That one only shows about 1-1.5 hp gain. Really too bad we didn't have someone with a dyno buddy that could do some quantified dyno-measured stage tuning, there seems to be a lot of seat-of-pants fuzziness with all the mods we're doing. The cam mod is the only one I've seen with measured dyno results, unless I've missed others.

 

Here's a dyno chart from an HMF forum, see post #3:
Kawasaki KLX 250 slip on - HMF Engineering Forums

 

The dyno chart I looked at for the SF, which should be the same as the S model, was only about a half horsepower...wasn't it? DJ's charts are all with a basically stock bike and exhaust unless they indicate otherwise...aren't they? I'd think the half horse increase on the 250SF chart is a bone stock SF with "maybe" the airbox lid off. I notice on the KLX300 it picked up a full two horsepower with the kit, and I would guess with the airbox lid off. Anyone have a different take on the DJ charts?

My take on the DJ kits as applied to a bone stock bike is that they are more effective for driveability improvement than absolute power gains. Pure off road models like the KLX300 probably get a slight power boost since they're not as restricted in bone stock condition and so respond better to the improved fuel/air increase. That two horese increase on the 300 is decently impressive for just a DJ kit and perhaps the airbox lid off.

IDRIDR, on that HMF mod, it didn't look like they drilled the slide, and it looked like a stock needle. I don't know...the stock needle kind of sucks from my perspective. Maybe the comparison with other charts might not be as good a comparison.

 

TNC: Yes, that's my take. HMF shows slide not drilled and stock needle shimmed up. On drilling the slide, my assumption is that the drilling the slide improves throttle response, but does not improve horsepower. Do you agree? And on the needle, I'm assuming that the better DJ needle may help the HP through it's applicable range, but that the DJ's needle's real benefit is in driveability, as you suggest.

What I see from the HMF posted dyno chart is the improvement from a better flowing muffler, opened airbox (snorkel removed) and a larger main jet yielding 2+ ponies. That and a fairly good "how to" on removing the carby. Does the DJ needle improve HP in the mid range?? I think so...probably...but I haven't found the charts that prove it.

 

I see my recent posts digressed from the poll....sorry...happened again .

My poll response is .... "wait and see." I'm not in a rush to do this one.

Do other's experience prove a consistent improvement (I'm not convinced)? Are there any long-term problems? Will the mod improve performance on the 331 or 351 (where I'll be going)? Taking the cautious approach...I don't like to be the guinea pig.

 

Well I'm not good with the search functions but I do remember 1 dyno in particular that was 18hp stock and about 24hp after stage two. Several of us discussed it and and said that was quite a gain for the changes made and Zomby wolf chimed in that some might say impossible but the results were there for all to see. My point being that I'm not sure there is anything at all to be gained from the proposed cam mods as nearly the same results that are posted are nearly identical to the common results from stage two type changes. Or that David R's findings are spot on.

 

linkin, I looked high and low for dyno charts, and the greatest power increase I could find from just the DJ kit was 2 horsepower on the KLX300...and that's from DJ. I would think DJ would do as much as possible to eek out as much possible increase as they could for their product. I think the water gets muddied quite a bit as the mods start entering the picture. One guy's Stage 2 may be different from another guy's Stage 2, because DJ says their stage 2 can be used with one or more of the common mods we're used to, and maybe even more aggressive mods like big bore kits. DJ seems to stick with the base model and show the dyno chart for that model in stock trim...though I tend to think they still pulled the airbox lid off the KLX300.

 

All I've read is a slight gain. Not one mentioned the 5-6 hp promised by the OP. One post said of a decrease in top speed?? Dyno info seems to be optimistic... Anyone get a tremendous seat of the pants improvement? Pull your arms out gain?

 

Patience grasshoppers. Give this topic some time. We'll see how it turns out.
You know, if louder pipes make a bike faster, I don't see why anything else couldn't be possible. Has anyone actually finished the mod PROPERLY yet? Correct jetting and all. Have they tried Premium fuel? I know most engines it really don't make a difference but maybe it does here.
Think about this, folks spend big money on pipes, jets, filters, etc. and they gain maybe 3hp (dyno'd) on the average and then brag that it is so awesome. Why are so many folks being so negative about a FREE "mod" that could potentialy do at least the same for hp gains?

 

According to the DJ information, they compared a totally stock 300 to one with their kit and the airbox lid removed, and at 6000rpm the chart shows a 3hp increase (20%). What they didn't mention is which needle was is the "stock" carb, the Calif. needle or the 49 states needle. Just changing to the 49 states needle, removing the airbox lid and butt plug from the exhaust will give a very noticeable boost in mid and upper range power. The DJ needle gives an additional bump to the mid range according to my seat of the pants dyno.

Ride on
Brewster