XR600Fan

Member
Apr 9, 2000
13
0
Hi guys, I am looking at buying a '91 kdx250 from the paper. He says he just rebuilt the top end and it runs good. Only asking $900. What is the history on this bike and year. I had a KDX in the pst and liked it except it topped out about 40 mph.(it did go through all 6 gears as fast as you could shift though). Any opinios appreciated. I love my XR but am getting tired of the weight.
 

spanky250

Mod Ban
Dec 10, 2000
1,490
1
I love my KDX 250, but it isn't really much lighter than your XR. It weighs around 250 lbs. without gas. Don't expect the 250 to be like the KDX 200 you had, it is a totally different animal. The engine is basically a 1989 KX 250 engine with milder porting, a heavy flywheel, and a wide ratio tranny. With a little uncorking, it runs great, with excellent low-end grunt (not as much as that XR, though ;) ) and a strong mid, but it needs a decent exhaust system to replace the stock boat anchor and a lot of rejetting to get it to run anywhere near it's potential. I can hang with all but the fastest 250 MX bikes in acceleration. The stock fork springs are way too soft for anyone over about 140 lbs, but the shock spring is fine for me, I weigh 195 lbs. It makes a great offroad bike with a few mods, and mine has been very reliable. You will have to do top-ends much more frequently than on your XR, though. Top speed on mine is about 75.
 

XR600Fan

Member
Apr 9, 2000
13
0
Thanks for the info. I'll mull it over and see what happens. The smell of two strokes does tend to excite me. How is the availabilty of parts and reliability for this year?
 

stu182

~SPONSOR~
Dec 11, 1999
90
0
One of the most reliable bikes built. Parts are a little tough but not impossible. Just depends on what you need plastic is hardest thing to find cheap.
 

flyinfish

Member
Apr 27, 2001
54
0
I have a love hate relationship with my '91 KDX 250. I love it while I'm riding it but when it breaks I wish I had something else. Parts are never readily available...always have to be ordered. Many after-market companies don't make parts for the 250 ie. steel braided brake lines, graphics, seat covers, limited selection on pipes, etc. I'm very impressed with the power and I'm starting to learn to flick it around instead of vice-versa. For that price though it sounds great...that is if everything's in working order. Check and make sure the front brake is palatable to you. Going from Honda to Kawasaki can be disappointing in the brake department. I really do love my green machine though!

Good luck,

T.J.
 

kevinkdx

Member
Mar 25, 2001
481
0
Hey man if you live anywhere near open woods, the kdx 250 is the bike for you! my brother has a 91kdx200 and i smoke him to ust wiht my 1993 kdx 250. we both have around to the same mods.one tip though first thing to do is get rid of the heavy double layer exaust system and restrictive spark aresstor. Get a Pro-circuit pipe and silencer. I did and man i was impressed. i even out climb my dad who has a XR600! now that is power. i would recomend cleaning the powervalves once every 2 or 3 years cuz that can make a big diference. you might need to chnge the # of teeth on sprockets if you want to go faster. i went one tooth smaller in the back for more top end.other than that for $900 and if it runs, your getting a bargin. I payed $2200 in 1999 for mine but i love it!
 

spanky250

Mod Ban
Dec 10, 2000
1,490
1
Originally posted by kevinkdx
i would recomend cleaning the powervalves once every 2 or 3 years cuz that can make a big diference.
You can't be serious. If you let the valve assembly go that long without cleaning, assuming you actualy ride the bike more than once a year, you are lucky you aren't replacing the actuating arm and governor shaft on a regular basis. The steel teeth on the sub-port wings will shear the teeth right off of the actuating rod if you let the valves get dirty enough to start binding. If it starts to bind very bad, the governor shaft can snap, falling into the tranny and taking out the clutch, primary gears, and who knows what else.

Clean the valves at every top-end service. I usually do a top-end on my 250 every 50 hours or so.

As for pipes, I tried the Pro Circuit, as well as the FMF Fatty that I currently run. They are similar in performance, but not identical. The FMF is noticably stronger in the mid, and hits harder than the PC, but the PC has a smoother transition from low-to-mid, and revs a little higher than the FMF. I would say the FMF is more of a low-to-mid pipe, and the PC leans a little more towards being a rev pipe. For the tight woods that I ride in, the increased torque and midrange pull of the FMF is the better setup.
 

Oregon Trail

~SPONSOR~
Aug 2, 1999
263
0
I've got a 91' KDX250 and like it. Yes I've done all the mods; pipe, silencer, suspension, etc and it works for me. I wouldn't recommend it for someone under 150lb, just too bulky. Pretty reliable bike too. Parts wise, engine and suspension parts are easy to get, 89 KX250, hard things are graphics, side panels, shrouds and some misc braces/guards.
 
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