125i same speed as 200i?

[fshfindr]

My Yager is maxed out at 75mph on my GPS.  Maybe even a little more but not much.

Richard L.

[Wil B.]

My Yager 200 still pulls at 55mph, and is comfy at 60-65mph and maxes out around 70mph (all on GPS.)  Seems stable all the way.  But let's admit this scoot is not designed for highway use.  It should not be ridden WOT for extended periods of time.   I always vary my speed a lot when I'm on the highway and limit such usage to shorter trips.

Even 250cc bikes are not necessarily made to cruise all day at the top of the rev counter.  I've known several folks who blew the engines on their Honda Rebels during long trips.

I'm sure no matter what the stats are, the smaller engined Yager would feel more strained at the higher speeds than our 200 (really 170cc) machines.  And like I said, the 200 pulls very nicely up to 65+mph.

Wil B.
Broadview, IL

'71 Guzzi
'91 Nighthawk
'10 Kymco Yager 200gt
'04 Kymco Super 9

[fshfindr]

My Yager has hit 75mph on the GPS.  On a level road with my 210lbs, 75mph with a little throttle left.  Yes I was over the red line by close to 500RPMs.  I agree that it should not be ridden WOT for a long period of time.  As soon as I realize that I am over the red line I slow down.  All that I am saying is that the bike has these capabilities, not that you should do it.

Richard L.

[Wil B.]

Ha! Richard I've got 20 pounds on you.  Maybe that has an effect???!!!!  Or is it my wind resistance?

Wil B.
Broadview, IL

[MotoRandy123]

 While in studying the service manual it seams the differences between the
125 and 200 are in the drive belt width and rear driven pulley spring.

 So changing the belt on your 150 to the 200 belt might get you some top end.

The pulleys in the manual didn't look to be worn all the way out to the edge so
maybe heavier rollers or a fuzzy washer could do something for the performance
envelope?

  Mine only does about 60 MPH but I'm told it might break in and go a little faster.
I was hoping for an easy 65 and pushing it to go a bit faster....

The tolerances in the pulley setup are small. 0.5mm's can make a difference.
Has anyone ever blueprinted their drive setup before? A burr here or there could
limit your top speed...

[ScooterWolf]

I just completed a 2 hour drive on my Yager hitting a top speed of 66 MPH without trying and just a small nudge above the low end of the red line. I felt like I could easily take her up to 70 if I needed to.

The Yager isn't a 200 cc bike, but a 175 cc.

http://www.kymcousa.com/showroom/scooters/yager200i/specifications.html

- Wolf

[MotoRandy123]

Hmm, I must have gotten a slow one as I just got back from  1/2 hour ride and
cranked it up on the 55 MPH road back and only hit 62 and that was difficult as
I needed to tuck in a bit. Not sure if it's aerodynamics working against me?

The computed theoretical maximum is 67.93 MPH at 8000 RPM's or 109 KPH based on
the variator overdrive reduction of 0.8 and final drive reduction of 8.48 and my rear
tire circumference of 61".

It does great from 30 - 50 but runs out of steam on the top end.

 Maybe I got a 125 belt?

[Cortez]

Tires and inflation, altitude, fuel, how big the rider is.. everything is involved, and 5mph difference
sounds reasonable to me.

[MotoRandy123]

Well I found this online they're trying to state on a typical scooter how fast
can you go based on HP;

"The easiest way I could find to show and explain these was to find and use an online calculator so you could see the results for yourself. The one I ended up using was this http://www.rbracing-rsr.com/aerohpcalc.html.

If you enter the figures I gave you already so 1.0 for Cd and 6.02 for frontal area plus a weight of 428 lbs which is about the weight of a Gilera Runner with a 12 stone person on it. Then you put the speed which you would like to go, or are interested in finding out the bhp needed, you should get the results.

Here are some results and what sort of tuning you would need to get there.

30mph = 1.64bhp. Much less than a restricted 50cc which normally have around 3.5bhp.
40mph = 3.52bhp.
45mph = 4.82bhp. The 45-50mph bhp figures are about spot on for a de-restricted scooter which can range from 4.5 to 6.5.
50mph = 6.47bhp.
60mph = 10.94bhp. Getting into the sport 70cc kit bhp figures and also 125cc 4 stroke bhp specs and 100cc's.
65mph = 13.76bhp. More like the Mid race 70cc kit bhp and the stock 125cc 2 stroke bhp.
70mph = 17.05bhp. A 125cc with just a 172cc kit fitted is around 17bhp and you will now start seeing the bhp figures increasing a lot for not much more mph.
75mph = 20.82bhp. A 172cc with pretty much all the bolt ons.
80mph = 25.05bhp. A street ported 172cc bike with all the bolt ons is around this.
90mph = 35.41bhp. Now you are talking some serious porting and hardly any reliability without a lot of maintenance. Pretty much a sprint bike.
100mph = 48.23bhp. Not even a figure that is reachable by tuning a scooter without nos.

The findings seem to totally agree with what I have found personally when riding scooters and what others have when not referring to the totally inaccurate speedos."

So with our 15Hp we should be able to do 65....

[LoveMyKymco]

I hit 82 mph on my 72cc 2t MHR build. I guarantee my fuel mileage is considerably less than the 200/175s tho. I still had more rpms to go but felt unsafe doing this on a 62 mph rated tire.
Weight definitely effects top speed. Same engine on my kymco zx50 frame I can only hit 76 mph and can not hit the same rpm, I have it currently on a 89 honda elite frame no body work etc and I hit 82mph on a gps only at 11,320 rpms, still have over 2k rpms to go. So its definitely more drag after 60, just the weight is less. Real world proof, weight effects a lot regardless of low or high end speed. Top speed is determined by a lot, even if you have the gears you still have to have the power to push the weight. I run 6.89:1 gears on a full Mallosi MHR set up, minus the carb its 24mm OKO. Mallosi 25 mm carb is on the way at a cost of 260$
Is the 125 frame different than the 200 frame? If so slap the 200/175 engine on the 25 and itll surely fly.

[fshfindr]

My Yager has hit 75mph on the GPS.  On a level road with my 210lbs, 75mph with a little throttle left.  Yes I was over the red line by close to 500RPMs.  I agree that it should not be ridden WOT for a long period of time.  As soon as I realize that I am over the red line I slow down.  All that I am saying is that the bike has these capabilities, not that you should do it.

Richard L.

I just lost 15lbs, maybe I'll try it again, I might get up to 80.

[Cortez]

A good motorcycle jacket will make more difference.

[MotoRandy123]

I took her out on the highway today and got 65 MPH on the flats
and 70! on a slight downhill. She must be breaking in!