Long term KLX250S review

[bhorocks]

Originally Posted by Rob.G

I emailed Bill Blue last week with some questions and haven't heard back either. It usually takes him a couple of days to reply, but this time it's been a while. The address I have for him is b_jblue (at) sbcglobal.net. Maybe he's been out of town.

I was asking him about stock on the 351 kit, and also what his opinion was on aftermarket cams with the kit. Webcams has a couple of nice looking cams that I wonder if they wouldn't do well with it. I remember hearing that the 351 doesn't really rev above 9000 RPM, and I'm guessing that's due to the valve size and/or cam lift. A higher-lift cam might help that a bit.

Rob

I got an email back. They will be back after fathers day. Building a cabin.

Sent from my SCH-I500 using Tapatalk 2

[griffo1962]

Originally Posted by bhorocks

I got an email back. They will be back after fathers day. Building a cabin.

Fathers Day down under is September..... when is it up there??

[Landon]

Originally Posted by griffo1962

Fathers Day down under is September..... when is it up there??

June 17th this year

[Rob.G]

I'm also having jetting issues. This is with the Bill Blue TM33 pumper carb.

Current settings: 37.5 pilot, needle in middle, 135 main, AF screw 2 turns out
Mods: Snorkel Removed, TwinAir filter, KLX300 exhaust w/o end cap, brand new spark plug (NGK CR8E, stock plug)

Anything from 3/4 throttle on up (except WOT), and it "cuts out" pretty bad... RPM doesn't matter, just happens on throttle position. Going WOT solves issue, but that's not always practical.

Today I did some testing. I put the snorkel back in. Now the thing barely runs above half throttle, including WOT.

Came back, removed air box lid entirely. Runs MUCH better... best it has so far, except there's still a stumble/miss at 7500 RPM in every gear.

I would prefer to have it running properly with either the air box lid/snorkel or the air box lid w/o snorkel, and get rid of that miss at 7500.

What do you think? Drop the pilot to a 35 and drop the needle a notch?

I'm at 4500' elevation if that matters, though I would like to have it set to run fine at sea level and have it a little fat up here and up to 6-8k as long as it doesn't run like crap. I could then pull the air box lid if I had to at higher elevations.

Rob

[BeenThere]

Originally Posted by Rob.G

I'm also having jetting issues. This is with the Bill Blue TM33 pumper carb.

Rob

This is what worries me about going to the 351 kit. Some say just go with the jets Bill tells you to use and everything will work great. Then there are others like Rob here that can't seem to get it right. I've been watching most all the 351 threads here and on the KLX forum and so far it seems to be a mixed bag of success vs. problems.

Norm

[Rob.G]

Originally Posted by BeenThere

This is what worries me about going to the 351 kit. Some say just go with the jets Bill tells you to use and everything will work great. Then there are others like Rob here that can't seem to get it right. I've been watching most all the 351 threads here and on the KLX forum and so far it seems to be a mixed bag of success vs. problems.

Norm

I plan to do the 351 kit, hopefully in the next month or so. I still have the stock carb and if I can't get things right with this one, I'll stick that one back on and go from there.

If I already had the 35 pilot, I would go ahead and pull the carb and make the changes... but I don't, and it's windy and getting colder today with rain coming tonight and tomorrow, so no point in trying again before Wednesday.

I can't help but wonder if the cutting out at 7500 might be my CDI or regulator. If it was at a particular throttle position, I might think it was going fat right then, but since it's at exactly 7500 in every gear, it kinda seems ignition-related.

Rob

[IDRIDR]

Rob, Have you done that grounding thing that a bunch of 09+ owners have completed?

[Rob.G]

Originally Posted by IDRIDR

Rob, Have you done that grounding thing that a bunch of 09+ owners have completed?

No; this is the first I've heard of it. Tell me more please! :)

Rob

[DurtDevil]

Originally Posted by BeenThere

This is what worries me about going to the 351 kit. Some say just go with the jets Bill tells you to use and everything will work great. Then there are others like Rob here that can't seem to get it right. I've been watching most all the 351 threads here and on the KLX forum and so far it seems to be a mixed bag of success vs. problems.

Norm

I ride a '07 KLX, bought it second hand with 110 miles on it. At 5500 (after Two Bros slip on muffler, KX300 (?) snorkel, Stage II jet kit and UNI air filter) put on 351 kit and the Mikuni 34 pumper carb (which came jetted specifically to my altitude and for air box and muffler mods by Bill right out of box), and the motor sings. Granted I had a friend/mechanic install but even he was surprised... Said he didn't adjust anything, that never happens, plug and play install. Had it installed four weeks ago, put 250 break in miles on it (plenty of trail, even a turkey run event) then rode it with a 13t from NE MA out to SW VT (ie, lots of long high rpm miles) and rode with pure dirt bikes (KTMs, Husas, and CRFs) for two days up and down the mountain ridges. The motor on this bike is now incredibly strong, incredibly fun, pulls HARD down low and I had absolutely no problem hanging with the other bikes and ended the weekend riding mid - front pack... Just because the motor is so perfect now. Could largely leave in 2nd gear and almost from a stop up to about 30 it was right in the meat of the torque. Long story yes, but I was as hesitant as anyone about mucking up what was already a fun and capable bike... After a 1000 fast miles on the new motor I could not be happier.... Out of the box Bill Blue's set up was rock solid. Liner notes: I now switch 13t, 4t, and even 15t b/c there is enough motor to do it, and the bike is so versatile. Second note - the suspension is the only thing left to fix on this bike.... Coming down the mountain passes and riding into the water run off culverts completely crushed the suspension and made me worried I'd pop a tube when the forks maxed out.

If you're already considering the 351, do it and don't look back - I for one am not only really pleased, I'm really surprised at how well it works with the bike.

[SamM]

Call Rick at Cogent Dynamics when you are ready to change the suspension. He rebuilt my KLX250SF shock when I converted it into a dualsport. Best thing that I have done so far. The Cogent shock works great. Just added the IMS tank and the 351cc engine kit is next on my list.

[250senuf]

Originally Posted by Rob.G

No; this is the first I've heard of it. Tell me more please! :)

Rob

Here:
http://www.kawasakiforums.com/forum/...e7/#post452954

[Bultaco206]

Originally Posted by BeenThere

This is what worries me about going to the 351 kit. Some say just go with the jets Bill tells you to use and everything will work great. Then there are others like Rob here that can't seem to get it right. I've been watching most all the 351 threads here and on the KLX forum and so far it seems to be a mixed bag of success vs. problems.

Norm

When I added my 351 kit I knew I was keeping the stock carb. And Bill's recommendations were spot-on...with a Powerbomb header and Powercore silencer...later swapped for a Q4. The bike is crisp and pulls hard with no popping on decel and no bluing of the header...based on Bill's advice. No mixed bag here. Jump in...you won't regret it.

Now, for that ridiculous suspension...

[Rob.G]

More testing...

Being bored, I went out and dropped the needle one notch. It's now in the 2nd position from the top. I removed the snorkel again and replaced the air box lid, then went for a ride.

It runs waaaay better than it has so far. Wow, very nice... it actually has torque!! That is, up until around 9000 RPM and 7/8th's throttle... that's when the "cutting out" starts again. It's not quite as bad as before.

So now I'm thinking... what if this is how it would be if jetted for sea level? Maybe I should put the needle back in the third (middle) position and just run w/o the air box lid up here, and replace the lid when I'm at sea level?

Rob

[TNC]

Originally Posted by Rob.G

More testing...

Being bored, I went out and dropped the needle one notch. It's now in the 2nd position from the top. I removed the snorkel again and replaced the air box lid, then went for a ride.

It runs waaaay better than it has so far. Wow, very nice... it actually has torque!! That is, up until around 9000 RPM and 7/8th's throttle... that's when the "cutting out" starts again. It's not quite as bad as before.

So now I'm thinking... what if this is how it would be if jetted for sea level? Maybe I should put the needle back in the third (middle) position and just run w/o the air box lid up here, and replace the lid when I'm at sea level?

Rob

9000 rpm and 7/8ths throttle?...main jet, isn't it?

[Rob.G]

Originally Posted by TNC

9000 rpm and 7/8ths throttle?...main jet, isn't it?

Might be.

I made more changes today but it's been cold so I haven't ridden it to test. I dropped the main jet one notch to a 132.5, and dropped the pilot to a 35. I'm eager to go for a test ride tomorrow to see what the difference is.

Rob