|
|
Post by gotbaja on Aug 22, 2012 17:48:52 GMT -5
Yes, i know, this is the most overplayed question on the face of the scooter-forum planet, but hey why not right? lol. So here are the planned mods:
Uni Filter.
Ebay High Flow exhaust. (from what i can tell, these are just pipes with resonated cans on the end, so im assuming not much back pressure) such as this:http://www.ebay.com/itm/NEW-2012-STAINLESS-STEEL-scooter-exhaust-shorty-performance-50cc-150cc-kart-gy6-/130752235973?pt=Other_Vehicle_Parts&hash=item1e7170c9c5&vxp=mtr
NCY Variator with stock rollers (already ordered from envirmoto)
Other Specs that are important
Elevation: 5312ft-5212ft (i travel to and from a local suburb of Albuquerque for work)
My weight: 240lbs, 5'11"
so what would be the ideal jet size? i kinda just want to get a new carb too... tips?
|
|
|
|
Post by skuttadawg on Aug 22, 2012 21:50:58 GMT -5
I would simply get a jet kit to have lots of sizes to test
|
|
|
|
Post by gotbaja on Aug 22, 2012 22:59:56 GMT -5
id rather not take the carb on and off 10 times. i work 35 hours a week and school mon/tues/wed/fri lol. has anyone had expirience with the proposed setup?
|
|
|
|
Post by skuttadawg on Aug 22, 2012 23:28:51 GMT -5
|
|
|
|
Post by 90GTVert on Aug 23, 2012 9:09:27 GMT -5
You're prob looking at 3-5% decrease in jet size at that elevation vs sea level. I'm guessing 85-90 main jet. Just a guess, and it's been a while since I've worked on a 4 stroke. Whatever you use is nothing more than a guess if you aren't willing to spend a little time to tune it. Guess wrong on the low side and you'll get to spend some time and money replacing parts.
|
|
|
|
Post by gotbaja on Aug 23, 2012 12:28:27 GMT -5
Well i was thinking of getting an 88 main jet, as ive heard these work good with small mods. I suppose i could just wait till i have some free time and just buy a jet tuning kit. EFI would be awesome lol but a little over budget :scoot2:
|
|
|
|
Post by gotbaja on Aug 23, 2012 12:33:40 GMT -5
so, having said that, what size of carb would you recomend? 18mm? 20mm?
|
|
|
|
Post by skuttadawg on Aug 23, 2012 13:26:27 GMT -5
18 a 20 would have more flow and be leaner than the 18
|
|
noday
Scoot Enthusiast
Posts: 149
|
Post by noday on Aug 23, 2012 20:14:24 GMT -5
there is no 1 jet size answer to your question
at 5,000 ft, the air and O2 is less dense, about 83% of sea level. most guys say down jet 2 steps for that altitude
but to do that you need to know the optimal jet size for the same setup at sea level.
given that you want to make various different changes to increase engine power, I am guessing somewhere in the low 80s or high 70s.
even so, you will still be under powered by that 83% O2
to get more power, you need more CCs
if you upgrade to a 47mm bigbore kit, you will be closer to your goal.
I do not see any way around multiple jet sizes, and repeat trials, unless unless you can find someone local with the exact same setup to give more guidance.
any and everything you change that affects engine air flow, also effects the best jet size
|
|
|
|
Post by usmcdoc on Aug 23, 2012 20:25:11 GMT -5
What jet is in it now?....they usually come pretty lean already. Is the engine stock...or big bore?
|
|
|
|
Post by gotbaja on Aug 23, 2012 22:23:30 GMT -5
i was thinking about a bbk... right now it is completely stock 100%. i know they jet these really lean to pass emissions. hmm.....
|
|
