goldman15

Member
Jun 9, 2001
124
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1st and 2nd gear on my 95 kdx 200 does not seem to have any power. When I'am in 3rd on up everything seems ok. I thought the little power in 1st and 2nd was natural for this bike until I talked to a friend last night who also rides a kdx and he said 1st and 2nd gear on this bike should have great torque? Is he correct and if he is, is it likely my valves are stuck open? It looks like from the shop manual if I take off the KIPS resonator cover I can look in to see if the valves are open. Is this a correct assumption? Thanks for the help.
 

David Trustrum

~SPONSOR~
Jan 25, 2001
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By the very nature of gearing there has to be more torque at the rear wheel in lower gear ratios. The power production of the motor at low revs may be where you perceived or real problem is.

There are a zillion threads on this subject but you might as well bite the bullet & strip the top end as you should periodically clean the valves else they will strip if they haven’t already. Search threads to avoid pitfalls like stripping the actuator nut thingy.
 

Canadian Dave

Super Power AssClown
Apr 28, 1999
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There is a misprint in many of the Factory shop manuals that wrongly identifies the KIPS sub-port valves. Its therefor not uncommon to find engines with the sub-port valves reversed. A quick check is to pull the pipe and look up into the exhaust port. The sub-port valves should be completely closed. While you are there you'll also want to have a look at the main (center) valve as well. Over time carbon can cause it to hang up and not fully close. If its heavily carboned its likely long overdue for a cleaning.

If you pull the top end be sure to properly support the main KIPS shaft to prevent it from being damaged and remember the nut on top is reverse thread. If you do a search and can't find more detailed instruction on the topic get back to us here and we'll go over it again. I do have an article to post on this subject I just need to find the time . . . . . :(

If the valves look ok get back to us and we'll get into it in more detail.

David
 

Canadian Dave

Super Power AssClown
Apr 28, 1999
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Have a look at the clutch cover. You'll see the main KIPS shaft running up vertically (almost) from the centrifugal actuator to the cylinder. When you remove the gray plastic cover to expose the shaft you'll see a nut on top that retains a gear to the shaft. Two important things to note here; one the nut uses a reverse thread and two you need to support the shaft when removing and installing the nut. If you look just below the gear you'll see the diameter of the shaft increases to support the gear. Most people will grasp the shaft here, just below the gear.

This is a week point in the system and its not uncommon for people to attempt to remove the nut not knowing its reverse thread or over torque the nut when installing it. Doing so can damage the shaft near the bottom. The shaft can break and the bottom section falls into the clutch area where any number of nasty things can happen :( The shaft will last the life of the motor if its properly supported. Unfortunately the shop manual doesn't mention the need to support the shaft. It does however include a caution warning the nut uses a reverse thread.

I hope that helps.

David
 

1A

Member
Jul 9, 2001
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A quick check to see if the KIPS valve is opening is to remove the cover on the left hand side of the engine exposing the kips gear. It takes a large flat screwdriver to remove this 1" or so cap at the top front of the cylinder. When you rev the motor, you should see movement if the valves are not stuck.

I, too, encountered the misprint in the service manual. The best bet is as described above. When reassembling the values check for proper operation and forget what it says in the book.
 

goldman15

Member
Jun 9, 2001
124
0
Need more KIPS help!

I finally got a chance to take off the pipe and inspect the sub valves. They are definetly closed, however, I do not know if the main slider valve was open or closed. How can I assess the slider valve position? If the sub valves remained closed at high RPMs would I have any top end at all? I asked the initial question about the KIPS because my bike does not seem to rev with any power at all in 1st or 2nd gear. Should I be able to spin the tires and do wheelies in these gears or is it normal for the KDX to not have alot of power in these gears. I'am new to dirt bikes and this is the first bike I have ever ridden so I have nothing to compare it too. What should I do next for the KIPS. Thanks so much for the help.
 

BRush

LIFETIME SPONSOR
Jun 5, 2000
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You definitely should be able to spin the tires and do wheelies :) . Others have covered the KIPS system pretty thoroughly, so I'll mention some other things to check: If you have an aftermarket silencer like an FMF Power Core or Turbine Core, it needs to be repacked periodically, or you will lose low end when the packing has blown out over time. I once messed up when repacking the silencer and left the packing material way too loose. I had to rev it to the moon and drop the clutch just to get it moving. Great top end, zero bottom, so check your silencer. Note: This *does not* apply to the stock silencer.

Clean the air filter. Need I say more?

When it gets to be way overdue for a top end job, these things lose power. A riding buddy on a bone stock '95 200 had this happen. He had several seasons on it (the KDX is a really tough bike) with just the occasional oil change, when gradually he noticed that hills that he used to torque up, he could no longer ride up without taking a really good run at them. A top end job (with new piston & rings) fixed him right up. It just may be time. If it has been a long time since your bike had a top end, things can get pretty gummed up. After two seasons, mine looked like THIS.
 

goldman15

Member
Jun 9, 2001
124
0
Thanks for the reply BRush. I just replaced the top end about 1 month ago. Could my problems be as simple as jetting or transmission oil? Thanks
 

BRush

LIFETIME SPONSOR
Jun 5, 2000
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I don't think you are giving us enough information to allow meaningful help. Check out Eric Gorr's post "Tips on posting tech questions"

Tell us more about your bike:

  • Cylinder: Stock , Bored, Ported?
  • Pipe
  • Silencer
  • Spark plug
  • Airbox: Stock, drilled, or gone?
  • Current Jetting: Main, Pilot, Jet Needle Number & clip position, air screw pos
  • Temp and altitude
  • Final drive gearing (front/rear sprocket size)?
  • Rider weight

When you say "I just replaced the top end about 1 month ago." does that mean you did it yourself, or had a dealer do it for you? What exactly was done? Just rings?, new piston?. Normally, the disassembly, cleaning, and functional checkout of the power valves is part what you do when doing top end maintenance, but your earlier questions cast doubt about whether that was done.
 

goldman15

Member
Jun 9, 2001
124
0
BRush
My bike is completely stock. As far as the top end what I did was put new piston and rings in. I did take the cylinder to the dealer and they said it looked fine. The mechanic turned the valves and said they are a little tight but not bad. He said if I did not want to take them out to clean just take the cover off the main slider and spray with contact clearner. I didn't do this because there was very little carbon build up. I did talk to someone today who said that my problem could be clutch related since the engine still revs and has solid response in low gears but delivers little power. Does this sound like a possibility to you? Once again when I viewed the sub exhast valves thru the cylinder they are closed no question about it and I do have normal top end.
Any further help is much appreciated. Thanks
 

David Trustrum

~SPONSOR~
Jan 25, 2001
1,396
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Clutch?
Well yeah that could be it but I would have thought you would notice it in higher gears. Simple test, moderately high gear, good traction, preferably up an even slope. Bang the throttle on & if the revs rise quickly without the corresponding traction then the clutch is slipping. If so time to throw in an extra steel plate or a whole new pack of plates.

Note the KDX basket with no plates in it bottoms out before the plates wear to their minimum thickness so an extra steel may cure this if it is the problem.
 

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
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I did talk to someone today who said that my problem could be clutch related since the engine still revs and has solid response in low gears but delivers little power

Well now...that's a bit of new info that's kinda important.

Certainly there's a relationship, which is to say an absolute feel to, the linkage 'twixt engine speed, acceleration and bike movement. If the clutch slips THAT bad (1st and 2nd gear on my 95 kdx 200 does not seem to have any power) it would be fairly obvious.

Certainly do check your clutch. Besides just twisting it (Simple test, moderately high gear, good traction, preferably up an even slope) as David indicates, try fanning your clutch to make sure it hooks up properly when you let off the lever. Any slippage 'twixt the crank and the transmission (read 'clutch') will be quite evident.

Oh, re: remove the cover on the left hand side of the engine exposing the kips gear......

This is true for '95 up. I don't KNOW...but seems there is not a corresponding checkpoint in earlier models ??
 

acutemp

LIFETIME SPONSOR
Sep 4, 1999
197
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goldman 15,
The 95 kdx's had weak clutch springs. If they havent been replaced ,this may be your problem. If so you can replace them with late model 97-01 springs. I have a 95 and replaced them with kx clutch springs which work well but are pretty stiff.--Dan
 

Canadian Dave

Super Power AssClown
Apr 28, 1999
1,202
0
The 1995 KDX220 had weaker clutch springs than later models. If your bike has much time on it and the clutch hasn't recently been serviced it would certainly be a good starting point.

When/if you rebuild it you'll want to install heavier clutch springs along with new plates.

Other problems could cause a similar lack of power but given your explanation of he problem the clutch is a good place to start. Find yourself a hill and do some testing or pull the clutch cover and measure things up.

David
 
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