My Honda NX125 (CB motor) will do 100 km/h after swapping out the primary driver ratio with 16/50 sprockets (50t is the only available size for the rear).

I believe my tao tao tbr7 did 85 mph in the back of the delivery trailer truck across the entire country. Completely stock in the crate! :-)

Top Speed: 110 km/h (68 mph, GPS-verified).

Bike: 2007 ZongShen LZX200GY-2 (Sierra), 21000 km at the time (1y ago), 25000 km now.
Front/Rear Sprocket: 14/42 => Previous owner obviously modded it for cruising.
Mods: None yet => Just some much-needed overall maintenance.
Carb Tuning: None
Rider Weight: 85 kg (190 lbs, give or take, with gear)


N.B., that top speed was achieved on a perfectly flat straight with no wind. It could probably be pushed a little more. However, at the time I still had the previous owner's Shinko cruiser tires. Heavy, 6-yo, hard as rock and in need of a rebalancing. The front started shaking a bit too much for comfort, so I throttled back a bit. The speedo reading was 130+ km/h at the time.



At the moment I have Pirelli City Demons mounted, with the front being a 3.00-18 (closest available size to the stock 100/90-18). This throws off the speedo readings even more (+10%) due to different diameter, but the bike is much stabler. Cruising at 90 km/h (55 mph) all day comfortably, even in moderate grades with some speed/momentum management. Oh, and of course some good ol' leaning on the bike, Rossi style ;)



The few times I attempted a "top speed" run since I managed 105 km/h (65 mph) and I felt it could go a bit more, but I really don't like pushing much beyond 100 km/h if I don't have to. At those speeds everything counts (even the fuel and oil used), and the motor is approaching its rev limit even with such a tall gearing.


But it's obvious none of these bikes is built for top speed :)

Top Speed: 62mph GPS Verified
Bike: 2015 Veloci Xeverus CB223CC ohc engine.
Front/Rear Sprocket: 16/46 on 130-80-18 rear wheel.
Mods: no performance mods. Stock pz30 clone carb.
Carb Tuning: None yet
Rider Weight: 218 lbs

Sea Level.


Can run a little bit faster but its just feel not very safe, bike has a lot of aero drag (raised 1 1.75 inch on rear swingarm and 50 liter rear luggage.)


59,XXX km chasis, currently on third engine.

Update on my CSC TT250
 

Posted a while back. Previous info: TT250, SS exhaust, Conti GO! street tires, 47 sprocket, VM26-606 carb, pannier "sails", 175 lbs. 66-67 mph.

Noted before that I was switching to a VM28-49. Well it doesn't fit. Too big and it has a huge fuel inlet. Anyone want/need it, I'll give you a deal.

Got a NIBBI PE28 and it is perfect. No difference in top speed, but before I was guessing a 4-5 mph correction factor (70-72 indicated). Now GPS actually does show 66-67, but 75 was the indicated. So, no change sort of, but more accurate.

In normal conditions the PE28 runs better than with the VM26-606; more responsive by far. Runs completely smooth up to 8000 rpm in every gear. 8K in 5th is pretty much terminal velocity unless I am going down hill.

I don't think I would ever want to go any faster on this bike. 66-67 is on the borderline of stability even with the Conti Go! street tires (90/90 front, 120/90 rear). I am glad my commute doesn't involve highways.

Moved the -606 to my Orion RXB150...very nice on this bike...massive improvement over the "Mikuni" VM26 Flange mount that was stock.

30mph so far on the new 125 scrambler. Although I am limited to farm currently as my CBT isn't until mid December.

125's
 

Wish we had the selection of 125's that you have in Europe. Would like to get my hands on an old CG125. Had a 1973 CB125S a long time ago...but sort of like the historic value of the CG engine.

Maybe with the resurgence of smaller displacement bikes (KTM now imports a 200) we will get 125's some day.

2020 Ssr xf250
 

2020 ssr xf250 street
Emissions delete
16t front sprocket and stock rear sprocket
Carb needle moved up one shim
Carb air mixture screw 1 1/2 turns out
Rider weight 205
77 mph on flat
82.7 mph down hill
Odometer 2670 km
Future mods will be 32mm flat slide carb, slip on exhaust and jetting

Going to do some measurements for intake boot to see if can get a 34mm carb in their, we’ll see

Take care