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Need to smooth out the power on a 17 250 RE

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My buddy, a long time KTM 250 xcw rider, got a 17 250 RE this year and he's struggling with the power delivery.  This is in very rugged, technical, rocky terrain.  The jetting is stock, I think 165 main, needle dropped one clip, and runs very well.  He has 13/50 gearing and runs the Gnarly pipe.  He's a very good rider and rides at a minimum 3x per week, I think he has 120 hours on his Beta since May. 

This weekend at our clubs Trail Fest big ride weekend he noticed the wheel bearings on his Beta getting loose so he ran his 2011 KTM 250 xcw and he said it was just so much easier to ride power wise.  That motor is stock except for a different power valve spring, I'm assuming stiffer. 

So I'm trying to get his Beta to that point that it's easy to ride.  He loves the handling and suspension on the Beta better then the KTM and says if feels more nimble but the motor is too snappy, revvy and harder to manage power in the gnarly stuff. 

I've been searching and found this but can't find any info on JD's site about it. 

On 8/14/2017 at 11:12 AM, monstersumo said:

installed the jd jet kit power valve shim, I really like how linear the power delivery is without the second spring

If anyone has any suggestions I'm all ears, I don't want him to want to go back to KTM!  This is my best riding bud, and one of the key riders in our area that everyone respects and looks to.  He has to love his Beta and I've got to make it work for him! 

 

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Two questions, does he have the map switch? And what is he running the power valve at?

 

My 17' 250rr is the first 2 stroke I have owned and naturally I found it snappy when I first got it. Now that I'm use to it I find it very linear and easy to ride motor wise. I did however have to tweak it to get there.

 

I tried every PV setting and settled on 2 in. Half turn in past stock. Crazy how noticeable it is. Just last ride I switched back to the stock 1.5 turns thinking I could handle it now. Right away i noticed the difference and found it much snappier in the tight stuff. Found it a little to barky for me and switched back to 2. Flush was cool too, made it more 300 like to me. However, I noticed it tiring me out quicker on longer rides.

 

So for me, map switch on the cloudy setting with 2 turns in on the PV works great. Also bumped up 2 teeth in the rear to lug 3rd gear more.

 

 

Edited by NW_drZ
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G2 Throttle Tamer might help with the snap at lower RPM.  You might also consider some Xtrainer-ish mods, like smaller pipe, different CDI, or PV spacer on the left-hand side of the engine.  Basically the opposite of what Xtrainer riders looking for more snap are doing.  Just brainstorming...

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Agree with NW drz . just tamed my 300rr down with power valve turned in 2.and half turns. Ran map 1 . and also added recluse. And run 4lbs in rear tire . did this for a technical track last week and loved it. Tubliss in rear.

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By far the best thing to do is rejet with the Suzuki needles. I can run the PV full open (flush) , in hot map, in very rocky single track. Bike has a cut head, 1.1 mm squish, 2O5 PSI, and it's still smooth. I have a G2 as well, that I installed when the bike was a 300. Bike is very easy to ride fast like this, today was a little greasy in the AM from rain earlier in the week, great ride no issues. FWIW, @ 1K' , 60 - 90 deg, this is perfect :

NEDW #3
38p
168M
As 1.5t

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How about just get an Allen wrench and  adjust the power valve first. That's super easy and the simplest thing to do. I guess the map switch too but I figure that's got to be the first thing to check and figure you guys had to have done that first.

Are there differences in 250 re power from the last few years? I have a 15 300 rr and it's the same top end as the 14 300 re . It's super mellow unless I adjust it more aggressively. Even so it's easy to ride.  

I rode a 16 300 and it seemed the same as my bike.except for the oi stuff. . So for 17 is there a difference??

Edited by hawaiidirtrider
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The PV adjuster just preloads the spring.  What this means is it opens later, but at the same rate.  The PV spring rate determines how fast the valve opens once it starts.  Spring physics just like suspension.  What this seems to do in practice is make the bike rev a bit slower when the PV is closed but then hit at a higher RPM when the valve snaps open.  Personally I prefer it to open quick at a slightly lower RPM.  This works very well with the jetting I noted.  Its a super easy 250 to ride, I like it much better than the 300 as it has totally manageable power at all times.  A little more clutch on some technical climbs but its worth it, the bike feels lighter and more agile than it did as a 300, and it vibrates even less.  I like to work the bike rather than the bike work me.  My bike is a '13 300 RR Race with a new 250 kit (top end, PV springs, CDI). 

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15 hours ago, GP said:

By far the best thing to do is rejet with the Suzuki needles. I can run the PV full open (flush) , in hot map, in very rocky single track. Bike has a cut head, 1.1 mm squish, 2O5 PSI, and it's still smooth. I have a G2 as well, that I installed when the bike was a 300. Bike is very easy to ride fast like this, today was a little greasy in the AM from rain earlier in the week, great ride no issues. FWIW, @ 1K' , 60 - 90 deg, this is perfect :

NEDW #3
38p
168M
As 1.5t

Thanks for the replies!  I'm going to get the NEDW needle and set up jetting like you're running.  We're at 1000 - 1500 ft so should work well, but we are getting into colder weather now, I'd say 50 - 70 degrees and eventually colder as we get into October.  The G2 is probably a good option as well.

3 hours ago, GP said:

The PV adjuster just preloads the spring.  What this means is it opens later, but at the same rate.  The PV spring rate determines how fast the valve opens once it starts.  Spring physics just like suspension.  What this seems to do in practice is make the bike rev a bit slower when the PV is closed but then hit at a higher RPM when the valve snaps open.  Personally I prefer it to open quick at a slightly lower RPM.  This works very well with the jetting I noted.  Its a super easy 250 to ride, I like it much better than the 300 as it has totally manageable power at all times.  A little more clutch on some technical climbs but its worth it, the bike feels lighter and more agile than it did as a 300, and it vibrates even less.  I like to work the bike rather than the bike work me.  My bike is a '13 300 RR Race with a new 250 kit (top end, PV springs, CDI). 

He says he's played with different settings on the PV with little effect.  So do they make a stiffer spring?  He asked about that, said his KTM ran the same as the Beta until he put the stiffer PV spring in. 

The perfect example of our terrain is the Tennessee Knockout, it's almost identical, so good smooth power is important.  We just had a big event this weekend and he had to park the Beta because of loose rear wheel bearings so he ran his KTM.  He led groups through all our worst stuff both days and when I asked him Saturday what it was like to ride his KTM again, he said "it was sooo easy compared to the Beta".  I didn't want to hear that, I'm the dealer so I've got to get his bike how he likes.  Lots of people look up to Bill and it's important he loves his Beta!

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57 minutes ago, Danceswithtrees said:

Thanks for the replies!  I'm going to get the NEDW needle and set up jetting like you're running.  We're at 1000 - 1500 ft so should work well, but we are getting into colder weather now, I'd say 50 - 70 degrees and eventually colder as we get into October.  The G2 is probably a good option as well.

He says he's played with different settings on the PV with little effect.  So do they make a stiffer spring?  He asked about that, said his KTM ran the same as the Beta until he put the stiffer PV spring in. 

The perfect example of our terrain is the Tennessee Knockout, it's almost identical, so good smooth power is important.  We just had a big event this weekend and he had to park the Beta because of loose rear wheel bearings so he ran his KTM.  He led groups through all our worst stuff both days and when I asked him Saturday what it was like to ride his KTM again, he said "it was sooo easy compared to the Beta".  I didn't want to hear that, I'm the dealer so I've got to get his bike how he likes.  Lots of people look up to Bill and it's important he loves his Beta!

I don't think they have a spring assortment like the KTM.  I know the springs are different for the 300 but I would think the 300 opens sooner as it revs less overall, meaning the spring would be softer.  Motoxgiant would know for sure.  Also, the KTM springs while similar in design are completely different rates.  Get the NEDW, NEDH, NECW, NECH.  Then you can fine tune with two dias. in 1/2 clip position increments.  I'll move to H dia soon here.  Never met a modern 250/300 that couldn't be tuned great with these needles.   The stock needle family is old school and has been used in older KTMs and GGs for years, rich off idle and then leans out quick, hence more hit.  My terrain is the same, very rocky, technical, with rock faces and slabs, short steep elevation changes, and slick after rain.  Very little smooth easy trail. I see no reason at all why a decent rider won't like this bike setup as noted.  I've had a bunch of older GG250s, also great motors, and this Beta is smoother.  Also just rode a neighbors '14 Husaberg and it feels far less refined in delivery.  If this doesn't work then there is something wrong, maybe PV related.

 

Edit:  Just noticed you said he runs the Gnarly.  has he run the stock pipe?  I run the stocker as most Beta riders I know as it gives the best spectrum of power.  Gnarlys have strong bottom and a big blast in the mid which may be aggravating the situation.

Edited by GP
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I can't speak relative to Beta, but my YZ250 (can't remember which yr, but believe it was 2004) had a gnarly when I bought it - thankfully I wiped it out on a stump and replaced it with a stock pipe. What a difference, much easier to ride and no unwanted surprises. 

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Just want to update this thread with what we've done to my buddies bike.  We sent the head to RB Designs for a cut, installed the jetting that GP suggested, and installed the Slavens KTM power valve stiff spring.  We also had Steve at PlusOnePerformance valve the forks.

Bill took the bike yesterday and drove to Tennessee to ride and race an invite only hard enduro race.  The race is tomorrow and today they went out with a group to ride local trails.  He just texted me and well here's what he said "Scott-the Beta is stunningly perfect! I'd hug you now if you were here...pulls like a 4 stroke.  Forks are like riding on a cloud! Walt rode it and stopped after 60 yards and exclaimed Holy Shit!"  Walt is another riding buddy of ours and is a 6'4" super talented A rider. 

So thanks for all the suggestions, everything came together as one great package and Bill's now in love with his 250 race.

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Just want to update this thread with what we've done to my buddies bike.  We sent the head to RB Designs for a cut, installed the jetting that GP suggested, and installed the Slavens KTM power valve stiff spring.  We also had Steve at PlusOnePerformance valve the forks.
Bill took the bike yesterday and drove to Tennessee to ride and race an invite only hard enduro race.  The race is tomorrow and today they went out with a group to ride local trails.  He just texted me and well here's what he said "Scott-the Beta is stunningly perfect! I'd hug you now if you were here...pulls like a 4 stroke.  Forks are like riding on a cloud! Walt rode it and stopped after 60 yards and exclaimed Holy Shit!"  Walt is another riding buddy of ours and is a 6'4" super talented A rider. 
So thanks for all the suggestions, everything came together as one great package and Bill's now in love with his 250 race.


GP got me dialed with the Suzuki needles, and Steve revalved my forks and shock. I agree with your buddy Bill, my 17’ 250rr is stunningly perfect now :). It makes things SO much easier than any other bike I have had. And it’s by far the most fun bike I have ever ridden.
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A very effective and free mod to negate the off idle yank is to retard the ign timing.  Moving the  magnetic pu 2mm from stock in the same direction as engine rotation will have a clear and noticeable effect.This is a totally safe procedure. Going the other way,advanced, you really need to know what you are doing because if you dont you can turn aluminum into vapour .

Edited by widebear

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