I've been restoring and rebuilding these bikes for a while. Your analysis is spot on IMO. However, the rattle itself is a fairly benign issue based simply on the fact that these bikes can clock hundreds if not thousands of hours on a single jug (with proper routine maintenance.) Your rattle fix is awesome though. Thank you for sharing!! Your other videos are great also. You're making me a better mechanic!
Absolutely brilliant analsys on the rattle problem… thank you very much for the time you took to film and post this vid, and for sharing your method of fixing this issue with the copper shim.. very inventive! I’m currently working on a 06 KDX200 with the rattle issue at the bike shop I’m working at and the other mechanic there thought the rattle was piston slap, I could hear it was likely the power valve but your video has nailed the issue for me. Once again thanks 😊
First thing I would check is the centre valve that slides is not rubbing on the copper shim. There are so many moving parts on the kips you have to inspect everyone in detail, impossible for me to diagnose with just a sentence
EXCELLENT!! THANK YOU! hone the flashing OFF! that will eliminate a stress point. All HP/race engines have ALL CASTING / FLASH defects REMOVED! Because that will be a weak spot where the block will crack! Standard professional procedure! That's what I'm gonna do! Polish the casting flash OFF! Can only help!
Not a bad idea. I had an issue where one of my holes was stripped and had to tap it and throw in another bolt. Mine were gunked up and power valve was siezed up.
You are spot on. My kdx has the same issues. They shouldn't rattle they don't when they are brand new. The other issue you can have on the main power valve is, when it wears and rattles it then changes the port timing. Great video.
I just took apart a kdx engine thinking that rattle is a piston slap. How sensitive are these engines to cylinder/piston clearance? Mine is over spec but the cylinder is also on it's wear limit. I'm thinking, run it till it won't anymore and do a new piston and full recoat of the cylinder
If the piston is forged you can run it with the rattle but obviously there are risks and limits, cast pistons tend to crack with lots of rattle and clearance, I prefer cast pistons
From America, thanks, mate! That’s great information. The copper strip is brilliant and elegant as a simple and effective remedy! A lot of folks aren’t as open to “home made” remedies because they’re bound by “the official word”. I’ve been figuring out “other than conventional” ways of solving mechanical issues since I first started working on mechanical things 45 years ago. I always appreciate folks who think like me! When the time comes for another top end rebuild, or some other reason I need to remove the KIPS on my 89 KDX, I’ll be using the tips you showed me! Again, bravo! And subscribed! 🤙
@@show-me-the-details the spacer to hold the main powervalve unit can be put on the outside to allow the bolts to secure it therefore redusing the risk of it falling into the jug but i would just run a reamer on the jug to get tention however this was worth learning thanks
@@jameszichelle7734 initially there was issues with the head gasket but even after the head gasket issues persisted there was still chronic over heating caused by many pinholes in the cylinder, think they video might be in my Chanel if not I will try upload it
How is performance effected with that big valve sitting a few thou deeper? What about just cutting a little clearance off the cylinder so the bolt head can tighten down to the valve? No shim required.
Thanks! I just traded my 2006 kx250f for a mountain bike and a 1990 kdx 250 it has the rattle I thought it was piston slap but I geuss not your information is of great help, thanks !!!
I've been restoring and rebuilding these bikes for a while. Your analysis is spot on IMO. However, the rattle itself is a fairly benign issue based simply on the fact that these bikes can clock hundreds if not thousands of hours on a single jug (with proper routine maintenance.) Your rattle fix is awesome though. Thank you for sharing!! Your other videos are great also. You're making me a better mechanic!
Absolutely brilliant analsys on the rattle problem… thank you very much for the time you took to film and post this vid, and for sharing your method of fixing this issue with the copper shim.. very inventive!
I’m currently working on a 06 KDX200 with the rattle issue at the bike shop I’m working at and the other mechanic there thought the rattle was piston slap, I could hear it was likely the power valve but your video has nailed the issue for me.
Once again thanks 😊
I just did the copper shim in my kdx, helped a lot, but now the power valve gets stuck open. Any advice?
First thing I would check is the centre valve that slides is not rubbing on the copper shim.
There are so many moving parts on the kips you have to inspect everyone in detail, impossible for me to diagnose with just a sentence
So the bit of copper and the worn bolt hole was the 2 fixes? Awesome video
EXCELLENT!! THANK YOU! hone the flashing OFF! that will eliminate a stress point. All HP/race engines have ALL CASTING / FLASH defects REMOVED! Because that will be a weak spot where the block will crack! Standard professional procedure! That's what I'm gonna do! Polish the casting flash OFF! Can only help!
Very useful video! thanks for this:)
Not a bad idea. I had an issue where one of my holes was stripped and had to tap it and throw in another bolt. Mine were gunked up and power valve was siezed up.
Thanks for sharing, i Just pulled apart my 2001 kx250 power valves and it's exactly the same issue.
You are spot on. My kdx has the same issues. They shouldn't rattle they don't when they are brand new. The other issue you can have on the main power valve is, when it wears and rattles it then changes the port timing. Great video.
15 views in 35mins mate? I cant get that on my vids in 1 year!
😂😆😅
Can anyone point to a good quality video like this of the correct installation and timing of the kips assembly?
I just took apart a kdx engine thinking that rattle is a piston slap. How sensitive are these engines to cylinder/piston clearance? Mine is over spec but the cylinder is also on it's wear limit. I'm thinking, run it till it won't anymore and do a new piston and full recoat of the cylinder
If the piston is forged you can run it with the rattle but obviously there are risks and limits, cast pistons tend to crack with lots of rattle and clearance, I prefer cast pistons
From America, thanks, mate! That’s great information. The copper strip is brilliant and elegant as a simple and effective remedy!
A lot of folks aren’t as open to “home made” remedies because they’re bound by “the official word”. I’ve been figuring out “other than conventional” ways of solving mechanical issues since I first started working on mechanical things 45 years ago. I always appreciate folks who think like me!
When the time comes for another top end rebuild, or some other reason I need to remove the KIPS on my 89 KDX, I’ll be using the tips you showed me!
Again, bravo!
And subscribed! 🤙
Thankyou, appreciate the feedback, yes people that can think outside the square are a dying breed
Never come across one with the ball aspring on the end of the actuator rod. Mine have had a nut which fastens the gear directly on to the rod.
All H series kdx are this way
After all the alterations, he "stopped rattling"?
Yes
What is the thickness of the copper you used mate?
Its 0.5mm
Thanks for sharing your proprietary info on this!😅
Brilliant
You're wrong
You managed 2 words , care to make a full sentence ?
@@show-me-the-detailshahaha!
That was a great response 😂
Wouldn't two copper washes be a better idea
Not necessarily, depends on how much tension the spring has lost over 20 years
@@show-me-the-details I meant that they won't dislodge over time and fall into the bore or valve .
You taught me something but put that spacer on the outside
What spacer are you talking about?
@@show-me-the-details the spacer to hold the main powervalve unit can be put on the outside to allow the bolts to secure it therefore redusing the risk of it falling into the jug but i would just run a reamer on the jug to get tention however this was worth learning thanks
Very informative. Did you ever figure out the head gasket issue? Thank you
Yes, turned out to be pin holes in the cylinder wall, will get it sleeves next week
@@show-me-the-details oh wow, so it wasn’t even the head gasket
@@jameszichelle7734 initially there was issues with the head gasket but even after the head gasket issues persisted there was still chronic over heating caused by many pinholes in the cylinder, think they video might be in my Chanel if not I will try upload it
How is performance effected with that big valve sitting a few thou deeper? What about just cutting a little clearance off the cylinder so the bolt head can tighten down to the valve? No shim required.
Thanks! I just traded my 2006 kx250f for a mountain bike and a 1990 kdx 250 it has the rattle I thought it was piston slap but I geuss not your information is of great help, thanks !!!