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more grunt for the 250X

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I love my new yz250x but I really wish it had more grunt down low for New England rooty, rocky single tract. I'm coming off a dozen years of the yz250F and I'm not expecting that kind of grunt, but I wish more of the power was lower in the rpm range. I've tried fidgeting with the jets, pj, needle and main...  but doesn't seem to bring a strong pull down low.  It has decent low and great mid, but it really isn't consistent or linear from off-idle through the low and into the mid....  it is soft down low. I like to steer with the power and kick the back out a little to square off turns and such. Instead, it really doesn't break loose until it really breaks loose and then it is past the point of throttle control.

 

As soon as the speed picks up in second gear or third, the power is wonderful and I can see it being a perfect gp bike. Lots of my riding is much slower than that however and I think I'm trying to get the grunt of the KTM--or 250F. I love my LHRB so I don't have the option of fanning the clutch.

 

Is anyone else looking for more low-end and can offer suggestion(s)?  I put on a Gnarly, but it's really no different than the stock. Even 10% better would do the trick.

 

Rekluse, LHRB, Gnarly, pj-45, stock needle, 175 main, elevation 400'IMG_2252.JPG

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I love my new yz250x but I really wish it had more grunt down low for New England rooty, rocky single tract. I'm coming off a dozen years of the yz250F and I'm not expecting that kind of grunt, but I wish more of the power was lower in the rpm range. I've tried fidgeting with the jets, pj, needle and main...  but doesn't seem to bring a strong pull down low.  It has decent low and great mid, but it really isn't consistent or linear from off-idle through the low and into the mid....  it is soft down low. I like to steer with the power and kick the back out a little to square off turns and such. Instead, it really doesn't break loose until it really breaks loose and then it is past the point of throttle control.

 

As soon as the speed picks up in second gear or third, the power is wonderful and I can see it being a perfect gp bike. Lots of my riding is much slower than that however and I think I'm trying to get the grunt of the KTM--or 250F. I love my LHRB so I don't have the option of fanning the clutch.

 

Is anyone else looking for more low-end and can offer suggestion(s)?  I put on a Gnarly, but it's really no different than the stock. Even 10% better would do the trick.

 

Rekluse, LHRB, Gnarly, pj-45, stock needle, 175 main, elevation 400'📎IMG_2252.JPG

Have you tried the timing  ? Its free . It really help my YZ , havent felt the need to try it on the X yet .

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I love my new yz250x but I really wish it had more grunt down low for New England rooty, rocky single tract. I'm coming off a dozen years of the yz250F and I'm not expecting that kind of grunt, but I wish more of the power was lower in the rpm range. I've tried fidgeting with the jets, pj, needle and main...  but doesn't seem to bring a strong pull down low.  It has decent low and great mid, but it really isn't consistent or linear from off-idle through the low and into the mid....  it is soft down low. I like to steer with the power and kick the back out a little to square off turns and such. Instead, it really doesn't break loose until it really breaks loose and then it is past the point of throttle control.

 

As soon as the speed picks up in second gear or third, the power is wonderful and I can see it being a perfect gp bike. Lots of my riding is much slower than that however and I think I'm trying to get the grunt of the KTM--or 250F. I love my LHRB so I don't have the option of fanning the clutch.

 

Is anyone else looking for more low-end and can offer suggestion(s)?  I put on a Gnarly, but it's really no different than the stock. Even 10% better would do the trick.

 

Rekluse, LHRB, Gnarly, pj-45, stock needle, 175 main, elevation 400'📎IMG_2252.JPG

 

 

 I also added a tooth to the rear Sprocket , and  that helped more than I ever thought it would .

Edited by Rosehill Ryder
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 I also added a tooth to the rear Sprocket , and  that helped more than I ever thought it would .

That's the first thing I would do. You seem to be willing to trade some top speed for more low-end pull. Gearing is cheap and effective.

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I almost ordered a 51t sprocket last week and that may eventually be the thing to do. And/or maybe mess with the timing. So it seems like I'm probably not going to cure it with the carb...??    I'm wondering if the Suzuki needle would help the X.

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Something must be wrong if it doesn't already have more low-end power than a 250f.

I agree, my yz has quite a bit more off the bottom than a 250f.

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Something must be wrong if it doesn't already have more low-end power than a 250f.

immediately off idle a 250f wins.

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that was never my experience but especially not with the EFI 250fs

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I beg to differ...I find a 250f to stall immediately off idle. :excuseme:

that was never my experience but especially not with the EFI 250fs

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that was never my experience but especially not with the EFI 250fs

I had a carbed crf250r. With the pump shot cranked up it would jump off idle. After that initial hit my cr and yz kills it though.

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I would like a lhrb but I'm not sure I could ride my YZ without keeping fingers on the clutch. Lol. Though I still don't find a lack of low end if I keep the pilot and air screw appropriate for the conditions. Man I thought the X would be better down low than a modded YZ.

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I almost ordered a 51t sprocket last week and that may eventually be the thing to do. And/or maybe mess with the timing. So it seems like I'm probably not going to cure it with the carb...??    I'm wondering if the Suzuki needle would help the X.

The Suzuki needle gets rid of the stumble between 1/8 - 1/4 throttle.

NECJ  (p/n 13383-37FE0) $11.54

 

Good Luck!

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A reed spacer helped my 2000.

I don't know if the x already has one. The x is set up as a higher revving lower compression engine.

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52 tooth

head work to clean up lowend snap (rbdesigns, pump or race, both are a huge step up over the stock head)

flywheel weight

rb carb mod (again cleans up bottom end alot)

set timing to stock

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