Various help

[luc1992]

Hey guys, this post might be a little long so bear with me.
I installed a Tecnigas type R exhaust today and here is what happened. After the installation i went out for a test drive and noticed that it had a very spotty power band. It would basically be slow off the line, i could feel acceleration from 10 to 20mph and than slow to 30ish and it would barely top 35 (i was going 40 mph before the swap) I also noticed that after idling for 30 secs or more it would be peppy of the line but it would slowly lose power as i rode around, when i let it idle for a while again it would perform well for a few seconds and gradually lose power. I tinkered with the carb and then air box trying various settings and found that increasing the airflow (tried running without the airbox cover for a few seconds) did not help. Played around with the main mixture needle and found that it would not make a huge difference in performance weather i screwed it in or out.
Now i did not change the jet and i suppose it does need to be changed but i did not think i would lose power if i did not change it, i thought it would stay the same and i would get a slightly better acceleration. Also the pipe came with some roller weights, i did not install them because i did not have my tool to lock the crankshaft on hand. I will try to install the roller weights latter next week and see what happens.
And finally last question, there was a rubber tube that ran to a small plastic box type thing that connected to the stock exhaust, however there is no port for this thing on the new exhaust, does anyone know what it is?
thanks for the help, it is greatly appreciated, i cant wait to make the most out of this pipe.

[sidthesloth]

With changing your pipe you will be running lean, what colour is your plug now? If it was a vacuum hose and you have not plugged it, that will make it run even more lean, this is not a good situation for your engine. Now the good news, when you rejet to suit the exhaust and get a high flow air filter, you will have a big grin on your face. The rollers they supply with the exhaust are to put the engine into the optimum rev range to utilise the power increase of the pipe.

[luc1992]

haha very good new indeed, so i will try and not use it too much so i dont damage the engine and next week i will get a jet and an air filter and put the new rollers in. Thanks!

[art]

  Definatly do your plug chops! with mine you needed to run the 7.5g rollers for best performance. This was with an open airbox and a #95 main jet. The hose was a rebreather sort of thing  Cap it it is un needed now. Did you get it de restricted. (cdi and drive boss) if so 50= is real easy Good luck

[luc1992]

I did get it derestricted, did it myself. Changed the drive boss and cut the bottom of the cdi, although wierdly i do not think my cdi was restricted in the first place (which it should be for an 09' model) because it did not make a difference when i cut it, i went 40mph before (after i changed the drive boss) and same speed after the cdi mod. I will get a 95 main jet, i just need to figure out what kind of jet it is. I remember one of you guys saying they thought it was a keihin jet.

[art]

http://www.pjmotorsports.com/keihin-jets.html#main jets I think it's the 99101-116 . I have not ordered from them.  The 2009 and newer cdi has to be replaced. The cut didn't work on mine. Look for a kymco cobra cdi that is the one that is derestricted,there may be others but I have not tried any yet. See if that helps

[luc1992]

is there a way to know if the cut worked or not? can i get to 40 mph with a restricted cdi?

[juice]

Ebay tiapai scooter assassins has unrestricted cdi's for sale . Good luck .

[art]

40 mph is about max with the cdi restricted. You need to be running down hill to get past that. Once past that speed you will feel the spark being cut to the plug by the restriction. It will not rev any higher. You should be able to hit 50+ de restricted and upjetted.

[luc1992]

So small update on the upgrades, i installed a #92 main jet, however it seems to be running to rich now, the performance has not improved over the #70 stock jet (i discovered it was a #70 main stock jet in my scoot, probably another sort of restriction) i guess going from a 70 to a 92 is too much of a big leap even with the new pipe. I tried increasing airflow by taking the cover off the airbox and affixing my filter with ties so it would not fall out, it helps a little but but still not enough.
Another thing is that adjusting the carb is weird now, i can screw the main mixture screw all the way in and the engine will not shut off it just revs higher.
so basically up jetting did not change, except now i am running very rich as opposed to very lean so it's safer i guess, i still do not have a performance increase which is the reason i changed the pipe in the first place.
do you guys think it is the jet that is too big? or is there something else that i am missing.
P.S i still did not put the rollers that came with the pipe in the variation i want to get the jetting right before i do that.

thanks.   

[art]

 You will need to go to 7.5g roller. The new cdi and open air filter for best results. The #95 main was suggested for open airbox an #85 if not open should work.
 Your air gas screw is just for idle mix turn out about 1 1/2 turns then set idle screw. Give that a try  Good luck

[luc1992]

ahhh, i see, i thought it was a full on mixture screw, i will try that thanks, i will also install the rollers supplied with the pipe.
i will repost here with results, i guess making holes in the original airbox counts as on open airbox?

[luc1992]

WOW, i replaced the rollers and what a difference, the acceleration is way better and the top speed has increased to an indicated 46-47, i have not hit the elusive 50mph though. I atribute that to several factors, i have not changed my gearcase oil and it is due for a change, also my belt is 4000km old. I did not change the cdi but i dont think it is restricted if i can go faster than 40. I am also running the stock airbox without the cover (holding the filter there with some strings criss crossed across the airfilter element) however do you think that a K&N filter would help me get to that magic 50 mark? it looks like the actual rubber tube that connects the airbox to the carb is a bit smaller than the carb opening itself so that could restrict airflow somewhat.

[Peters]

Yeah you need those lighter rollers dude. I put mine in before I put the pipe on just to see what they did . A matter of fact I still need to go a little lighter with my fat butt. My 09 cdi is not restricted (anymore at least) I unpluged the green wire like a week after I got it and didn't notice any difference. Of course I could barely get to 30mph then(boss drive). Now I have got it to 52-53(downhill) indicated and its never cut out.

Im not positive but I don't think you need to replace the belt yet.

Even though you have it running good you need to fine tune the mix at idle, mid throttle, and WOT. Plug chops! Your at the same point as me. I still havent got it perfect yet.

You ordered your main jet from art's website part#99101-116?

[wordslinger]

...belt and g-box oil should be fine...

WOW, i replaced the rollers and what a difference, the acceleration is way better and the top speed has increased to an indicated 46-47,

..what's your roller weights now?