Modern Buddy

hello all, i have a 2012 roughhouse 50, i installed the 70cc stage 2 kit from scooterworks,it started up first try, and ran great until i came to a stop, and tried to accelerate. it was slow going until after reached 25mph and then it kicked up to 57mph pretty quick. i had 6.5 gram rollers, 1000 rpm contra, 100 jet, 70 big bore, prima pipe, i weigh a wopping 260. i tried 8 gram rollers and instantly couldnt go over 15mph uphill. i have the roller kit so i can do different variations, i also did 5 gram rollers and it did the same thing just not as soon as the 8 gram rollers. i think it has something to do with the belt not engaging fast enough. if there are any suggestions that would be great. thank you in advance.

Could be jetted lean/rich. It might have run good at first because of the autochoke if it was lean. I'd suggest checking the plug.

I thought the 95 jet was for the Pipe and 70cc kit.

Definitely check the plug.

As for the transmission tuning, you will have to balance it to the new powerband. I did a lot of reading over at 50ccscooter.com for tuning tips.

There really shouldn't be a reason why it is acting the way it is. Maybe something came loose in the transmission?

Your speed issue seem's to indicate your rollers still need tweaking. 5's to light and 6.5 to heavy. Only thing left to try is 5.5 or 6.

Thank you so much guys on the replies, I apologize for the delay in response. I have the set up as follows: I put on the heaviest minarelli clutch springs yellow, moved the rollers back down to 4gram, I have the 1000 rpm contra spring, and haven't yet received the 95 jet so am not able switch those out at this time. I have a 90 but don't want it too lean. The scooter doesn't have the original issue. Although when I first start my execleration, I get sputter, but not the complete power loss as before. And on hills its back to normal. I have a guy coming over to help fine tune, but as for now I think my recent problems are cured. Oh and the white of the spark plug is a nice coffee color. And the ring is not to black. I will continue to explore. I haven't seen many posts about the rough house and what complete set ups work so i hope this adds some transparency to the "hard to mod" roughhouse. Thank you again for all ur help.

I'm running a 95 jet with just a pipe and air box mods(7 1/4" holes and snorkel pulled). Plug is also creamy coffee colored. I was running 4.8 gram rollers and stock contra. Scooter ran strong but RPM was excessive. Currently have 5.6 grams in and I get a noticeable loss in power at 25 mph when it "shifts". I'm going to try 5.3 grams next or maybe a 1500 rpm spring and 5.6 gram weights. I'm thinking about a different variator as the shift is annoying.

I'm wondering... if you have the roller kit, have you tried going with staggered weights? like a set of 7/8s mixed with a set of 4/5s? Tuned just right, you can get max acceleration out of staggering weights.

The other thought, it could be a bit lean... I know the more you mod the scooter, the harder the fine tuning you will find. Curios what your carb is. If you haven't changed it, and have done all the other work, you may be starving your engine for more air at low revs. I'd recommend at least a 19mm Malossi if you haven't.

Hello all, I just had a soft seize on my engine. I just got done installing the k&n air filter, didn't up jet. It had a 100 jet in there. And I was going down the road and it stalled a couple of times. I was thinking crap, too lean. And sure enough when I removed the cylinder head, the rings had fused right to the piston. I am gonna try 115 main jets and higher pilot jets. I know that my carb is small and I will need to make the investment later to get a bigger one. I'm not mad that this happened because before I bought this thing I knew nothing about 2 strokes, and every mistake is a great learning experience for both my kids and I. Thank you for the help everyone

One thing I learned with other 2Ts like this one... once you have done BBKs and other mods, you are going to starve your engine for oil. What I like to do is keep the normal amount of 2T oil in the oil feed tank, but add a few ounces extra to the gas mixture as a just in case. The right mix is going to depend on how you want to run it, just use some high quality synthetic and you should be fine.