RD250 with 350 top end jetting

[RD350NL]

Hi all

I am in the process of converting my rd250b to a 350. For the jetting I referred to the manual, which indicates I should use 25 pilot and 130 main. Currently I am running 27.5 pilot and 120 main, the 250 top end runs great with this jetting. The concern I am having is that virtually everywhere I read the main should be 140 when running 350.

Can someone confirm the manual has a typo? Or should 25 pilot and 130 be fine.

PS: Bike is bone stock (does have a Vape ignition)

Thanks already

[sav0r (CL MotoTech)]

Just go rich and see. It can't hurt.

[m in sc]

that jetting also applies to a stock airbox, stock 350 carbs. us market rd350s were indeed 140 73& 74. so, the jet tubes have to be the same as a 350 and all sirbox parts in place w a stock filter, etc. otherwise,  the jetting will need to be figured out. 250/350 airboxes etc are the same as are the carbs,  but I'm pretty sure the jet tube and needle for both are 0-8 and 514 in the middle clip

[stresa]

@RD350NL
I have a couple of carb charts, parts lists and manuals, both USA and Europe versions, but not in one is a #130 stated for a 350. For a 73/74 350 always the numbers Mark stated or a #105 main jet, 5L3 needle, 2.0 carb slide with a baffled airfilter for the 1975 Europe B model which was a slightly different model to the USA B ones.
But carb fine tuning always depends on your own engine.
As @sav0r wrote. Start rich and work down if needed.
Regards Uwe