Polini big bore kit for 2011 super 8 50 2t

[Geehun]

I'll be picking up my 70cc big bore kit tomorrow. And will be installing it. I have some questions. What weight rollers should i get and how big jets should i get? Currently mods on the bike are removing tube from airbox and welding the 2 ports on the exhaust to eliminate the recirc. Also have removable screw on exhaust pipe.

It would be great to get some answers by today. I dont want to make back and forth trips to the store.

Much appreciated.

Anthony

[Peters]

Hard to say. I'd go ahead and buy a roller tuning kit. It comes with lots of different weights so you can find what works best for you. Once you do, you can order better quality ones in the weight you need. They will last longer. Weight of the rollers depend on the roads you ride on, riding style, and how much you weigh. Go ahead and get a yellow/1500 contra spring. Change the spring and if you're lucky you may find the rollers you already have are perfect. I also recommend some yellow clutch springs too.

Best thing to do is go ahead and get a bigger carb. Stock exhaust sucks no matter what you do. You'll want an expansion chamber type exhaust eventually and you'll definitely need a new carb with that. I'd just go ahead and bite the bullet on the carb. Dell orto 19mm carb is a great choice. You'll find it in a Malossi kit. Comes with everything you need.

As far as jetting same thing goes as with the rollers. There are a lot of variables when it comes to jetting and it's hard to say exactly what you need. Best thing to do is start way big and work your way down one jet at a time. Do a google search on "how to do a plug chop".

[Geehun]

Thank you sir.

[Peters]

No problem 

Sorry I went back and edited my post a little. Added a few things. Didn't think you would read it so quick 

Good luck 

Let us know if you have more questions

[Geehun]

alright thanks. Was going to just start with big bore kit first. Works slow so can really spend too much. It's pretty straight forward for the bore kit right?

[Peters]

I understand. Just wanted to prepare you for what's about to happen  . We call this the performance bug on here. Once you start, you can't stop  . Happened to me... In all seriousness, you will want a nice exhaust eventually. Especially with the BBK. Exhaust will increase HP, torque, and depending on the pipe you chose will bring the power band up around 8500 to 9500 rpms. It's really almost a must with the BBK. But, you don't have to right now. I understand. I know that Polini kit wasn't cheap.

straight forward?

Yes and no. I'm not familiar with the Polini kit but I know it's one of the best. You can spend a lot of time polishing all the ports, chamfering all edges especially the exhaust port, and making sure the squish band is right. It will last mush longer as well as perform better. I wish I had done all that. I just threw mine on. I haven't had any issues but still.

After you do get the cylinder installed, it's extremely important you get your jetting right. Rich is ok but lean will ruin that quality costly cylinder and piston. Ideally you want to be just a little rich. Altitude, climate, time of year, and many other things affect jetting. Just keep that in mind.

[Geehun]

Lol thanks Peter.

I know I will spend lots on the scoot but it's just if the wife finds out, I'm in sh** for spending too much money. I also have a 89 Toyota mr2 sc swapped with a v6 Camry engine. You should see how much I spent. Until work picks up in the fall, I won't hesitate to purchase the parts I need.

Thinking of getting a Leo Vince chamber exhaust. What is bbk? Can you elaborate on that?

Question. Thinking a installing 2nd battery in storage comparent and wiring it in parallel to the existing one. Reason is to add hid. Is it a good idea?

[Peters]

bbk is big bore kit 

Sure you could add a second battery. Hell, I never even use my glove box. Sounds like you've got big plans 

[Geehun]

Go figure

Sounds good. Can the gears be changed? Whats the max rpm i can get with mods? And whats the max top speed i can get?

[Peters]

This may help you shop for exhausts. Won't hurt to go ahead and shop around now, find the pipe you want and then find the best price. If you're like me when you're ready to order you're ready to order.

http://www.tuningmatters.com/2012/05/17/review-the-ultimate-scooter-tuning-exhaust-comparison-test/

Keep in mind these tests are on a stock scoot. A bbk could change the results. Tecnigas RS2 is one pipe actually designed to go with 70cc kits. I have the Next R. Bought it before I put my bbk on. Kinda wish I had got the RS2  

[Peters]

The gears can be changed and there are a few guys on here that have. The super 8 2t is a pretty new model. Not sure if there is anyone on here that has built one up. You'll be our guinea pig   .

With the bbk and some cvt tuning you should easily get 50mph on flat ground with huge improvements in acceleration. With an exhaust and new carb and again more cvt tuning, you should get up to 55+ and again more acceleration.

Tuning the cvt will allow you to balance acceleration with top speed. You can easily get 10,000 rpm out of a 2t. But unless you really go to town on it(like zombie), the power and torque curve will begin to fall off at about 10,000 or earlier. And that's with a good exhaust and open element air filter. With high rpms like that the engine needs to breathe. With stock exhaust not only will it produce less power/torque, it will begin to fall off around 7,500.

[Geehun]

Installed polini bbk and it was a breeze. Tuning was the sh**s.

I bought the bbk and Leo Vince exhaust.  Exhaust was returned because I lost back pressure. Don't use the rollers that come with the exhaust which is 5.7 grams. The bike likes between 8-9grams. With the exhaust my top speed was 40km/h. I stuck with my 82 main jet. Tried 88 and 92 didn't work out so well.

Right now going to keep with stock exhaust and upgrade to the stiffest contra spring and clutch spring for faster acceleration. I really dont need top speed.

[Peters]

Yeah I don't think Leo Vince is very good

Yeah, 40km/h is pathetic. Something's not right.

Don't worry, it never works out the first time. For me anyway. Especially when you're trying to change so many thing at once. Keep at it. You'll get it.

82 main jet has got to be too lean. I'll warn you be careful. Do some WOT plug chops.

Don't know what contra spring you have in right now but the stiffer the spring the heavier the roller weights will need to be. Clutch springs just control take off. I like the yellow ones but it's all a matter of opinion.

Just keep tuning you'll be happy when you get it right. Sounds like you've done your homework so that's good. Let us know if you have any questions 

[Geehun]

I just want to catch up with my brother's vino.

I don't have contra springs nor clutch springs yet. Going to search on ebay for some. I'm more interested in the RED contra springs. Thinking of running 9g rollers.

I can feel a difference now in driving. Start is pretty good, middle range is so so. My top speed on flat is 69km/h. I weight 185lbs so maybe that's why i'm slow. Max speed up hill is 53-55km/h. Down hill speed at 83km/h.

SO you say i'm running too lean, i have a 85 main jet, should i put that in? The spark plug looks brown not white nor black.

Tell me what you think.

Thanks

[Peters]

Contra spring will change everything. I run a red contra myself. I'm around 7 or 8g rollers right now. But, I have a people 50 2t. Not sure if they have the same engine or not. Probably doesn't make much difference anyway.

Your mid range issue may be of because of the needle setting in the carb. Unfortunately the needle is not adjustable in the stock carb. You can find a way to shim it. Wordslinger has. He does it by using aluminum from beer cans to shim the needle up  . I never found a way to get the needle out of the plastic retainer myself. I was afraid I was going to break it.

I weigh about 275 lbs, so I don't think that's the issue

Yeah I think you're lean. I think. I'm not sure. Like I said lots of variables. What was the factory size? Where do you live? altitude? climate? Mine was really small. Like 75 or something like that.

You can not go by what the spark plug looks like. You have to do plug chops. This involves warming the engine up, installing a new plug, and starting it, then immediately running it wide open for a mile or two. When you're done, kill the ignition while keeping the throttle wide open. Let the engine come to a complete stop before letting go of the throttle. Pull the plug and look at the white insulator inside. You want a coffee(cream coffee) color on that insulator. There will be a ring of coloration. The distance from the tip also indicates fuel air mix. You can cut the threads off to get a better look(hence the name "plug chop") Here is a good link
http://www.kawtriple.com/mraxl/carb/plugchop.htm

There is three ranges you need to check. Idle, mid range and full throttle. Idle is controlled by an idle/slow speed jet as well as the mix screw on the carb. The mid range(1/4 to 3/4 throttle) is controlled by the height of the needle as I mentioned earlier. Last, full throttle(3/4 to WOT) is controlled by the main jet. Much more to it than my brief break down so do some research. You can read for days on tuning a carb properly.