heh, well, it doesn't like to be choked as it's delivered. ;)
For the modified lid, I just completely cut and removed the area above the filter. You can DIY by doing the same or drilling a bunch of holes in that area. The filter is held on by trim ring, from the inside of the lid, and use a high-flow element from our online STORE. I need to mention here, that even a bone stock bike really needs the fueling corrected (dealers cannot do this) in order to have a long, healthy life. Any modifications exacerbates the uber-lean fueling.
 
I've gone through a full tank of gas since Todd installed his magic on my fueling system.

All I can say is WOW! I'm still running the stock exhaust so I might not have the gains that one would get with Todd's exhaust system but the bike has been transformed. Previously, I had to keep it above 3000 RPM at all times because it didn't fuel properly below that and would surge and stumble. Now, she pulls strongly and the engine seems to have less vibration and it just hauls ass.

As an added benefit, fuel mileage has increased dramatically! I would average around 34 MPG prior to the mods. This last tank was a mix of freeway and curves in the hills and city riding. 43 MPG!

Todd's service was awesome. If you have the dough, you can't afford NOT to do this.
 
Todd's service was awesome. If you have the dough, you can't afford NOT to do this.
Thanks Buzz! Cooler running engine, more power, better MPGs... and best yet, a BIG smile maker when you twist the throttle. See you again soon.
 
Thanks Buzz! Cooler running engine, more power, better MPGs... and best yet, a BIG smile maker when you twist the throttle. See you again soon.

I'm sure I haven't achieved your HP and TQ with my stock exhaust but it's still better than stock and I like the quiet cruise.
 
As an added benefit, fuel mileage has increased dramatically! I would average around 34 MPG prior to the mods. This last tank was a mix of freeway and curves in the hills and city riding. 43 MPG!

How did you measure your mpg, from the dashboard? Remember, the dashboard only knows what the ECU is telling it, and is unaware of the changes the power commander is making. If you note your fuel quantity when refilling and the mileage since the last refill, you can calculate the true mpg. The results may not be so wonderful; I was fooled by this for a while too, until I thought it through.

Notwithstanding my comments, I agree the GTM fueling package is very impressive.
 
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