Darkside on 300cc chopper

this may sound silly but does the size of the engine and its power has to do anything with the ability to go darkside or not?

some use to say that darkside is for engines with over 50horse power. but how about if the engine is 320cc and it has 23horse power isn't that enough to turn the car tire the same way it turns the motorcycle tire?

i wanted to try car tire on my 50cc moped because the original one broke few times but luckily i didn't have to change it again. now i own regal raptor spyder dd350e-6 which has 320cc engine licensed (or copied) from Honda. originally is has 160/80-16 tyre and i wonder how it will be (if possible at all) to change it with 175/75-R16. the circumference is almost the same so does anyone has any experience with going darkside on such a small chopper?

your thoughts would be greatly appreciated

Nikola

Heheh...first off, I'd expect a bike that small may actually feel the difference magnified: loss of takeoff, more crossover effect, and disastrous handling on uneven surfaces.
Secondly, if you can find a 175/75/16 now you be sure to let us know. There are a whole lot of us looking for them now that the Comtrac is discontinued.

quadancer wrote:Heheh...first off, I'd expect a bike that small may actually feel the difference magnified: loss of takeoff, more crossover effect, and disastrous handling on uneven surfaces.

please explain what you mean by loss of takeoff (i know what it means i dont know WHY would i have loss). at the moment it takes off even too fast for me since i have ridden it for only 300km (200 miles), i previously rode a pocket chopper 50cc for 2000km.

don't know what is the crossover effect so please explain

WHY disastrous handling? what does the engine size have to do with the handling? *the bike itself is 190 kg (lets say 420pounds)* and i am 100 kg (220 pounds) which makes a total of 640pounds (on the tyre)

quadancer wrote:Secondly, if you can find a 175/75/16 now you be sure to let us know. There are a whole lot of us looking for them now that the Comtrac is discontinued.

They are easy to find here since it is almost a standard mini van tire but i live in Macedonia. most of those peugeot, citroen and other vans use this tire.

for the very end this is my bike:

https://i.servimg.com/u/f61/15/51/40/30/spyder11.jpg

Wow, that's actually ...not laughable - good job!
Crossover effect is what you get going from left/right/left/right, crossing over your centerline. With a MT, you feel almost nothing but the bike heeling over. With a CT, you need to give a little more countersteer pressure on the handlebars to get the bike to heel over. This you get used to pretty quick and don't notice it anymore.
But it's my guess that with a much lighter bike like yours, the tendency to want to stand up straight will be much more, not having the weight to over come the tires resistance to folding. You will also have to run much lower pressures than most of us to keep the tire from standing on it's edges in a corner, which may give you some wallowing; but I admit this is conjecture, as I don't have a light bike to darkside and try it.
You also can't figure ALL the bike's weight on the tire; more like 2/3, since you sit towards the back, engine sits up front. So your possibly 400 lbs on the tire isn't all that much in comparison.
If you are going to any larger diameters, it is an upgearing to the motor and will cause less rpm's, and less power. Since you weigh as much as I do, and your bike is a little heavy for a 300, the extra weight of the tire probably won't affect it as much as I thought.
Still, hitting uneven surfaces affects us even with 1600 lbs. GVW. If it can throw US around, I expect it would be more with a light bike. Possibly much more.

thanks a bunch!

regarding the diameter and RPM-s i am no't worried at all since the tire has almost the same diameter as with the stock one.

according to online calculators the original tire is:160/80-16 = Tire Diameter 26.079; Tire Circumference 81.93.

the new tire 175/75-16 = Tire Diameter 26.335; Tire Circumference 82.73



and since most of the guys change the original sprocket with a smaller one (on the back) to reduce the RPM-s and vibrations i guess i won't have to do that, due to having the same effect from the larger diameter of the new tire.

however the bumps and crossover effects make me worried.

well i guess all that is left is to find a cheap used tire and try it slow speed ... i mean VERY slow speed round the neighborhood and if thats OK then buy a new one and have fun.

once again thanks for explaining!

Nikola

Nicola, I think Quad explained it perfectly. Regarding to the size of the tire you will be fine.
It still looks as a challenge to me, so keep us posted.
Robert.