Thursday, February 3, 2011

LeoVince Pipe Shoot-out @ 49cc

The New ZX-R

With the newest release from LeoVince in performance pipes for the Aprilia SR50 Ditech, the LeoVince ZX-R,  we have been anxious to see how it stacked up against the LeoVince ZX and the LeoVince GP offerings. It's rumored the ZX will be replaced permanently by the new ZX-R later this year or whenever they are out of ZX inventory. Upon first inspection, the silencer and the exit pipe is noticeably larger. The exit pipe of the ZX will actually fit inside the tip of the ZX-R. The silencer body sports a new Carbon Fiber wrap over a stainless steel tube. I must say this is a huge visual improvement over the Kevlar / Carbon silencer on the ZX. The label on the silencer is also adhesive rather than riveted like the ZX.

We are told that the ZX-R was introduced to be a much quieter expansion chamber and that it is. Before we had a chance to put it to the test, many were delivered to anxious SR50 owners sporting the much louder ZX looking for something that would let them get home late at night without waking up the neighborhood. The feedback we received was it was just slightly louder than the stock pipe. Other than the silencer, the pipe appears to be the same as the ZX.

First we must derestrict

Our scoot is a brand new 2009 SR50 DiTech with the 49cc Piaggio engine which we just received in the US in late 2008. The first change made was to derestrict the ECU by putting it into Dealer Development Mode with version 2.8.0 software. This has been the best running software we have tried out of the last 3 releases. This is a must before going forward with any performance enhancements and this one change alone is a big improvement. Out of the crate, the 2009 SR50 produces 3.80 HP with a limited top speed of 45 mph. Derestricting the ECU immediately pushed us up to 4.41 HP with a 3 mph speed increase.

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A noticeable increase in acceleration was also recorded by the Dyno.

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The next change before the pipe testing began was to derestrict the variator by removing the small spacer that keeps it from making a full transition. Along with the ECU electronic limits, this is what holds the scoot to 45 mph. What a difference 2.3 mm makes... another 7-8 mph

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This is what the 2 derestrictions  look like compared to the stock restricted run

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Time to test

I first removed the 5.3gr factory rollers and installed the lighter 5.1gr. rollers (package says 4.8gr.) and red clutch springs LeoVince provides with the Piaggio pipes... a nice little bonus so your not guessing where to start. 3 pulls were taken with each pipe and before testing the pipe was fully warmed up. All 9 pulls were within 30 minutes so there wasn't much change in the environmental to affect the outcome. Shop temperature didn't change by over 1 degree. The first pipe ran was the ZX-R, then the ZX and last the GP. This is what all 9 runs look like.... very closely matched with no big stand-outs.

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Taking the best run from each pipe, I plotted them out with our derestricted results with the factory pipe. Each pipe kept the power band very consistent with the factory pipe telling me LeoVince did their homework.

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The results

All 3 pipes performed quite well over the very heavy factory pipe with the ZX adding an extra 1/2 horse power over stock. The huge weight decrease alone is enough of an improvement to switch to a performance pipe. If your looking only at peak horse power, the ZX wins with a slight margin over the others. If you look closer throughout the run, they each take their turn on top. Can you feel 1/2 a horse power at that level.... yes. Can you feel 8 one hundreds of a horse power.... no. To get the ZX-R pipe as quiet as they did with little to no decrease in horse power, LeoVince did an excellent job. And how about that LeoVince GP pipe.... Stainless Steel and excellent looks with no sacrifice in performance... how'd they do that?