[P99]

Ok, have read all of the posts and other sources on jetting, so many options. So thought I would just put this out there to see if I am on the right track before I install everything.

2005 CRF250X, Canadian Model

About to do the below:
Cut the Air Box
Install a Boysen AP Cover
Install a FMF Q4
Install a Scary Fast Power Now
Install a Rekluse Clutch
Install a Twin Air Filter, stock screen
Install a Long Fuel Screw
Change the jetting

The FMF came with a Dynojet FMF jet kit, one needle and a bunch of jets, biggest one is 155. Had asked for JD Kit but this came instead. So I bought a 42 Pilot and a 164 Main as it appears these are the most recommended.

Plan to put the needle at the 4th position, install the 42 Pilot and the 164 Main. Will this work the best for riding at 0 - 1500 Ft on the rainy westcoast. Or is there a better set up for this bike with these mods.

Thanks in advance for your reply.

P99

[mdmasher]

Do all but two of your list.
Drop the scary fast and the boysen cover.
If you bike doesn't jump from the low end or the bike takes a second to get going when you twist the throttle,
change the leak jet. I don't know much about the 250.
But the leak jet made my 450 jump RFN (right fricking now) when I kick it.
The stock leak jet in the 450 was a #70 and the dealer said the #50 was the ticket. the #50 was a much larger hole then the #70. Jets are weird, just like letter drill bits and number (#) as well as metric and standard. Keep reading some of the older postings.

Hope this helps.

[P99]

Good Day MDMasher

Many thanks for your advice, much appreciated.

Gather from your message that changing the leak jet to a 50 is the better fix than installing the Power Now and the Boysen. Thank you for this advice.

Brgds, P99

[mdmasher]

The boysen only holds twice the amount of fuel in the tank per say. It will not deliver the fuel.
The leak jet was the ticket for my set up.
The set up for the 250 is different the the 450.
Look at some of the older postings.

The power now threads on this site and what I am hearing from a pipe manufacture states no real gain over the full range of RPM's. Plus 3% hear, less 3% there. $200 + or - for what?

I think the bike has enough power once the carb, intake and pipe mods are completed and to spend the balance of any money you would like to spend on protection and suspension tuning for your investment and yourself.


When in doubt- Gas it

[Motomike41]

I agree with Masher on the power now a waste of money! If all your changes don't work for you change the gearing.

[P99]

Hi Guys, thanks for your advice.

Well, installed everything including the Power Now and the AP Cover. With not great results.

When I took the old jets out, found that the main was a 170 and the pilot a 40, (the bike had an R muffler on it, so maybe thats why it was jetted with this main), replaced the main with 162, the pilot with a 42 and put in the Dynojet needle with the clip at the 4th position. Installed the Power Now and the Cover, the fMF Q4 and the Rekluse.

Results. Idles Ok, not great but Ok, Low end great no Bog, get over say 3000 RPM and it sounds and feels like I am hitting a rev limiter. This happens when riding it and also on the stand. As I slowly twist the throttle it gets to point where it won't rev smoothly, stutters, and revs go up and down on thier own. Rekluse seems to working, could not really test it due to above.

So, have put the 170 back in, no change. Have just now swapped the needle out and pulled out the power now. Will leave the pilot and the AP cover alone.

If you have any suggestions on what else I should check before I button it up and test it please let me know.

Any suggestions much appreciated.

Before all of the changes bike ran strong, a bit of a bog at the bottom and was a bit loud, hence the change to the Q4 and all of the other changes.

Thanks again for your help.

P99

[Halen]

Hey bud...
I have the same bike as you (and ride the same places)
The JD jetting kit is a designed system that when installed works very well 'together'. I will admit not knowing too much of the FMF jets (I am running a FMF Powercore Ti) but am extremely happy with the JD kit and how my bike runs. Check out my garage and consider getting the JD kit... I know you've probably spent a few bucks already but going with the JD system is a proven must.
cheers!!!
Van.

[P99]

Hey Halen,

Thanks for your message, I ordered the JD kit when I ordered the pipe from a shop in Oregon, what they sent was the FMF Dynojet Kit, so have to order JD kit.

Anyways went back to the 170 Main that was already in the bike and the needle at the 3rd position and it runs pretty good. Left out the Power Now. Will put in the JD Kit when I get it and see how it compares.

The Rekluse works great, installation was straight forward. I didn't order the perch adjuster, since I wanted to run the rear brake on the left side. If you don't order the perch adjuster the spring adjuster that comes with the kit is not very good, very basic, not up to the quality of the other parts, will be easy to make something better. The Reklue clutch works great, rode some technical trails at Cat Lake today and all worked fine, the bike stayed rubber side down much more than in the past. For a beginner like me the Rekluse is a great help.

Thanks for everyones advice regarding the jetting, now just have to get the suspension dialed in.

P99

[P99]

Furhter to my last post,
Have installed the JD Kit,
Red Needle 5th Position as per instructions
Power Now
42 Pilot
165 Main
FMF Q4
Boysen Quick Shot
Removed the Back fire screen, cut airbox
Fuel Screw 2 turns out.
O-ring (thick) mod

Bike runs pretty good. No bog, pretty even power through out, comes on hard the last 3/4, but still pretty strong from the bottom. Believe that it could be better in the bottom end. Quite hard to start when cold. Now have to give it just abit of throttle to get is started when hot.

Plan to take out the Power Now becuase I really can't tell if it is actually doing anything so might as well get rid of it and see if I can see a difference.

Wondering if I should change the needle to the 4th position or go up in main jet. Would like to get rid of the hard starting when cold and having to give it a bit of throttle when hot to get it going, or should I just adjust the fuel screw, in our out?

Any suggestions much apprecieated.

Brgds, P99