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Reed block Spacer on a 98 KX 250

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I'd like to improve my low end snort and throttle response in all gears and was thinking about installing a reed block spacer, has anyone installed one on their bikes? have you noticed any real difference??

My gearing is 13/49, the carb is jetted perfectly and I have the V-Force 3 reed block installed with a Gnarly pipe and Power Core 2 S/A. Bike runs great but I just want more low end and a snappy throttle response like my 2000 KX 250.

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That bike has gobs of torque, more than the 2000 for sure. If your top end is good, I'd check your reeds or ignition timing. That 98 in stock form will do anything you want it to. Maybe try the stock reeds and cage.

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That bike has gobs of torque, more than the 2000 for sure. If your top end is good, I'd check your reeds or ignition timing. That 98 in stock form will do anything you want it to. Maybe try the stock reeds and cage.
I agree. The '98 was the king of brutal hard-hitting low-to-mid power. If you think your 2000 had better low-end, something is wrong with your '98.

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Generally speaking a reed block spacer would smooth a little snap out of the low end, not give it more low end, but possibly making it easier to ride. Downside is they push the carb back and can make fitment to the airbox a PIA.

The only time I like using them is when the reed tips or stoppers extend in far enough to partial block flow up into the bust or boost port. Then you can use one to pull them out a bit. has nothing to do with tuning for lower though.

For power and snap you want the carb needle and nozzle as CLOSE to the vacuum signal as possible, not pulled back. Gains found with spacers, if any, are usually from the weakened vacuum signal which slightly leans the mix, you can do the same thing by just leaning the jetting,

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on my 125, according to my friend that i got it from it will give me more bottom (hi is a 134 so he doesn't need it)

airbox is easy the clamp on the boot is a pain....

garage.php?do=viewattachment&attachmentid=80317

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I agree. The '98 was the king of brutal hard-hitting low-to-mid power. If you think your 2000 had better low-end, something is wrong with your '98.

Everything I have read about the 98 says it was king of the low end hit, but my 2000 hits like a mule kick and out pulls the 98 thru every gear and the throttle response of the 2000 beats the 98 hands down.

Originally posted by jeekinz:

That bike has gobs of torque, more than the 2000 for sure. If your top end is good, I'd check your reeds or ignition timing. That 98 in stock form will do anything you want it to. Maybe try the stock reeds and cage.

Top end was done last January, around 20-30 hours on it now, compression check indicates 195 PSI, ignition timing is set at factory, no sign of failure on the reeds. I'd put the stock reed and cage in if I had them, bike came with the V-Force. I'm not to impresed with the V-Force at this point.:cheers:

Bike runs good, throttle chop indicates a mocha-brown color on the plug, minimal smoking and splooge out the exhaust so jetting indicates good. The bike just feels sluggish to me on the low to mid range compared to the 2000. The 2000 will lift the front wheel off the ground in 1st-5th gear with out even trying, yet the 98 has trouble getting off the ground in 2nd.

Other then being sluggish I love the bike.:banghead::smirk:

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Something is definitely wrong with your '98 by the way you describe it. It should wheelie with ease in every gear. And the 2000 had much less low-end than the '98. My '02 has better low-end than an '00, and it's still less than a '98. Are you sure the power valve is functioning correctly? Your description sounds to me like damaged drum valves that aren't closing off the sub-ports.

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Something is definitely wrong with your '98 by the way you describe it. It should wheelie with ease in every gear. And the 2000 had much less low-end than the '98. My '02 has better low-end than an '00, and it's still less than a '98. Are you sure the power valve is functioning correctly? Your description sounds to me like damaged drum valves that aren't closing off the sub-ports.

I have owned the bike for 3 years now, it has always been this way. I re-jetted the carb to reduce splooge and smoke, last rebuild found the exhaust /KIPPS system to be in good shape.

I planned to pull the motor out and tear down / inspect but I blew my back out this last weekend and can't even bend down to tie my shoes:banghead:So will have to wait until I quit walking like a neanderthal to tear it down, in the mean time I'm surfing for information and taking muscle relaxers:smirk::banghead:

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All posts are correct.

The 98 should smoke the 00.

Check your current compression.

If it is good, check you reeds.

Get well.

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Everything I have read about the 98 says it was king of the low end hit, but my 2000 hits like a mule kick and out pulls the 98 thru every gear and the throttle response of the 2000 beats the 98 hands down.

Originally posted by jeekinz:

That bike has gobs of torque, more than the 2000 for sure. If your top end is good, I'd check your reeds or ignition timing. That 98 in stock form will do anything you want it to. Maybe try the stock reeds and cage.

Top end was done last January, around 20-30 hours on it now, compression check indicates 195 PSI, ignition timing is set at factory, no sign of failure on the reeds. I'd put the stock reed and cage in if I had them, bike came with the V-Force. I'm not to impresed with the V-Force at this point.:foul:

Bike runs good, throttle chop indicates a mocha-brown color on the plug, minimal smoking and splooge out the exhaust so jetting indicates good. The bike just feels sluggish to me on the low to mid range compared to the 2000. The 2000 will lift the front wheel off the ground in 1st-5th gear with out even trying, yet the 98 has trouble getting off the ground in 2nd.

Other then being sluggish I love the bike.:banghead::smirk:

I think you have the 98 and 2K confused. :ride:

j/k

There is definately something wrong (broken) with the bike. IDK what altitude you are in, but that bike all stock rips. I would swap out the V3 for a stock unit, put the carb back to stock. A Gnarly pipe should work good but I really like Kawi's stock pipes. I was lucky enough to find a super low hour 97/98 pipe on Ebay a while back. It's one of my most prized items. :cheers: My 2000 has 98 head/cyl, carb, ignition, pipe all stock and it rips.

As a matter of fact, I was neck and neck (won some, lost some) with a worked CRF450 sand dragging.....with a 12 tooth front sprocket. :worthy:

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I think you have the 98 and 2K confused. :ride:

j/k

There is definately something wrong (broken) with the bike. IDK what altitude you are in, but that bike all stock rips. I would swap out the V3 for a stock unit, put the carb back to stock. A Gnarly pipe should work good but I really like Kawi's stock pipes. I was lucky enough to find a super low hour 97/98 pipe on Ebay a while back. It's one of my most prized items. :cheers: My 2000 has 98 head/cyl, carb, ignition, pipe all stock and it rips.

As a matter of fact, I was neck and neck (won some, lost some) with a worked CRF450 sand dragging.....with a 12 tooth front sprocket. :worthy:

I live at sea level and ride up to 4000 feet, altitude doesn't have any effect on how the bike runs, sluggish in the woods, dessert, on the beach, it's just plain sluggish.

I've started a search for stock reed / cage I have several stock pipes in the garage so thats not a problem, will tear the motor down after the back heals.

Thanks everyone for the input:thumbsup::banghead:

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I live at sea level and ride up to 4000 feet, altitude doesn't have any effect on how the bike runs, sluggish in the woods, dessert, on the beach, it's just plain sluggish.

I've started a search for stock reed / cage I have several stock pipes in the garage so thats not a problem, will tear the motor down after the back heals.

Thanks everyone for the input:thumbsup::moon:

Something is definitely wrong with your '98 by the way you describe it. It should wheelie with ease in every gear. And the 2000 had much less low-end than the '98. My '02 has better low-end than an '00, and it's still less than a '98. Are you sure the power valve is functioning correctly? Your description sounds to me like damaged drum valves that aren't closing off the sub-ports.
I think you have the 98 and 2K confused. :smirk:

j/k

There is definately something wrong (broken) with the bike. IDK what altitude you are in, but that bike all stock rips. I would swap out the V3 for a stock unit, put the carb back to stock. A Gnarly pipe should work good but I really like Kawi's stock pipes. I was lucky enough to find a super low hour 97/98 pipe on Ebay a while back. It's one of my most prized items. :cheers: My 2000 has 98 head/cyl, carb, ignition, pipe all stock and it rips.

As a matter of fact, I was neck and neck (won some, lost some) with a worked CRF450 sand dragging.....with a 12 tooth front sprocket. :smirk:

Well, my back has finally healed to a point that I can walk without dragging my knuckles on the ground and things like a sneeze or a cough no longer causes my to pee my pants and fall to the ground:lol: so I decided to pull the motor out of the 98 and have a look at the exhaust system.

Jeekinz, Chokey, you guys were right on with the long distance diagnosis, first thing I found was alot of tar like splooge running out of the expansion chamber when I removed the spark arrester. Once I got the motor to the bench and started to tear it bown I found the actuator for the power valve was moving like it should, but the power valves were stuck in place.

Everything was covered in the thick tar and a lot of it was baked on:banghead: After several hours of cleaning this crud off I could finally get to trying to pull the power valves, once they were out a quick inspection found a couple of teeth missing so they went in the scrap pile and new ones have been ordered.

Everything has been cleaned and inspected, new parts on order, including piston & rings (figured I had it apart, my as well take care of that now) everything should be here on Monday.

I can't wait to put the bike back together to see how much difference this will make in the low end, I'll post back after a test ride.

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Well, my back has finally healed to a point that I can walk without dragging my knuckles on the ground and things like a sneeze or a cough no longer causes my to pee my pants and fall to the ground:lol: so I decided to pull the motor out of the 98 and have a look at the exhaust system.

Jeekinz, Chokey, you guys were right on with the long distance diagnosis, first thing I found was alot of tar like splooge running out of the expansion chamber when I removed the spark arrester. Once I got the motor to the bench and started to tear it bown I found the actuator for the power valve was moving like it should, but the power valves were stuck in place.

Everything was covered in the thick tar and a lot of it was baked on:banghead: After several hours of cleaning this crud off I could finally get to trying to pull the power valves, once they were out a quick inspection found a couple of teeth missing so they went in the scrap pile and new ones have been ordered.

Everything has been cleaned and inspected, new parts on order, including piston & rings (figured I had it apart, my as well take care of that now) everything should be here on Monday.

I can't wait to put the bike back together to see how much difference this will make in the low end, I'll post back after a test ride.

:moon:

You're going to be amazed at the difference.

Glad to hear the back's getting better too. You'll be out enjoying your fully restored low-end before you know it...:cheers:

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Why would a reed spacer work? Isn't it the exact oposite of stuffing a crank case? It basically adds volume to the crank case creating less pressure to force the intake charge into the port/cylinder.

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So I finally got a chance to ride the KX after a new top end and a rebuild of the KIPS system, man what a difference!! Lots of low end torque, BIG improvement on the amount of splooge out the tail pipe and climbing the hilly terrain at the local ORV park was a breeze, used to have to feather the clutch all the time to get up, now I just tractor right along!

Thanks to all for your input.

Here's a little video I shot on the ride

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So I finally got a chance to ride the KX after a new top end and a rebuild of the KIPS system, man what a difference!!

Here's a little video I shot on the ride

ahahahahaq!...glad it's running a lot better for you, watch those trees when riding at slow speeds, regardless of what your science teacher told you, they do move. :moon:

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I just noticed a large part of your front fender on the ground at the end of the vid...and yeah, I watched it again!

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