I'd like to see a follow up on some repairs like these.. I just found your channel an bro I'm stoked how good it looks when you repair things.. You da man
This is a great video, I was always worried about how much goes on in the top end of a four stroke, and stayed with two strokes, because they are pretty basic when it comes to rebuild time, somehow this video made me a little less worried about it could possibly even give my mate a hand his is due, good job mate 🤙
I though about doing my sons xr80 head this way. The cam has 5mm of slop . The hole will look like a rugby ball. Can't or can't afford to buy new heads anymore for that bike. Should have excellent oiling afterwards though. Wish me luck.
I wonder why the camshafts don't have separate slide bearings, but are directly sliding against the frame of the holder. Would be so much easier to repair in case of failure.
The issue I have with this method is I don’t see how the upper cam bearing stays concentric. The bearing surface on the upper bearing is made elliptical by just removing material from the mating surface of the bearing cap.
He removed only 5 thousandths or .10MM of material from the cap in order to bring it back into spec. I don't think is quite necessary for the journal to be 100% circular as that part of the cap will wear in like that eventually anyhow as it has the most pressure when the lobe opens the valve. I would think this will work for enough time before the head will finally need a complete replacement.
I think that under the thrust of the valve springs the bearing seat had become oblong due to wear of the upper bearing by the much harder camshaft, creating the observed play. So, by flattening the foot of the bearing a bit, it should give a more circular shape to the whole bore... But as said before, this is only valid because the backlash is very small.
Great work. Nicely produced video as well. We would really need a guy like you here in Sweden. Strange to see that much up and down movement on the cams on such a new bike. Did you find out if it were the caps which were torqued down too little at some time, or was it the camshaft bore that was worn down resulting in too much clearance in the journals?
to solve that problem on kxf and klx the cam holders/head getting wider and cams seizing, widen/deepen the oil passage and gallery on the cam holder and head ;) Rmz has the same issue on older models they didnt have enough lubrication for cams. the 250`s suffered from this problem more then the 450s
Great video’s I’m putting in a new OEM piston tomorrow on my Kfx 450r I got all new oil seals for the head I know you can’t lap the titanium valve’s but how do I clean them without taking the coating off I know sea foam will help but if I need a little extra what can I use? I heard only thing is brass brush? Before I do that do you know a better way thanks!!
I want to ask I have kx 250f mine broke so bad then we took it to someone and day sed thay wil fix it but thay welded the head so can it be ok if thay weld it or must l get a new 1
3:37 Oooh... I desperately need that tool. Can you post a link where I can get it please? EDIT: I'm serious. I spent hours on Amazon trying to find one. And spent a few hours trying to make one. fail fail tail. I really need one of those. EDIT #2. Never mind. Amazing how I was able to read your mind over the internet. Moments after posting this it finally dawned on me to search for "pick screwdriver". Thanks for making your mind available for reading. :)
Hello, first of all thank you for such magnificent video! Secondly I would like to know what are the polishing wheels at 6:30, Are they specifically for kx-f 450 and where I could find them?
Great video! But I'm wondering, the clearance is getter smaller! How? The cam-shaft is getting polished (=smaller diameter) and the cam-hole is getting polished (=larger hole-diameter). Still, the end-play is less (0,08 to 0,02)!!?? I'm very courious?
The issue I have with this method is I don’t see how the upper cam bearing stays concentric. The bearing surface on the upper bearing is made elliptical by just removing material from the mating surface of the bearing cap.
I had to do something similar to an over tightened caps. 3d printed a linishing dowel wrapped in 1200 wet n dry . Instead of the dremal polisher . I probably wouldnt have fitted those dirty valves and seats back without a bit of clean up too while it's all apart .
Hello. Is this 0.02 mm slack recommended or is this standard? My CRF250 have the same issue but I don't know right measurement of this camshaft slack size to fix it. Also 0,02 mm?
Well done! Do you do such kind of work for anybody ? I am asking for future ... purposes) I am always wondering, why they don't use bearings on other side. Because it this case it will serve too long ?))
@@PaulXchannel Actually yes, but ... How long case works there? 100 000 + km. But in the bike we have usually not so much. Maybe they should use wider surface ...
Great job , i love the your presecion !! I have noticed that if you check and adjust the valve cleareances on the head dissaembled , it's a litlle bit off the proper numbers when you asseble the head to the cylinder. i guess it's beacuse the whole head bends when it's tighted to the engine.
How does that repair it there is wear on those cams and cleaning them up just makes it worse, flattening the base makes the hole elliptical and still worn,
achtung ich hab die gleiche fühlerlehre da sind zwei gleiche fühler zusammen gewesen (vom stanzen). Das war von außen nicht erkennbar aber ich hab alle nachgemessen da ist es mir aufgefallen.
When torquing cam bolts do you think putting assembly lube on the threads and under the head of bolts necessary to get a true torque or do the factory's compansate for binding
Lol, what? I don't understand how removing material would make the tolerances tighter? If it's wallowed out and you can't replace a bearing, looks like you need a new head. Idk the spec for camshaft axial deflection, but there's no way you decreased the tolarence by sanding (removing material).
The roundness formula that I use is: (4 × Area)/(π × Major axis2). Roundness is preferable to a simple index or ratio of linear dimensions (i.e., minor axis/major axis) because if the object or structure is not perfectly circular or oval it will not adequately capture shape information
I wish you lived in my country too many people here in US like to throw stuff away when it is not needed good job keeping things alive
Thanks you very much.
I can do it ..
From where are you?
how come i havent come across this channel earlier? BRILLIANT!
Thanks for watching
Wow you do some incredible work!!! Really enjoy watching your videos and you are able to save and fix it instead of replacing it. :)
Thanks for watching.
I'd like to see a follow up on some repairs like these.. I just found your channel an bro I'm stoked how good it looks when you repair things..
You da man
This is a great video, I was always worried about how much goes on in the top end of a four stroke, and stayed with two strokes, because they are pretty basic when it comes to rebuild time, somehow this video made me a little less worried about it could possibly even give my mate a hand his is due, good job mate 🤙
Thanks for watching .
Cool Video 👍😁 I am currently rebuilding my CB600F engine and this video has given me some good tipps
I am glad.
Thanks.
Wow very nice work .i enjoy every bit of it and i learn some new thinsg and you are the best i see so far putting those spring retainer back with ease
I though about doing my sons xr80 head this way. The cam has 5mm of slop . The hole will look like a rugby ball. Can't or can't afford to buy new heads anymore for that bike. Should have excellent oiling afterwards though. Wish me luck.
👍
I wonder why the camshafts don't have separate slide bearings, but are directly sliding against the frame of the holder. Would be so much easier to repair in case of failure.
The issue I have with this method is I don’t see how the upper cam bearing stays concentric. The bearing surface on the upper bearing is made elliptical by just removing material from the mating surface of the bearing cap.
Exactly my thoughts.
He removed only 5 thousandths or .10MM of material from the cap in order to bring it back into spec. I don't think is quite necessary for the journal to be 100% circular as that part of the cap will wear in like that eventually anyhow as it has the most pressure when the lobe opens the valve. I would think this will work for enough time before the head will finally need a complete replacement.
I think that under the thrust of the valve springs the bearing seat had become oblong due to wear of the upper bearing by the much harder camshaft, creating the observed play. So, by flattening the foot of the bearing a bit, it should give a more circular shape to the whole bore...
But as said before, this is only valid because the backlash is very small.
🧠👍
Great work. Nicely produced video as well. We would really need a guy like you here in Sweden.
Strange to see that much up and down movement on the cams on such a new bike. Did you find out if it were the caps which were torqued down too little at some time, or was it the camshaft bore that was worn down resulting in too much clearance in the journals?
Thanks for watching.
Probably insufficient lubrication.
Greetings from INDONESIA always success🥰🙏👏👍
Bull's-eye ! A precise and delicate job done, eventually !
What brushes do you use for the cam hole polishing?
to solve that problem on kxf and klx the cam holders/head getting wider and cams seizing, widen/deepen the oil passage and gallery on the cam holder and head ;) Rmz has the same issue on older models they didnt have enough lubrication for cams. the 250`s suffered from this problem more then the 450s
Great video’s I’m putting in a new OEM piston tomorrow on my Kfx 450r I got all new oil seals for the head I know you can’t lap the titanium valve’s but how do I clean them without taking the coating off I know sea foam will help but if I need a little extra what can I use? I heard only thing is brass brush? Before I do that do you know a better way thanks!!
Thanks.
Try out very fine Scotch-Brite.
Is the red scotch brite you use on your cams (in the video) okay? If no, what color do you recommend?
Fantastic job clean and smoothly
I love working on my bikes whatever they need
superb as everytime...... so relaxing to watch
Bravo Paul 👍👍👍🙂🎸
Such a relaxing video !
Well done thanks for sharing your work with us 🤜🤛
Thanks
So instead of replacing head and cams I could repair them like this?
Love your marble plate. I have a small one, just big enough to fit a sheet of wet n dry sand paper on, but yours is huge.
It was designed for grinding the cylinder head.
@@PaulXchannel I'm guessing for a 4 cylinder engine, judging by size?
I only make 1 cylinder.
Can buy them relatively cheap from Tombstone makers.
I want to ask I have kx 250f mine broke so bad then we took it to someone and day sed thay wil fix it but thay welded the head so can it be ok if thay weld it or must l get a new 1
Serviço de alta qualidade assistindo do Brasil
How does the oil reaches the valve stem in engines like this one if the valve cap is so tight?
Well done. What were the symptoms that led to the work being done? Down on power?Thanks
The valve clearance could not be set correctly.
@@PaulXchannel Thanks for letting me know
@@PaulXchannel So before doing maintenance, valve adjusting, it was not noticable?
The valves could not be adjusted
3:37 Oooh... I desperately need that tool. Can you post a link where I can get it please?
EDIT: I'm serious. I spent hours on Amazon trying to find one. And spent a few hours trying to make one. fail fail tail. I really need one of those.
EDIT #2. Never mind. Amazing how I was able to read your mind over the internet. Moments after posting this it finally dawned on me to search for "pick screwdriver". Thanks for making your mind available for reading. :)
It's just a screwdriver - a needle.
what is the outer diameter and length of the valve pear kx450 please answer. From Indonesia
The work was done at the highest level.
Thanks for watching
Good work!! New subscriber here..
Hello, first of all thank you for such magnificent video! Secondly I would like to know what are the polishing wheels at 6:30, Are they specifically for kx-f 450 and where I could find them?
Thanks for watching.
You will find everything you need in this catalog.
www.hoffmann-group.com/GB/en/houk/
@@PaulXchannel Thank you!
Did u sand down the bridges just by feeling or did u take any measurements?
Yes.
The camshafts in order.
The holder worn.
what is the mission of that mechanism which on the left hand side exantric shaft ?
Very good!
Perfect job, master!
Thanks for watching
Great solution
Cheers
Thanks
Nice video!
This is just a temporary fix. Not the recommended fix. The bearing races must be bored out and new bearing liners must have been fixed.
Great video! But I'm wondering, the clearance is getter smaller! How? The cam-shaft is getting polished (=smaller diameter) and the cam-hole is getting polished (=larger hole-diameter). Still, the end-play is less (0,08 to 0,02)!!?? I'm very courious?
Thanks.
Main operation - grinding of the camshaft holder. Time 5:00
The issue I have with this method is I don’t see how the upper cam bearing stays concentric. The bearing surface on the upper bearing is made elliptical by just removing material from the mating surface of the bearing cap.
I had to do something similar to an over tightened caps. 3d printed a linishing dowel wrapped in 1200 wet n dry . Instead of the dremal polisher .
I probably wouldnt have fitted those dirty valves and seats back without a bit of clean up too while it's all apart .
Hello. Is this 0.02 mm slack recommended or is this standard? My CRF250 have the same issue but I don't know right measurement of this camshaft slack size to fix it. Also 0,02 mm?
The recommended minimum clearance is 0.02 mm.
When there is smaller clearance there is no room for oil.
@@PaulXchannel thank you. Can I send my damage parts to you?
Have you ever made valve shims, where I live I can't find shims for my quad, was wondering if it's possible to make them.
Making valve washers is no problem but it's expensive.
@@PaulXchannel thanks, either way would be expensive for me. I'd be paying aprox 100 us for the shipping alone to bring it here.
Well done!
Do you do such kind of work for anybody ? I am asking for future ... purposes)
I am always wondering, why they don't use bearings on other side. Because it this case it will serve too long ?))
It's the same in the car cams run in aluminium case.
@@PaulXchannel Actually yes, but ... How long case works there? 100 000 + km. But in the bike we have usually not so much. Maybe they should use wider surface ...
Weight .
Lift of cams?? Can u tell
Nice job👍👍
Great job , i love the your presecion !!
I have noticed that if you check and adjust the valve cleareances on the head dissaembled , it's a litlle bit off the proper numbers when you asseble the head to the cylinder. i guess it's beacuse the whole head bends when it's tighted to the engine.
Thanks.
Yes the values may vary
Parabéns excelente trabalho sou do Brasil parabéns 👍👍🇧🇷
Vera level boss
Muito bom, very good....
Hey Paul. Were do you come from?
But you just cleaned it?
How does that repair it there is wear on those cams and cleaning them up just makes it worse, flattening the base makes the hole elliptical and still worn,
Do not worry.
It works well.
Just curious, did you lap the valves while you had it apart? Nice video, very relaxing.
Thanks.
Titanium valves must not be lapped.
@@PaulXchannel thanks, I did not know that. Learn something every day.
Titanium valves have a coating.
Beautiful!!!!!!😎👏👏👏👏
Wat is that magnet used in the beginning.?
A classic screwdriver converted in the workshop into a magnetic holder, high-performance magnet - Paul X :)
What is that red liquid you put on cams..?
assembly lube
@@PaulXchannel ok..but what exactly..?
Maxima Assembly Lube Grease
Did u count e measure for the shim?? All 4 is 2.45??
2.45 - 2.5
@@PaulXchannel ahh thx for e reply... :) nice job bro. :)
Thanks for watching.
From your video, i can learn more knowledge by repairing or servicing my ownself :) thx bro
👍
Where are you from paul??
achtung ich hab die gleiche fühlerlehre da sind zwei gleiche fühler zusammen gewesen (vom stanzen). Das war von außen nicht erkennbar aber ich hab alle nachgemessen da ist es mir aufgefallen.
Why you don't fix the valves seats?
The customer did not have such a request.
Mantab 👍👍
When torquing cam bolts do you think putting assembly lube on the threads and under the head of bolts necessary to get a true torque or do the factory's compansate for binding
with lubricant it's better
I whish this guy could rebuild my noisy xt600 engine, then I know it is made perfect and push on the gas trusting it
Hây lắm anh ơi
aku iso nyawang wes seneng..
What causes it to fail like that
Probably a lot of operating moto hours.
What is the tool called used at 1:27?
Magnetic holder with dial indicator
Lol, what? I don't understand how removing material would make the tolerances tighter? If it's wallowed out and you can't replace a bearing, looks like you need a new head. Idk the spec for camshaft axial deflection, but there's no way you decreased the tolarence by sanding (removing material).
see video to the end
everything is there
@@PaulXchannel ahh, I'm guessing the thrust washers were absent on disassembly or were replaced with new ones if everything else is the same.
Up and down 0,02 mm its vertical, how about horizontal?
The roundness formula that I use is: (4 × Area)/(π × Major axis2). Roundness is preferable to a simple index or ratio of linear dimensions (i.e., minor axis/major axis) because if the object or structure is not perfectly circular or oval it will not adequately capture shape information
Do you have a website?
No, it's just a hobby.
@@PaulXchannel are all the parts you work on your own??
Yes
i see that sanded down shim... ive done the same lol
Nice
Um trabalho muito organizado
i can inform you i failed. i tried lower camshaft caps and now camshaft dont move freely. blah.
So if the cam journals aren’t too bad u can get away with sanding
Nice. I got a 2015 kx450f I just installed a new transmission in. Got a video on my channel If you're interested.
Now your really being facetious, using milling machine as valve spring compressor:)
0:33 looks like a smug guy wearing sunglasses lol
Yep. My ex usually said that in my YZF somebody (alien) look on her from inside of the frame)
I see no problem, I would bet you can get plenty of hours with this repair. Nevermind the armchair engineers on here.
It will be very expensive error hahaha
Top de mais
No! You missed both o-rings!
Can I pay you to rebuild my 2016?! lol
❤
Я тоже люблю свой,, mitutoyo,,
Top 🔝
You forgot to put one o-ring
The O-ring is inserted after the engine has been assembled.
When setting the valve you do not need it there.
agujeros ovalados...
Why dont use the same process that ktm 350?
less wear
other type of holder
🔥🔥🔥🔥🔥👍
👍
I would have replaced the valves when the head was open already.
Me too.
But there was no such request from the customer.
My 2009 Kawasaki need a job like that this is my phone number if you have time to work we that
Démonté nettoyé polissage apperage pour au final remonter avec les soupapes dégueulasses.... comment dire 🤮
あり得ない。
酷い作業だ。
🤔🤔🤔
So instead of replacing head and cams I could repair them like this?
Parabéns excelente trabalho sou do Brasil parabéns 🇧🇷👍
Very good!
Thanks
Nice