16 posts in this topic

Posted (edited)

Can i run to the same problem !??
I was watching these type of videos about Motocross Blow up and wondering why this happen ? is it related to the maintenance or just can happen by chance !? 

 

 

 

 

 

Edited by aminem

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could be a combination of things but I bet the leading cause is maintenance, or lack of.

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55 minutes ago, 91kdx25088 said:

could be a combination of things but I bet the leading cause is maintenance, or lack of.

do you think the lack of basic maintenance ( oil/filter) cause this or more advance like checking the valve clearance or .. !? because as a beginner i got worried that i may run to the same problems , i usually change oil and filters but nothing inside the engine :/ . 

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5 minutes ago, aminem said:

do you think the lack of basic maintenance ( oil/filter) cause this or more advance like checking the valve clearance or .. !? because as a beginner i got worried that i may run to the same problems , i usually change oil and filters but nothing inside the engine :/ . 

I, an nobody else, can answer that question. even the maintenance thing is speculation. after enough hours your going to have to adjust valve clearances and replace parts.

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1 hour ago, 91kdx25088 said:

I, an nobody else, can answer that question. even the maintenance thing is speculation. after enough hours your going to have to adjust valve clearances and replace parts.

yes i know that i should start and learn to them on weekends :D , 

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Most common reason for a 4 strokes to grenade is low oil and continuing to re-shimming the valves after they begin to move(wear). Once you have shimmed more than a couple thousandths the potential for them to break increases exponentially.

Sent from my XT1650 using ThumperTalk mobile app

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I'd say the ones on the video were from poor maintenance and/or too many hours on the motor. The KTM 2 stroke was the lack of a functioning kill switch and something not right in the throttle/ throttle linkage. Pretty much all catastrophic engine failures boil down to user error of some sort..

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Most common reason for a 4 strokes to grenade is low oil and continuing to re-shimming the valves after they begin to move(wear). Once you have shimmed more than a couple thousandths the potential for them to break increases exponentially.

Sent from my XT1650 using ThumperTalk mobile app



Aha good point , so i will have some sort of problems in case i dont start to learn and do all engimeaintnance .

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I'd say the ones on the video were from poor maintenance and/or too many hours on the motor. The KTM 2 stroke was the lack of a functioning kill switch and something not right in the throttle/ throttle linkage. Pretty much all catastrophic engine failures boil down to user error of some sort..


Yes agree any type of dirtbike need to be maintained correctly. ... what i underestand is that 250 4t need to be checked more regularly than 450s .

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Yes agree any type of dirtbike need to be maintained correctly. ... what i underestand is that 250 4t need to be checked more regularly than 450s .


This being because a 250F is normally ridden harder than a 450. The machine itself is the same, it's the manner in which it is used.

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This being because a 250F is normally ridden harder than a 450. The machine itself is the same, it's the manner in which it is used.

Yep :) . 450 is awesome :D
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Posted (edited)

30 minutes ago, ohiodrz400sm said:

Most common reason for a 4 strokes to grenade is low oil and continuing to re-shimming the valves after they begin to move(wear). Once you have shimmed more than a couple thousandths the potential for them to break increases exponentially.

Sent from my XT1650 using ThumperTalk mobile app
 

Agreed! My crf250r was shimmed to death by previous owner. I got it rode 3 x and almost boom!  I revalved with the best parts (now with proper airbox cleaning and oil changes I should be good forever! 😨)(brought just the head to Honda to save money) and did everything myself (piston, rings etc) it was my 1st time doing it, but thanks to YouTube and Thumper Talk I got it done and saved mucho money. Now that I know how to do it, im going to rebuild the top end on all 4 of my bikes! Good luck and have fun👍

Edited by Trail_Dude
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Agreed! My crf250r was shimmed to death by previous owner. I got it rode 3 x and almost boom!  I revalved with the best parts (now with proper airbox cleaning and oil changes I should be good forever! )(brought just the head to Honda to save money) and did everything myself (piston, rings etc) it was my 1st time doing it, but thanks to YouTube and Thumper Talk I got it done and saved mucho money. Now that I know how to do it, im going to rebuild the top end on all 4 of my bikes! Good luck and have fun

God bless youtube and thumpertalk ... people here are really helpful.
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Hour meter is the best solution then follow a proper matienence schedule after the install.

That KTM one was hard to watch! Pull the plug wire already!!!!!!!!:facepalm:

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13 hours ago, Smoking 2's said:

Hour meter is the best solution then follow a proper matienence schedule after the install.

That KTM one was hard to watch! Pull the plug wire already!!!!!!!!:facepalm:

why KTM is hard to watch !? 

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4 hours ago, aminem said:

why KTM is hard to watch !? 

The guy didn't know what to do and the bike blew itself up, which could have been prevented if he pulled the plug wire.

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