Tuning the Forza 300 CVT

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Re: Tuning the Forza 300 CVT

Post by robertinino »

the best answer may give by bred........
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Re: Tuning the Forza 300 CVT

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buon natale
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Re: Tuning the Forza 300 CVT

Post by leoper »

Mario :
cost for tech pulley clutch ?
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Re: Tuning the Forza 300 CVT

Post by supakijku »

In Thailand, they modify Throttle Body by increase the size of Throttle Body. Without tuning ECU, will this actually improve performance?
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Re: Tuning the Forza 300 CVT

Post by Oyabun »

supakijku wrote:In Thailand, they modify Throttle Body by increase the size of Throttle Body. Without tuning ECU, will this actually improve performance?
Kijku, I can't see thisbas a CVT upgrade. I believe you should probably start an engine tuning thread for this. As far as I understand not many performance mods have been discussed for the Forza so far.
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Re: Tuning the Forza 300 CVT

Post by TechFrog »

Hello old friends. I thought I would wake this thread up with a Dr. Pulley update. Much of what I'm posting has been rung through the ringer, but I feel like adding my thoughts. At this point I own both a 2014 Forza 300 and a 2015 PCX 150, having just sold a 2013 PCX (which are slightly faster on top end (different story for another time)). I used to own a very quick Piaggio BV 330 and the biggest disappointment moving to the Forza was the power. After reading forums and watching a few videos, I thought to try some sliders. For the PCX, I simply got 13g Dr. Pulleys and now my rev-limiter cuts me off at about 67.5MPH as opposed to about 63 with the stock rollers. Overall, a perfect scenario and that 4.5 MPH make all the difference on the short freeway runs I take now and then. (Traffic flows at 65 normally here in Los Angeles) As for the Forza, I really had no problem up top, but rather the sluggish acceleration. I got a set of 19g sliders and 17g sliders so I can mix them up and see what weights or combinations I like. My instinct told me to mix the 19's with the 17's and that's what I did. My goal was to run in the torque band during acceleration and maintain the same RPM at higher speed. WOW! What a difference this combination makes. Although many of you have read many pros and cons of lighter vs. heavier, let me simply give you my perspective.

At first, I thought I would think this combination would rev the engine too high during normal operation. That can result in lower MPG. Although we shouldn't worry too much about MPG on a scooter since it's so cheap to fill, my reasonings are for range. I love going about 200 miles between fillups and didn't want to lose that.

My findings:

Yes, the Forza revs higher at lower speeds. During full throttle, it quickly revs to about 6500 - 7000 RPM (in the powerband) where before it held about 5300-5500 for far too long which is well below the powerband. These lighter sliders are still heavy enough to fully close up the variator at highway speeds, so for those that don't quite understand, just know that your top "gear" is still retained and actually slightly taller, so no compromise here. Before, the light would turn green and I would twist anywhere from 50% to 100% for enough to stay ahead of normal car acceleration. Now, I can do the same with 25% to 50% and scream at 100%. There is no comparison. Zipping around mountain twisties and climbing hills are now much more fun as there is so much more throttle response. The bike simply surges forward with each twist. Top speed is nearly the same. Getting there is much faster now.

So those are the pros. Are there any cons? From my perspective, no. I thought I would lose MPG but the last 3 tanks of fuel have yielded me 68MPG, 66MPG and 68MPG respectively. That is nearly the same or slightly better than before. I'm using US Gallons since I'm in the states. So I have retained my 200-mile range and feel like I move from a 250 to a 400. I am so pleased with the first combination, I'm not even going to experiment with other weight combinations.

I had to scratch my head slightly because the MPG seemed to actually increase. The only conclusion my buddies and I came up with is the fact that the engine is running in a more efficient (torque) zone much more of the time. The engine breathes easily. I know many smog standards must be met before they can sell these, especially here in California, so I'm convinced they slightly de-tune the bikes to meet emission and sound level requirements and that likely creates compromises like these.

I know many of you have already done some mods, but if some are still thinking about it, this is not an expensive install. If you don't want to mix weights, meaning you must buy two sets, then simply buy a set of either 18g or 19g sliders and about a 30-minute installation you'll have a much more fun machine.
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Re: Tuning the Forza 300 CVT

Post by gn2 »

As far as I can recall, peak torque on the Forza 300 is around 6500rpm so having the engine in that range will yield the best acceleration.
Fuel consumption was most affected by wind strength and direction, it could drop quite significantly into a headwind.
Three tankfulls perhaps isn't a long enough test?
Four decades on two wheels has taught me nothing, all advice given is guaranteed to be wrong
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Re: Tuning the Forza 300 CVT

Post by TechFrog »

If peak torque is around 6500rpm, I might just give a test with all 6 19g sliders just to drop the RPM a tad and see the difference. I will likely wait till I get past about 1000 miles before I document any findings just to be thorough in my testing.

I'll, of course, keep monitoring my fuel economy, but I also live in a windless city, so only on very rare occasions is that ever a factor. Also, please trust me, gearing can indeed affect fuel economy. I've ridden motorcycles for 35+ years. I changed my drive sprocket up one tooth on a VStrom I owned and increased my range by an average of 22 miles per tank. Tested over 6 months since it was my regular commute. Of course, I lost some off-the-line performance, but that was a fair trade-off for my riding at the time.

I'd like to add, even if I lost 10-15 miles per tank with this configuration on the Forza, the enhanced acceleration, responsiveness and overall rideability is well worth it. So far, on my current tank, I'm on track for about 190 miles it seems. Slightly less, but this last tank was 75% freeway at average 65 -75mph with my 47 liter Givi top case which always reduces my range a bit.

And Bred, if you're still out there, thanks for all the testing. ]

Cheers all
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Re: Tuning the Forza 300 CVT

Post by BRed »

TechFrog:
yep I'm still around even though I traded my Forza for a 6 year old unsold NT700 just for an upcoming cross country ride...
I still think the Forza would have made the 4000 mile trip without issues, but I would have been the smallest bike on the ride by a deficit of 300cc or more.
I didn't want to be the constant lowest common denominator of the ride so decided to trade up to a 650 sized bike.

At any rate with a few thousand miles on it now I have come to love the NT (Deauville?) almost as much as the Forza, but I still miss the Forza's light nimble handling and balance.

I still have two Honda 250 scooters and both are running mixed weights...
I think you're on the right track...the lighter weights put the Forza closer to it's prime power band and it requires less throttle under most road conditions.

Remember what 3 rollers can bring to your slider mix....
a higher (taller) initial gearing than that of sliders and a quicker, more positive downshift at roll-off.

Try them...you might like them? ;)
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Re: Tuning the Forza 300 CVT

Post by TechFrog »

Hey BRed, I can't even imagine the variator being better than it is but I trust you. As for your NT700, congrats. I have always loved that machine and have always kept an open eye for a good deal, but my only wish was that it had a 6th gear. I was looking at NT700's as recently as a month ago and there are still a few good ones out there. I also just picked up a 2004 Helix with less than 6000 miles on it. Couldn't pass it up for 2k in showroom condition.

At present, I have a 2014 Forza 300, 2015 PCX150, 2004 Helix, 2013 NC700X and as implied, I still have my eye on those NT700's. I'd love to hear your input on any limitations you might have found having only 5 gears.

Want to stay on topic in the thread so I'll add to my fellow Forza peeps, that I'm on about the 8th tank of gas since the sliders and yes, I'm still getting near, or just over 200 miles per tank.
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Re: Tuning the Forza 300 CVT

Post by E. Foster Salsbury »

Thank you Big Ruckus Ed for posting your extensive test results.
I just bought some Dr. Pulley sliders 23x18 18 gram because of your research.
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Re: Tuning the Forza 300 CVT

Post by sendler2112 »

gn2 wrote:As far as I can recall, peak torque on the Forza 300 is around 6500rpm so having the engine in that range will yield the best acceleration.
Fuel consumption was most affected by wind strength and direction, it could drop quite significantly into a headwind.
Three tankfulls perhaps isn't a long enough test?
Peak torque or just below will give good fuel efficiency. Peak HP will give the fastest acceleration.
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Re: Tuning the Forza 300 CVT

Post by BRed »

Salsbury, I'm glad you found some useful information in all those graphs!

TechFrog, it's been my experience that when a rider says this bike or THAT bike, needs another gear, it's usually the rider and not the bike, who really needs another gear. :)

The NT700 and your NC700 are perfect examples of divergent engineering....
both have almost identical displacement with twin cylinders, but they achieve it by reversing the bore/stroke ratio, giving each bike uniquely different characteristics.

The NC700 is an undersquare design (long stroke) with stroke greater than bore...
basically, a low revving engine making peak torque around 4800prm and peak HP at 6000rpm with a 6500rpm rev limiter.

The NT700 is an oversquare design (short stroke) with bore greater than stroke....
the NT makes peak torque at 6900 rpms, 400rpm PAST the NC's rev limiter and it makes peak HP nearly 3000rpm beyond the NC's rev limiter.

Whatever the NT lacks in gearing, it more than makes up for it with abundant revving headroom.
At any speed under interstate speeds, you can literally chose your gearing...if you don't mind the vibes!

The NT in 4th gear can manage 90% of all driving situations I can imagine (exempting Interstate speeds)...it can drop down to 20mph and easily reaccelerate without downshifting. Riding in mountains curves, I found I could run third gear continuously and use the throttle like a speed controller, using the engine's compression braking to shed speed in corners almost as fast as it could gain speed in the straights when rolling on the throttle.

I would say the main difference between the two Honda 700s is in the feel.....
the NT is definitely more "buzzy" at speed and any attempt to lower its revs near full throttle with a 6th gear would probably result in "lugging".

But, the NT doesn't need another gear...

It is what it IS.

ed
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Re: Tuning the Forza 300 CVT

Post by BRed »

a couple of pics of my newish NT.....

Image


Image

sorry for the off topic drift...........
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Re: Tuning the Forza 300 CVT

Post by homie »

Is it tuned yet? ;)

about the picture... there is something OD that is screaming and I can't see anything else o_O
WHAT IS THAT!!! 8) 8) 8) Do tell about that in other bikes.......... Please!
And can I have it?
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Re: Tuning the Forza 300 CVT

Post by WhiteNoise »

Whoa BRed your newish NT700 is picture perfect, eye candy, just Lovely!
Nicely accessorized. Here's a bike that crys out for hard Side cases and she's sporting them.
Congrats and Ride her proudly! Thx for the pics 8)
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Re: Tuning the Forza 300 CVT

Post by E. Foster Salsbury »

Hey Ed, curious why you measured the sliders at these two points and not where the ramp plate makes contact?

Mine arrived today and when I measure where the ramp plate makes contact I get the same 23.3mm as the stock rollers.


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Re: Tuning the Forza 300 CVT

Post by BRed »

A good question but one you'll be able to answer for your self soon enough.

The slider never actually makes contact at the point opposite the flat where you measured.
The installation drawing accurately depicts this.

all lifting contact occurs on the front half of the slider so there isn't actually a physical point to measure the slider as there is with a roller.

What I did was install rollers of a known diameter and measure the assembled thickness of the variator with thrust plate then compare that to a measurement obtained with sliders installed. What I determined was that sliders are ~.8mm - 1mm smaller than MOST 23 x18 rollers. The point where I measured was the closest measurement to index sliders to rollers.
Test this for your self for confirmation.

I dug up some old slider to help show this....
these were sliders I made by swapping out 24g cores from Honda rollers.


They have well over 20,000 miles on them.


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Re: Tuning the Forza 300 CVT

Post by E. Foster Salsbury »

Thanks for the explanation Ed.

Installed the 18 gram today. Did about 30km test ride. Cruising at 60kph tack is around 4700. Throttle to WFO and it jumps to 6500.
WFO from a stop and it goes to 6500
120kph is 7500.
145kph is 8500

Need to do more km but so far I like them
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Re: Tuning the Forza 300 CVT

Post by BRed »

Be sure to record those numbers....
as your sliders wear in and burnish the bearing surface they will inevitably show a slight change in performance.

After about 100-200 miles of wear, the sliders will start to move out faster due to a reduction of "stiction"...
when this happens you'll notice the revs drop as much as 150rpm for each of your reference points.


This is one of the reasons many CVT tuners get unpredictable results....
they don't have the patience to run each weight modification for a reasonable time to insure the jacket surface of the weights they have selected have actually "worn in".

You should always expect new rollers or sliders to move out at lower rpm after they wear in....
in effect they act like they gain about 1 gram of weight and so give a small decrease in acceleration as this happens.
It is a small but detectable effect.

The same is true for springs, like a contra spring or clutch fly-weight springs....
as they wear in, they become "softer" and their dramatic effect on take-off performance, becomes a little less so.

all these effects go undetected if you only try each weight or style or combination of slider or roller for 10 miles or even 50 miles....
give the mod a fair chance...and RUN IT!

if you're using brand new components, you'll see their performance gradually slip for up to 200 miles, then stabilize for the next 25,000 miles or the remainder of their useful life.
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