So, how'd that engine mod work out for you?

[Valiant]

I thought it was going to be a simple install, but they had to tear it apart Q_Q

[dasshreddar]

Big bore kit and wiring not so simple...
How much is labor going to cost you?

[Valiant]

Well, the estimate was around $200, but that was when they expected it to be done by Monday . I don't believe either of us thought the whole thing would have to be taken apart, but there ya go.

In any case, I'm sure it'll still be cheaper than the almost $600 my dealer charged me to swap out the exhaust, variator, and do a basic oil change .

[dkazzed]

Wow Valiant, would like to see how this goes.

I'm sorta thinking of sourcing a 150cc engine from the Asian market Honda CBR 150Rs. Not that i need the extra HP, but it would be nice.

[Valiant]

Wow Valiant, would like to see how this goes.

I'm sorta thinking of sourcing a 150cc engine from the Asian market Honda CBR 150Rs. Not that i need the extra HP, but it would be nice.

Not very well at the moment.

The 31mm Throttle Body I was sent didn't include the larger intake pipe to connect it to my airbox, and the 31mm manifold didn't include the insulation piece, so there was just two o-rings rubbing against each other with metal-to-metal contact. As well, the mechanic tried to straighten the pieces out to see if it would run, and found that the fuel mix was way too rich.

At the moment, I'm not sure if it would run properly even with the missing pieces, as it sounds like the fuel mix was richer with the TB than without it. I'm not sure if the lack of a proper seal would cause a shortage of air, as I would assume the engine would simply suck air from the space around it rather than the airbox, which is more of a problem with the panels on.

There's also issues with the Enigma EFI unit I bought, as I thought it would either have a fuel logging function or come with pre-made maps, but that wasn't the case. So right now, it's basically in a state where it wouldn't do anything different than using the stock ECU, and I don't know how to adjust it.


So yeah, not going as planned .

[Pcxdemon]

Measure the Tb outer diameter, then take the stock intake manifold hose to the local auto store and match it up as close as possible to one of car/truck coolant hoses. Then enlarge the hole in the box to fit it in and connect it to the Tb. I'm pretty sure there are no intake manifolds sold by yuminashi as they sell it in mind for customers to install a pod directly on to the tb itself.
With the intake manifold between tb and the head, you have to reuse the original gasket that sits between the two but install new rubber seales provided. I'm sure as I remember from mine, the port is still same size but the new tb manifold is mirror polished for optimum speed flow..

[Valiant]

Actually I'm 99.9% sure that the parts I need are right here:
http://www.yuminashi.eu/big-tube-air-intake-set/
http://www.yuminashi.eu/insulator-o-rin ... cx150-led/

It's just that I'm not sure if it would work even with those parts and a correct fit. As mentioned, the mix was running rich, and I'm not sure if the fit of the parts contributed to that. Because originally, Roman had the thought that the OEM sensor block wouldn't work with the new TB, so he sent another one. If the injector is firing off too much because the sensor isn't compatible and is sending bad feedback, then I'd be shelling out another $100(most of it international shipping) for nothing.

[Valiant]

Alrighty!

I've got my PCX back, dead late at night, so no pics(only thing new that would show up is the Givi windscreen and my adjustable brake levers).

The kit is installed along with a larger injector, but I'm still currently using the stock manifold and throttle body. Thankfully, Reggie from Yuminashi has now given me a quick response(within an hour, thanks Reg ), so I'm confident that try #2 will work.

First impressions on 35 mph speeds:
The gearing is longer for sure. I went from 13g rollers to 10g rollers, but there's a very noticeable lag(2-3 seconds) at around 10-15 mph(there was no lag before), which then "jerks" afterwards. Definitely more power, it's not even breaking a sweat at low speeds, and very quiet too(which is a little unusual with the aftermarket exhaust and derestricted intake). Tach was not installed(they forgot about it), so I don't know what rpms it's pulling at. Speedo seems to work fine, they didn't have to do anything to it.

Regarding the lag, the mechanic recommended I get lighter weights and stiffer clutch springs(not the center). The fuel mix was tuned to the extent they were able to short of taking it onto the highway, so I'm not sure how that's going to work out. I was assured that it's perfectly safe to ride, just that it might not give the best performance given what I put in it. I suppose I'll grab the Bazzaz combo if my fuel economy drops into the 60s.

[Valiant]

Okay, so I got to give it a good run today...
After about a minute of trying to get the thing to start up Q.Q

And what I mean by that is that I tried to start the engine, which it did, and then it stopped 3 seconds later. Tried it again, same problem. Tried it again, but gave it a little gas, died before it could rev up. Then I kept my thumb on the starter for about 10 seconds and it went into a stable idle. Was pretty damn weird, but it didn't bug me again for the rest of the day.

First, the obligatory eye porn:



Windscreen makes a huge difference for me. Noise is up slightly, but a headwind no longer blows me around, and I don't notice as much wind resistance. The brake hose, pads, and adjustable levers, not so much. It might just be that I won't notice it with sub 30 mph quick stops, but I just don't notice a huge difference in stopping power.

Speed-wise I don't believe it went much faster despite the longer gearing. Speedo indicates 74+ mph, GPS insists it's 69 mph. GPS reading was always conservative, so I'd say the speedo is accurate for the most part, maybe over-reads by 3 mph or so, which is better than under-reading. One notable thing however is that acceleration is way up. 0-60 is 10 seconds or less.

I can now cruise on the privileged left lanes without trouble keeping up at all, if anything I'm catching up to the cars in front of me. I would say acceleration doesn't quite "bottom out" until about 65-70 mph on the speedo.


I expect it'll be another month or so before I have all the parts necessary to run the complete setup including the 31mm throttle body and 31mm manifold. I've ordered a Malossi Delta Clutch set(includes their wing clutch bell) and clutch springs, which should eliminate the lag at the low end(total PITA). I'll try running lighter weights as well, because judging simply from the engine noise, I don't think I'm producing the rpms at WOT.

[Valiant]

https://www.youtube.com/watch?v=RLqpxK4zu-U

Video uploaded! Just a little hop on the freeway.

[Branyers]

I have upgraded my clutch, drive face, drive belt, variator and torque driver. With all of these mods, the bike takes off like a banshee and is very confidence inspiring. Top speed is 75mph+ depending on conditions.

If you don't like to work on your bike, that is fine. But don't lambast others for trying to get a little more out of a bike that otherwise suits them perfectly. Would I like a Forza? Absolutely. But I also do not have the room or 6 grand to shell out on a bigger scooter. Oh, did I mention I like to work on my bikes? It would be boring if I bought a Forza because the only thing I would do to it would be adding accessories. People mod their machines for better performance. Deal with it.

[Valiant]

Alrighty, so I took her for a little spin about 25 miles away from Honolulu to Kaneohe along the H3(60 mph speed limit, fastest zone on the island). On flat roads I'd say she can go about 70-75 mph if there's enough room up ahead to accelerate. On the windy uphill valley I was pulling about 60 mph, though I'd say I could go a bit faster maybe to 63mph if there wasn't a car in front of me. Because I was already at full throttle, I wasn't able to pass on the left(because it would take a full minute to do so, and I doubt anyone has the patience for that). That being said, 60+ mph on an uphill is hauling ass when my stock speed up that same path was 47 mph.

Downhill got interesting, as my speedo insisted I was at 80 mph for a brief moment. GPS says I was going 74 mph, but it usually doesn't register my speed unless I hold it for 5+ seconds. My 0-60 speed actually takes about 15 seconds or so. I assume that's largely because of the longer gearing outweighing the drop in roller weights(from 13g to 10g), causing pulling rpms to drop. I feel acceleration is up from 50-70mph, which is likely where the PCX is at peak rpms(8000-8500).

When I was done for the day(also went around Diamond Head, so about 40 miles total), I took a picture of my gas usage:

Was topped off before I went, fuel economy was 86.7 mpg when I spent much of my time at 60 mph or higher. Previously my fuel economy was about 82-83 mpg. So I'd say overall I gained top speed, hill climbing power, and fuel economy.

Not too bad given my lack of a throttle body and manifold(the 31mm intended to be used with the kit). It'll be interesting to see what would happen with that number with the complete setup. Right now it should be running a little rich all around, but lighter weights and the Malossi delta clutch might cut into the fuel economy, especially at lower speeds. Ultimately I think the gearing would keep it neutral relative to where I had it(82-83mpg) prior to the install.

[Pcxdemon]

Hey that's what all this time I said..top speed up, acelaration up and mpg same if not better than 125cc.
Now comparing to you, which by the way we have same top speeds (GPS and speedo..) I get 0-60mph in low 9's and few times at late 8 seconds time..now that's hauling ass!

[Valiant]

Well, hopefully that 0-60 speed will get better when I get the parts in. Might be late April before that happens though. On the other hand, I haven't had any problems with the engine dying on me, so that's always a plus.

[Valiant]

Another interesting thing to note:
Prior to the BBK install, I had an aftermarket air filter, removed the snorkel from the airbox, and a Takegawa Power Silent Oval exhaust.

I noted that sometimes when decelerating I would hear a popping sound from the exhaust. Didn't think much of it until I had the BBK install and noted that it doesn't pop anymore and the overall engine noise went down. A quick Google search shows that it was running lean prior to the BBK install, and is currently running rich. I haven't noted any problems other than the popping sound, so it might just be that the engine was running lean momentarily on the idle. Still, something to consider before slapping on a shiny new exhaust and pod filter.

[Pcxdemon]

That's why takegawa and others offer efi piggy back to adjust fuelling for stock injector.

[dasshreddar]

Alrighty, so I took her for a little spin about 25 miles away from Honolulu to Kaneohe along the H3(60 mph speed limit, fastest zone on the island). On flat roads I'd say she can go about 70-75 mph if there's enough room up ahead to accelerate. On the windy uphill valley I was pulling about 60 mph, though I'd say I could go a bit faster maybe to 63mph if there wasn't a car in front of me. Because I was already at full throttle, I wasn't able to pass on the left(because it would take a full minute to do so, and I doubt anyone has the patience for that). That being said, 60+ mph on an uphill is hauling ass when my stock speed up that same path was 47 mph.

Downhill got interesting, as my speedo insisted I was at 80 mph for a brief moment. GPS says I was going 74 mph, but it usually doesn't register my speed unless I hold it for 5+ seconds. My 0-60 speed actually takes about 15 seconds or so. I assume that's largely because of the longer gearing outweighing the drop in roller weights(from 13g to 10g), causing pulling rpms to drop. I feel acceleration is up from 50-70mph, which is likely where the PCX is at peak rpms(8000-8500).

When I was done for the day(also went around Diamond Head, so about 40 miles total), I took a picture of my gas usage:

Was topped off before I went, fuel economy was 86.7 mpg when I spent much of my time at 60 mph or higher. Previously my fuel economy was about 82-83 mpg. So I'd say overall I gained top speed, hill climbing power, and fuel economy.

Not too bad given my lack of a throttle body and manifold(the 31mm intended to be used with the kit). It'll be interesting to see what would happen with that number with the complete setup. Right now it should be running a little rich all around, but lighter weights and the Malossi delta clutch might cut into the fuel economy, especially at lower speeds. Ultimately I think the gearing would keep it neutral relative to where I had it(82-83mpg) prior to the install.

Valiant, I know the "H3" you are talking about, 60mph up that on a PCX is impressive...
How fast can you go on the center stand now?
You might be able to get above the 74gps but you probably would have to hold that 80speedo speed for like several seconds...
Some of my gps speed testing has taken upwards of 30 seconds for all the satellites to link up.

[Valiant]

Valiant, I know the "H3" you are talking about, 60mph up that on a PCX is impressive...
How fast can you go on the center stand now?
You might be able to get above the 74gps but you probably would have to hold that 80speedo speed for like several seconds...
Some of my gps speed testing has taken upwards of 30 seconds for all the satellites to link up.

I only tested that for about 5 seconds, during which it went up to 80 mph. The reason I stopped was because it vibrated enough to move the PCX sideways even on the stand, and because there was a sudden heavy stench of gasoline. It might also be worth mentioning that I was running it on the stand right before the engine started to die out.

[dkazzed]

That's awesome Valiant!

[Valiant]

Video.
https://www.youtube.com/watch?v=csRrOzqe7wA

7:35 is where I merge onto the H3. From there I'm at WOT going about 60 on the speedo. As you can see, cars are blowing by quickly on the left, probably going 70-75 mph. I never attempt to pass on the left because the PCX is struggling to stay above 60 as it is.

20:27 I decided to skip over to the right lane instead of waiting(more) like a retard for the light that never changes. Judging from the time, it took over 20 seconds to get up to 60mph.

26:20 I pushed the PCX to just barely touch 80mph on the speedo briefly before slowing down for the curve.

Overall I think I'm pretty happy with where it is. It clearly doesn't have enough power to match your average sedan on faster highways if both drivers are pushing it, but I think I can safely say that this is the most fuel efficient freeway usable vehicle at 86+ mpg.