This video was uploaded just on time! This week im getting my first dirtbike, a ktm 200 exc 2007 with 300 hours on it. I’ll change the piston but i wanted to check the bottom end as well, I’m hoping it’s in good shape so I can start riding earlier. The video was very helpful!
First time doing top end myself. Started this week and your video could not have dorp at a better time, was wondering about my side to side play on the rod and now i know what to look for . Super helpful! Thanks for the video, it is very educational and helps a lot. Keep up the good work.
The lateral play (side to side) is specified in the owners manual and can fairly easy be measured with feeler gauges. Wouldn't it be good to have a spec on the axial play ("top-down") too? I think it can be measured with a dial gauge (like the one you're using). Question is what is allowed...
Ah, sounds like one of the crank seals failed. That's too bad. Certainly if I rebuild my bottom end I'll make a video, but that hopefully won't be for a while on one of my bikes ;-)
@@braenzlig426 I'm using a a Keihin PWK 38mm Air Striker Short with a STIC metering block. Jets are 50 pilot, 182 main, N3EJ needle 3rd clip and air screw 2 turns out.
The only thing you need to check is the axial play. No need for a dial gauge or any of the other stuff. Check up and down and check axial play and done.
I'm confused by your comment. You state that you only check axial play, but but don't use anything to measure it. You don't use a thickness gauge set? But then you also say you also check up/down play. The only additional measurement I showed in the video was lateral play, which is a common check to perform and does require a dial indicator as the movement should be relatively small. To do all of the checks only takes a couple of minutes so I don't see a reason not to do them every piston change.
No measurements for up and down play, if there is movement even slightly - it’s bad. Use a feeler gauge to check axial play is within spec and done. Checking rod play at bottom stroke works but just look to see if it’s bent. Checking lateral play with a dial gauge is not necessary. There is a reason the manual only gives axial play tolerance.
@@duncandiving9748 - Yes, agree with you about up/down play, if you can feel any play the crankshaft needs rebuilding and I did state that in the video. I didn't use anything other than my hand to check up/down play.
@@TokyoOffroadyes but I’m saying you checking “rod play” and using a dial gauge is pointless. Simply checking axial play with a feeler gauge is plenty when checking side to side play.
Not sure why you're so against measuring lateral play. It's a good way of monitoring big end bearing wear and easily and quick to preform as shown in the video. It's a commonly used method.
No, I asked about the side rock, but the dealer didn’t have a spec and it’s not a measurement they do. There is no spec for it in the service manual. I couldn’t find any specs online either. It’s still a useful measurement to monitor over time and is easy to do.
sorry Tokyo ... your crank is NOT in such an O.k. condition ! you didn't put the 0.75mm gauge in for the low end side clearance !!! i saw how the 0.7 went in, but 0.7 IS the limit ! i'm sure the 0.75 could also be put in,with minimal friction felt, even if the 0.8 didn't go in - hence : YOUR CRANK AIN'T SO GOOD ANYMORE ! and if you'll give it a new piston/rings set, you'll have a low end rebuild sooner than you think :-( truth is always bad,but it's better than denial ! i mean, it's not gonna happen in few hours, but my bet is no more than another 50 hours. especially if the bike "works hard" most of the time. please correct me if i'm wrong , i wish i am !
The gap between the conrod and webs is required to allow oil (premix) to lubricate the conrod big end bearing. It will not change during the lifetime of the crank, unless the crank webs move on the rod pin. If the crank webs move on the rod they would typically rotate on the pin, not move in/out laterally and you’ll notice a lot of vibration as the crank will become unbalanced. While measuring the gap is a good check to make, the accuracy is not critical as it is not a wear monitoring measurement. The other checks shown in the video (feeling for play and lateral wobble are far more important and provide a good indication of whether a rebuild is required, or not.
@@TokyoOffroad that's true. i'm glad to be wrong ! and if i may add, what i do is checking the radial play of the lower end while the gauge leaf is in that gap (not stuck! ) ,thus getting an easier more accurate feel of the conrod up/down play ... recently i checked the play in my CR500R, and i was surprised to see the crank is o.k. - after 220 hours !!!! is that a lot, or is it normal for CR500s ? any experience?
Top notch video.. You explain things very well.. Thanks for sharing your knowledge.
This video was uploaded just on time! This week im getting my first dirtbike, a ktm 200 exc 2007 with 300 hours on it. I’ll change the piston but i wanted to check the bottom end as well, I’m hoping it’s in good shape so I can start riding earlier. The video was very helpful!
This was absolutely what I was hoping to see covered. Thank you
First time doing top end myself. Started this week and your video could not have dorp at a better time, was wondering about my side to side play on the rod and now i know what to look for . Super helpful! Thanks for the video, it is very educational and helps a lot. Keep up the good work.
Thanks. Pleased that you found the video useful...
Amazing - exactly what I needed - thanks for this content - invaluable!
Excellent as always
good info very well explained
Very helpfull! Thanks 👍
Very informative thanks 🙏
Great videos 👍🏽
Pleased to hear that you like the videos
Cool, thanks!
The lateral play (side to side) is specified in the owners manual and can fairly easy be measured with feeler gauges. Wouldn't it be good to have a spec on the axial play ("top-down") too? I think it can be measured with a dial gauge (like the one you're using). Question is what is allowed...
After 220 hrs my 17 KTM 300 needs a bottom end (gear oil in the exhaust). Was hopeful you would do that job so I have something to go off of!
Ah, sounds like one of the crank seals failed. That's too bad. Certainly if I rebuild my bottom end I'll make a video, but that hopefully won't be for a while on one of my bikes ;-)
Great vid, do you think KTM 4-stroke bottom end would last the same as a two-stroke bottom end,
KRP - Yes, KTM 4-stroke bottom ends also are renowned for robustness and should be similar.
nice vid ! can you tell me you setup for the carb ? that would be really nice
What bike do you have?
@@TokyoOffroad im riding a gasgas ec 300 which has also keihin 38. just interested if there are big differences in the jetting...
@@braenzlig426 I'm using a a Keihin PWK 38mm Air Striker Short with a STIC metering block. Jets are 50 pilot, 182 main, N3EJ needle 3rd clip and air screw 2 turns out.
Have you the link for KTM service manual?
Tommaso Frigo - I purchased the DVD version of the service manual from my KTM dealer
The only thing you need to check is the axial play. No need for a dial gauge or any of the other stuff. Check up and down and check axial play and done.
I'm confused by your comment. You state that you only check axial play, but but don't use anything to measure it. You don't use a thickness gauge set? But then you also say you also check up/down play. The only additional measurement I showed in the video was lateral play, which is a common check to perform and does require a dial indicator as the movement should be relatively small. To do all of the checks only takes a couple of minutes so I don't see a reason not to do them every piston change.
No measurements for up and down play, if there is movement even slightly - it’s bad. Use a feeler gauge to check axial play is within spec and done. Checking rod play at bottom stroke works but just look to see if it’s bent. Checking lateral play with a dial gauge is not necessary. There is a reason the manual only gives axial play tolerance.
@@duncandiving9748 - Yes, agree with you about up/down play, if you can feel any play the crankshaft needs rebuilding and I did state that in the video. I didn't use anything other than my hand to check up/down play.
@@TokyoOffroadyes but I’m saying you checking “rod play” and using a dial gauge is pointless. Simply checking axial play with a feeler gauge is plenty when checking side to side play.
Not sure why you're so against measuring lateral play. It's a good way of monitoring big end bearing wear and easily and quick to preform as shown in the video. It's a commonly used method.
Can you provide a link to the service manual ?
I purchase my service manuals (DVD versions) from my local KTM dealer. Some of my friends have purchased from kristofsx.com
Would you say this applies to their 4 strokes as well?
shift_love - Yes, the same checks and measurements apply to 4-strokes too.
3:05 is that a crack up the top left?
Its a casting mark.
As Sidecarbod commented, it looks like a casting mark
Did you end up getting a side deflection spec from the KTM dealer ?
No, I asked about the side rock, but the dealer didn’t have a spec and it’s not a measurement they do. There is no spec for it in the service manual. I couldn’t find any specs online either. It’s still a useful measurement to monitor over time and is easy to do.
sorry Tokyo ... your crank is NOT in such an O.k. condition ! you didn't put the 0.75mm gauge in for the low end side clearance !!! i saw how the 0.7 went in, but 0.7 IS the limit ! i'm sure the 0.75 could also be put in,with minimal friction felt, even if the 0.8 didn't go in - hence : YOUR CRANK AIN'T SO GOOD ANYMORE ! and if you'll give it a new piston/rings set, you'll have a low end rebuild sooner than you think :-( truth is always bad,but it's better than denial ! i mean, it's not gonna happen in few hours, but my bet is no more than another 50 hours. especially if the bike "works hard" most of the time. please correct me if i'm wrong , i wish i am !
The gap between the conrod and webs is required to allow oil (premix) to lubricate the conrod big end bearing. It will not change during the lifetime of the crank, unless the crank webs move on the rod pin. If the crank webs move on the rod they would typically rotate on the pin, not move in/out laterally and you’ll notice a lot of vibration as the crank will become unbalanced. While measuring the gap is a good check to make, the accuracy is not critical as it is not a wear monitoring measurement. The other checks shown in the video (feeling for play and lateral wobble are far more important and provide a good indication of whether a rebuild is required, or not.
@@TokyoOffroad that's true. i'm glad to be wrong ! and if i may add, what i do is checking the radial play of the lower end while the gauge leaf is in that gap (not stuck! ) ,thus getting an easier more accurate feel of the conrod up/down play ... recently i checked the play in my CR500R, and i was surprised to see the crank is o.k. - after 220 hours !!!! is that a lot, or is it normal for CR500s ? any experience?