A forum for owners of Yamaha TTR250 trail and enduro bikes!

Tone · Member

Keihin main jet part number

texasT · Senior Member

http://www.jetsrus.com/a_jets_by_carburetor_type/a_jet_kits_keihin_selection.htm

...can't say for sure, but you might poke around here

texasT · Senior Member

If you do a SEARCH in here (TTR) you may find a thread that helps.
Here is one that is about (mostly) OE jetting.
http://ttr250.activeboard.com/t49703293/main-nozzle-differences/

-- Edited by Cubber on Wednesday 3rd of July 2013 02:06:50 PM

Tone · Member

Thanks Tex, I haven't stripped my carb down yet - so don't have the measurements. I was hoping someone who has done the job would know, as there seems to be rather a lot of choice. I think in the end I might have to take my old jet into a dealer.

TTRfan · Super Guru

Hi Tone and welcome to the forum!

OOI, why do you think a new main jet is needed?

Brian

Tone · Member

Hi chaps, thanks for the info.

I have had my bike for a couple of years and have only just got round to getting it back on the road/lanes after storage. I ran the carb and tank dry beforehand but despite a dealer service I know that it was not running properly i.e. only running with the choke on and then not running smoothly. It started up ok and would rev to about quarter throttle and would then die off.

Having read all the info on here and the FAQ.s. I have resolved to do a minor strip and carb clean as well as change all the fluids and lube and thought I might as well replace the jets and diaphraghm.

I have sourced a pilot jet and gaskets from J R Sutton but cannot find a Yamaha spares supplier for the diaphraghm or main jet.
My bike is a 2003 Blue model with 10660miles on the clock. To date it has not been off-road to my knowledge.

Tone

BMW R100T
1150GSA

texasT · Senior Member

Tone,
WELCOME Sir, (I think I forgot my manners)
I have a 2004, US model blue tank, and the pretty sure the (OE) stock jet is not 150 (or a keihin for that matter). confuse

BUT- If you know you have 150's in there now, you are doing the right thing by replacing what is in there now, if it was running ok before.
But if you switch from the stock jet and install the 150, it may be too big, depending on several factors. PIPE makes a difference as does elevation, etc...
Might add to your signature with what you are running that may differ from OE parts. With a little background data, you may be able to find a post with similar set-up and copy settings.

http://www.bikebandit.com/

might see if these guys ship to the old world? I buy from them with good luck

OR BRIAN AND MRS TTR MAY HAVE WHAT YOU NEED!!---?

...
cubber, I see where you edited my post. Hope I had no nasty words in there/ what did i do / I do have trouble pasting links...

Cubber · Super Guru

I merely livened up your link - makes it easier for others to click instead of cutting & pasting (not pastying wink )

Martyn