KDX250-D Chamber Comparison

[dingerjunkie]

Hello All. Getting ready to purchase a new pipe for the KDX250 project.

As an update for those who saw my other posts, I was able to source an additional bike (runner) locally, and I'm doing a "best of" between the two. One curious find was a very clean, corrosion-free Answer ISDE silencer from the early 90's, complete with the original manufacturer's stickers in place (obviously never repacked). I'll let you know what I think when I repack it and hear it in use. Pics will be up on that little piece in a few days.

Okay, so since I have the Answer silencer, I'm less "married" to FMF as an expansion chamber...no need to have "cuffs match collar," if you know what I mean. Chaparral shows a Pro-Circuit pipe still available for this model. Pricing for both new is within a few dollars on each brand.

I know that people who have tried one or the other usually like what they purchased. Can anyone here give me an apples-to-apples comparison of power characteristics and ownership experience (finish, fit, corrosion issues, durability, etc...) between FMF and PC as it specifically relates to the D-series KDX250?

[dingerjunkie]

...perhaps a different take will be necessary, since many people likely did not purchase both pipes for this model.

If anyone can give a clear evaluation of how a specific aftermarket pipe for this bike compared to the stock chamber (more info than "it was better"), it would be appreciated.

I/we should be able to get a good picture of what to expect from different aftermarket options based on the common point-of-reference.

[KDXGarage]

Congratulations on getting another KDX250.

Can you post a picture of the Answer ISDE spark arrestor? I don't think I have seen that specific model in KDX250 form.

Sorry to be of no help on the pipe.

If you can find the Dirt Bike magazine with the KDX250 hop-up, they used a Pro Circuit on it.

[Jaguar]

technically speaking the pipe should match the porting which is different on the 250 than the 200. But I put a PC on my 200 and liked it for the extra top end power. I've also heard that they fit better than FMF pipes.

[SS109]

I had the PC on mine. Never had the original pipe so all I can give it how the bike ran. My bike had true stump pulling power down low. The bike could chug through anything. Honestly, comparing against an '12 KTM 300XC with an aftermarket pipe, it had just as much bottom end. Against my GG EC250, the KDX absolutely kills it down low and is a little better in the midrange. Mid range was very strong as well and it pulled hard. Top end wasn't as strong as most 250's but still pulled really well. IMO, it had a perfect all around power spread hence why I love the KDX250 so much.

[dingerjunkie]

Wow...that is a stunning endorsement from SS109. Thanks for that. Given that I'm in Michigan woods/swamps, the early top-end signoff would not be a big deal from my perspective.

[SS109]

BTW, I was running 13/50 gearing if that helps. Also, don't get me wrong, the top end was still really good. I had it up to 84.9mph once (GPS verified). I still had plenty of throttle left and it pulled hard all the way up to that speed.

[dingerjunkie]

Jason...I'm in the process of cleaning up the Answer unit right now. In the mean time, this KX250 unit of the same period is basically the same thing, save for different bolt points to the frame..

http://www.ebay.com/itm/New-Answer-snea ... 0732194320

The rear rivets have been drilled out on mine for rebuilding. Back (short) section has the packing, and it was soaked in black oil/spooge. It ran out the front as well when I tipped the silencer once off the bike.

I've contacted Answer to see if there is any lit on the silencer that they may be able to dig up out of the archives.

[KDXGarage]

NEAT! Thanks for the link to the picture.