Grand vista 250 carb setup

[calvinsmit]

Can someone help me with the piston/slide needle length on a 250 grand dink(vista). I really need to know how far is sticks out measured from the bottom of the slide to the end of the needle.Someone had previously messed with the carb.It could even have a incorrect needle in if I compare to the manual. In fact the plastic needle holder was. I have a way in which I have secured the needle and so the bike is now performing well but I want to get the length and taper correct.

[zombie]

The needle will all depend on which carb you have. Does your needle have slots cut in it for adjustment? There is an "e" clip on most that will adjust the height. MOST factory settings are in the CENTER slot, giving you 2 up, and 2 down adjustments. You can go to a Home Depot type store to buy an "e" clip to fit your needle. The BEST way t tell if yours is correct is the performance of your scoot. Plug readings will tell all. here is a link to the best chart I have seen. http://www.dansmc.com/spark_plugs/spark_plugs_catalog.html      Just take a look at your plug because measurements are not consistent for tuning, only a basic guide line. Post back!

[calvinsmit]

Mine does not have slots for a circlip.I use unleaded fuel for here ,so pug readings are not as I was used to in the 'old days'. (the exhaust and plugs are just dark.not quite soetie)The bike midrange power is good But It was a bit stronger when I fastened the needle slightly higher.That then gave me 18.5 k's per liter. I am expecting 28-30 k's per liter. I guess I will just see what my fuel consumption is like.It would of been great to get a approximate need length for my carb

[zombie]

You will still need to post the make, and model of your carb. to have someone with a kind heart, and the same carb to measure theirs for you. If it ran better with the needle raised, you may be running a little lean. Raising the needle will richen the mixture. A dark plug is saying the opposite though. The only SURE way to know 100% would be to order the correct needle for your carb. Not just for that bike but for that carb. Also the Kymco manuals are FAMOUS for mis-information so don't lose too much sleep over that comparison.