Almost Done Tuning The 250, Need A Little More Help

[PYF]

Hi everybody...Since I bought my 250 3 months ago, I had a lot of fun but have never been able to be spot on on jetting.

Since I bought it, I rebored it .040 over, installed new pistons and rings, ported the cylinder and shaved the head. I also run open air box and a FMF pipe. Funny thing, I just discovered yesterday I had a PWK (Never made the link that the stock one was a PJ)...Don't know what size though, will measure it shortly...


The main problem was probably the mid range. Let's say I'm rolling slowly and pin it WOT in a higher gear, It would absolutly bogs and sputters until it hits mid-rpm...I just lowered the needle and It cleared the problem wonderful. But I'm still having some small problem pissing me off...

It cuts a little on top end in the first 3 gears if I pin it WOT. If I rolls in high gear in 1/4-3/4 throttle, I hear a sound that looks like little bubbles popping. Am I still too rich on the needle ?

The plug is a nice brown chocolate, but it stills cuts a little on top as I said. By the way, when you pin your 250 WOT on neutral, does your rev to the moon? Mine kinda hit a rev limiter (Does the 250 have a rev limiter ? I don't think so...)

So right now my setup is like that:

155 Main Jet
2th position needle
50 Pilot Jet
2.5 Turn On Air Screw

1200 feet over sea level altitude
Today the temperature was 64 and cloudy

I know it's a little harder to help me since I don't know what size carb I have but I SUppose it's a 36 or 38 :S


Anyways thanks a lot in advance for your help fellow 250r riders,

Pierre-Yves

[crazedape]

Sounds like an air leak. Mine did that and then I blew a hole in the piston running wide open. Sometimes the head gaskets don't seal right.

[PYF]

Originally posted by crazedape
Sounds like an air leak. Mine did that and then I blew a hole in the piston running wide open. Sometimes the head gaskets don't seal right.

So a leak down test would be a good idea?

EDIT: I have a question though...If I had an air leak, wouldn't my plug be extremely white with the jetting I'm running. On top of that, the bike doesn't have rev variation on anything strange...

[PYF]

Hmmm, I just found out that my carb would be a 33mm PWK...Would it be too small and cause me some trouble ?

[TheFontMaster]

the stock carb is 34 mm. I've heard of people running smaller carbs to get more low end power. I would try going down on the main to a 150. It sounds rich. And go down another step on the needle. And yes the 250r's do have a rev limiter.

[PYF]

Originally posted by TheFontMaster
the stock carb is 34 mm. I've heard of people running smaller carbs to get more low end power. I would try going down on the main to a 150. It sounds rich. And go down another step on the needle. And yes the 250r's do have a rev limiter.

Thanks, I'm gonna get a 38 PWK A/S Soon though. As for my popping sound, probably because my head pipe is leaking a little. What could cause the head pipe to leak and how can I fix it ASAP...

And going another clip size on the needle...never heard of anyone running 1st position on a needle...though I never heard of anybody running a 33 mm on a R lol...

[250r4life]

33mm carb... i have never heard of such a thing... who in the world makes a 33 carb? ive heard of people putting 34s on blasters and banshees, but...

[TheFontMaster]

Originally posted by PYF
Thanks, I'm gonna get a 38 PWK A/S Soon though. As for my popping sound, probably because my head pipe is leaking a little. What could cause the head pipe to leak and how can I fix it ASAP...

You need some high temp cylicone to put around all the seals in your exaust. That will seal it up good and you won't have the leaking problem anymore.

[zedicus00]

ive got a good 38 a/s fo sale if you need it. 33 pwk should run o.k. but it is too small to get much power out of an R with. blasters come with like a 24mm carb stock, even a 28pwk is an upgrade for a blaster.

[PYF]

Originally posted by zedicus00
ive got a good 38 a/s fo sale if you need it. 33 pwk should run o.k. but it is too small to get much power out of an R with. blasters come with like a 24mm carb stock, even a 28pwk is an upgrade for a blaster.

How much for it ?

I just understood I'm not really taking advantage of my ported cylinder.....Kinda piss me off

By the way, stupid question but, would I see a really big change with the 38 A/S over the 33 since I'm ported/milled and thing like that. I'm not really built, but I'm not stock

250r4life: The 33 mm is a Keihin PWK

http://www.sudco.com/pwk.html

[zedicus00]

you should see a huge difference in all around power going to a 38 A/S even with mild porting. these carbs keep good low end power and are big enouf to provide good high end flow.

120 shipped if yur in the lower 48. comes with needle and jets.

note: looks like yur in canada, 110$ plus exact cost of shipping to you. and you pay 3% paypal fee.

[PYF]

Does it comes with the cable...if so I would seriously consider buying it..

Pierre-Yves

[zedicus00]

the cable from yur 33 pwk will work fine. i dont have any extra cables at the moment.

[PYF]

Originally posted by zedicus00
the cable from yur 33 pwk will work fine. i dont have any extra cables at the moment.

IS the carb in good condition ? Got any pics ? Why did people said I need another cable for the 38? Can you Quote me how much it would cost with USPS (I'm gonna PM you my adress right now)

Thanks a lot

[zedicus00]

yes, yes, they assumed you had a stock carb on yur quad, in which case you would have needed a new cable. all pwk carbs take the same cable. an A/S carb is just an extension of the PWK series.