Stella (Star 150 4T) bolt-on upgrades

Greetings all,

I'm a Texas based Stella rider and I'm ready to start adding some performance. If I'm not mistaken, the US Stella is essentially the LML Star 150 4T so I am assuming that performance parts for the Star will work just fine for me. Any comments on that? 

In addition, I'm considering either the Pinasco Symphony exhaust or the Gianelli exhaust for a first step. I expect to need to jet my carb but I'd rather not replace the carb just yet. Any thoughts there? I was thinking Polini at first but have changed my opinion after reading some comments on the boards. We don't have much info on the performance mods here in the US so I'm hoping you guys in the UK can shed a little light.

Realistically, I'm looking for a little more "umph" off the line and more power when climbing hills but I'm trying to keep things limited to weekend bolt-on project level of difficulty. 

hello texas,

have you found out anything else performance wise for the stella 4T? i keep looking to see if Genuine has come out with something for it (under their Prima brand.) but nothing so far. it's a new model so it might take some time.

i believe you are correct about it being the same as the LML Star 150 4T. so the things listed at SIP is about it.

i'm hoping Genuine brings the Star 200i 4T over to the u.s. as a Stella 200i 4T. no word on if that's going to happen... no matter how many dealers i ask. or, how many emails i send.

how do you like your Stella 4T so far? i know a couple of people that have them and they seem to like them. they keep up just fine on the group rides. i took one for a short test drive... o.k. power. and really quiet.

the SIP road style of pipe wouldn't really work to well with the four cycle engine.

to be honest, you will get a little with a pipe, but nowhere near the increase you will get on a two cycle.

the cylinder is definitely your first step for more power. the only part really missing tunign wise for those new four strokes that I'd like to see is an improved head with either bigger or more valves.

just a little update... i sent S.I.P. an email asking if there were any plans for a 4T version of the S.I.P. road exhaust for the stella/star 4T and they replied 'no'. i think it would be a really good idea... stock look with a performance increase and maybe a little bit of a growl to it . lets hope they decide to work on it. or maybe sito will work on something.

Let me qualify by stating my Stella is the new 2011/2012 four stroke model. They stopped shipping two strokes into the US a couple years back. 




the first step is to change the cylinder with this 165cc Kit



next step, add a 22 carb like this:


and than an exhaust makes you fly:










well the stock lml/genuine 4T pipe is a lot like the SIP road style (or stock 2 stoke pipe and a sito+ for that matter.) so i figure someone could come up with a stock style pipe but with a little bit of increased performance and a bit of growl. (a 150cc 4T lml star/genuine stella is very quite.) i know a new cylinder (and head) will give you the most power jump... but i'll take a small easy lower cost bolt-on power jump over having to tear apart a working engine for a bigger power jump. and i believe polini has an exhaust for the 4T but i like the low key stealth stock look.

hello , I also have a Star 4T , this setup looks great , I am going to order all the polini parts . what air filter will work best with the 22mm carb and will i need a jetting kit ?   Thank You !

i couldn't find it on SIPs site yet, but it seems there is a new sito+ exhaust for the 4T 150cc lml star/ genuine stella out now. i don't know any thing about it yet, but i like that it has that stock look to it. any performance gains and a bit of a grumble/growl would be a bonus.