Jetting ?

[armpump]

Someone point me to the jetting section?

need to get some basic ideas of what to run.

Beta rev3 270 and Rev 80

Altitude:1800 meters above sea level

Temp: 15-30 degrees c

[armpump]

Anybody???

[dan williams]

We're just scared of your avatar. What year bikes? Any exhaust or airbox modifications? Mikuni or Keihin. You see it's not a cookbook question. There is no "correct jet" There's only the correct jets for your bike, altitude, air density, temperature, riding style. That's one reason people are a little leery of wading in with a set of numbers. Carb tuning information is readily available on the web. Google for the Mikuni tuning guide I think from SUDCO. That should give a rough estimate of how many jet sizes you'll need to go down for altitude but you really need to spend the time to do the testing with the bike and a set of jets if you want it done properly. I usually carry a couple of sizes plus and minus of both pilot and mains when tuning. Yes it's a pain but it's so worth it.

Having said that usually around here people go down one size on the pilot to a 27.5 and one size on the main to a 130 for the 270 with a Mikuni but we're at sea level.

[armpump]

Thank you for the reply.

Beta rev 270 2002/03 Stock(fresh packing) new rings.

Beta rev 80 07 Stock (1 ride old)

Just want to get a basis to work from as i suspect it will have coastal jets fitted and we are fairly high at around 5000ft.

Ie recomended needle, main and pilot so that i can then get them and a few around them and start the process.

Anybody have success in dyno tuning a trials bike ?