It could be a few different things, something bent or broke in the transmission and caused it to lock up or your piston could be seized or it could also be somthing with timing or valve clearances. It's hard to say exaclty what went wrong but don't kick it over anymore. It could cause more damage... Grab your service manual and begin teardown and inspection until you figure out what went wrong.
There's a few different things you can try. If the magnet isn't working try using a coat hanger or a wire with a hook on the end. If you have some long skinny pliers those might work as well. Also sometimes it's helpful to remove the left crankcase cover and try and push the chain up far enough to grab it with something up top. If worse comes to worse you may have to remove the cylinder head to get to it which should just be 4 bolts. If you still can't get it pull the cylinder as well.
@wory8 - I am not aware of any books, but i am sure there are several out there. i started working on bikes when I was 14 as well. I wish they had youtube videos then to help me out. Then again I wish they had the internet when I was 14! keep up the interest and willingness to learn!
Yeah you are definitely going to need to look into it. Make sure you have your service manual and i would check your top end. Make sure your valve clearances are in spec and none of them need replaced. Also i would inspect your piston and cylinder and then make sure the timing is on as well. The cost is going to depend on whats wrong inside so that i'm not sure
you can put a sleeve in your 400ex. The cylinder has to be machined to fit in, and the sleeve has to be bored for the new piston. pretty much you need to have a machine shop do it. That is why we sent ours out to be done.
that is up to you. Why be afraid of it though? If you don't try, you will never learn. Just invest in a good service manual to reduce the chance of mistakes. It will be the best money you ever spent on education.
i guess you won't know until you pull it apart. i strongly suggest buying a manual. Highly worth the investment. They are a tiny price compared to the bike, gear, and everything else that goes into the sport.
The cam chain just goes down and around a sprocket that's on the crankshaft, You've got the camchain guides on each side of it and that's about it. Sometimes they will basically fold on themselves and almost get tangled like that. I would take your left crankcase cover off which might take a little bit to get to because you've got your the 2 different pieces to that left side and get to where you can see what's going on with the camchain.
Which bike is this on? Your swingarm bolt will have a washer and nut on one side so with those removed you should be able to nock the bolt right out. You may have to lift the swingarm up and down to allow the bolt to slide out.
I assume you are talking about wheel bearings??? Are you using grease and new seals? Are you making sure the center spacer is in between the bearings? If not, they will fail in no time.
@thevealchop68 - Good questions. This bike seized (broken case lost all the oil and the piston locked up in the cylinder) so there was obvious damage in the cylinder. sometimes there may be deep scratches. If it looks OK, it is a good ideal to measure the bore to see if it is in spec. Most new cylinders don't have sleeves; rather, a nikasil coating. You can have it recoated or sleeved. you can put the bore back to the stock size, or in this case, a bigger bore for a little more power.
unless I have to, never. I don't have any plans to do it. if you can pull your top end apart, watch out 2-stoke bottom end video. The principle is the same. a service manual will guide you on any differences.
@thevealchop68 - "broken case" = egine case broke on a rock; he lost all his oil. The cases are the crank cases - the lower part of the engine your cylinder bolts to. Cylinders can be damaged in several ways. You usualy know when the performance drops, but sometimes you just need to take it apart after so many hours (refer to owner's manual). thanks,
I'm looking at the OE diagrams and i'm not seeing that they used studs on that motor. It's possible your motor has been modified. You may just have to remove the entire motor before removing the cylinder head.
You shouldn't have to break the chain to get it apart. . . The RFS motor is the only one i know of that requires the cam chain to be broken so i would refer to your service manual for proper dissasembly
Also be careful as you don't want to chip or bend or ruin any of those small teeth on the crankshaft when working with the camchain. (In other words don't pull too hard on the camchain or wedge anything down in there)
No you don't have to bore the cylinder if you're only changing the rings... unless you have a damaged cylinder you will be able to just replace the rings on the piston. Be sure to check your ring end gap before installation though.
Need help: make video for Yamaha TW200 service guide: 1) How to replace base gasket (a lot of us who own '05, '06, '07, and '08 TW200 have problem with gasket leak) 2) How to adjust valves 3) How to bore it up to 225cc or 300cc ... Thx!
the piston is part of the top-end. i would pull it apart and inspect. It shouldn't be too expensive to fix on your own. if you have a two-stroke refer to our two-stroke video.
It sounds to me like something broke or came apart with the shift linkage. I would start at the shifter and work your way back checking for anything wrong. You may have to remove the right side case or even split the motor to get to the transmission. It could be a number of different things but it's hard to say exaclty what it is.
@RockyMountainATVMC funny thing is my rmz 450 is getting its top end done right now it needs new intake and exhaust valves new time chain new timing chain sprockets new compression rings new oil control ring new head gasket new cams (high performance) and machined head
We have a bottom end video that shows how to split cases (you can change shift forks while you are there). The valve video is coming soon (the goal is next week). thanks!
Thanks heaps, you seem to cover every queiry i have with doing these jobs, I am new to 4 strokes and this is all i need to do the job in confidence, Great stuff mate!
Thanks. i won't have time to rebuild your specific machine. Refer to our 2-stroke top end video. The process is all about the same. Refer to a manual as you go.
I seriously doubt that most states have any trained/experienced motorcycle mechanics who could do this sort of work effectively and well. I can't, but then again I don't claim that I can nor am I a mechanic. There are factory-authorized shops that claim to be able to do this sort of work, but through conversations and low-level repairs ... I'd be very reluctant to trust them. I do all routine maintenance to keep my RSTD in good/safe condition ... brakes, all fluids, air and gas filters, plugs, bulbs, etc ... but beyond that my only alternative will be bury it.
im 14 and i love dirtbikes, but my dad want let me ride and im tryin to learn how to work on them, do you have a book or anything i could buy about being a mechinic?, and great video.
Hey there! question from a guy who doesnt know shit, but finds this stuff very interesting: how did you know the cylinder was damaged? what signs does someone look for? ...are there situations when the cylinder cannot be re-sleeved???? and finally? when cylinders get re-sleeved, is it possible that some re-sleeve jobs come back with a cylinder bore that does not match the original factory bore measurement? does the bore always have to match the original factory bore?
I have a 92 Yamaha Warrior, and I wanna know if I should attempt to rebuild it myself or take it to the shop? I have no experience working on motors and stuff.
Thanks for this video and your support of our local Colorado Supermoto club. I appreciate and use your sponsorship race gas gift cards! On removing the cam chain, can I use my trusty drive chain breaker tool to do the job or is there something special about the CAM breaker tool? Thanks again!
+Clayton Jacobs The Race Gas Program is awesome! That's good to hear you're taking advantage of it. The drive chain breaker tool i don't think it comes with the correct size pin to pop a Cam chain pin.
hey, im 15, i have a great book called motorcycle maintenance by mark zimmerman. another book that is great, is any service manual for a bike, i have one about my rm125 and it literally shows you how to do any job on the bike.
2 strokes are fun, but gotta love that low end torque.. I have a 2000 rm 250 (2 stroke). A 2004 kx250f and a 2002 yz250f. and I enjoy them all.... but the suzuki is the fastest by far.. and alot easier to rebuild...
@wory8 If your still looking for good repair books u should look at Four-Stroke Performance Tuning by A. Bell or The High-Performance Two-Stroke Engine by John C.Dixon, these resources helped me on some projects, their pretty simple to understand, im the same age so i cant afford a mechanic either.
i work on motors all the time and never ran into one u had to break the cam chain there isnt anyway u can take the cam out after u loosing the tensioner so u dont have to break it and does that tool work on all cam chains?? or just ktms cause u can just remove a couple of links instead of replacing the whole cam chain in the older junk machines
Why do they make it so difficult to take a4 stroke apart. A 2 stroke top end is a piece of cake. Also why do 4 stroke need rebuild less often as 4 strokes?
I have a 2006 Honda 300 ex, it has a top end noise comin in it, sounds like maybe tapids, or a timing chain tick... any idea on common things to happen to these perticualer engines, and what lvl difficulty project i would be getting into to replace the parts, maybe tapids, cam shaft, timing chain, etc....
hi i have an 01 ktm 520 and my engine has studs instead of bolts and i cant get the head to clear the frame... do i have to compress or remove the intake valves to get it to clear? thanks in advance
@RockyMountainATVMC thanks for reply RE: broken case, not sure what it means. Does it refer to the engine block? the cylinders and case are not one unit? what are the symptoms experienced by a bike to indicate the cylinder is damaged? is it recommended for bikers to get engine inspections? when we say the cylinder is damaged, ,we are referring only to the sleeve, or coating, and NOT the aluminum underneath? when is it time to get a new case/ AKA "block?"
HI, I would like to buy the Motion Pro chain breaker tool that you use to break the timing chain, will this same tool work on my Suzuki DR350? and could I also use this tool on the drive chain? Thanks a lot
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It could be a few different things, something bent or broke in the transmission and caused it to lock up or your piston could be seized or it could also be somthing with timing or valve clearances. It's hard to say exaclty what went wrong but don't kick it over anymore. It could cause more damage... Grab your service manual and begin teardown and inspection until you figure out what went wrong.
There's a few different things you can try. If the magnet isn't working try using a coat hanger or a wire with a hook on the end. If you have some long skinny pliers those might work as well. Also sometimes it's helpful to remove the left crankcase cover and try and push the chain up far enough to grab it with something up top. If worse comes to worse you may have to remove the cylinder head to get to it which should just be 4 bolts. If you still can't get it pull the cylinder as well.
@wory8 - I am not aware of any books, but i am sure there are several out there. i started working on bikes when I was 14 as well. I wish they had youtube videos then to help me out. Then again I wish they had the internet when I was 14! keep up the interest and willingness to learn!
Yeah you are definitely going to need to look into it. Make sure you have your service manual and i would check your top end. Make sure your valve clearances are in spec and none of them need replaced. Also i would inspect your piston and cylinder and then make sure the timing is on as well. The cost is going to depend on whats wrong inside so that i'm not sure
Chain tensioner is easy. Just remove it during disasembly. Retract the auto tenstioner when you put it back on. don't force it on.
crankcase breather tube. It prevents the crankcase from building pressure.
you can put a sleeve in your 400ex. The cylinder has to be machined to fit in, and the sleeve has to be bored for the new piston. pretty much you need to have a machine shop do it. That is why we sent ours out to be done.
These vids are so helpful Thanks RM for a great all around service.
that is up to you. Why be afraid of it though? If you don't try, you will never learn. Just invest in a good service manual to reduce the chance of mistakes. It will be the best money you ever spent on education.
i guess you won't know until you pull it apart. i strongly suggest buying a manual. Highly worth the investment. They are a tiny price compared to the bike, gear, and everything else that goes into the sport.
Thanks for your comments. I am trying to finish up the valve replacement video now. i will move onto the CRF250 rebuild we filmed a coulpe weeks ago.
The cam chain just goes down and around a sprocket that's on the crankshaft, You've got the camchain guides on each side of it and that's about it. Sometimes they will basically fold on themselves and almost get tangled like that. I would take your left crankcase cover off which might take a little bit to get to because you've got your the 2 different pieces to that left side and get to where you can see what's going on with the camchain.
it is the stroke of the piston. do a youtube search. Lots of videos will explain it.
I could be the exhaust you have on it. Alot of aftermarket exhausts do this because they are more open. It could also be lean jetting.
that is a good idea. I will put it on my to-do list! thanks
Which bike is this on? Your swingarm bolt will have a washer and nut on one side so with those removed you should be able to nock the bolt right out. You may have to lift the swingarm up and down to allow the bolt to slide out.
I assume you are talking about wheel bearings??? Are you using grease and new seals? Are you making sure the center spacer is in between the bearings? If not, they will fail in no time.
this is why two strokes rock, takes 30 minutes to rebuild a top end.
Thanks for these 2 video,s spot on useful information. Thumbs up..love the RFS engine
I am sure the capacity is similar. If you can fabricate it to fit, it should be fine.
@deerman1212 - it may not be a must, but probably a good idea.
@thevealchop68 - Good questions. This bike seized (broken case lost all the oil and the piston locked up in the cylinder) so there was obvious damage in the cylinder. sometimes there may be deep scratches. If it looks OK, it is a good ideal to measure the bore to see if it is in spec. Most new cylinders don't have sleeves; rather, a nikasil coating. You can have it recoated or sleeved. you can put the bore back to the stock size, or in this case, a bigger bore for a little more power.
unless I have to, never. I don't have any plans to do it. if you can pull your top end apart, watch out 2-stoke bottom end video. The principle is the same. a service manual will guide you on any differences.
@thevealchop68 - "broken case" = egine case broke on a rock; he lost all his oil. The cases are the crank cases - the lower part of the engine your cylinder bolts to. Cylinders can be damaged in several ways. You usualy know when the performance drops, but sometimes you just need to take it apart after so many hours (refer to owner's manual). thanks,
- I would definetly check your valves. I suggest getting a manual to help you with the proceedure and specs.
@0000000000kc - did you pull the plug to see if you are getting spark. If you aren't, you need to have each electrical item checked out. good luck.
I love you guys
I just happen to have a KTM EXC 450 so these videos are just perfect! =D
I'm looking at the OE diagrams and i'm not seeing that they used studs on that motor. It's possible your motor has been modified. You may just have to remove the entire motor before removing the cylinder head.
@human379 - it sounds like it could be low compression. I would have that checked. Check the valve clearence - they may not be closing all the way.
@thehundredsrocks - normal maintenance. They wear out.
You shouldn't have to break the chain to get it apart. . . The RFS motor is the only one i know of that requires the cam chain to be broken so i would refer to your service manual for proper dissasembly
@DaneBowers01 - What special tool? To loosen the cam chain, just remove the cam chain tensioner.
@cinecicleta - Because you have to replace the master link. Both pins must be removed to remove the whole link.
Also be careful as you don't want to chip or bend or ruin any of those small teeth on the crankshaft when working with the camchain. (In other words don't pull too hard on the camchain or wedge anything down in there)
Oh, the oil injector. I don't know much about bleeding them. I haven't seen one of those is a while.
No you don't have to bore the cylinder if you're only changing the rings... unless you have a damaged cylinder you will be able to just replace the rings on the piston. Be sure to check your ring end gap before installation though.
@DaneBowers01 - on that bike, just remove the cam chain tensioner. The cam will come right out.
@luisbalderrama - not really, but the cam and crank need to be in sync.
@bencasey217 - The Tusk Chain riveting tool is $49.99. The link is $5.46. Note that this is only necesary on some KTM's.
it looks sooooo comlex and hard, i can just imagine how hard it would be to remember stuff
Need help: make video for Yamaha TW200 service guide: 1) How to replace base gasket (a lot of us who own '05, '06, '07, and '08 TW200 have problem with gasket leak) 2) How to adjust valves 3) How to bore it up to 225cc or 300cc ... Thx!
the piston is part of the top-end. i would pull it apart and inspect. It shouldn't be too expensive to fix on your own. if you have a two-stroke refer to our two-stroke video.
It sounds to me like something broke or came apart with the shift linkage. I would start at the shifter and work your way back checking for anything wrong. You may have to remove the right side case or even split the motor to get to the transmission. It could be a number of different things but it's hard to say exaclty what it is.
Really in deth and some really good tips, thanks.
@yamaha250Frider62 - i could certainly be both. Check the valves first.
@bozillakilla - No you don't. Most bikes you don't. This RFS KTM motor is the only dirt bike one I know of.
@rama6maiden - Really? That is insane! unless the nikosil coating is damaged, a light hone will make the cylinder good as new.
@human379 - you need a service manual. I don't have the specs for your bike.
Yeah, the dog sneaks into our shots every once in a while:)
@batman16242 - The RFS motor requires the removal of the link. Most 4-strokes don't.
@RockyMountainATVMC funny thing is my rmz 450 is getting its top end done right now
it needs new intake and exhaust valves new time chain new timing chain sprockets new compression rings new oil control ring new head gasket new cams (high performance) and machined head
Great video, very helpful.
thanks for the help i got it out!!
We have a bottom end video that shows how to split cases (you can change shift forks while you are there). The valve video is coming soon (the goal is next week). thanks!
Thanks heaps,
you seem to cover every queiry i have with doing these jobs, I am new to 4 strokes and this is all i need to do the job in confidence,
Great stuff mate!
you have to install a new master link regardless.
@171apples171 - the stator cover broke and the oil dumped out - the rings seized!
@bencasey217 - kind of a critical part that is made to be peened once. KTM sells the part. We actually stock it.
@Murdaland22 - This is one of the more difficult ones. They aren't all this difficult.
KTM have greatly improved their engines since this one.
A fine enough engine. The year 08-09 was pretty bad compared to it
Sorry Scott, I'm not sure which comment or part of the video you are referring to?
@RockyMountainATVMC
alrigth thanx for the help dude!!!
awesome, yet to much complicated 4 me ;] thanks for input
Thanks. i won't have time to rebuild your specific machine. Refer to our 2-stroke top end video. The process is all about the same. Refer to a manual as you go.
I seriously doubt that most states have any trained/experienced motorcycle mechanics who could do this sort of work effectively and well. I can't, but then again I don't claim that I can nor am I a mechanic. There are factory-authorized shops that claim to be able to do this sort of work, but through conversations and low-level repairs ... I'd be very reluctant to trust them. I do all routine maintenance to keep my RSTD in good/safe condition ... brakes, all fluids, air and gas filters, plugs, bulbs, etc ... but beyond that my only alternative will be bury it.
Its not like this is that hard or complicated.
im 14 and i love dirtbikes, but my dad want let me ride and im tryin to learn how to work on them, do you have a book or anything i could buy about being a mechinic?, and great video.
that machine has a sleeve.
Great video
Hey there! question from a guy who doesnt know shit, but finds this stuff very interesting: how did you know the cylinder was damaged? what signs does someone look for? ...are there situations when the cylinder cannot be re-sleeved???? and finally? when cylinders get re-sleeved, is it possible that some re-sleeve jobs come back with a cylinder bore that does not match the original factory bore measurement? does the bore always have to match the original factory bore?
125 2-stroke? What oil pump?
@yz125rider194 - depends on the bike, how hard it is used, etc. Refer to the manual.
Dream job
what benefits do you get by rebuilding a top end ? is it normal maintenance or an upgrade?
I have a 92 Yamaha Warrior, and I wanna know if I should attempt to rebuild it myself or take it to the shop? I have no experience working on motors and stuff.
do you have to put the cam chain at the exact place from were you took it off first ?
I'm just wondering... How do you buy a master link or could you just take out one pin and put that pin back in?
Shouldn't the motor be at TDC before you break the chain?
Thanks for this video and your support of our local Colorado Supermoto club. I appreciate and use your sponsorship race gas gift cards! On removing the cam chain, can I use my trusty drive chain breaker tool to do the job or is there something special about the CAM breaker tool? Thanks again!
+Clayton Jacobs The Race Gas Program is awesome! That's good to hear you're taking advantage of it. The drive chain breaker tool i don't think it comes with the correct size pin to pop a Cam chain pin.
hey, im 15, i have a great book called motorcycle maintenance by mark zimmerman. another book that is great, is any service manual for a bike, i have one about my rm125 and it literally shows you how to do any job on the bike.
thanks for the help man, i been watchin your videos, i do better with hands on then watching lol
@skatejordan12 - you shouldn't need to.
2 strokes are fun, but gotta love that low end torque.. I have a 2000 rm 250 (2 stroke). A 2004 kx250f and a 2002 yz250f. and I enjoy them all.... but the suzuki is the fastest by far.. and alot easier to rebuild...
@wory8 If your still looking for good repair books u should look at Four-Stroke Performance Tuning by A. Bell or The High-Performance Two-Stroke Engine by John C.Dixon, these resources helped me on some projects, their pretty simple to understand, im the same age so i cant afford a mechanic either.
i work on motors all the time and never ran into one u had to break the cam chain there isnt anyway u can take the cam out after u loosing the tensioner so u dont have to break it and does that tool work on all cam chains?? or just ktms cause u can just remove a couple of links instead of replacing the whole cam chain in the older junk machines
Why do they make it so difficult to take a4 stroke apart. A 2 stroke top end is a piece of cake. Also why do 4 stroke need rebuild less often as 4 strokes?
Also doin this im guessin id have to set my timing over too huh, cause i have no clue how to do that.... have any videos that would show me how?
I have a 2006 Honda 300 ex, it has a top end noise comin in it, sounds like maybe tapids, or a timing chain tick... any idea on common things to happen to these perticualer engines, and what lvl difficulty project i would be getting into to replace the parts, maybe tapids, cam shaft, timing chain, etc....
Hi i am just wondering how do i get the bolt/axle that connects the engine and the swingram out?
I wish I worked somewhere where my dog could hang out too.
hi i have an 01 ktm 520 and my engine has studs instead of bolts and i cant get the head to clear the frame... do i have to compress or remove the intake valves to get it to clear? thanks in advance
Does this also apply to a 2006 rfs? I know some things are different from the 2004.
@RockyMountainATVMC thanks for reply RE: broken case, not sure what it means. Does it refer to the engine block? the cylinders and case are not one unit? what are the symptoms experienced by a bike to indicate the cylinder is damaged? is it recommended for bikers to get engine inspections? when we say the cylinder is damaged, ,we are referring only to the sleeve, or coating, and NOT the aluminum underneath? when is it time to get a new case/ AKA "block?"
HI, I would like to buy the Motion Pro chain breaker tool that you use to break the timing chain, will this same tool work on my Suzuki DR350? and could I also use this tool on the drive chain?
Thanks a lot
hi i have a crf150r, i am having some problems with my hot start lever it's not retrieving back after you pull it, any idea. thanks
in the yamaha yz450f manual they say that the piston and the cylinder is supposed to be changed as a set!!
is that necessery??
very good video!
but i just gotta say, damn 4 pokes are complicated!
It is automatic.
@wory8 if u like workin on bikes try find some dirtbike maGazines they have some Great info
hey, ive got a CRF450 and ive had it for a year, would i have to ajust the timing chain at all with the tensioner? or is it automatic.
Hey would i do it the same way on my ktm525sx 2003