Project 90 (Stock 89cc And Beyond)

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Worry not coz you are not the only one. We are around the world loving the 2t madness and our neighbors. Ride safe and safer during night rides.

[90GTVert]

Phase 4 : Leo Vince ZX 50-70cc


For this test I am going to try the 50-70cc version on the Leo Vince ZX exhaust. I picked it up used for a great price and compared it to the 100cc version of the ZX, but only with sight and measurements so far. You can see plenty of pics and diagrams and other info in the 50cc vs 100cc Comparison link below. As you can see in that thread, this is the model for a Yamaha Zuma which uses a different mount and has dents in the pipe to clear the centerstand. Otherwise the main difference in the design of the pipes appears to be a larger header section for the 100cc version. The 100cc has been de-restricted by removing both the cone in the header and the sound deadening inside the expansion chamber. De-restriction info is linked to below as well. I have also provided links to the 100cc ZX tests on Project 90 for comparison purposes.

50cc vs 100cc ZX Comparison
100cc ZX Phase 1 Test
100cc ZX Phase 2 Test
100cc ZX Phase 4 Test
ZX De-restriction Info


Mounting the ZX intended for use on a Yamaha Zuma took a little bit of work. I first tried with it as it came. To get the mounting holes nearly lined up it sat at an angle that pressed the pipe into the rear tire.






The pipes are so similar that I thought I could simply swap the bracket from the 100cc version that has worked well onto the 50cc version.




That didn't work out either. It seems the 100cc has the mount placed farther back, because it's bracket comes too far forward when attached to the 50cc ZX.






I ended up using a mounting bracket from one of 190mech's older style Peace Pipes with an extra hole drilled to match up to the case and ZX properly. You could make the same thing with some 1/4" thick aluminum. You'll also need a spacer or washers as shown in the second image below.






Here's a look at it installed.




I wish I could say getting the 50-70cc ZX mounted was the end of my troubles with this test, but I definitely cannot. I left the carburetor and CVT setup as tuned for the 100cc ZX with a 100 main jet and 6g sliders, otherwise unchanged from the baseline tune.

When I fired the engine up it was obvious that the tune that worked for the 100cc ZX test was not working for this one. It sputtered and chugged out smoke and lacked power. It appeared to be very rich, so I started working on tuning the carburetor. I tried a huge range of jets and nothing I did seemed to be working. I could get it to run rich or run lean, but it never felt like it was in tune. It felt dead. I thought perhaps something was wrong with the carburetor, so I disassembled it and did a thorough cleaning.




After cleaning the carb, I swapped around a few jets that had seemed the closest. Still weak. Takeoff had no kick, it struggled to accelerate, and revs were low. It reminded me a bit of what I had seen in the past with an engine suffering from low compression. I did a compression test and found it to be at 175psi, dead on where it was when tested for the baseline.




I hadn't even taken the scooter on the road at this point. I had just been riding around the yard, because it was so far from feeling like it should. I put one of the better performing main jets in, I believe it was a 90, and took it out for a brief test ride. It reminded me an awful lot of riding a stock 49cc scoot. I managed to get the scooter up to 38MPH at about half tuck with a slight tailwind.




Something has to be pretty far off to lose about 20MPH! At that point I started thinking there has to be another restrictor in this thing. I was sure I removed the header restriction. I couldn't imagine the little bit of sound deadening in the convergent cone would have this sort of effect, and I had ran my 100cc ZX with that in place with no troubles. I pulled the silencer off thinking that maybe LV had started using restrictors in that area as I've heard of other manufacturer's doing.






Nothing there. Hmmm. Well, I wonder if it's possible that the smaller header of the 50cc version coupled with the dents for fitting a Zuma's center stand are reducing volume so much that it's running weak? I wouldn't think so, but I was running out of ideas, short of cutting the pipe apart for a look or installing a different pipe to see if it was actually an engine related issue. Here's another look at those dents, shown with the unbeaten 100cc ZX.




I removed the exhaust from the scooter to possibly try and remove the dents and what did I see?




That's right, the header restriction that I was certain I had removed was still in place. I could have sworn it was gone and even looking over the flange to fit a gasket and install it I never noticed it since it was black in a black header. I had to have looked right at it, but I "knew" it wasn't there so I never looked for it. To make that really long story short, don't be a dummy like me. Pay attention to every detail when you do things like this. Don't be in a hurry. That 5 seconds you save could cost you hours. It did for me. Part of me wanted to leave this out, because frankly it made me feel like an idiot. I'd rather feel dumb and give you more info though than leave it out. So now we can all see exactly what happens when you run with one of those restrictors in place. Jetting changes a lot and a 96cc runs like a 49cc.

I ground out the weld and removed the restrictor.










Just how small is this thing? About 10mm smaller than the header would normally be at the flange.




I smoothed out the inside of the header and gave it a quick coat of BBQ grill paint.




Since the exhaust was off and we've had a few days of rain, wind, and low temps, where I wouldn't be riding anyway, I decided to go ahead and try to freeze the dents out of the exhaust. It seems like it would be a more fair comparison between the 50-70cc and 100cc pipes if this one were not bashed in. Reading comments from people that have used the dented Zuma pipes it seems they do work alright, but it's hard to believe it would have no effect. Here are a bunch of shots to give you kind of a 360 view of the dents.


















I filled the pipe with water the best I could. Some suggest submerging the pipe to fill it faster. That would be a good idea. I took the more time consuming method for some reason and filled it from a faucet. Once I got a bit of water in there I plugged the stinger end of the pipe so I could move it around without the water coming out, because I had to fill a little then change angles to get the water to go through the header and into the body. Kept doing that till it was full and then capped of the header using an aluminum plate and an exhaust gasket.






I've seen some people saying sealing is not necessary and others saying it is. As you can see, I opted to seal it. I don't think it was necessary for me, at least not on the stinger end. The rubber cork was pushed out during the process, once everything was pretty well frozen. I think if you have dents in the larger, more central, areas like I did, the small areas on each end like the stinger and header will probably freeze up and contain the pressure in the larger areas.

I put the pipe in the freezer at 3PM, wrapped in a towel to keep my TV dinners clean. By around 8PM it had frozen up and pushed the rubber cork out of the stinger end. I checked it about every 30 minutes to an hour until around 11PM and saw very little change before I went to sleep. I woke up at 3:30AM and found that the dents had been mostly removed. I was quite happy to see this and stayed up till 4:30AM, checking each half hour. At 4:30AM I saw no more change and opted to go back to sleep for a bit. I got up at 6AM and the dents seemed the same, but I decided to give it a little more time before giving up, even though I didn't have much hope for the dents coming out anymore since it had been 2 1/2 hours since I noticed them pushed most of the way out. I also set the freezer to it's coldest setting to see if that would do anything. I removed the pipe from the freezer at 9AM when I noticed that it had busted open. It broke open where the Leo Vince Hand Made stamp is. It seems the stamp made this area the weak spot. I don't fault them for that, it seemed to hold up to a bit of pressure before letting go, and I'd prefer it to bust there than at a seam where it may distort worse and be harder to fix.













So the actual dent removal was done within 12 1/2 hours in my case. Possibly a little sooner since I was sleeping and not checking between 11PM and 3:30AM. I don't suggest using my time as a guide though. Volume of the pipe, temperature, material, material thickness, and probably other variables could change the time significantly. I'd suggest freezing the pipe in the morning on a day when you will be able to check on it often. Perhaps settle on the dents being mostly removed rather than busting your pipe open like I did. Look for signs of swelling in areas that aren't dented and remove the pipe from the freezer if you see that. Be prepared for the possibility of the pipe splitting or cracking and needing to be welded if you choose to try this method. Do it at your own risk.

I was very pleased with the results, other than me leaving it in the extra time to cause damage. The dents are much much better. Still present, but barely. Here are a bunch of shots all around the dented area after the pipe was frozen.


















After everything thawing out, I bent the blown out area back and welded it up. I painted the pipe with BBQ black to keep it from rusting and re-installed it. It felt like a beast when I fired it up after hearing and feeling it with the restrictor in place previously.




With the pipe free of any major restrictions, I got it tuned. Tuning was very simple. I just went back to the settings I had used with the 100cc ZX. I used a 100 main jet and put the W9 needle back in with the clip next to leanest. I did try the clip richer after having some part throttle heat and ping on the 100cc ZX test, but it sputtered like it was too rich. Later, on the test ride, I saw results that lead me to believe a 98 main jet may have been a better choice. It performed well with the 100 though.


Here is a video so you can hear this pipe revving and while riding. Please note that if you try to compare this clip to the clip of the 100cc ZX there are a couple of differences. The 100cc clip was done with a stock airbox, while this one was done with a modified airbox. You can hear the airbox noise more in this video. The 100cc ZX has the sound deadening material in the convergent cone removed and this one does not. I think you can pick up the difference that makes between the two videos. With that material intact, the ZX is a pretty quiet pipe.


www.youtube.com/watch?v=ugnAEVR--bw


I went on a 37 mile ride and got 52.12MPG, right on par with the other pipes so far. 40MPH cruising was done at about 8,400RPM at light throttle, just like the 100cc version of this exhaust. WOT cruising speeds could not match up to the 100cc ZX however. I saw 50-53MPH sitting up at full throttle on flat ground, usually hanging around 51MPH, while the 100cc ZX cruisied at 52-54MPH in the same conditions. The 50-70cc ZX couldn't match the 100cc in max speed either. Top speed was 59MPH at just over 8,900RPM, 2MPH shy of the 100cc pipe's 61MPH max. Acceleration felt strong, but again not quite as strong as the 100cc pipe.




Outside air temp for the ride was 55°F. 40MPH cruising showed 275 - 290°F cylinder head temps. WOT riding heated up to 280 - 295°. Both of these readings are cooler than the 100cc ZX tuned the same way. The WOT temp is just slightly cooler, by about 5°, than what I'm used to seeing from a lot of pipes. This is the reason I mentioned earlier that it could have possibly used a 98 main jet. It ran well though and the plug looked good. I don't think it had any significant effect on power and it could just be related to how the pipe was working. One thing is for sure though, this 50-70cc Leo Vince ZX did not cause me any overheating issues on the 96cc engine.


I wouldn't say the 50-70cc ZX did bad, but it definitely didn't perform as well as the version intended for this displacement. The rev range that the pipe was comfortable in matched up spot on. Both pipes felt very similar, this one just lacked a little power. This version matched up very closely to the performance of the 50-70cc Leo Vince SP3 tested earlier. I think I'd rather have that pipe and keep a stock look and a little lower RPM at that rate. I'm not sure if the header volume is the key here, or if it is partially due to the additional modifications I've done to the 100cc pipe. Likely a little of both, but I know pipe volume should be designed to certain specs for certain displacements. I also don't remember any big change when I modified the 100cc pipe.

To sum it up, the 50-70cc Leo Vince ZX did increase performance on the 96cc engine and it did not cause any heat buildup or engine damage like I saw when I used the MRP 50-70cc tuned pipe. I believe stinger size is the determining factor there. It was right in the middle between a stock pipe and it's 100cc counterpart. Not bad, but I'd definitely choose the correct version if possible. If nothing else, I think this may help to show just why these things are called "tuned" pipes. Two pipes built to the same length and specs other than one having a larger header which creates more volume, and one doubles the MPH increase of the other .

[90GTVert]

I lost an exhaust bolt on the ride, where it mounts to the case. The threads have been less than great for quite some time now, so I finally repaired them with Time-Serts. I made a video of the process. I'm a lousy speaker and the vid will probably bore you to death unless you are interested in an alternative to heli-coils... even then it will probably bore you. Here it is anyway.

[2strokd]

Thanks man! Good to know we can get away with a smaller more common ZX on a bigger engine.

Good job on the serts! LOL, im so cheap i would have put a longer bolt with a nut on the back. And nice pipe mount! They should come with those.

[90GTVert]

Apr 27, 2012 5:49:27 GMT -5 2strokd said:

Good to know we can get away with a smaller more common ZX on a bigger engine.

I'd mainly see th 50-70cc ZX as something to use if you have it around. We'll find out eventually here, but I think the Phongeer that's cheaper than the ZX will outperform at least the 50-70cc ZX. I'm still not sure what's up with the revs though, I really was expecting at least 500RPM more than I'm seeing. If it revved where I thought it should and LV says it should, perhaps both ZXs would do better. The cylinder definitely has the port timings for it. Maybe they do peak closer to 9,000 than 9,500, but I know I used to cruise at over 9,500RPM with a somewhat similar cylinder and engine setup, but a 24mm carb.

[bluesi808]

Great info, I was actually planning on moving from a 70 polini sport to a 90cc and I have a Zxr exhaust. So cleared up a lot of questions for me. Also my exhaust bolts seem to get loose all the time so I'm glad this is probably normal.

[90GTVert]

Fasteners on these scoots have to deal with a lot of vibration and half the time you get bolts cross-threaded from the factory to help you even more. I sometimes use a threadlocker when I'm not swapping so often. I was nice to bolt a pipe up today and not think "please don't strip" when I tightened it up.

[90GTVert]

Phase 4 : Leo Vince GP 50-70cc


The next pipe to be tested is the Leo Vince GP 50-70cc exhaust. I've heard so many negative comments about this pipe that I was reluctant to even try it on Project 90. It's such a great looking piece though, I couldn't wait to bolt it on. Just a note, it does not come polished. I did that myself. You can see before and after pics in THIS THREAD.




This is the version intended to fit a Yamaha Zuma, so it has dents to help it clear the center stand. I opted to leave these alone instead of trying to remove them as I did with the 50-70cc Leo Vince ZX exhaust. This pipe is stainless steel, and I could not repair it myself if something were to be damaged in the process of trying to remove the dents.






I got the pipe with no brackets, but I assume it would not fit with it's stock bracket anyway since the ZX for a Zuma did not. Just like with the ZX, I used a bracket made of 1/4" aluminum and some spacers to mount the exhaust.






Once I got it mounted, I got it in tune. No changes were made to the CVT, and the carburetor used a 100 main jet with no other changes. Here's a video of the GP riding and revving. Please note that while a lot of videos of pipes taken for Project 90 used a stock airbox, at this stage of the project the airbox is more open. It makes more noise, and I think you can hear the airbox more than the exhaust at times. This is a quiet exhaust. It would get more attention from it's looks than it's sound.


www.youtube.com/watch?v=ca63LyBBkgs


I took a 37 mile test ride and recorded 51.67MPG. Max speed was 59MPH at right around 8,500RPM. Cruising speed while sitting upright at WOT was about 50-53MPH at 8,300-8,400RPM. Acceleration improved, and the GP seems to increase power across a fairly wide RPM range. The best power seemed to be 8,000-8,500RPM.




Outside temp for the ride was a cool 50°F. Cylinder head temperature was 270 - 285° riding at 40MPH. WOT cruising showed 290 - 305° CHT.


I didn't expect a result this good after some of the negative press I've read on the Leo Vince GP. It's certainly nothing spectacular, but it kept up with all of the other Leo Vince 50-70cc pipes on the 96cc. In fact, it feels exactly like the SP3 to me. Odd considering the SP3 is often stated as the better of these two street exhausts. From the test results, overall feel, and sound, the GP and the SP3 are essentially the same pipes with slightly different construction techniques to create two different appearances as far as I can tell. They may perform totally different on a 50-70cc setup, but if I shielded you from viewing the exhaust, I don't believe you'd be able to tell there was a different pipe installed from performance and probably not from sound, if I swapped the GP for the SP3 or vice versa on this setup. With that said, the choice between the two pipes would come down to styling and price. If you want a beautiful pipe, the GP wins that hands down IMO. For a more stealthy pipe it'd have to be the SP3. Pricing isn't much of a comparison, sadly. Looking around online it appears a new GP will likely cost about $100 more than a new SP3.

[190mech]

Great info!The GP IS a nice looking pipe..All of the LV pipes would make more power if the headpipes were shortened,they also have a very poor fit in these areas,the pipes are just jammed together and twisted to fit the jig.. :stumped:

[aeroxbud]

The sp3 could well be te GP in a pretty dress lol. For a $100 more i would rather have the SP3 even though it does not look as good, if there is no real performance gain. Plus a tin of vht paint

[lshigham]

I'd pay extra, just because it's shiny!

[90GTVert]

Phase 4 : YMS V8


The YMS V8 is the next pipe up to be tested. I tried this exhaust in phase 2 and wasn't too impressed. I thought that it was better suited to perhaps stock engines rather than those with ported cylinders. For that reason, I almost skipped it in this phase. Since you're reading this, you already know I changed my mind and decided to see if the larger carburetor, intake, and VForce3 reed cage would be of any benefit to the YMS V8. Check out the results of phase 2 in the link below, where you can also see pics, video, and fit info.

Phase 2 YMS V8 Test


I used a 102 main jet and left the W9 needle next to the leanest position. On the test ride, I saw some pretty hot part throttle temps and got some dead spots and even moments of spark knock at certain throttle positions. The needle definitely should have been richened up. As I believe I have said in the past, I don't spend much time on the part throttle settings for these tests. If I don't see any obvious problems on the test ride, I basically just dial in the main jet, make sure it idles well and revs quickly, and select the right slider weight for the CVT. Speaking of the CVT, I stuck with 7g sliders.


I went for a 36 mile ride and got a mere 44.14MPG. I rode quicker and faster than usual (trying to get a ride in before some rain came through the area) and aggressive riding really kills fuel economy. If you want to save gas, stay at low throttle positions. Most of the pipes have been close enough to call them even on fuel economy so far, and I don't think the YMS would have strayed that far from other results with the same riding style. Max speed was 60MPH at around 8,600RPM. WOT cruising while sitting up kept speeds from 51-53MPH most of the time at 8,300-8,400RPM.




Air temp for the ride was 60°F. WOT cruising kept temps around 290 - 305°. Part throttle cruising was a bit tricky from the lean needle setting I mentioned earlier. Part throttle temps varied greatly, some much higher than I'd like to see.


I was a bit surprised to see such a good result after the performance of the V8 in phase 2. I was not expecting it to be more willing to rev than the other street class pipes tested so far. Since it did push slighty past where the other street pipes did at max speed, I gave it a test run with .5g lighter rollers (6.5g). It cruised at about the same speeds as before, while revving to 8,700-8,800RPM. Max speed was 2MPH slower though, at 58MPH. While it was reasonably comfortable at the slightly higher RPM, that's just not where it wants to be for peak output. Acceleration was degraded with the lighter sliders, although of course it would jump into the revs faster. The V8 just doesn't pull as hard when revving beyond the low to mid 8,000RPM range.


I was pleased with the V8's performance overall. It's cruising and max speeds were not far off of the more expensive, louder, and sport level Leo Vince ZX 100cc and acceleration was about even between the two. It nosed by the 50-70cc pipes in cruising and WOT speeds, and acceleration was better than theirs. Not bad at all for a pipe I had discounted and almost didn't test.

[stepthrutuner]

As usual very good advice especially on the freeze dent removal method. The expanded metal surrounding the inside of the baffle is probably not worth removing for a street scoot. Part of my examination of my new chrome TG RSII 70 was running a clothes hanger wire through the pipe from either end bent at various angles trying to determine if there were overlaps at the header/diffuser/dwell/baffle/stinger.... not that I was about to cut apart a brand new $280 chrome pipe. I could not detect any overlaps with this crude method which made me happy. Perhaps TG quality has gotten better. My old NextR had some serious overlaps and I could tell a gain after grinding them out. Most of the noise from tuned 2ts comes from the reeds slapping with a free flow air filter such as a K&N.

[90GTVert]

Phase 4 : Phongeer Exhaust


The Phongeer exhaust is next in line. This one hasn't really disappointed me so far. I wasn't really pleased with it in phase 1, but then none of the pipes impressed me with stock porting. In phase 2 it was my favorite for a few reasons. Check out the links to phase 1 and 2 results below for pics, videos, and more info.

Phase 1 Test
Phase 2 Test


A 100 main jet with no other changes put the carburetor in a good state of tune. The engine was revving to nearly 9,000RPM just cruising with the 7g rollers that the baseline and other street style pipes have used, so I tried some other weights. I ended up using 7.5g sliders for best results.


After the engine and CVT were tuned, I went for a 39 mile test ride. Fuel economy was 54.61MPG, a couple MPG better than what we've seen with other exhausts in phase 4. I stuck with the same riding style that has shown consistent numbers (again the poor economy with the YMS was a result of hard riding). I believe the increase was a result of the ability to remain at lower RPM for in town riding with the heavier rollers, because cruise RPM stayed pretty similar. Max speed was 61MPH at about 8,700RPM. Sitting up at full throttle I could cruise at 52-54MPH at 8,500RPM or so.




The temperature for my ride was 55°F. 40MPH cruising at 7,100ish RPM gave me cylinder head temps of 270 - 285°. WOT CHT was 290 - 305°.


The Phongeer did excellent once again. It's speeds matched any pipe tested so far in this phase. It's acceleration was better than any pipe tested thus far. The fact that I had to use heavier sliders to calm down the revs says something about the Phongeer's power output. From my experience, needing heavier rollers or sliders to achieve the same RPM means more power is being made. I assure you that was evident when taking off. The PG makes good power and it's delivered smoothly. Most of the exhausts have a more evident drop off RPM that you need to keep above. The Phongeer makes it's peak somewhere in the mid 8,000RPM range. It doesn't feel so much like it's "hitting" there though. It feels more like you have an overall more powerful engine under you as it starts off strong and just continues to get stronger. Add to that the fact that it's quiet and not an eye-catcher and you can probably see why I think this is a great exhaust.

[2strokd]

Thanks for this! I need a quite stealthy stile exhaust that a 103 can breath through on the street.
How much for the Phongeer ?