Jump to content
Sign in to follow this  

Rmx Jetting ??

Recommended Posts

97 RMX250, PC full exhaust,airbox top cut open. 500-1000 ft elevation

current jetting

main 165

pilot 55

needle stock R1472 M1L clip position 2

I am going to install rm head gskt

only 1 short ride on bike but apeared lean at idle

midrange wasnt to bad wot apeared ok but some hesitation and sputtering when wacking throttle open in all areas.

I put this here Eddie I know there is a few RMX's on this board and they might find your suggestions helpfull..

Share this post


Link to post
Share on other sites

Well, since no answers yet, I'll give her a shot.

both the 1472 and 165 sound a slight bit on the lean side which would go along with some hesitation/sputtering ( depending on what you mean by sputtering..... is it 4-cycling or a popping sputter?). I'd try a 1469 needle ( same taper/length, but smaller diameter needle....making it a bit richer) and I'd also try a main more in the 172-175 range.

Share this post


Link to post
Share on other sites
how far is the choke knob screwed out?

Eddie I got a chance to mess with bike a little this afternoon.

I am sure I have a partialy blocked idle circut,I tried a 50,55,and 60 pilot jet,when playing with air screw and idle adjust on choke all jets came out within 1/4 turn on air and choke screws.9 turns open on choke 1 1/2 tuns on air just to keep it running at idle,I'm sure its just running 90% off starting circut to idle at all,funny thing is 50 pilot had the smoothest idle,but both adjustments still wanted to be in same place as 55 and 60 to idle at all.

Carb looks realy clean and I did blow some carb cleaner and air through all passages,guess I'll clean again next time I get a chance to mess with it.

I have a feeling this has been a ongoing problem with bike for awhile,the guy I bought it from told me he had the carb worked on,and wasnt happy with it,he told the shop that it was hard starting and fouled plugs,the most exelant mechanic told him thats just how RMX's are :applause:

Also set float level to specs it was set way high:excuseme:

Share this post


Link to post
Share on other sites

you dont want the choke open that far for sure.

i personally set that style carb for no idle to avoid any issues.

Share this post


Link to post
Share on other sites

i personally set that style carb for no idle to avoid any issues.

do you set for no idle at all?I dont care about having a great idle but i dont want it dying like you hit the kill switch,when you let off the gas.

is that why people change to the PWK?

Share this post


Link to post
Share on other sites

thats one of the reasons,but i set all my 2 strokes for no idle.i dont like them towing me thru the corner when the throttle is off (blang blang blang blang).

i would set ti so it idle just a for few seconds.

Share this post


Link to post
Share on other sites

Eddie,CharlieT Thanks.

I went with a 170 main largest I had,it realy helped,nice midrange through WOT (I think it could still be a little crisper but does sound and respond pretty well)

The closed throttle to 1/4 throttle still sucks big time though,tried 3 pilots 50,55,60 no real differance,passages and jets realy apear to be clean,since I have to open choke screw so far (9 turns) do I need to go ritcher on pilot?

65?70? that sounds awfully large to me?

I checked reeds they are a fiber aftermarket they look good.

I realy dont think its crank seals but I suppose it could be.

Any Other ideas or suggestions.

I plan on getting a 172 and 175 main tuesday.I guess I'll get a couple more pilots also 65,70?

Also I'll see if I can come up with a 1469 needle..

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×